Merge branch 'master' of bitbucket.org:bluetradesys/spark into ice_exec

Mass cancel messaging nits
2019-04-02 11:22:33 -04:00 · 2019-04-02 11:13:40 -04:00 · 2019-04-02 09:42:20 -05:00 · 2019-04-02 14:11:57 +00:00 · 2019-04-02 09:01:53 -05:00 · 2019-04-01 18:11:48 -04:00
373 changed files with 17075 additions and 3423 deletions
@@ -75,6 +75,7 @@
            "name": "SparkVM Launch",
            "type": "cppdbg",
            "request": "launch",
+            
            "program": "/home/bts/spark/build/ninja_debug/server/sparkd",
            "args": ["run"],
            "stopAtEntry": false,
@@ -96,7 +97,12 @@
                    "description": "Skip STL",
                    "text": "skip -gfi /usr/include/c++/7/bits/*.h",
                    "ignoreFailures": true
-                }
+                },
+                {
+                    "description": "LD LIBRARY",
+                    "text": "set env LD_LIBRARY_PATH=.",
+                    "ignoreFailures": false
+                }                
            ],
            "pipeTransport": {
                "pipeCwd": "${workspaceRoot}",
@@ -208,10 +214,10 @@
            "name": "MD Tests",
            "type": "cppdbg",
            "request": "launch",
-            "program": "/home/bts/spark/build/ninja_debug/src/server/sparkd/sparkd",
+            "program": "/home/bts/spark/build/ninja_debug/server/sparkd",
            "args": ["test", "[md]"],
            "stopAtEntry": false,
-            "cwd": "/home/bts/spark/build/ninja_debug/src/server/sparkd/",
+            "cwd": "/home/bts/spark/build/ninja_debug/server/",
            "environment": [],
            "externalConsole": true,
            "MIMode": "gdb",
@@ -55,6 +55,8 @@ else ()
    COMMAND ln ARGS -sf ${CMAKE_BINARY_DIR}/web ${CMAKE_BINARY_DIR}/server
    COMMAND ln ARGS -sf ${CMAKE_BINARY_DIR}/data_files ${CMAKE_BINARY_DIR}/server
    COMMAND ln ARGS -sf ${CMAKE_BINARY_DIR}/src/lib/libspark.so ${CMAKE_BINARY_DIR}/server
+    COMMAND ln ARGS -sf ${EXTERNALS_ROOT}/lib/Release/libOnixS.IceImpactMulticastPriceFeedHandlerCpp.so.3.13.0.0 ${CMAKE_BINARY_DIR}/server
+    COMMAND ln ARGS -sf ${EXTERNALS_ROOT}/lib/Release/libACE-5.7.5.so ${CMAKE_BINARY_DIR}/server
    COMMAND mkdir ARGS -p ${CMAKE_BINARY_DIR}/server/plugins
    COMMAND ln ARGS -sf ${CMAKE_BINARY_DIR}/sdk/examples/order_plugin_example.so ${CMAKE_BINARY_DIR}/server/plugins/
    COMMENT "Creating server runtime layout"
@@ -5,6 +5,7 @@ sort_by = "weight"
 insert_anchor_links = "right"
 +++

+{{ youtube(id="RZU9Wj0cETo") }}

 <div>
    <iframe width="560" height="315" src="https://www.youtube.com/embed/XEZpuPAgMC0" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
@@ -406,6 +406,8 @@ insert_anchor_links = "right"

 ##  Algo Studio

+{{ youtube(id="DHIa5tnifKc") }}
+
 -  The BTS Algo Studio was built for users to experience algo composability
    never seen before in a professional futures trading system.

@@ -4,6 +4,26 @@ weight = 3
 sort_by = "weight"
 insert_anchor_links = "right"
 +++
+## 1.5.7
+### User Visible Changes
+  - New videos have been added to the manual describing the [Algo Studio](./bts_spark/Trading/index.md#algo-studio) and [Spreader](./bts_spark/Spreader/index.md)
+  - Fixed a bug that occasionally would cause windows to be position outside the visible screen on startup
+  - Fixed a bug in the order book form that would occasionally cause the Recreate Order option to be unavailable
+  - Added a confirmation step to Cancel All, Cancel Buys and Cancel Sells commands
+  - Fixed Aggressor coloring and ladder high/low coloring in the SIM execution gateway
+  - Added initial support for ICE market data
+  - In an effort to streamline the PnL report we've made the following changes:
+    - The PnL report will by default filter for Futures contracts only
+    - If you wish to see Spread contracts again you may change Security Type column filter
+    - The PnL report will now only show rows in which there is a position (net and/or day)
+    - The Exchange, Start PnL, Total Net Pos, and Total Net PnL columns are now hidden by default
+    - These columns can be restored by toggling their visibility within the PnL's Settings form
+    - A new Traded Today column has been added to the PnL
+      - Filtering on this column will allow a user to restrict the report to only show today's position
+### Internal changes 
+  - Improved organization of the shell notification architecture 
+  - Added logging to help troubleshoot shell exit hang
+
 ## 1.5.6
 ### User Visible Changes
  - Fixed a bug that could cause limits to be erroneously enforced 
@@ -54,3 +54,8 @@ img {
  background: #ccc;
  border: 1px solid #aaa;
 }
+
+iframe {
+  width:560px;
+  height:315px;
+}
@@ -1,3 +1,6 @@
+1.5.7
+- Fixed Aggressor coloring and ladder high/low coloring in SIM
+
 1.4.2
 - Be sure the system has a bts user before deployment.  bts is the superuser, he has all permissions and can see all market data 
 - After deployment re-permission all existing users for trading, riskadmin, and/or md admin permissions as appropriate
@@ -66,6 +66,7 @@ namespace mbts.ui.shell

      protected override void OnExit(ExitEventArgs e)
      {
+         Log.Gen.info("Application.OnExit");
         if (_runtime != null) _runtime.Dispose();
         utils.BTSNativeMethods.finit_spark_lib();
         base.OnExit(e);
@@ -22,7 +22,9 @@ namespace mbts.ui {
         AddBoxesGeometryKey = nameof(AddBoxesGeometryKey),
         AddFileGeometryKey = nameof(AddFileGeometryKey),
         AddFileThinGeometryKey = nameof(AddFileThinGeometryKey),
+         AttachAlgosGeometryKey = nameof(AttachAlgosGeometryKey),
         CheckMarkGeometryKey = nameof(CheckMarkGeometryKey),
+         DetachAlgosGeometryKey = nameof(DetachAlgosGeometryKey),
         DiskGeometryKey = nameof(DiskGeometryKey),
         DiskFileGeometryKey = nameof(DiskFileGeometryKey),
         DocumentGeometryKey = nameof(DocumentGeometryKey),
@@ -39,6 +41,7 @@ namespace mbts.ui {
         PaymentGeometryKey = nameof(PaymentGeometryKey),
         PencilGeometryKey = nameof(PencilGeometryKey),
         PlayGeometryKey = nameof(PlayGeometryKey),
+         ProhibitedGeometryKey = nameof(ProhibitedGeometryKey),
         StarGeometryKey = nameof(StarGeometryKey),
         ToolsGeometryKey = nameof(ToolsGeometryKey),
         TrashGeometryKey = nameof(TrashGeometryKey),
@@ -115,6 +118,7 @@ namespace mbts.ui {
      public static ImageSource AddBoxes => create_icon(AddBoxesGeometryKey);
      public static ImageSource AddEncircled { get { return load_resource_and_freeze("AddEncircled"); } }
      public static ImageSource AddFile => create_icon(Smashicons.AddFileGeometryKey);
+      public static ImageSource AttachAlgos => create_icon(AttachAlgosGeometryKey);
      public static ImageSource Beaker { get { return load_resource_and_freeze("Beaker"); } }
      public static ImageSource Book { get { return load_resource_and_freeze("Book"); } }

@@ -139,6 +143,7 @@ namespace mbts.ui {
      public static ImageSource CheckMark => create_icon(CheckMarkGeometryKey);
      public static ImageSource Clock { get { return load_resource_and_freeze("Clock"); } }
      public static ImageSource Defrag { get { return load_resource_and_freeze("Defrag"); } }
+      public static ImageSource DetachAlgos => create_icon(DetachAlgosGeometryKey);
      public static ImageSource Disk => create_icon(DiskGeometryKey);
      public static ImageSource DiskFile => create_icon(DiskFileGeometryKey);
      public static ImageSource Display { get { return load_resource_and_freeze("Display"); } }
@@ -158,6 +163,7 @@ namespace mbts.ui {
      public static ImageSource Knight { get { return load_resource_and_freeze("Knight"); } }
      public static ImageSource Payment => create_icon(PaymentGeometryKey);
      public static ImageSource Pencil => create_icon(PencilGeometryKey);
+      public static ImageSource Prohibited => create_icon(ProhibitedGeometryKey);
      public static ImageSource RedoCircular => create_icon(UndoCircularGeometryKey, Brushes.Black, null, new ScaleTransform(-1, 1));
      public static ImageSource Spawn { get { return load_resource_and_freeze("Spawn"); } }
      public static ImageSource Star => create_icon(StarGeometryKey);
@@ -40,6 +40,69 @@
    </sys:String>
  </x:Array>

+  <!--File (the icon is free to use if we include this information in our credit section)
+    Source: https://www.flaticon.com/authors/freepik
+    Ttile: Unlink free icon
+    Credit: Icon made by Chanut from www.flaticon.com-->
+  <x:Array x:Key="{x:Static mbts:Icons.AttachAlgosGeometryKey}" Type="sys:String">
+    <sys:String>
+      M51.173,3.801c-5.068-5.068-13.315-5.066-18.384,0l-9.192,9.192c-0.781,0.781-0.781,2.047,0,2.828
+      c0.781,0.781,2.047,0.781,2.828,0l9.192-9.192c1.691-1.69,3.951-2.622,6.363-2.622c2.413,0,4.673,0.932,6.364,2.623
+      s2.623,3.951,2.623,6.364c0,2.412-0.932,4.672-2.623,6.363L36.325,31.379c-3.51,3.508-9.219,3.508-12.729,0
+      c-0.781-0.781-2.047-0.781-2.828,0s-0.781,2.048,0,2.828c2.534,2.534,5.863,3.801,9.192,3.801s6.658-1.267,9.192-3.801
+      l12.021-12.021c2.447-2.446,3.795-5.711,3.795-9.192C54.968,9.512,53.62,6.248,51.173,3.801z
+    </sys:String>
+    <sys:String>
+      M27.132,40.57l-7.778,7.778c-1.691,1.691-3.951,2.623-6.364,2.623c-2.412,0-4.673-0.932-6.364-2.623
+      c-3.509-3.509-3.509-9.219,0-12.728L17.94,24.306c1.691-1.69,3.951-2.622,6.364-2.622c2.412,0,4.672,0.932,6.363,2.622
+      c0.781,0.781,2.047,0.781,2.828,0s0.781-2.047,0-2.828c-5.067-5.067-13.314-5.068-18.384,0L3.797,32.793
+      c-2.446,2.446-3.794,5.711-3.794,9.192c0,3.48,1.348,6.745,3.795,9.191c2.446,2.447,5.711,3.795,9.191,3.795
+      c3.481,0,6.746-1.348,9.192-3.795l7.778-7.778c0.781-0.781,0.781-2.047,0-2.828S27.913,39.789,27.132,40.57z
+    </sys:String>
+  </x:Array>
+
+  <!--File (the icon is free to use if we include this information in our credit section)
+    Source: https://www.flaticon.com/authors/freepik
+    Ttile: Disconnected chains free icon
+    Credit: Icon made by Chanut from www.flaticon.com-->
+  <x:Array x:Key="{x:Static mbts:Icons.DetachAlgosGeometryKey}" Type="sys:String">
+    <sys:String>
+      M462.557,77.627c-14.323-25.556-41.488-41.423-70.889-41.423c-13.835,0-27.54,3.585-39.602,10.364
+      l-152.557,85.635l17.55,31.279l152.565-85.635c6.747-3.78,14.371-5.779,22.069-5.779c16.428,0,31.596,8.852,39.594,23.11
+      c5.909,10.535,7.356,22.752,4.072,34.408c-3.268,11.656-10.876,21.346-21.411,27.255l-138.291,77.604
+      c-2.634-16.851-10.494-32.392-22.793-44.699c-21.687-21.663-56.063-29.328-84.935-18.964l-12.485,4.495l12.128,33.734
+      l12.534-4.471c16.127-5.869,35.319-1.496,47.406,10.567c6.974,6.982,11.388,15.826,12.786,25.41
+      c-0.585-0.138-1.171-0.285-1.731-0.447c-11.681-3.284-21.354-10.9-27.271-21.476l-6.519-11.518l-31.303,17.59l6.56,11.518
+      c10.6,18.915,27.93,32.571,48.836,38.44c0.723,0.187,1.455,0.39,2.187,0.561c-1.105,1.398-2.284,2.731-3.536,3.983
+      l-114.32,114.328c-8.551,8.543-19.931,13.241-32.035,13.241c-12.112,0-23.492-4.698-32.027-13.241
+      c-8.535-8.543-13.233-19.907-13.233-32.027c0-12.112,4.698-23.483,13.233-32.018l99.291-99.282l-25.369-25.369l-99.282,99.282
+      C8.446,319.427,0,339.806,0,361.468c0,21.679,8.446,42.049,23.776,57.396c15.339,15.339,35.709,23.768,57.388,23.768
+      s42.049-8.429,57.388-23.768l114.345-114.32c8.372-8.405,14.81-18.566,18.842-29.71c6.625-1.764,12.924-4.3,18.777-7.6
+      l140.99-79.115c18.875-10.608,32.514-27.946,38.375-48.828C475.749,118.4,473.148,96.493,462.557,77.627z
+    </sys:String>
+    <sys:String>
+      M173.171,141.769c4.503-0.821,7.511-5.145,6.69-9.657l-17.103-94.942
+      c-0.821-4.519-5.162-7.527-9.665-6.722c-4.511,0.821-7.527,5.145-6.706,9.673l17.111,94.925
+      C164.311,139.575,168.644,142.574,173.171,141.769z
+    </sys:String>
+    <sys:String>
+      M43.561,191.776l94.934-17.119c4.519-0.821,7.527-5.145,6.706-9.657
+      c-0.821-4.528-5.145-7.543-9.649-6.722L40.61,175.405c-4.503,0.797-7.519,5.145-6.698,9.657
+      C34.717,189.582,39.058,192.589,43.561,191.776z
+    </sys:String>
+  </x:Array>
+
+  <!--File (the icon is free to use if we include this information in our credit section)
+    Source: https://www.flaticon.com/authors/chanut
+    Ttile: Cancel free icon
+    Credit: Icon made by Chanut from www.flaticon.com-->
+  <sys:String x:Key="{x:Static mbts:Icons.ProhibitedGeometryKey}">
+    M32.759,0C14.696,0,0,14.695,0,32.759s14.695,32.759,32.759,32.759s32.759-14.695,32.759-32.759S50.822,0,32.759,0z
+    M6,32.759C6,18.004,18.004,6,32.759,6c6.648,0,12.734,2.443,17.419,6.472L12.472,50.178C8.443,45.493,6,39.407,6,32.759z
+    M32.759,59.518c-5.948,0-11.447-1.953-15.895-5.248l37.405-37.405c3.295,4.448,5.248,9.947,5.248,15.895
+    C59.518,47.514,47.514,59.518,32.759,59.518z
+  </sys:String>
+
  <!--File (the icon is free to use if we include this information in our credit section)
    Source: https://www.flaticon.com/authors/smashicons
    Ttile: File free icon
@@ -137,6 +137,12 @@ namespace mbts.spark {
         public ICommand ask_implied_size_click { get; }
         public ICommand working_asks_click { get; }
         public ICommand default_command { get; }
+         public string market_description {get;}
+         public string cleared_alias { get; }
+         public string product_description { get; }
+         public string hub_alias { get; }
+         public string strip_name{ get; }
+         public string mic_code { get; }

         public ObservableCollection<RowAnimation> row_animations { get; } = new ObservableCollection<RowAnimation>();

@@ -57,6 +57,13 @@ namespace mbts.spark {
         add_col(Columns.SessionLow, "Low", r => r.format_price(r.session_low), nameof(Row.session_low), DefaultColumnWidths.Price, session_low_filter, DataGridFilterKnownTemplates.DoubleMinMax, h_alignment: System.Windows.HorizontalAlignment.Right);
         add_col(Columns.SessionHigh, "High", r => r.format_price(r.session_high), nameof(Row.session_high), DefaultColumnWidths.Price, session_high_filter, DataGridFilterKnownTemplates.DoubleMinMax, h_alignment: System.Windows.HorizontalAlignment.Right);
         add_col(Columns.SecurityKey, "Security Key", r => r.security_key.ToString(), nameof(Row.security_key), DefaultColumnWidths.SecurityKey, security_key_filter, DataGridFilterKnownTemplates.Regex);
+
+         add_col(Columns.MarketDescription, "Market Description", r => r.md.security.HasIce ? r.md.security.Ice.MarketDescription : string.Empty, nameof(Row.market_description), DefaultColumnWidths.SecurityKey, market_description_filter, DataGridFilterKnownTemplates.Regex);
+         add_col(Columns.ClearedAlias, "Cleared Alias", r => r.md.security.HasIce ? r.md.security.Ice.ClearedAlias : string.Empty, nameof(Row.cleared_alias), DefaultColumnWidths.SecurityKey, cleared_alias_filter, DataGridFilterKnownTemplates.Regex);
+         add_col(Columns.ProductDescription, "Product Description", r => r.md.security.HasIce ? r.md.security.Ice.ProductName : string.Empty, nameof(Row.product_description), DefaultColumnWidths.SecurityKey, product_description_filter, DataGridFilterKnownTemplates.Regex);
+         add_col(Columns.HubAlias, "Hub Alias", r => r.md.security.HasIce ? r.md.security.Ice.HubAlias : string.Empty, nameof(Row.hub_alias), DefaultColumnWidths.SecurityKey, hub_alias_filter, DataGridFilterKnownTemplates.Regex);
+         add_col(Columns.StripName, "Strip Name", r => r.md.security.HasIce ? r.md.security.Ice.StripName : string.Empty, nameof(Row.strip_name), DefaultColumnWidths.SecurityKey, strip_name_filter, DataGridFilterKnownTemplates.Regex);
+         add_col(Columns.MicCode, "Mic Code", r => r.md.security.HasIce ? r.md.security.Ice.MicCode : string.Empty, nameof(Row.mic_code), DefaultColumnWidths.SecurityKey, mic_code_filter, DataGridFilterKnownTemplates.Regex);
         //
         void add_col(Columns col_key, string header, Func<Row, string> get_text, string prop, double width, IDataGridColumnFilter filter, string filter_template, bool is_animatable = false, Color? font_color = null, System.Windows.HorizontalAlignment h_alignment = System.Windows.HorizontalAlignment.Left) =>
            columns.Add(new RenderTextColumn<Row, Columns>(col_key, get_text, filter, filter_template) {
@@ -194,6 +201,14 @@ namespace mbts.spark {
      public IDataGridColumnPersistentFilter<Row, IntMinMaxState> working_ask_volume_filter { get; } = new IntMinMax<Row>(r => r.working_ask_volume, nameof(Row.working_ask_volume));
      public IDataGridColumnPersistentFilter<Row, ULongMinMaxState> volume_filter { get; } = new ULongMinMax<Row>(r => r.volume, nameof(Row.volume));
      public IDataGridColumnPersistentFilter<Row, string> security_key_filter { get; } = new RegexFilterVM<Row>(r => r.security_key.ToString(), nameof(Row.security_key));
+      
+      public IDataGridColumnPersistentFilter<Row, string> market_description_filter { get; } = new RegexFilterVM<Row>(r => r.security.HasIce ? r.security.Ice.MarketDescription : "", nameof(Row.market_description));
+      public IDataGridColumnPersistentFilter<Row, string> cleared_alias_filter { get; } = new RegexFilterVM<Row>(r => r.security.HasIce ? r.security.Ice.ClearedAlias : "", nameof(Row.cleared_alias));
+      public IDataGridColumnPersistentFilter<Row, string> product_description_filter { get; } = new RegexFilterVM<Row>(r => r.security.HasIce ? r.security.Ice.ProductName : "", nameof(Row.product_description));
+      public IDataGridColumnPersistentFilter<Row, string> hub_alias_filter { get; } = new RegexFilterVM<Row>(r => r.security.HasIce ? r.security.Ice.HubAlias : "", nameof(Row.hub_alias));
+      public IDataGridColumnPersistentFilter<Row, string> strip_name_filter { get; } = new RegexFilterVM<Row>(r => r.security.HasIce ? r.security.Ice.StripName : "", nameof(Row.strip_name));
+      public IDataGridColumnPersistentFilter<Row, string> mic_code_filter { get; } = new RegexFilterVM<Row>(r => r.security.HasIce ? r.security.Ice.MicCode : "", nameof(Row.mic_code));
+      

      public FilterStates get_filter_states() {
         return new FilterStates {
@@ -216,7 +231,13 @@ namespace mbts.spark {
            working_bid_volume = working_bid_volume_filter.get_state(),
            working_ask_volume = working_ask_volume_filter.get_state(),
            volume = volume_filter.get_state(),
-            security_key = security_key_filter.get_state()
+            security_key = security_key_filter.get_state(),
+            market_description = market_description_filter.get_state(),
+            cleared_alias = cleared_alias_filter.get_state(),
+            product_description = product_description_filter.get_state(),
+            hub_alias = hub_alias_filter.get_state(),
+            strip_name = strip_name_filter.get_state(),
+            mic_code = mic_code_filter.get_state(),
         };
      }
      #endregion
@@ -8,7 +8,9 @@ namespace mbts.ui.spark {
   /// Interaction logic for MarketSheetsView.xaml
   /// </summary>
   partial class MarketViewView : UserControl {
-      public enum Columns { Security, Volume, Last, LastSize, Position, WorkingBids, Bid, BidMergedSize, BidDirectSize, BidImpliedSize, Ask, AskMergedSize, AskDirectSize, AskImpliedSize, WorkingAsks, Settlement, DayChange, SessionLow, SessionHigh, SecurityKey }
+      public enum Columns { Security, Volume, Last, LastSize, Position, WorkingBids, Bid, BidMergedSize, BidDirectSize, BidImpliedSize, Ask, AskMergedSize, AskDirectSize, AskImpliedSize, WorkingAsks, Settlement, DayChange, SessionLow, SessionHigh, SecurityKey,
+         MarketDescription, ClearedAlias, ProductDescription, HubAlias, StripName, MicCode
+      }

      public MarketViewView() {
         InitializeComponent();
@@ -16,7 +16,7 @@ using System.Windows;

 namespace mbts.spark {
   class MarketViewWindow : SparkWindow<MarketViewWindowFactory.StartupData>, ISharedWindow {
-      const string _window_type = "MarketView", _thread_id = "MarketView", _window_type_display_name = "Market View";
+      const string _window_type = "MarketView", _window_type_display_name = "Market View";
      readonly OrdersModel _orders_model;
      readonly AllowOnce _init_guard = new AllowOnce("MarketView");
      readonly IWindowSettingsManager<GridSettings> _settings_manager;
@@ -32,6 +32,7 @@ namespace mbts.spark {
         _state = state;
         _settings_manager = settings_manager;
         Icon.Freeze();
+         thread_id = config.Configuration.get<bts.config.MultiThreadedWindows>().market_view ? "MarketView" : null;
      }

      event Action<MarketViewWindowFactory.StartupData> _state_changed;
@@ -47,7 +48,7 @@ namespace mbts.spark {
         + LAUNCHER_BUTTON_BORDER_WIDTH
         + EXTRA_FOR_NO_HORIZONTAL_SCROLLBAR_WIDTH;

-      public string thread_id => _thread_id;
+      public string thread_id { get; }

      public void thread_init() {
         _init_guard.check_access();
@@ -97,6 +97,12 @@ namespace bts.shell {
            public static GridColumnSettings session_low => new GridColumnSettings(col_id(Columns.SessionLow), DefaultColumnHeaders.SessionLow, width: DefaultColumnWidths.Price, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
            public static GridColumnSettings session_high => new GridColumnSettings(col_id(Columns.SessionHigh), DefaultColumnHeaders.SessionHigh, width: DefaultColumnWidths.Price, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
            public static GridColumnSettings security_key => new GridColumnSettings(col_id(Columns.SecurityKey), DefaultColumnHeaders.SecurityKey, is_visible: false, width: DefaultColumnWidths.SecurityKey);
+            public static GridColumnSettings market_description => new GridColumnSettings(col_id(Columns.MarketDescription), DefaultColumnHeaders.MarketDescription, is_visible: false, width: DefaultColumnWidths.SecurityKey);
+            public static GridColumnSettings cleared_alias => new GridColumnSettings(col_id(Columns.ClearedAlias), DefaultColumnHeaders.ClearedAlias, is_visible: false, width: DefaultColumnWidths.SecurityKey);
+            public static GridColumnSettings product_description => new GridColumnSettings(col_id(Columns.ProductDescription), DefaultColumnHeaders.ProductDescription, is_visible: false, width: DefaultColumnWidths.SecurityKey);
+            public static GridColumnSettings hub_alias => new GridColumnSettings(col_id(Columns.HubAlias), DefaultColumnHeaders.HubAlias, is_visible: false, width: DefaultColumnWidths.SecurityKey);
+            public static GridColumnSettings strip_name => new GridColumnSettings(col_id(Columns.StripName), DefaultColumnHeaders.StripName, is_visible: false, width: DefaultColumnWidths.SecurityKey);
+            public static GridColumnSettings mic_code => new GridColumnSettings(col_id(Columns.MicCode), DefaultColumnHeaders.MicCode, is_visible: false, width: DefaultColumnWidths.SecurityKey);



@@ -128,6 +134,12 @@ namespace bts.shell {
                  yield return session_low;
                  yield return session_high;
                  yield return security_key;
+                  yield return market_description;
+                  yield return cleared_alias;
+                  yield return product_description;
+                  yield return hub_alias;
+                  yield return strip_name;
+                  yield return mic_code;
               }
            }

@@ -177,6 +189,18 @@ namespace bts.shell {
         public UIntMinMaxState ask_direct_size;
         [ProtoMember(20)]
         public UIntMinMaxState ask_implied_size;
+         [ProtoMember(21)]
+         public string market_description;
+         [ProtoMember(22)]
+         public string cleared_alias;
+         [ProtoMember(23)]
+         public string product_description;
+         [ProtoMember(24)]
+         public string hub_alias;
+         [ProtoMember(25)]
+         public string strip_name;
+         [ProtoMember(26)]
+         public string mic_code;
      }
   }
 }
@@ -19,7 +19,7 @@ using static bts.shell.TimeAndSalesWindowFactory;
 using static mbts.ui.controls.DIYGrid;

 namespace mbts.spark {
-   class TimeAndSalesWindow : SparkWindow<StartupData>, ISlowWindow {
+   class TimeAndSalesWindow : SparkWindow<StartupData>, ISharedWindow {
      const string _window_type = "TimeAndSales", _window_type_display_name = "Time And Sales";
      readonly MDConsumer _consumer;
      readonly TimeAndSalesWindowFactory _factory;
@@ -48,7 +48,7 @@ namespace mbts.spark {
         + SPARK_MENU_COLLAPSED_WIDTH
         + LAUNCHER_BUTTON_BORDER_WIDTH
         + EXTRA_FOR_NO_HORIZONTAL_SCROLLBAR_WIDTH;
-      
+      public string thread_id { get; }
      public override StartupData SaveState => _state = _vm.value.create();

      public override void Dispose() =>
@@ -16,7 +16,7 @@ using System.Windows;
 using static bts.shell.SyntheticManagementWindowFactory;

 namespace mbts.spark {
-   class SyntheticManagementWindow : SparkWindow<StartupData>, ISlowWindow {
+   class SyntheticManagementWindow : SparkWindow<StartupData>, ISharedWindow {
      const string _window_type = "SyntheticManagement";
      SingleValuePump<SyntheticManagementDialogVM> _vm = new SingleValuePump<SyntheticManagementDialogVM>();
      StartupData _state;
@@ -33,8 +33,20 @@ namespace mbts.spark {
         _state = state;
         _settings_manager = settings_manager;
         Icon.Freeze();
+         thread_id = config.Configuration.get<bts.config.MultiThreadedWindows>().synthetic_management ? "SyntheticManagement" : null;
      }

+      public override string window_type => _window_type;
+      public override UIElement Content => _view;
+      public override IEnumerable<SparkCommand> Commands => _commands;
+      public override StartupData SaveState => _state = _vm.value.create();
+      public override double MinWidth => 
+         StartupData.DefaultGridSettings.columns.Sum(gcs => gcs.width)
+         + SPARK_MENU_COLLAPSED_WIDTH
+         + LAUNCHER_BUTTON_BORDER_WIDTH
+         + EXTRA_FOR_NO_HORIZONTAL_SCROLLBAR_WIDTH;
+      public string thread_id { get; }
+
      public void thread_init() {
         Log.notnull(_state);

@@ -101,16 +113,6 @@ namespace mbts.spark {
         else _view.DataContext = _vm.value;
      }

-      public override string window_type => _window_type;
-      public override UIElement Content => _view;
-      public override IEnumerable<SparkCommand> Commands => _commands;
-      public override StartupData SaveState => _state = _vm.value.create();
-      public override double MinWidth => 
-         StartupData.DefaultGridSettings.columns.Sum(gcs => gcs.width)
-         + SPARK_MENU_COLLAPSED_WIDTH
-         + LAUNCHER_BUTTON_BORDER_WIDTH
-         + EXTRA_FOR_NO_HORIZONTAL_SCROLLBAR_WIDTH;
-
      public override void Dispose() {
         Disposable.dispose(ref _vm);
         Commands.OfType<IDisposable>().DisposeAll();
@@ -19,8 +19,6 @@
    <ResourceDictionary>
      <ResourceDictionary.MergedDictionaries>
        <ResourceDictionary Source="/view/Controls/Order/AlgoTemplateTreeView.xaml"/>
-        <ResourceDictionary Source="/view/Controls/Order/AlgoPickerNodeView.xaml"/>
-        <ResourceDictionary Source="/view/Controls/Order/AlgoContentTemplateSelector.xaml"/>
      </ResourceDictionary.MergedDictionaries>
      <!--Primitive Constants-->
      <sys:Double x:Key="HorizontalPush1">4</sys:Double>
@@ -559,71 +557,14 @@
              </Grid>
            </RadioButton>
          </Grid>
-          <GroupBox
-            x:Name="content_host"
+          <usp:AlgoEditorView
            Grid.Row="2"
+            DataContext="{Binding content_source}"
            Background="Transparent"
-            BorderBrush="{Binding content_source.algo_root, Converter={StaticResource OrderTypeBrushConverter}}"
+            BorderBrush="{Binding algo_root, Converter={StaticResource OrderTypeBrushConverter}}"
            Margin="0,6,0,0"
            Padding="12,8"
-          >
-            <GroupBox.Style>
-              <Style TargetType="GroupBox" BasedOn="{StaticResource ContentHostGroupBoxStyle}">
-                <Setter Property="BorderThickness" Value="1"/>
-                <Setter Property="BorderBrush" Value="Transparent"/>
-                <Style.Triggers>
-                  <Trigger Property="BorderBrush" Value="Transparent">
-                    <Setter Property="BorderThickness" Value="0"/>
-                  </Trigger>
-                  <Trigger Property="usp:AlgoStudioView.IsMouseOverNodeContent" Value="True">
-                    <Setter Property="BorderThickness" Value="2"/>
-                  </Trigger>
-                </Style.Triggers>
-              </Style>
-            </GroupBox.Style>
-            <GroupBox.Header>
-              <ComboBox
-                Grid.Column="3"
-                ToolTipService.ShowOnDisabled="True"
-                SelectedItem="{Binding selected_definition.algo_root}"
-                ItemsSource="{Binding selected_definition.algos_view}"
-                Margin="{StaticResource Margin.LP1}"
-                Width="140"
-              >
-                <ComboBox.Style>
-                  <Style TargetType="ComboBox">
-                    <Style.Triggers>
-                      <DataTrigger Binding="{Binding content_source}" Value="{x:Null}">
-                        <Setter Property="Visibility" Value="Collapsed"/>
-                      </DataTrigger>
-                      <DataTrigger Binding="{Binding selected_definition.templates.Count, Converter={StaticResource IntIsZeroConverter}, FallbackValue={u:False}}" Value="{u:True}">
-                        <Setter Property="IsEnabled" Value="True"/>
-                      </DataTrigger>
-                      <DataTrigger Binding="{Binding selected_definition.templates.Count, Converter={StaticResource IntIsZeroConverter}, FallbackValue={u:False}}" Value="{u:False}">
-                        <Setter Property="IsEnabled" Value="False"/>
-                        <Setter Property="ToolTip" Value="Cannot change structure while templates are present."/>
-                      </DataTrigger>
-                    </Style.Triggers>
-                  </Style>
-                </ComboBox.Style>
-                <ComboBox.ItemTemplate>
-                  <DataTemplate>
-                    <usp:OrderTypeItem DisplayName="{Binding display_name}" BadgeFill="{Binding meta.Color, Converter={StaticResource ColorToBrushConverter}}"/>
-                  </DataTemplate>
-                </ComboBox.ItemTemplate>
-              </ComboBox>
-            </GroupBox.Header>
-            <ContentControl
-              Grid.IsSharedSizeScope="True"
-              Content="{Binding selected_definition.algo_root}"
-              ContentTemplateSelector="{StaticResource AlgoTemplateSelector}"
-              Margin="{StaticResource Margin.TP1}"
-            >
-              <ContentControl.Resources>
-                <Style TargetType="GroupBox" BasedOn="{StaticResource ContentHostGroupBoxStyle}"/>
-              </ContentControl.Resources>
-            </ContentControl>
-          </GroupBox>
+          />
          <c:DialogSkirt Grid.Row="3" Margin="{StaticResource Margin.TP2}" Background="Transparent">
            <c:DialogSkirt.RightItems>
              <x:ArrayExtension Type="{x:Type Button}">
@@ -1,8 +1,6 @@
 using mbts.spark;
 using mbts.ui.converters;
-using mbts.ui.extensions;
 using System;
-using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Data;
 using System.Windows.Input;
@@ -18,26 +16,11 @@ namespace mbts.ui.spark {
      public AlgoStudioView() {
         InitializeComponent();
         DataContextChanged += (s, e) => set_controller();
-         content_host.PreviewMouseMove += content_host_PreviewMouseMove;
-         content_host.MouseEnter += content_host_MouseEnter;
-         content_host.MouseLeave += content_host_MouseLeave;
         set_controller();
         // local methods
         void set_controller() => Disposable.replace(ref _controller, AlgoStudioViewControllerFactory.create(DataContext, _tree_view, name_text_box, custom_badge_color_picker_button, custom_badge_color_picker_popup));
-         void content_host_PreviewMouseMove(object sender, MouseEventArgs e) => refresh_is_mouse_over_content_host(e);
-         void content_host_MouseEnter(object sender, MouseEventArgs e) => refresh_is_mouse_over_content_host(e);
-         void content_host_MouseLeave(object sender, MouseEventArgs e) => refresh_is_mouse_over_content_host(e);
-         void refresh_is_mouse_over_content_host(MouseEventArgs e) => content_host.set_current_if_changed(IsMouseOverNodeContentProperty, this.ChildAtPoint<GroupBox>(e.GetPosition(this)) == content_host);
      }

-      #region IsMouseOverNodeContent 
-      public static readonly DependencyProperty IsMouseOverNodeContentProperty =
-         DependencyProperty.RegisterAttached("IsMouseOverNodeContent", typeof(bool), typeof(AlgoStudioView), new PropertyMetadata(false));
-
-      public static bool GetIsMouseOverNodeContent(DependencyObject d) => (bool)d.GetValue(IsMouseOverNodeContentProperty);
-      public static void SetIsMouseOverNodeContent(DependencyObject d, bool value) => d.SetValue(IsMouseOverNodeContentProperty, value);
-      #endregion
-
      public new AlgoStudioVM DataContext {
         get => base.DataContext as AlgoStudioVM;
         set => base.DataContext = value;
@@ -13,7 +13,7 @@ using System.Windows;
 using StartupData = bts.shell.AlgoStudioWindowFactory.StartupData;

 namespace mbts.spark {
-   internal class AlgoStudioWindow : SparkWindow<StartupData>, IShellWindow {
+   internal class AlgoStudioWindow : SparkWindow<StartupData>, ISharedWindow {
      public const string
         NAME = "Algo Studio",
         TemplatesEnabledKey = nameof(TemplatesEnabledKey),
@@ -37,7 +37,7 @@ namespace mbts.spark {
         : base(NAME, bus, factory, SparkCommands.ShowAlgoStudio.icon) {
         _model = model;
         _state = state;
-         thread_init();
+         thread_id = config.Configuration.get<bts.config.MultiThreadedWindows>().algo_studio ? "AlgoStudio" : null;
      }

      public override StartupData SaveState => _state = _vm.create();
@@ -45,12 +45,12 @@ namespace mbts.spark {
      public override string window_type => NAME;
      public override UIElement Content => _view;
      public override IEnumerable<SparkCommand> Commands => _commands;
-      public string thread_id => NAME;
      public override double MinWidth =>
         SPARK_MENU_COLLAPSED_WIDTH +
         LAUNCHER_BUTTON_BORDER_WIDTH +
         DEFAULT_CONTENT_WIDTH;
      public override double MinHeight => DEFAULT_CONTENT_HEIGHT;
+      public string thread_id { get; }

      bts.config.AlgoStudioOptions _ui_configuration => _model.algo_model.ui_configuration;

@@ -1,8 +1,9 @@
 using bts.api.orderman;
 using bts.utils;
 using mbts.spark.utilities;
-using ProtoBuf;
+using mbts.ui.utility;
 using System;
+using System.Collections.Generic;
 using System.Linq;

 namespace mbts.spark {
@@ -10,12 +11,6 @@ namespace mbts.spark {
      public readonly string name;
      public readonly AlgoStructureKey structure;

-      public AlgoNameStructureKey(CustomOrderDefinitionImmutable definition)
-         : this(definition.CustomCase.type_id(), definition) { }
-
-      public AlgoNameStructureKey(string name, CustomOrderDefinitionImmutable definition)
-         : this(name, new AlgoStructureKey(definition)) { }
-
      public AlgoNameStructureKey(CustomOrderDefinition.CustomOneofCase base_type)
         : this(base_type.type_id(), new AlgoStructureKey(base_type)) { }

@@ -31,31 +26,22 @@ namespace mbts.spark {
      public static bool operator !=(AlgoNameStructureKey a, AlgoNameStructureKey b) => !a.Equals(b);
   }

-   [ProtoContract]
   struct AlgoStructureKey : IEquatable<AlgoStructureKey> {
-      [ProtoMember(1)]
      readonly int[] _structure;

      public AlgoStructureKey(CustomOrderDefinition.CustomOneofCase base_type)
         : this(new[] { (int)base_type }) { }

-      public AlgoStructureKey(CustomOrderDefinitionImmutable definition) {
-         int[] s = new[] { (int)definition.CustomCase };
-         _build_structure(definition, ref s, 1);
-         _structure = s;
-      }
+      public AlgoStructureKey(CustomOrderDefinitionImmutable definition, IMaskIndexInt32<string> dynamic_type_index) =>
+         _structure = AlgoStructureSerializer.to_array(definition, dynamic_type_index);

      public AlgoStructureKey(int[] structure) =>
         _structure = structure;

-      public CustomOrderDefinitionImmutable build_def() {
-         int pos = 0;
-         var mdef = new CustomOrderDefinition();
-         _build_def(_structure, ref pos, ref mdef);
-         return new CustomOrderDefinitionImmutable(mdef);
-      }
+      public IReadOnlyList<int> structure => _structure ?? Array.Empty<int>();

      public bool Equals(AlgoStructureKey other) =>
+         /// <see cref="Enumerable.SequenceEqual{TSource}(IEnumerable{TSource}, IEnumerable{TSource})"/> is not optimized to check Count/Length, since the args are <see cref="IEnumerable{T}"/>.
         _structure.Length == other._structure.Length &&
         _structure.SequenceEqual(other._structure);

@@ -67,35 +53,105 @@ namespace mbts.spark {

      public static bool operator ==(AlgoStructureKey a, AlgoStructureKey b) => a.Equals(b);
      public static bool operator !=(AlgoStructureKey a, AlgoStructureKey b) => !a.Equals(b);
+   }

-      static void _build_structure(CustomOrderDefinitionImmutable definition, ref int[] structure, int pos) =>
-         _build_structure(definition.CloneToMutable(), ref structure, pos);
+   static class AlgoStructureSerializer {
+      const int
+         _dynamic_mask = 1 << 31,
+         _child_mask_offset = 30;

-      static void _build_structure(CustomOrderDefinition algo, ref int[] structure, int pos) {
-         var cad = OrderDataHelper.get_child_algo_data(algo);
-         for (int di = 0; di < cad.Count; di++) {
-            if (cad[di].get_child(algo) is CustomOrderDefinition child_algo) { 
-               ArrayHelper.ensure_capacity(ref structure, pos + 1);
-               int del_mask = 1 << (31 - di);
-               structure[pos++] = (int)child_algo.CustomCase | del_mask;
-               _build_structure(child_algo, ref structure, pos);
-               break;
-            }
-         }
-         ArrayHelper.trim(ref structure, pos);
+      public static CustomOrderDefinitionImmutable build_algoi(this AlgoStructureKey structure_key, DynamicOrderHelper dynamic_helper) =>
+         parsei(structure_key.structure, dynamic_helper);
+
+      public static CustomOrderDefinitionImmutable build_algo(this AlgoStructureKey structure_key, DynamicOrderHelper dynamic_helper) =>
+         parsei(structure_key.structure, dynamic_helper);
+
+      public static AlgoStructureKey structure_key(CustomOrderDefinitionImmutable algo, IMaskIndexInt32<string> dynamic_type_index) =>
+         new AlgoStructureKey(to_array(algo, dynamic_type_index));
+
+      public static AlgoStructureKey structure_key(CustomOrderDefinition algo, IMaskIndexInt32<string> dynamic_type_index) =>
+         new AlgoStructureKey(to_array(algo, dynamic_type_index));
+
+      public static int[] to_array(CustomOrderDefinitionImmutable algo, IMaskIndexInt32<string> dynamic_type_index) =>
+         to_array(algo.CloneToMutable(), dynamic_type_index);
+
+      public static int[] to_array(CustomOrderDefinition algo, IMaskIndexInt32<string> dynamic_type_index) {
+         int[] s = new[] { (int)algo.CustomCase };
+         _build_structure(algo, ref s, dynamic_type_index);
+         return s;
      }

-      static void _build_def(int[] structure, ref int pos, ref CustomOrderDefinition algo) {
-         for (int i = pos; i < structure.Length; i++) {
+      public static CustomOrderDefinitionImmutable from_array(int[] structure, DynamicOrderHelper dynamic_helper) =>
+         parsei(structure, dynamic_helper);
+
+      public static CustomOrderDefinitionImmutable parsei(IReadOnlyList<int> structure, DynamicOrderHelper dynamic_helper) =>
+         new CustomOrderDefinitionImmutable(parse(structure, dynamic_helper));
+
+      public static CustomOrderDefinition parse(IReadOnlyList<int> structure, DynamicOrderHelper dynamic_helper) {
+         if (structure == null || structure.Count == 0)
+            return new CustomOrderDefinition();
+         int pos = 1;
+         var mdef = OrderDataHelper.create_algo((CustomOrderDefinition.CustomOneofCase)structure[0]);
+         _build_def(structure, ref pos, ref mdef, dynamic_helper);
+         return mdef;
+      }
+
+      static void _build_structure(CustomOrderDefinition algo, ref int[] structure, IMaskIndexInt32<string> dynamic_type_index) {
+         if (structure == null || structure.Length == 0)
+            structure = new int[1];
+         structure[0] = (int)algo.CustomCase;
+         int p = 1;
+         _build_structure(algo, ref structure, ref p, dynamic_type_index);
+         ArrayHelper.trim(ref structure, p);
+      }
+
+      static void _build_structure(CustomOrderDefinition algo, ref int[] structure, ref int pos, IMaskIndexInt32<string> dynamic_type_index) {
+         IEnumerable<(CustomOrderDefinition child_algo, int field_pos)> children;
+         if (algo.CustomCase == CustomOrderDefinition.CustomOneofCase.Dynamic) {
+            ArrayHelper.ensure_capacity(ref structure, pos + 1);
+            structure[pos++] = dynamic_type_index.to_int(algo.Dynamic.DynamicOrderType) | _dynamic_mask;
+            children = algo.Dynamic.OrderParams.Where(kv => kv.Value.ValueCase == DynamicOrderParam.ValueOneofCase.AsOrderDef).Select((kv, i) => (kv.Value.AsOrderDef, i));
+         } else {
            var cad = OrderDataHelper.get_child_algo_data(algo);
-            for (int di = 0; di < cad.Count; di++) {
-               int mask = 1 << (31 - di);
-               if ((structure[i] & mask) == mask) {
-                  var type = (CustomOrderDefinition.CustomOneofCase)(structure[i] ^ mask);
-                  var child_algo = OrderDataHelper.Defaults.CustomOrderDefinition(type);
-                  pos++;
-                  _build_def(structure, ref pos, ref child_algo);
-                  cad[di].assign_child(algo, child_algo);
+            children = cad.Select((c, i) => (c.get_child(algo), i));
+            children = children.Where(c => c.child_algo != null);
+         }
+         foreach ((var child, int field_pos) in children) {
+            ArrayHelper.ensure_capacity(ref structure, pos + 1);
+            structure[pos++] = EnumMaskIndexInt32<CustomOrderDefinition.CustomOneofCase>.to_int(child.CustomCase) | _child_algo_mask(field_pos);
+            _build_structure(child, ref structure, ref pos, dynamic_type_index);
+         }
+      }
+
+      /// <summary>
+      /// Gets a mask for a particular child-algo field of a particular algo definition.
+      /// </summary>
+      /// <param name="field_pos">The index wrt the deterministic enumeration of child algos for a particular definition (e.g., Hedge = 0, Child = 1).</param>
+      static int _child_algo_mask(int field_pos) => 1 << (_child_mask_offset - field_pos);
+
+      static void _build_def(IReadOnlyList<int> structure, ref int pos, ref CustomOrderDefinition algo, DynamicOrderHelper dynamic_helper) {
+         var local_algo = algo;
+         IEnumerable<(Action<CustomOrderDefinition> assign_child, int field_pos)> children;
+         if (algo.CustomCase == CustomOrderDefinition.CustomOneofCase.Dynamic) {
+            var dyn_def = algo.Dynamic;
+            dyn_def.DynamicOrderType = dynamic_helper.dynamic_type_index.from_int(structure[pos++] ^ _dynamic_mask);
+            dynamic_helper.add_dynamic_params(ref dyn_def);
+            children = dyn_def.OrderParams
+               .Where(kv => kv.Value.ValueCase == DynamicOrderParam.ValueOneofCase.AsOrderDef)
+               .Select((kv, i) => (new Action<CustomOrderDefinition>(child_algo => kv.Value.AsOrderDef = child_algo), i));
+         } else {
+            children = OrderDataHelper.get_child_algo_data(algo)
+               .Select((c, i) => (new Action<CustomOrderDefinition>(child_algo => c.assign_child(local_algo, child_algo)), i));
+         }
+         using (var children_en = children.GetEnumerator()) {
+            while (pos < structure.Count && children_en.MoveNext()) {
+               (var assign_child, int field_pos) = children_en.Current;
+               int mask = _child_algo_mask(field_pos);
+               if ((structure[pos] & mask) == mask) {
+                  var type = EnumMaskIndexInt32<CustomOrderDefinition.CustomOneofCase>.from_int(structure[pos++] ^ mask);
+                  var child_algo = OrderDataHelper.create_algo(type);
+                  _build_def(structure, ref pos, ref child_algo, dynamic_helper);
+                  assign_child(child_algo);
               }
            }
         }
@@ -34,6 +34,18 @@ namespace mbts.spark {
         }
      }

+      public static void update_persisted_definition_wrappers(ObservableKeyedCollection<IAlgoVM, AlgoKey> target, TableUpdate<AlgoData, AlgoKey> update, Func<AlgoData, AlgoDefinitionVM> factory) {
+         foreach (var d in update.removed)
+            target.Remove(d.key);
+         foreach (var d in update.changed)
+            target[d.key].load_from(d.value);
+         foreach (var d in update.added) {
+            if (target.TryGetValue(d.key, out IAlgoVM def)) {
+               def.load_from(d.value);
+            } else target.Add(new AlgoVMWrapper(factory(d)));
+         }
+      }
+
      static class _CompareUtils {
         public static int compare_modes(AlgoDefinitionVM a, AlgoDefinitionVM b) =>
            _compare_modes(a.key.mode, b.key.mode);
@@ -46,7 +46,8 @@ namespace mbts.spark {
      readonly DeferrableActionWrapper _refresh_on_local_changes;
      readonly ReactiveThresholdMonitor<AlgoDefinitionTemplateVM> _any_templates_dirty_monitor = new ReactiveThresholdMonitor<AlgoDefinitionTemplateVM>(t => t.observe_is_dirty());
      readonly Property<AlgoFormats> _selected_format;
-      AlgoEditingPermissions _editing_permissions;
+      readonly EnumMaskInt32<AlgoEditingPermissions> _permissions_mask = new EnumMaskInt32<AlgoEditingPermissions>();
+
      int? _favorite_index;
      Brush _badge_fill;
      Snapshot? _committed;
@@ -54,29 +55,43 @@ namespace mbts.spark {
      TableUpdateBuffer<AlgoTemplateData, AlgoKey> _template_update_buffer;
      bool _connected;

-      public static AlgoDefinitionVM create(OrdersModel model, AlgoData data, bool connect = false, AlgoFormats init_format = AlgoFormats.Exchange) {
-         var rv = new AlgoDefinitionVM(model, data, init_format);
+      public static AlgoDefinitionVM create(OrdersModel model, AlgoData data, bool connect = false, AlgoFormats init_format = AlgoFormats.Exchange, AlgoEditingPermissions editing_permissions = (AlgoEditingPermissions)int.MaxValue) {
+         var rv = new AlgoDefinitionVM(model, data, init_format, editing_permissions);
         if (connect)
            rv.connect();
         return rv;
      }

      public static AlgoDefinitionVM create_placeholder(OrdersModel model, CustomOrderDefinitionImmutable def, string name, AlgoFormats init_format) =>
-         new AlgoDefinitionVM(model, new AlgoData(def, name, new AlgoKey(Guid.NewGuid())), init_format);
+         new AlgoDefinitionVM(model, new AlgoData(def, name, new AlgoKey(Guid.NewGuid())), init_format, (AlgoEditingPermissions)int.MaxValue);

-      AlgoDefinitionVM(OrdersModel model, AlgoData def_data, AlgoFormats init_format = AlgoFormats.Exchange) {
+      AlgoDefinitionVM(OrdersModel model, AlgoData def_data, AlgoFormats init_format, AlgoEditingPermissions init_permissions) {
         // init core data
         _model = model;
+         _permissions_mask.mask = init_permissions;
+         _permissions_mask.raw = init_permissions;
+         var resources = new CompositeDisposable();
+         if (!model.algo_model.ui_configuration.can_modify_definition_values)
+            editing_permissions_mask ^= (AlgoEditingPermissions.AllowEditValues | AlgoEditingPermissions.AllowSaveValues);
+         if (!model.algo_model.ui_configuration.can_modify_definition_structure)
+            editing_permissions_mask ^= (AlgoEditingPermissions.AllowEditStructure | AlgoEditingPermissions.AllowSaveStructure);
+         else if (model.algo_model.templates_enabled()) {
+            resources.Add(_templates.Subscribe((s, e) => {
+               if (_templates.Count == 0) {
+                  editing_permissions_mask |= AlgoEditingPermissions.AllowEditStructure | AlgoEditingPermissions.AllowSaveStructure;
+               } else {
+                  editing_permissions_mask ^= (AlgoEditingPermissions.AllowEditStructure | AlgoEditingPermissions.AllowSaveStructure);
+               }
+            }));
+         }
         key = def_data.key;
         algos_view = ObservableAutoWrapper.create_sorted_wrapper(_algo_roots, AlgoCollectionHelper.algo_vm_comparer);
         _template_update_buffer = new TableUpdateBuffer<AlgoTemplateData, AlgoKey>(t => t.key);
         _templates_with_custom = new ObservableAppendCollection<AlgoDefinitionTemplateVM>(templates);
         templates_view = (ListCollectionView)CollectionViewSource.GetDefaultView(_templates_with_custom);
         custom_badge_color_palettes.AddRange(ColorPalette.all_presets(model.factory).Select(p => new ColorPaletteVM(p)));
-         _editing_permissions = _get_permissions();
         _version = new VersionContainer<Snapshot>(_snapshot);
         var conf = _model.algo_model.ui_configuration;
-         var resources = new CompositeDisposable();
         // init backing props
         _name = backing(nameof(name), def_data.name);
         _abbreviation = backing(nameof(abbreviation), string.Empty);
@@ -87,7 +102,7 @@ namespace mbts.spark {
         _is_selected = backing(nameof(is_selected), true);
         _is_dirty = backing(nameof(is_dirty), () => key.mode == AlgoKey.Mode.Unpersisted || !_committed.HasValue || !_committed.Value.Equals(_version.value));
         var factory_def_data = def_data.key.mode == AlgoKey.Mode.Factory ? def_data : new AlgoData(def_data.value);
-         _algo_root = backing(nameof(algo_root), _algo_roots.GetOrAdd(factory_def_data.key, _ => OrderTypeVMFactory.create(factory_def_data, _editing_permissions)));
+         _algo_root = backing(nameof(algo_root), _algo_roots.GetOrAdd(factory_def_data.key, _ => OrderTypeVMFactory.create(factory_def_data)));
         _visible_algo_root = backing<IAlgoVM>(nameof(visible_algo_root));
         _can_redo = backing(nameof(can_redo), () => _edit_stack.get_can_redo(_version.value));
         _can_undo = backing(nameof(can_undo), () => _edit_stack.get_can_undo(_version.value));
@@ -113,7 +128,6 @@ namespace mbts.spark {
                  as_demuxer().subscribe_many(_refresh_on_local_changes.execute, nameof(this.name), nameof(abbreviation), nameof(badge_fill)),
                  _edit_pane_vs_model.add_source(VisualStateNames.BadgeSelector.GroupName, custom_badge_color.observe_nullable(true).Select(t => t.HasValue ? VisualStateNames.BadgeSelector.Active : VisualStateNames.BadgeSelector.Inactive)),
                  _edit_pane_vs_model.add_source(VisualStateNames.Abbreviation.GroupName, _abbreviation.observe_current(true).Select(a => string.IsNullOrEmpty(a) ? VisualStateNames.Abbreviation.Unpopulated : VisualStateNames.Abbreviation.Populated)),
-                  templates.ObserveSelf().Select(_ => _get_permissions()).DistinctUntilChanged().OnDispatcher().Subscribe(on_editing_permissions),
                  _algo_root.observe_current(true).SubscribeHookLatest(vm => {
                     if (vm == null)
                        return Disposable.empty;
@@ -152,16 +166,22 @@ namespace mbts.spark {
                     _edit_pane_vs_model.set_state(VisualStateNames.Name.GroupName, VisualStateNames.Name.Inactive);
                     break;
               }
-               resources.Add(_selected_format.observe_current(true).SubscribeHookLatest(f => {
-                  using (_refresh_on_local_changes.defer_execution()) {
-                     var algo_data = model.factory.default_algos(f);
-                     var default_algo = new AlgoKey(OrderDataHelper.get_default_algo(f));
-                     return this.load_algo_data_recursive(algo_data, default_algo);
-                  }
-               }));
+               var permission_src = _permissions_mask.observe_result();
+               resources.Add(_selected_format.observe_current(true).CombineLatest(permission_src, (fmt, perms) => (fmt, perms))
+                  .SubscribeHookLatest(t => {
+                     if ((t.perms & AlgoEditingPermissions.AllowEditStructure) != 0) {
+                        using (_refresh_on_local_changes.defer_execution()) {
+                           var algo_data = model.factory.default_algos(t.fmt);
+                           var default_algo = new AlgoKey(OrderDataHelper.get_default_algo(t.fmt));
+                           return this.load_algo_data_recursive(algo_data, default_algo);
+                        }
+                     }
+                     return Disposable.empty;
+                  }));
+               resources.Add(permission_src.Subscribe(_ => RaisePropertyChanged(nameof(editing_permissions))));
+               resources.Add(this.connect_data(permission_src));
               resources.Add(this.connect_data(Observable.Return(model)));
               _dispose = resources;
-               on_editing_permissions(_get_permissions());
               await algo_root.load_from_async(def_data.value);
               _version.increment_version();
               _edit_stack.reset(_version.value);
@@ -169,11 +189,6 @@ namespace mbts.spark {
            }
         }
         // local methods
-         void on_editing_permissions(AlgoEditingPermissions eps) {
-            _editing_permissions = eps;
-            foreach (var vm in algo_roots)
-               vm.set_permissions(eps);
-         }
         void on_can_redo_changed(bool oldval, bool newval) => can_redo_changed?.Invoke();
         void on_can_undo_changed(bool oldval, bool newval) => can_undo_changed?.Invoke();
         void on_local_changed() {
@@ -230,6 +245,9 @@ namespace mbts.spark {
      // visual states
      public ObservableCollection<string> edit_pane_visual_states => _edit_pane_vs_model.states;
      public ObservableCollection<string> tree_view_visual_states => _tree_view_vs_model.states;
+      // editing permissions
+      public AlgoEditingPermissions editing_permissions_mask { get => _permissions_mask.mask; set => _permissions_mask.mask = value; }
+      public AlgoEditingPermissions editing_permissions => _permissions_mask.result;

      #region IAlgoSelector
      event PropertyChange<IAlgoVM> IAlgoSelector.selected_algo_changed { add => algo_root_changed += value; remove => algo_root_changed -= value; }
@@ -248,7 +266,7 @@ namespace mbts.spark {

      void _load_algo_data(IReadOnlyDictionary<AlgoKey, AlgoData> algo_data, AlgoKey? default_algo) {
         var orig_algo = algo_root?.id;
-         _algo_roots.SyncWithDictionary(algo_data, d => OrderTypeVMFactory.create(d, _editing_permissions, true));
+         _algo_roots.SyncWithDictionary(algo_data, d => OrderTypeVMFactory.create(d, is_expanded: true));
         if (!try_select(orig_algo) && !try_select(default_algo))
            algo_root = algo_roots.FirstOrDefault();
         //
@@ -298,6 +316,19 @@ namespace mbts.spark {

      public IDisposable buffer_updates() => _template_update_buffer.buffer_updates();

+      public void load_def(CustomOrderDefinitionImmutable def) {
+         var key = OrderDataHelper.get_shallow_factory_key(def);
+         if (algo_root?.id == key) {
+            algo_root.load_from(def);
+         } else if (_algo_roots.TryGetValue(key, out IAlgoVM vm)) {
+            vm.load_from(def);
+            algo_root = vm;
+         } else {
+            algo_roots.Add(vm = _mk_algo_root(def));
+            algo_root = vm;
+         }
+      }
+
      public void load(AlgoData data) {
         _assert_can_load(data.key);
         if (algo_root != null)
@@ -309,7 +340,7 @@ namespace mbts.spark {

      // pass a copy of the persisted state - rather than use local values - because if something goes wrong, it is better to be in sync with data fresh from the server/api.
      public AlgoDefinitionVM to_persisted(AlgoData def) =>
-         new AlgoDefinitionVM(_model, def);
+         new AlgoDefinitionVM(_model, def, selected_format, editing_permissions_mask);

      public AlgoData create_algo_def() =>
         new AlgoData(algo_root.definition, name, key);
@@ -322,16 +353,6 @@ namespace mbts.spark {
      public override int GetHashCode() => key.GetHashCode();
      public override string ToString() => algo_root == null ? $"!:{name}" : $"{algo_root.order_type}:{name}";

-      AlgoEditingPermissions _get_permissions() {
-         var permissions = AlgoEditingPermissions.None;
-         if (_model.algo_model.ui_configuration.can_modify_definition_values) {
-            permissions |= AlgoEditingPermissions.AllowEditValues | AlgoEditingPermissions.AllowSaveValues;
-         }
-         if (_model.algo_model.ui_configuration.can_modify_definition_structure || (_model.algo_model.templates_enabled() && _templates.Count == 0))
-            permissions |= AlgoEditingPermissions.AllowEditStructure | AlgoEditingPermissions.AllowSaveStructure;
-         return permissions;
-      }
-
      void _assert_can_load(AlgoKey data_key) {
         if (key.mode != data_key.mode)
            throw new InvalidOperationException($"{typeof(AlgoDefinitionVM)} '{nameof(key)}.{nameof(AlgoKey.mode)}' must be {data_key.mode} (actually {key.mode}), to load specified data.");
@@ -362,7 +383,7 @@ namespace mbts.spark {
      }

      IAlgoVM _mk_algo_root(CustomOrderDefinitionImmutable definition) =>
-         OrderTypeVMFactory.create(new AlgoData(definition), editing_permissions: _editing_permissions, true);
+         OrderTypeVMFactory.create(new AlgoData(definition), is_expanded: true);

      void _on_metadata(AlgoDefinitionMetadata metadata) {
         using (_refresh_on_local_changes.supress_execution()) {
@@ -0,0 +1,198 @@
+using bts.api;
+using bts.api.orderman;
+using bts.spark;
+using mbts.spark.utilities;
+using mbts.ui;
+using mbts.ui.controls;
+using mbts.ui.shell;
+using mbts.utils;
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Collections.Specialized;
+using System.ComponentModel;
+using System.Reactive.Disposables;
+using System.Reactive.Linq;
+using System.Threading.Tasks;
+using System.Windows.Input;
+
+namespace mbts.spark {
+   class AlgoVMWrapper : DisposableViewModelBase, IAlgoVM,
+      IObserver<SecurityMD?>,
+      IObserver<SecurityImmutable?>,
+      IObserver<OrdersModel>,
+      IObserver<AlgoEditingPermissions> {
+      static readonly HashSet<string>
+         _algo_root_echo_props = new HashSet<string> {
+            nameof(is_expanded),
+            nameof(editing_permissions),
+            nameof(definition),
+            nameof(display_name)
+         },
+         _value_echo_props = new HashSet<string> {
+            nameof(AlgoDefinitionVM.name),
+            nameof(AlgoDefinitionVM.abbreviation),
+            nameof(AlgoDefinitionVM.badge_fill),
+            nameof(AlgoDefinitionVM.can_undo),
+            nameof(AlgoDefinitionVM.can_redo)
+         };
+      readonly ObservableAggregateCollection<IAlgoSelector> _child_algo_selectors = new ObservableAggregateCollection<IAlgoSelector>();
+      readonly DisposableContainer _value_hooks = new DisposableContainer();
+      Action _definition_changed = () => { };
+      _ObservedData? _data_cache;
+      AlgoDefinitionVM _value;
+
+      public AlgoVMWrapper(AlgoDefinitionVM algo_definition_vm) {
+         value = algo_definition_vm;
+         _dispose = new CompositeDisposable(_value_hooks) {
+            _child_algo_selectors.clear_collections,
+            () => _value?.Dispose()
+         };
+      }
+
+      public event Action definition_changed { add => _definition_changed += value; remove => _definition_changed -= value; }
+
+      public AlgoDefinitionVM value {
+         get => _value;
+         set {
+            if (_value != value) {
+               _value?.Dispose();
+               _value = value;
+               _value_hooks.replace(_set_hooks(value));
+               RaisePropertyChanged(nameof(value));
+            }
+         }
+      }
+      public AlgoKey id => _value.key;
+      public CustomOrderDefinition.CustomOneofCase order_type => _algo_root?.order_type ?? CustomOrderDefinition.CustomOneofCase.None;
+      public bool is_bts_type => _algo_root?.is_bts_type ?? false;
+      public OrderMetadata meta {
+         get {
+            if (_value != null) {
+               if (_value.custom_badge_color.enabled)
+                  return new OrderMetadata { Color = value.custom_badge_color.value.rgb_color(), KeyBinding = value.abbreviation.if_null_or_empty(value.name) };
+               else if (_value.algo_root != null)
+                  return _value.algo_root.meta;
+            }
+            return OrderDataHelper.get_metadata(order_type);
+         }
+      }
+      public AlgoEditingPermissions editing_permissions => _value?.editing_permissions ?? AlgoEditingPermissions.None;
+      public bool can_expand => _algo_root?.can_expand ?? false;
+      public bool is_expanded {
+         get => _value.algo_root?.is_expanded ?? false;
+         set {
+            if (_value != null)
+               _value.is_expanded = value;
+         }
+      }
+      public string display_name => _value?.name ?? string.Empty;
+      public CustomOrderDefinitionImmutable definition => _algo_root?.definition ?? new CustomOrderDefinitionImmutable(new CustomOrderDefinition());
+      public ObservableCollection<IAlgoSelector> child_algo_selectors => _child_algo_selectors;
+      public dynamic children_vm => _algo_root?.children_vm;
+
+      IAlgoVM _algo_root => _value?.algo_root;
+
+      public void assign_to(CustomOrderDefinition value) => _algo_root?.assign_to(value);
+      public bool key_match(KeyEventArgs e) => _algo_root?.key_match(e) ?? false;
+      public void load_from(CustomOrderDefinitionImmutable value) => _algo_root?.load_from(value);
+      public Task<CustomOrderDefinitionImmutable?> load_from_async(CustomOrderDefinitionImmutable definition) => _algo_root is IAlgoVM vm ? vm.load_from_async(definition) : Task.FromResult<CustomOrderDefinitionImmutable?>(null);
+
+      IDisposable _set_hooks(AlgoDefinitionVM vm) {
+         var algo_root_subs = new DisposableContainer();
+         vm.PropertyChanged += on_value_prop_changed;
+         return new CompositeDisposable(
+            vm.observe_algo_root().Subscribe(r => {
+               algo_root_subs.replace(null);
+               _child_algo_selectors.clear_collections();
+               if (r != null) {
+                  if (_data_cache.HasValue) {
+                     _data_cache.Value.forward_to(r);
+                  }
+                  _child_algo_selectors.add_collection(r.child_algo_selectors);
+                  ((INotifyPropertyChanged)r).PropertyChanged += on_algo_root_prop_changed;
+                  algo_root_subs.replace(new CompositeDisposable(
+                     r.subscribe_definition().Subscribe(_ => _definition_changed?.Invoke())) {
+                     () => ((INotifyPropertyChanged)r).PropertyChanged -= on_algo_root_prop_changed
+                  });
+               }
+            }),
+            algo_root_subs) {
+            () => vm.PropertyChanged -= on_value_prop_changed
+         };
+         void on_algo_root_prop_changed(object sender, PropertyChangedEventArgs e) {
+            if (_algo_root_echo_props.Contains(e.PropertyName))
+               RaisePropertyChanged(e.PropertyName);
+         }
+         void on_value_prop_changed(object sender, PropertyChangedEventArgs e) {
+            if (_value_echo_props.Contains(e.PropertyName))
+               RaisePropertyChanged(e.PropertyName);
+         }
+      }
+
+      // permissions
+      void IObserver<AlgoEditingPermissions>.OnNext(AlgoEditingPermissions value) {
+         _data_cache = _data_cache?.with(value) ?? new _ObservedData(value, default, default, default);
+         (_algo_root as IObserver<AlgoEditingPermissions>)?.OnNext(value);
+      }
+      void IObserver<AlgoEditingPermissions>.OnError(Exception error) { }
+      void IObserver<AlgoEditingPermissions>.OnCompleted() { }
+      // model
+      void IObserver<OrdersModel>.OnNext(OrdersModel value) {
+         _data_cache = _data_cache?.with(value) ?? new _ObservedData(default, value, default, default);
+         (_algo_root as IObserver<OrdersModel>)?.OnNext(value);
+      }
+      void IObserver<OrdersModel>.OnError(Exception error) { }
+      void IObserver<OrdersModel>.OnCompleted() { }
+      // security
+      void IObserver<SecurityImmutable?>.OnNext(SecurityImmutable? value) {
+         _data_cache = _data_cache?.with(value) ?? new _ObservedData(default, default, value, default);
+         (_algo_root as IObserver<SecurityImmutable?>)?.OnNext(value);
+      }
+      void IObserver<SecurityImmutable?>.OnError(Exception error) { }
+      void IObserver<SecurityImmutable?>.OnCompleted() { }
+      // security md
+      void IObserver<SecurityMD?>.OnNext(SecurityMD? value) {
+         _data_cache = _data_cache?.with(value) ?? new _ObservedData(default, default, default, value);
+         (_algo_root as IObserver<SecurityMD?>)?.OnNext(value);
+      }
+      void IObserver<SecurityMD?>.OnError(Exception error) { }
+      void IObserver<SecurityMD?>.OnCompleted() { }
+
+      struct _ObservedData {
+         public readonly AlgoEditingPermissions permissions;
+         public readonly OrdersModel model;
+         public readonly SecurityImmutable? security;
+         public readonly SecurityMD? security_md;
+
+         public _ObservedData(AlgoEditingPermissions permissions, OrdersModel model, SecurityImmutable? security, SecurityMD? security_md) {
+            this.permissions = permissions;
+            this.model = model;
+            this.security = security;
+            this.security_md = security_md;
+         }
+
+         public void forward_to(IAlgoVM recipient) {
+            (recipient as IObserver<AlgoEditingPermissions>)?.OnNext(permissions);
+            if (model != null)
+               (recipient as IObserver<OrdersModel>)?.OnNext(model);
+            if (security_md.HasValue)
+               (recipient as IObserver<SecurityMD?>)?.OnNext(security_md);
+            if (security.HasValue)
+               (recipient as IObserver<SecurityImmutable?>)?.OnNext(security);
+         }
+
+         public _ObservedData with(AlgoEditingPermissions? permissions) =>
+            new _ObservedData(permissions ?? this.permissions, model, security, security_md);
+
+         public _ObservedData with(OrdersModel model) =>
+            new _ObservedData(permissions, model, security, security_md);
+
+         public _ObservedData with(SecurityImmutable? security) =>
+            new _ObservedData(permissions, model, security, security_md);
+
+         public _ObservedData with(SecurityMD? security_md) =>
+            new _ObservedData(permissions, model, security, security_md);
+      }
+   }
+}
@@ -0,0 +1,119 @@
+<UserControl
+  x:Class="mbts.ui.spark.AlgoEditorView"
+  x:ClassModifier="internal"
+  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+  xmlns:sp="clr-namespace:mbts.spark"
+  xmlns:u="clr-namespace:mbts.ui"
+  xmlns:cv="clr-namespace:mbts.ui.converters"
+  xmlns:usp="clr-namespace:mbts.ui.spark"
+  xmlns:uag="clr-namespace:mbts.ui.spark.algo"
+  xmlns:uspcv="clr-namespace:mbts.ui.spark.converters"
+  xmlns:sys="clr-namespace:System;assembly=mscorlib"
+>
+  <UserControl.Resources>
+    <ResourceDictionary>
+      <ResourceDictionary.MergedDictionaries>
+        <ResourceDictionary Source="/view/Controls/Order/AlgoPickerNodeView.xaml"/>
+        <ResourceDictionary Source="/view/Controls/Order/AlgoContentTemplateSelector.xaml"/>
+      </ResourceDictionary.MergedDictionaries>
+      <!--Primitive Constants-->
+      <sys:Double x:Key="HorizontalPush1">4</sys:Double>
+      <sys:Double x:Key="HorizontalPush2">8</sys:Double>
+      <sys:Double x:Key="HorizontalPush3">12</sys:Double>
+      <sys:Double x:Key="VerticalPush1">4</sys:Double>
+      <sys:Double x:Key="VerticalPush2">8</sys:Double>
+      <sys:Double x:Key="VerticalPush3">12</sys:Double>
+      <Thickness x:Key="Margin.LP1" Left="{StaticResource HorizontalPush1}"/>
+      <Thickness x:Key="Margin.LP2" Left="{StaticResource HorizontalPush2}"/>
+      <Thickness x:Key="Margin.LP3" Left="{StaticResource HorizontalPush3}"/>
+      <Thickness x:Key="Margin.TP1" Top="{StaticResource VerticalPush1}"/>
+      <Thickness x:Key="Margin.TP2" Top="{StaticResource VerticalPush2}"/>
+      <!--Converters-->
+      <uspcv:OrderTypeBrushConverter x:Key="OrderTypeBrushConverter" DefaultBrush="Transparent"/>
+      <!--Default Styles-->
+      <Style x:Key="ContentHostGroupBoxStyle" TargetType="GroupBox">
+        <Setter Property="Padding" Value="8"/>
+      </Style>
+      <Style TargetType="TextBox">
+        <Setter Property="u:TextBoxBehavior.EnterKeyBehavior" Value="CommitAndRelease"/>
+        <Setter Property="u:TextBoxBehavior.ReleaseOnEscape" Value="True"/>
+      </Style>
+
+      <Style TargetType="uag:AlgoPickerNodeView" BasedOn="{StaticResource {x:Type uag:AlgoPickerNodeView}}">
+        <Setter Property="DropDownStyleKey" Value="{Binding DataContext, RelativeSource={RelativeSource AncestorType=usp:AlgoEditorView}, Converter={x:Static usp:AlgoContentTemplateSelector.AlgoDropDownStyleKeyConverter}}"/>
+      </Style>
+    </ResourceDictionary>
+  </UserControl.Resources>
+  <GroupBox
+    x:Name="content_host"
+    Grid.Row="2"
+    Background="Transparent"
+    BorderBrush="{Binding algo_root, Converter={StaticResource OrderTypeBrushConverter}}"
+    Margin="0,6,0,0"
+    Padding="12,8"
+  >
+    <GroupBox.Style>
+      <Style TargetType="GroupBox" BasedOn="{StaticResource ContentHostGroupBoxStyle}">
+        <Setter Property="BorderThickness" Value="1"/>
+        <Setter Property="BorderBrush" Value="Transparent"/>
+        <Style.Triggers>
+          <Trigger Property="BorderBrush" Value="Transparent">
+            <Setter Property="BorderThickness" Value="0"/>
+          </Trigger>
+          <Trigger Property="usp:AlgoEditorView.IsMouseOverNodeContent" Value="True">
+            <Setter Property="BorderThickness" Value="2"/>
+          </Trigger>
+        </Style.Triggers>
+      </Style>
+    </GroupBox.Style>
+    <GroupBox.Header>
+      <ComboBox
+        ToolTipService.ShowOnDisabled="True"
+        Width="140"
+        Margin="{StaticResource Margin.LP1}"
+        ItemsSource="{Binding algos_view}"
+        SelectedItem="{Binding algo_root}"
+      >
+        <ComboBox.Style>
+          <Style TargetType="ComboBox">
+            <Style.Triggers>
+              <DataTrigger Binding="{Binding templates.Count, Converter={StaticResource IntIsZeroConverter}, FallbackValue={u:False}}" Value="{u:True}">
+                <Setter Property="IsEnabled" Value="True"/>
+              </DataTrigger>
+              <DataTrigger Binding="{Binding templates.Count, Converter={StaticResource IntIsZeroConverter}, FallbackValue={u:False}}" Value="{u:False}">
+                <Setter Property="IsEnabled" Value="False"/>
+                <Setter Property="ToolTip" Value="Cannot change structure while templates are present."/>
+              </DataTrigger>
+            </Style.Triggers>
+          </Style>
+        </ComboBox.Style>
+        <ComboBox.IsEnabled>
+          <Binding Path="editing_permissions">
+            <Binding.Converter>
+              <cv:EnumHasFlagsConverter>
+                <sp:AlgoEditingPermissions>AllowEditStructure</sp:AlgoEditingPermissions>
+              </cv:EnumHasFlagsConverter>
+            </Binding.Converter>
+          </Binding>
+        </ComboBox.IsEnabled>
+        <ComboBox.ItemTemplate>
+          <DataTemplate>
+            <usp:OrderTypeItem DisplayName="{Binding display_name}" BadgeFill="{Binding meta.Color, Converter={StaticResource ColorToBrushConverter}}"/>
+          </DataTemplate>
+        </ComboBox.ItemTemplate>
+      </ComboBox>
+    </GroupBox.Header>
+    <ContentControl
+      Grid.IsSharedSizeScope="True"
+      Content="{Binding algo_root, Converter={x:Static usp:AlgoContentTemplateSelector.DataContextConverter}}"
+      ContentTemplateSelector="{StaticResource AlgoTemplateSelector}"
+      Margin="{StaticResource Margin.TP1}"
+      Visibility="{Binding algo_root.can_expand, Converter={StaticResource BooleanToVisibilityConverter}}"
+    >
+      <ContentControl.Resources>
+        <Style TargetType="GroupBox" BasedOn="{StaticResource ContentHostGroupBoxStyle}"/>
+      </ContentControl.Resources>
+    </ContentControl>
+  </GroupBox>
+</UserControl>
@@ -0,0 +1,28 @@
+using mbts.ui.extensions;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Input;
+
+namespace mbts.ui.spark {
+   partial class AlgoEditorView : UserControl {
+      public AlgoEditorView() {
+         InitializeComponent();
+         content_host.PreviewMouseMove += content_host_PreviewMouseMove;
+         content_host.MouseEnter += content_host_MouseEnter;
+         content_host.MouseLeave += content_host_MouseLeave;
+         // local methods
+         void content_host_PreviewMouseMove(object sender, MouseEventArgs e) => refresh_is_mouse_over_content_host(e);
+         void content_host_MouseEnter(object sender, MouseEventArgs e) => refresh_is_mouse_over_content_host(e);
+         void content_host_MouseLeave(object sender, MouseEventArgs e) => refresh_is_mouse_over_content_host(e);
+         void refresh_is_mouse_over_content_host(MouseEventArgs e) => content_host.set_current_if_changed(IsMouseOverNodeContentProperty, this.ChildAtPoint<GroupBox>(e.GetPosition(this)) == content_host);
+      }
+
+      #region IsMouseOverNodeContent 
+      public static readonly DependencyProperty IsMouseOverNodeContentProperty =
+         DependencyProperty.RegisterAttached("IsMouseOverNodeContent", typeof(bool), typeof(AlgoEditorView), new PropertyMetadata(false));
+
+      public static bool GetIsMouseOverNodeContent(DependencyObject d) => (bool)d.GetValue(IsMouseOverNodeContentProperty);
+      public static void SetIsMouseOverNodeContent(DependencyObject d, bool value) => d.SetValue(IsMouseOverNodeContentProperty, value);
+      #endregion
+   }
+}
@@ -14,10 +14,13 @@ using mbts.ui.shell;
 using mbts.ui.utility;
 using mbts.utils;
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
+using System.Collections.Specialized;
 using System.ComponentModel;
 using System.Linq;
+using System.Reactive.Disposables;
 using System.Reactive.Linq;
 using System.Reactive.Subjects;
 using System.Windows.Data;
@@ -42,7 +45,7 @@ namespace mbts.spark {
      public FillsVM(IBus bus, OrdersModel model, IObservable<StartupData> state_obs, IWindowSettingsManager<GridSettings> settings_manager)
         : this(bus, model, state_obs, _get_observable(bus, model, state_obs), settings_manager) { }

-      FillsVM(IBus bus, OrdersModel model, IObservable<StartupData> state_obs, IConnectableObservable<TableUpdate<FillTuple, string>> fills_source, IWindowSettingsManager<GridSettings> settings_manager) {
+      public FillsVM(IBus bus, OrdersModel model, IObservable<StartupData> state_obs, IObservable<TableUpdate<FillTuple, string>> fills_source, IWindowSettingsManager<GridSettings> settings_manager) {
         _model = model;
         _settings_manager = settings_manager;
         /// Columns
@@ -98,16 +101,17 @@ namespace mbts.spark {
         // grid settings
         grid_settings_manager = new SimpleGridSettingsManager<Row>(columns, new Dictionary<string, GridColumnSettingsFeatureFlags> { }, rows);
         // this will initialize the immutable properties that correspond to the col_settings_flags above (e.g. Bid/Ask font_color_override, etc.)
-         grid_settings_manager.load_from(settings_manager.current_settings());
+         if (_settings_manager != null)
+            grid_settings_manager.load_from(_settings_manager.current_settings());
         //
-         _dispose = Disposable.Create(
+         _dispose = new CompositeDisposable(
            ObservableAutoWrapper.connect(col_tups, columns, ct => ct.col),
            fills_source.OnDispatcher().Subscribe(t => {
               _rows.update(t);
               Set(ref _total_row_count, t.state.Count, nameof(total_row_count));
            }),
            state_obs.OnDispatcher().Subscribe(s => {
-               if (s.grid != null) {
+               if (s.grid != null && _settings_manager != null) {
                  // this means we are not using defaults,
                  // Note: settings_manager in turn notifies grid_settings_manager of this update
                  _settings_manager.instance_settings = s.grid;
@@ -120,8 +124,8 @@ namespace mbts.spark {
               };
               rows_manager.on_settings(fs, s.sorting_criterion);
            }),
-            settings_manager.subscribe_current().OnDispatcher().Subscribe(grid_settings_manager),
-            fills_source.Connect()
+            settings_manager == null ? Disposable.empty : settings_manager.subscribe_current().OnDispatcher().Subscribe(grid_settings_manager),
+            (fills_source as IConnectableObservable<TableUpdate<FillTuple, string>>)?.Connect() ?? Disposable.empty
         );
         // local methods
         void add_col<TFilter>(Columns col_key, string header, Func<Row, string> get_text, IDataGridColumnPersistentFilter<FillTuple, TFilter> filter, string filter_template, double width) =>
@@ -153,12 +157,12 @@ namespace mbts.spark {
      public IEnumerable<SortingCriteria> get_sorting_criterion() =>
         _sort_manager.create();

+      public void on_sorting(object sender, DIYGridSortingEventArgs e) =>
+         _sort_manager.on_sorting(e);
+
      static Columns _col_key(ColumnBase column) =>
         ((IKeyedColumn<Columns>)column).key;

-      void IHandleGridSorting.on_sorting(object sender, DIYGridSortingEventArgs e) =>
-         _sort_manager.on_sorting(e);
-
      public FilterStates get_filters() =>
         _filters_manager.create();

@@ -0,0 +1,49 @@
+using mbts.ui;
+using mbts.ui.controls;
+using System;
+
+namespace mbts.spark {
+   /// <summary>
+   /// This class provides a stable DataContext for a fills view, with an internal <see cref="FillsVM"/> that may be disposed and recreated as needed.
+   /// </summary>
+   class FillsVMContainer : IHandleGridSorting, IDisposable, IWillLetYouKnowWhenIDispose {
+      bool _disposed;
+      FillsVM _value;
+
+      public event Action<bool> OnDisposed;
+
+      public FillsVM value {
+         get => _value;
+         set {
+            if (value != _value) {
+               if (_disposed)
+                  throw new ObjectDisposedException(nameof(FillsVMContainer));
+               Disposable.replace(ref _value, value);
+               if (_value != null) {
+                  rows.add_collection(_value.rows);
+                  columns.add_collection(_value.columns);
+               } else {
+                  rows.clear_collections();
+                  columns.clear_collections();
+               }
+            }
+         }
+      }
+
+      public ObservableAggregateCollection<FillsVM.Row> rows { get; } = new ObservableAggregateCollection<FillsVM.Row>();
+      public ObservableAggregateCollection<DIYGrid.ColumnBase> columns { get; } = new ObservableAggregateCollection<DIYGrid.ColumnBase>();
+
+      public void Dispose() {
+         if (_disposed)
+            throw new ObjectDisposedException(nameof(FillsVMContainer));
+         value = null;
+         OnDisposed?.Invoke(true);
+         _disposed = true;
+      }
+
+      public void on_sorting(object sender, DIYGridSortingEventArgs e) {
+         if (!_disposed)
+            _value?.on_sorting(sender, e);
+      }
+   }
+}
@@ -18,7 +18,6 @@ using StartupData = bts.shell.FillsWindowFactory.StartupData;
 namespace mbts.spark {
   class FillsWindow : SparkWindow<StartupData>, ISharedWindow {
      public const string window_type_name = "Fills";
-      const string _thread_id = "Fills";
      readonly AllowOnce _init_guard = new AllowOnce("Fills");
      readonly OrdersModel _orders_model;
      readonly IWindowSettingsManager<GridSettings> _settings_manager;
@@ -33,6 +32,7 @@ namespace mbts.spark {
         _orders_model = orders_model;
         _state = state;
         _settings_manager = settings_manager;
+         thread_id = config.Configuration.get<bts.config.MultiThreadedWindows>().fills ? "Fills" : null;
      }

      event Action<FillsWindowFactory.StartupData> _state_changed;
@@ -48,7 +48,7 @@ namespace mbts.spark {
         + LAUNCHER_BUTTON_BORDER_WIDTH
         + EXTRA_FOR_NO_HORIZONTAL_SCROLLBAR_WIDTH;

-      public string thread_id => _thread_id;
+      public string thread_id { get; }

      public void thread_init() {
         _init_guard.check_access();
@@ -33,7 +33,7 @@ namespace bts.shell {
         _settings_hub = settings_hub;
         _orders_model = orders_model;
         _md_auxiliary_model = md_auxiliary_model;
-         _ladder_conf = new LadderConfig(Configuration.get<bts.config.LadderKnobs>(), Configuration.get<bts.config.toggles.LaddersOnThreads>().enabled);
+         _ladder_conf = new LadderConfig(Configuration.get<bts.config.LadderKnobs>(), Configuration.get<bts.config.MultiThreadedWindows>().ladder);
         _dispose = Disposable.Create(
            bus.subscribe(SparkTags.SecuritiesTag).Subscribe(s => _securities = s),
            bus.subscribe(SparkTags.ShowLadderTag).OnDispatcher().Subscribe(s => show_windows(new[] { s })),
@@ -95,7 +95,7 @@
            <PathGeometry x:Key="TreeArrow" Figures="M0,0 L0,6 L6,0 z"/>
            <SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Fill" Color="#FFFFFFFF"/>
            <SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Stroke" Color="#FF818181"/>
-            <Style x:Key="{x:Static sp:OrderBookView.ExpandCollapseToggleStyleKey}" TargetType="{x:Type ToggleButton}">
+            <Style x:Key="{x:Static sp:OrderBookGridView.ExpandCollapseToggleStyleKey}" TargetType="{x:Type ToggleButton}">
              <Setter Property="Focusable" Value="False"/>
              <Setter Property="Width" Value="16"/>
              <Setter Property="Height" Value="16"/>
@@ -20,7 +20,7 @@ namespace mbts.spark {
      }
   }

-   class MiniOrderBookRowView : DIYGrid.HighPerformanceRow<OrderBookRowVM, OrderBookView.Columns> {
+   class MiniOrderBookRowView : DIYGrid.HighPerformanceRow<OrderBookRowVM, OrderBookGridView.ColumnKeys> {
      public MiniOrderBookRowView() : base() { }
   }
 }
@@ -21,14 +21,13 @@ using System.Windows.Controls.Primitives;
 using System.Windows.Data;
 using System.Windows.Media;
 using static bts.shell.OrderBookWindowFactory;
-using static mbts.spark.OrderBookView;
+using Columns = mbts.spark.OrderBookGridView.ColumnKeys;
 using static mbts.ui.controls.DIYGrid;
 using OrderType = bts.api.orderman.CustomOrderDefinition.CustomOneofCase;

 namespace mbts.spark {
   // This interface is used to hide ColumnBase.SortDirection, and offer a SortDirection member that does NOT require a DependencyProperty lookup.
   interface ICVOrderBookColumn : IKeyedColumn<Columns>, IGridColumn {
-      string sort_member_path { get; }
      ListSortDirection? SortDirection { get; set; }
      IDataGridColumnFilter<OrderSecurityAlgoMeta> filter { get; }
      IComparer<OrderBookRowVM> comparer { get; }
@@ -78,7 +77,6 @@ namespace mbts.spark {
            Add(symbol_column = new SimpleTextColumn<string[]>(
               Columns.Symbol,
               DefaultColumnHeaders.Symbol,
-               nameof(OrderBookRowVM.symbol),
               r => r.symbol,
               DefaultColumnWidths.Symbol,
               DiscreteValuesFilterVM.Create<OrderSecurityAlgoMeta, string>(
@@ -92,7 +90,6 @@ namespace mbts.spark {
            Add(time_created_column = new SimpleTextColumn<TimeFilterTuple>(
               Columns.Time,
               "Time",
-               nameof(OrderBookRowVM.time_created),
               r => r.time_created_text,
               DefaultColumnWidths.Time,
               new TimeFilterVM<OrderSecurityAlgoMeta>(
@@ -104,7 +101,6 @@ namespace mbts.spark {
            Add(last_change_column = new SimpleTextColumn<TimeFilterTuple>(
               Columns.LastChange,
               "Last Change",
-               nameof(OrderBookRowVM.last_change),
               r => r.last_change_text,
               DefaultColumnWidths.Time,
               new TimeFilterVM<OrderSecurityAlgoMeta>(
@@ -116,7 +112,6 @@ namespace mbts.spark {
            Add(user_column = new SimpleTextColumn<string[]>(
               Columns.User,
               DefaultColumnHeaders.User,
-               nameof(OrderBookRowVM.user),
               r => r.user,
               DefaultColumnWidths.User,
               DiscreteValuesFilterVM.Create<OrderSecurityAlgoMeta, string>(
@@ -129,7 +124,6 @@ namespace mbts.spark {
            Add(account_column = new SimpleTextColumn<string[]>(
               Columns.Account,
               DefaultColumnHeaders.Account,
-               nameof(OrderBookRowVM.account),
               r => r.account,
               DefaultColumnWidths.Account,
               DiscreteValuesFilterVM.Create<OrderSecurityAlgoMeta, string, string[]>(
@@ -144,7 +138,6 @@ namespace mbts.spark {
            Add(exchange_column = new SimpleTextColumn<Venue[]>(
               Columns.Exchange,
               DefaultColumnHeaders.Exchange,
-               nameof(OrderBookRowVM.exchange),
               r => r.exchange.ToString(),
               DefaultColumnWidths.Exchange,
               DiscreteValuesFilterVM.Create<OrderSecurityAlgoMeta, Venue>(
@@ -157,7 +150,6 @@ namespace mbts.spark {
            Add(time_in_force_column = new SimpleTextColumn<TimeInForce[]>(
               Columns.TimeInForce,
               DefaultColumnHeaders.TimeInForce,
-               nameof(OrderBookRowVM.time_in_force),
               r => r.time_in_force.ToString(),
               DefaultColumnWidths.TimeInForce,
               DiscreteValuesFilterVM.Create<OrderSecurityAlgoMeta, TimeInForce>(
@@ -176,14 +168,13 @@ namespace mbts.spark {
            Add(sub_type_column = new SimpleTextColumn<OrderSubType[]>(
               Columns.SubType,
               "Sub Type",
-               nameof(OrderBookRowVM.order_sub_type),
               r => r.order_sub_type_text,
               80,
               DiscreteValuesFilterVM.Create<OrderSecurityAlgoMeta, OrderSubType>(
                  EnumHelper.get_values<OrderSubType>().ToList(),
                  ort => ort.order.sub_type(),
                  nameof(OrderBookRowVM.order_sub_type)),
-               SubTypeFilterTemplateKey,
+               OrderBookGridView.SubTypeFilterTemplateKey,
               _wrap_comparer(r => r.order_sub_type)));
            // side
            Add(side_column = new SideColumn(
@@ -205,7 +196,6 @@ namespace mbts.spark {
            Add(price_column = new SimpleTextColumn<DoubleMinMaxState>(
               Columns.Price,
               "Price",
-               nameof(OrderBookRowVM.price),
               r => r.price_text,
               DefaultColumnWidths.Price,
               new DoubleMinMax<OrderSecurityAlgoMeta>(
@@ -221,7 +211,6 @@ namespace mbts.spark {
            Add(avg_price_column = new SimpleTextColumn<DoubleMinMaxState>(
               Columns.AvgFilled,
               "Avg Price",
-               nameof(OrderBookRowVM.avg_price),
               r => r.avg_price_text,
               DefaultColumnWidths.Price,
               new DoubleMinMax<OrderSecurityAlgoMeta>(
@@ -233,7 +222,6 @@ namespace mbts.spark {
            Add(last_price_column = new SimpleTextColumn<DoubleMinMaxState>(
               Columns.LastPrice,
               "Last Filled",
-               nameof(OrderBookRowVM.last_price),
               r => r.last_price_text,
               DefaultColumnWidths.Price,
               new DoubleMinMax<OrderSecurityAlgoMeta>(
@@ -245,7 +233,6 @@ namespace mbts.spark {
            Add(status_column = new SimpleTextColumn<OrderStatus[]>(
               Columns.Status,
               "Status",
-               nameof(OrderBookRowVM.status),
               r => r.status.ToString(),
               80,
               DiscreteValuesFilterVM.Create<OrderSecurityAlgoMeta, OrderStatus>(
@@ -263,7 +250,6 @@ namespace mbts.spark {
            Add(security_key_column = new SimpleTextColumn<string>(
               Columns.SecurityKey,
               DefaultColumnHeaders.SecurityKey,
-               nameof(OrderBookRowVM.security_key),
               r => r.security_key.ToString(),
               DefaultColumnWidths.SecurityKey,
               new RegexFilterVM<OrderSecurityAlgoMeta>(
@@ -275,7 +261,6 @@ namespace mbts.spark {
            Add(order_key_column = new SimpleTextColumn<string>(
               Columns.OrderKey,
               DefaultColumnHeaders.OrderKey,
-               nameof(OrderBookRowVM.order_key),
               r => r.order_key.ToString(),
               DefaultColumnWidths.OrderKey,
               new RegexFilterVM<OrderSecurityAlgoMeta>(
@@ -287,7 +272,6 @@ namespace mbts.spark {
            Add(parent_key_column = new SimpleTextColumn<string>(
               Columns.ParentKey,
               "Parent Key",
-               nameof(OrderBookRowVM.parent_order_key),
               r => r.parent_order_key.ToString(),
               DefaultColumnWidths.ParentKey,
               new RegexFilterVM<OrderSecurityAlgoMeta>(
@@ -295,6 +279,17 @@ namespace mbts.spark {
                  nameof(OrderBookRowVM.parent_order_key)),
               DataGridFilterKnownTemplates.Regex,
               _wrap_comparer(r => r.parent_order_key)));
+            // attached target order key
+            Add(attached_target_order_key_column = new SimpleTextColumn<string>(
+               Columns.AttachedTargetOrderKey,
+               DefaultColumnHeaders.AttachedTargetOrderKey,
+               r => r.order.attached_target_order_key().ToString(),
+               DefaultColumnWidths.AttachedTargetOrderKey,
+               new RegexFilterVM<OrderSecurityAlgoMeta>(
+                  ort => ort.order.attached_target_order_key().ToString(),
+                  nameof(OrderBookRowVM.parent_order_key)),
+               DataGridFilterKnownTemplates.Regex,
+               _wrap_comparer(r => r.order.attached_target_order_key())));
         }

         public event Action filter_changed;
@@ -323,10 +318,13 @@ namespace mbts.spark {
         public SimpleTextColumn<string> security_key_column { get; }
         public SimpleTextColumn<string> order_key_column { get; }
         public SimpleTextColumn<string> parent_key_column { get; }
+         public SimpleTextColumn<string> attached_target_order_key_column { get; }

         public (FilterStates filters, IReadOnlyList<SortingCriteria> sorting) create() => (
            new FilterStates {
               order_key_regex = order_key_column.filter.get_state(),
+               parent_key_regex = parent_key_column.filter.get_state(),
+               attached_target_order_key_regex = attached_target_order_key_column.filter.get_state(),
               time_created = time_created_column.filter.get_state(),
               users = user_column.filter.get_state(),
               accounts = account_column.filter.get_state(),
@@ -364,6 +362,8 @@ namespace mbts.spark {
               time_in_force_column.filter.load_state(fs.tifs);
               exchange_column.filter.load_state(fs.exchanges);
               order_key_column.filter.load_state(fs.order_key_regex);
+               parent_key_column.filter.load_state(fs.parent_key_regex);
+               attached_target_order_key_column.filter.load_state(fs.attached_target_order_key_regex);
               avg_price_column.filter.load_state(fs.avg_price);
               last_price_column.filter.load_state(fs.last_price);
               status_column.filter.load_state(fs.statuses);
@@ -480,13 +480,12 @@ namespace mbts.spark {
         protected readonly Func<OrderBookRowVM, string> _get_text;
         GlyphContext _root_glyph_context, _child_glyph_context;

-         protected OrderbookColumnBase(Columns col_key, string header, Func<OrderBookRowVM, string> get_text, string sort_prop, double width,
+         protected OrderbookColumnBase(Columns col_key, string header, Func<OrderBookRowVM, string> get_text, double width,
            IDataGridColumnPersistentFilter<OrderSecurityAlgoMeta, T> filter, string filter_template, IComparer<OrderBookRowVM> comparer) : base(col_key) {
            id = key.ToString();
            Width = width;
            Header = header;
            _get_text = get_text;
-            sort_member_path = sort_prop;
            this.filter = filter;
            _filter_template = filter_template;
            _cached_sort_direction = SortDirection;
@@ -515,9 +514,9 @@ namespace mbts.spark {
      }

      public class SimpleTextColumn<TFilterState> : OrderbookColumnBase<TFilterState>, IRenderColumn<OrderBookRowVM> {
-         public SimpleTextColumn(Columns key, string header, string sort_prop, Func<OrderBookRowVM, string> get_text, double width,
+         public SimpleTextColumn(Columns key, string header, Func<OrderBookRowVM, string> get_text, double width,
            IDataGridColumnPersistentFilter<OrderSecurityAlgoMeta, TFilterState> filter, string filter_template, IComparer<OrderBookRowVM> comparer)
-            : base(key, header, get_text, sort_prop, width, filter, filter_template, comparer) { }
+            : base(key, header, get_text, width, filter, filter_template, comparer) { }

         public void draw(OrderBookRowVM row, DrawingContext dc, ColumnGeometry position, double row_height) =>
            CellRender.draw_text(dc, _get_glyph_context(row), font_size, _get_text(row), position, row_height,
@@ -527,7 +526,7 @@ namespace mbts.spark {
      #region Explicit Column Defs
      public class SideColumn : OrderbookColumnBase<Side[]>, IRenderColumn<OrderBookRowVM> {
         public SideColumn(IDataGridColumnPersistentFilter<OrderSecurityAlgoMeta, Side[]> filter)
-            : base(Columns.Side, "B/S", r => r.side.ToString(), nameof(OrderBookRowVM.side), DefaultColumnWidths.Side, filter, DataGridFilterKnownTemplates.EnumValues, _wrap_comparer(r => r.side)) { }
+            : base(Columns.Side, "B/S", r => r.side.ToString(), DefaultColumnWidths.Side, filter, DataGridFilterKnownTemplates.EnumValues, _wrap_comparer(r => r.side)) { }

         public void draw(OrderBookRowVM row, DrawingContext dc, ColumnGeometry position, double row_height) =>
            CellRender.draw_text(dc, _get_glyph_context(row), font_size, row.side.ToString(), position, row_height,
@@ -536,9 +535,7 @@ namespace mbts.spark {

      public class SizeColumn : OrderbookColumnBase<UIntMinMaxState>, IRenderColumn<OrderBookRowVM> {
         public SizeColumn(IDataGridColumnPersistentFilter<OrderSecurityAlgoMeta, UIntMinMaxState> filter)
-            : base(Columns.Size, "Qty", r => r.quantity.ToString(), nameof(OrderBookRowVM.quantity), DefaultColumnWidths.Size, filter, DataGridFilterKnownTemplates.UIntMinMax, _wrap_comparer(r => r.quantity)) {
-            sort_member_path = nameof(OrderBookRowVM.quantity);
-         }
+            : base(Columns.Size, "Qty", r => r.quantity.ToString(), DefaultColumnWidths.Size, filter, DataGridFilterKnownTemplates.UIntMinMax, _wrap_comparer(r => r.quantity)) { }

         public void draw(OrderBookRowVM row, DrawingContext dc, ColumnGeometry position, double row_height) =>
            CellRender.draw_text(dc, _get_glyph_context(row), font_size, row.quantity.ToString(), position, row_height,
@@ -547,9 +544,7 @@ namespace mbts.spark {

      public class FilledColumn : OrderbookColumnBase<UIntMinMaxState>, IRenderColumn<OrderBookRowVM> {
         public FilledColumn(IDataGridColumnPersistentFilter<OrderSecurityAlgoMeta, UIntMinMaxState> filter)
-            : base(Columns.Filled, "Filled Qty", r => r.filled_quantity.ToString(), nameof(OrderBookRowVM.filled_quantity), DefaultColumnWidths.Size, filter, DataGridFilterKnownTemplates.UIntMinMax, _wrap_comparer(r => r.filled_quantity)) {
-            sort_member_path = nameof(OrderBookRowVM.filled_quantity);
-         }
+            : base(Columns.Filled, "Filled Qty", r => r.filled_quantity.ToString(), DefaultColumnWidths.Size, filter, DataGridFilterKnownTemplates.UIntMinMax, _wrap_comparer(r => r.filled_quantity)) { }

         public void draw(OrderBookRowVM row, DrawingContext dc, ColumnGeometry position, double row_height) =>
            CellRender.draw_text(dc, _get_glyph_context(row), font_size, row.filled_quantity.ToString(), position, row_height,
@@ -562,7 +557,6 @@ namespace mbts.spark {
            : base(Columns.OrderType, new Binding(nameof(OrderBookRowVM.badge_fill)), new Binding(nameof(OrderBookRowVM.display_name)), filter) {
            id = key.ToString();
            this.filter = filter;
-            sort_member_path = nameof(OrderBookRowVM.order_type);
            font_weight_binding = RenderUtils.get_font_weight_binding();
            _cached_sort_direction = SortDirection;
         }
@@ -587,8 +581,7 @@ namespace mbts.spark {
            id = key.ToString();
            this.filter = filter;
            Header = "Last Message";
-            Width = DIYGrid.DefaultColumnWidths.LastMessage;
-            sort_member_path = nameof(OrderBookRowVM.last_msg);
+            Width = DefaultColumnWidths.LastMessage;
            tooltip_binding = new Binding(nameof(OrderBookRowVM.last_msg));
         }

@@ -616,7 +609,6 @@ namespace mbts.spark {
            this.filter = filter;
            Header = DefaultColumnHeaders.Security;
            Width = DefaultColumnWidths.Security;
-            sort_member_path = nameof(OrderBookRowVM.security);
            _cached_sort_direction = SortDirection;
         }

@@ -634,7 +626,7 @@ namespace mbts.spark {
            toggle_button.SetBinding(ToggleButton.IsCheckedProperty, new Binding(nameof(OrderBookRowVM.is_expanded)));
            toggle_button.SetBinding(ToggleButton.MarginProperty, new Binding(nameof(OrderBookRowVM.depth_level)) { Converter = _margin_converter });
            toggle_button.SetBinding(ToggleButton.VisibilityProperty, new Binding(nameof(OrderBookRowVM.is_parent)) { Converter = _expander_visiblilty_converter });
-            toggle_button.SetResourceReference(ToggleButton.StyleProperty, ExpandCollapseToggleStyleKey);
+            toggle_button.SetResourceReference(ToggleButton.StyleProperty, OrderBookGridView.ExpandCollapseToggleStyleKey);
            //
            var security_view = new TextBlock { Foreground = font_brush };
            security_view.SetBinding(TextBlock.FontFamilyProperty, new Binding(nameof(font_family)) { Source = this });
@@ -651,6 +643,7 @@ namespace mbts.spark {
            grid.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(1, GridUnitType.Star) });
            grid.Children.Add(toggle_button);
            grid.Children.Add(security_view);
+
            grid.VerticalAlignment = VerticalAlignment.Center;
            //
            var border = new Border { Child = grid };
@@ -6,14 +6,16 @@ using mbts.ui;
 using mbts.ui.controls;
 using mbts.ui.shell;
 using System;
+using System.Reactive;
 using System.Linq;
 using System.Threading.Tasks;
 using System.Windows;
 using System.Windows.Input;
 using System.Windows.Media;
+using System.Reactive.Linq;

 namespace mbts.spark {
-   partial class OrderBookRowVM : DisposableViewModelBase, IEquatable<OrderBookRowVM>, DIYGrid.IRowVM, DIYGrid.IActionableRowVM {
+   partial class OrderBookRowVM : DisposableViewModelBase, IEquatable<OrderBookRowVM>, DIYGrid.IRowVM {
      const string _unknown_security_price_format_string = "0.#########";
      const int _unknown_security_price_num_fractional_digits = 9;
      readonly OrderBookVM _owner;
@@ -44,12 +46,26 @@ namespace mbts.spark {
         modify_order_price?.TryRaiseCanExecuteChanged();
      }

+      //// This takes care of the case where the OB has all rows visible
+      //// and an order is cancelled outside of the OB (say via the ladder).
+      //// Since the OB window Commands only revaluate their CanExecuteChanged
+      //// when the OrderBookVM.selected_order_changes, this emulates the selected
+      //// order changing since the current_row setter invokes the selected_order_changed
+      //// handler
+      public IObservable<OrderSecurityAlgoMeta> subscribe_data() {
+         return Observable.FromEvent<Action, OrderSecurityAlgoMeta>(
+            cb => () => cb(order_tuple), 
+            cb => invalidated += cb, 
+            cb => invalidated -= cb);
+      }
+
      protected override void Dispose(bool disposing) {
         this.invalidated -= OrderBookRowVM_invalidated;
         base.Dispose(disposing);
      }

      public event Action invalidated;
+      public event Action<(OrderSecurityAlgoMeta oldval, OrderSecurityAlgoMeta newval)> updated;

      // Core
      public OrderSecurityAlgoMeta order_tuple { get; private set; }
@@ -127,8 +143,8 @@ namespace mbts.spark {
      public ICommand toggle_command => _toggle_expanded_cmd ?? (
         _toggle_expanded_cmd = new DelegateCommand(() => is_expanded = !is_expanded));

-      ICommand DIYGrid.IActionableRowVM.default_command => _show_order_modify_cmd ??
-         (_show_order_modify_cmd = new DelegateCommand(() => _owner.show_order_modify(this), () => status == OrderStatus.Working));
+      public ICommand show_order_modify_cmd => 
+       _show_order_modify_cmd ?? (_show_order_modify_cmd = new DelegateCommand(() => _owner.show_order_modify(this), () => status == OrderStatus.Working));

      public ICommand cancel_command => _cancel_cmd ??
         (_cancel_cmd = new DelegateCommand(() => _owner.cancel_order(this), () => status == OrderStatus.Working));
@@ -170,10 +186,10 @@ namespace mbts.spark {
      public void update(OrderSecurityAlgoMeta order_tuple) {
         Log.assert(order_tuple.order.Key == this.order.Key, "OrderBookRowVM: update_order was called with an order with the wrong key.");
         bool had_security = _security.HasValue;
-         var old_meta = this.order_tuple.meta;
+         var old_order_tuple = this.order_tuple;
         // _show_order_modify_cmd is lazy (instantiated in the default_command getter); it might be null, don't not force instantiation
         bool? could_modify_execute = _show_order_modify_cmd?.CanExecute(null);
-         OrderRecordImmutable old_order = order;
+         OrderRecordImmutable old_order = old_order_tuple.order;
         this.order_tuple = order_tuple;
         // most cells are "render-cells," which don't use databindings - the only way to update such cells is to raise the invalidated event
         bool invalidate = !(
@@ -200,10 +216,12 @@ namespace mbts.spark {
            // need to raise invalidated to refresh the price cells (the security.ContractSpec determines how they are formatted - Ticks!)
            invalidate = true;
         }
-         if (old_meta?.badge_color != order_tuple.meta?.badge_color) {
+         if (old_order_tuple.meta?.badge_color != order_tuple.meta?.badge_color) {
            _badge_fill = null;
            RaisePropertyChanged(nameof(badge_fill));
         }
+         if (old_order_tuple.display_name() != order_tuple.display_name())
+            RaisePropertyChanged(nameof(display_name));
         if (old_order.status() != order.status()) {
            invalidate = true;
            RaisePropertyChanged(nameof(status));
@@ -213,6 +231,7 @@ namespace mbts.spark {
         }
         if (could_modify_execute.HasValue && could_modify_execute.Value != _show_order_modify_cmd.CanExecute(null))
            _show_order_modify_cmd.RaiseCanExecuteChanged();
+         updated?.Invoke((old_order_tuple, order_tuple));
         if (invalidate)
            raise_invalidated();
      }
@@ -19,12 +19,11 @@ using System.Windows.Controls;
 using System.Windows.Input;
 using static bts.shell.OrderBookWindowFactory;
 using static mbts.spark.OrderBookView;
-using _GridSettingsManager = 
+using _GridSettingsManager =
   mbts.ui.GridSettingsManager<
-      mbts.spark.OrderBookRowVM, 
-      bts.api.orderman.OrderSecurity, 
-      bts.shell.INotificationServiceDataCache, 
-      mbts.OrderRecordTuplePredicate, 
+      mbts.spark.OrderBookRowVM,
+      bts.api.orderman.OrderSecurity,
+      mbts.OrderRecordTuplePredicate,
      bts.shell.OrderBookWindowFactory.OrderBookGridSettings>;

 namespace mbts.spark {
@@ -54,6 +53,7 @@ namespace mbts.spark {
         collapse_all_rows_command = new DelegateCommand(_row_collection.collapse_all);
         expand_all_rows_command = new DelegateCommand(_row_collection.expand_all);
         grid_settings_manager = _create_grid_settings_manager(owner_title, bus, notification_service, model, rows, core_columns);
+
         _resources = new List<IDisposable> {
            model.on_order_tuples.OnDispatcher().Subscribe(_row_collection.update),
            grid_settings_manager,
@@ -62,7 +62,12 @@ namespace mbts.spark {
               _row_collection.CollectionChanged -= _row_collection_CollectionChanged;
               Disposable.dispose(_row_collection);
            }),
-            _columns
+            _columns,
+            _current_row.SubscribeHookLatest(
+               r => r.newval.subscribe_data().Subscribe( 
+                  data => selected_order_changed?.Invoke(data.order)
+               )
+            )
         };
         if (settings_manager != null) {
            _resources.Add(settings_manager.subscribe_current().OnDispatcher().Subscribe(grid_settings_manager));
@@ -231,21 +236,25 @@ namespace mbts.spark {
            col_settings_flags[c.ToString()] = GridColumnSettingsFeatureFlags.ImmutableFontColor | GridColumnSettingsFeatureFlags.ImmutableFontWeight;
         }
         return new _GridSettingsManager(
-            owner_title, bus, notification_service, model, rows, columns,
+            owner_title, bus, model, rows, columns,
+            () => new OrderRecordTuplePredicate(),
            () => {
-               var pvm = PredicateBuilderVMWrapper.create<OrderSecurity, OrderRecordTuplePredicate, OrderRecordTuplePredicate.PredicateTypeOneofCase>(
+               var pvm = PredicateVMWrapper.create<OrderSecurity, OrderRecordTuplePredicate, OrderRecordTuplePredicate.PredicateTypeOneofCase>(
                  OrderRecordTuplePredicateVMFactory.get_oneofs(bus, model), rp => rp.predicate_type_case);
               pvm.selected_predicate_type = pvm.predicate_types.FirstOrDefault();
               return pvm;
            },
            col_id => {
-               var pvm = PredicateBuilderVMWrapper.create<OrderSecurity, OrderRecordTuplePredicate, OrderRecordTuplePredicate.PredicateTypeOneofCase>(
+               var pvm = PredicateVMWrapper.create<OrderSecurity, OrderRecordTuplePredicate, OrderRecordTuplePredicate.PredicateTypeOneofCase>(
                  OrderRecordTuplePredicateVMFactory.get_oneofs(bus, model), rp => rp.predicate_type_case);
               pvm.selected_predicate_type = _corresponding_predicate_type(EnumHelper.parse_or_default<Columns>(col_id));
               return pvm;
            },
-            (gen, anims) => new OrderBookGridSettings(gen, anims.Select(a => new OrderRecordTuplePredicateAnimations(a.predicate_builder, a.cell_animations, a.row_animations, a.sound_notifications))),
-            (notification_service == null) ? null : notification_service.data_cache,
+            (gen, anims) => new OrderBookGridSettings(gen, anims.Select(a => new OrderRecordTuplePredicateAnimations(a.predicate_data, a.cell_animations, a.row_animations, a.sound_notifications))),
+            p => p.create_predicate(notification_service.data_cache),
+            p => p.create_notification_predicate(notification_service.data_cache),
+            notification_service == null ? new Func<IPredicate<OrderSecurity>, SoundNotification, IDisposable>((p, sn) => Disposable.empty) : notification_service.link_to_order,
+            notification_service == null ? new Func<INotificationPredicate<OrderSecurity>, IDisposable>(t => Disposable.empty) : notification_service.link_to_order,
            col_settings_flags);
      }

@@ -275,4 +284,4 @@ namespace mbts.spark {
         }
      }
   }
-}
+}
@@ -1,168 +0,0 @@
-<UserControl x:Class="mbts.spark.OrderBookView" x:ClassModifier="internal"
-             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
-             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
-             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
-             xmlns:sp="clr-namespace:mbts.spark"
-             xmlns:uc="clr-namespace:mbts.ui"
-             xmlns:c="clr-namespace:mbts.ui.controls"
-             xmlns:usp="clr-namespace:mbts.ui.spark"
-             xmlns:uspcv="clr-namespace:mbts.ui.spark.converters"
-             xmlns:sys="clr-namespace:System;assembly=mscorlib"
-             xmlns:order="clr-namespace:bts.api.orderman;assembly=spark_api"
-             mc:Ignorable="d" 
-             d:DesignHeight="600" d:DesignWidth="1080"
-             FocusManager.IsFocusScope="True"
-             Background="{StaticResource CommonBackground}">
-  <UserControl.Resources>
-    <ResourceDictionary>
-      <ResourceDictionary.MergedDictionaries>
-        <ResourceDictionary Source="/view/Controls/DataGridEx/Filters/Views/FilterTemplates.xaml"/>
-      </ResourceDictionary.MergedDictionaries>
-      <uspcv:TickDisplayConverter x:Key="TickDisplayConverter"/>
-      <uspcv:OrderSubTypeDisplayTextConverter x:Key="OrderSubTypeLongDisplayTextConverter" UseLongName="True" />
-      <DataTemplate x:Key="{x:Static sp:OrderBookView.SubTypeFilterTemplateKey}">
-        <usp:FilterContentControl
-          ApplyCommandParameter="{Binding}"
-          ApplyCommand="{x:Static c:DataGridFilterProperties.CommitCommand}"
-          ClearCommandParameter="{Binding}"
-          ClearCommand="{x:Static c:DataGridFilterProperties.ClearCommand}"
-        >
-          <c:ListBoxEx
-            ItemsSource="{Binding items}"
-            Selection="{Binding selected_items}"
-            SelectionMode="Multiple"
-            ItemContainerStyle="{StaticResource ListBoxItemCheckBoxStyle}"
-          >
-            <c:ListBoxEx.ItemTemplate>
-               <DataTemplate>
-               <TextBlock Text="{Binding Converter={StaticResource OrderSubTypeLongDisplayTextConverter}}"/>
-              </DataTemplate>
-            </c:ListBoxEx.ItemTemplate>
-          </c:ListBoxEx>
-        </usp:FilterContentControl>
-      </DataTemplate>
-
-      <Style x:Key="{x:Static sp:OrderBookView.RowStyleKey}" TargetType="ListBoxItem" BasedOn="{StaticResource DIYGridRowStyle}">
-        <Style.Triggers>
-          <MultiDataTrigger>
-            <MultiDataTrigger.Conditions>
-              <Condition Binding="{Binding IsSelected, RelativeSource={RelativeSource Self}}" Value="False"/>
-              <Condition Binding="{Binding status}" Value="{uc:Enum Working, Type=order:OrderStatus}"/>
-            </MultiDataTrigger.Conditions>
-            <MultiDataTrigger.Setters>
-              <Setter Property="Background" Value="{x:Static Member=working_order_background_brush, MemberType={uc:Nested uc:BTSColors.Orders}}"/>
-            </MultiDataTrigger.Setters>
-          </MultiDataTrigger>
-        </Style.Triggers>
-      </Style>
-      <DataTemplate x:Key="{x:Static sp:OrderBookView.RowTemplateKey}">
-        <sp:OrderBookRowView/>
-      </DataTemplate>
-    </ResourceDictionary>
-  </UserControl.Resources>
-  <AdornerDecorator>
-    <Grid>
-      <Grid.RowDefinitions>
-        <RowDefinition />
-        <RowDefinition Height="Auto"/>
-      </Grid.RowDefinitions>
-      <c:DIYGrid
-      x:Name="_grid"
-      Grid.Row="0"
-      Columns="{Binding columns}"
-      CurrentRow="{Binding current_row, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
-      Rows="{Binding rows}"
-      RowStyle="{StaticResource {x:Static sp:OrderBookView.RowStyleKey}}"
-      RowTemplate="{StaticResource {x:Static sp:OrderBookView.RowTemplateKey}}"
-      SelectionHighlight="{Binding grid_settings_manager.selection_highlight, Mode=OneWay}"
-    >
-      <c:DIYGrid.Resources>
-        <ResourceDictionary>
-          <SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Checked.Fill" Color="#FF595959"/>
-          <SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Checked.Stroke" Color="#FF262626"/>
-          <SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Stroke" Color="#FF27C7F7"/>
-          <SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Fill" Color="#FFCCEEFB"/>
-          <SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Checked.Stroke" Color="#FF1CC4F7"/>
-          <SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Checked.Fill" Color="#FF82DFFB"/>
-          <PathGeometry x:Key="TreeArrow" Figures="M0,0 L0,6 L6,0 z"/>
-          <SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Fill" Color="#FFFFFFFF"/>
-          <SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Stroke" Color="#FF818181"/>
-          <Style x:Key="{x:Static sp:OrderBookView.ExpandCollapseToggleStyleKey}" TargetType="{x:Type ToggleButton}">
-            <Setter Property="Focusable" Value="False"/>
-            <Setter Property="Width" Value="16"/>
-            <Setter Property="Height" Value="16"/>
-            <Setter Property="Template">
-              <Setter.Value>
-                <ControlTemplate TargetType="{x:Type ToggleButton}">
-                  <Border Background="Transparent" Height="16" Padding="0,5,5,5" Width="16">
-                    <Path x:Name="ExpandPath" Data="{StaticResource TreeArrow}" Fill="{StaticResource TreeViewItem.TreeArrow.Static.Fill}" Stroke="{StaticResource TreeViewItem.TreeArrow.Static.Stroke}">
-                      <Path.RenderTransform>
-                        <RotateTransform Angle="135" CenterY="3" CenterX="3"/>
-                      </Path.RenderTransform>
-                    </Path>
-                  </Border>
-                  <ControlTemplate.Triggers>
-                    <Trigger Property="IsChecked" Value="True">
-                      <Setter Property="RenderTransform" TargetName="ExpandPath">
-                        <Setter.Value>
-                          <RotateTransform Angle="180" CenterY="3" CenterX="3"/>
-                        </Setter.Value>
-                      </Setter>
-                      <Setter Property="Fill" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.Static.Checked.Fill}"/>
-                      <Setter Property="Stroke" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.Static.Checked.Stroke}"/>
-                    </Trigger>
-                    <Trigger Property="IsMouseOver" Value="True">
-                      <Setter Property="Stroke" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Stroke}"/>
-                      <Setter Property="Fill" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Fill}"/>
-                    </Trigger>
-                    <MultiTrigger>
-                      <MultiTrigger.Conditions>
-                        <Condition Property="IsMouseOver" Value="True"/>
-                        <Condition Property="IsChecked" Value="True"/>
-                      </MultiTrigger.Conditions>
-                      <Setter Property="Stroke" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Checked.Stroke}"/>
-                      <Setter Property="Fill" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Checked.Fill}"/>
-                    </MultiTrigger>
-                  </ControlTemplate.Triggers>
-                </ControlTemplate>
-              </Setter.Value>
-            </Setter>
-          </Style>
-          <Style TargetType="{x:Type ToolTip}">
-            <Style.Triggers>
-              <Trigger Property="Content" Value="{x:Static sys:String.Empty}">
-                <Setter Property="Visibility" Value="Collapsed" />
-              </Trigger>
-              <Trigger Property="Content" Value="{x:Null}">
-                <Setter Property="Visibility" Value="Collapsed" />
-              </Trigger>
-            </Style.Triggers>
-          </Style>
-        </ResourceDictionary>
-      </c:DIYGrid.Resources>
-      <c:DIYGrid.InputBindings>
-        <MouseBinding MouseAction="LeftDoubleClick" Command="{x:Static c:DIYGrid.DefaultRowCommand}"/>
-        <KeyBinding Key="Return" Command="{x:Static c:DIYGrid.DefaultRowCommand}"/>
-      </c:DIYGrid.InputBindings>
-      <c:DIYGrid.CommandBindings>
-        <CommandBinding
-          Command="{x:Static c:DIYGrid.DefaultRowCommand}"
-          Executed="{x:Static c:DIYGrid.DefaultRowActionExecuted}"
-          CanExecute="{x:Static c:DIYGrid.DefaultRowActionCanExecute}"
-        />
-      </c:DIYGrid.CommandBindings>
-    </c:DIYGrid>
-      <StatusBar Grid.Row="1" DockPanel.Dock="Bottom">
-        <StatusBarItem HorizontalAlignment="Right">
-          <TextBlock>
-            <Run Text="Orders:"/>
-            <Run Text="{Binding rows.Count, Mode=OneWay}" />
-            <Run Text="of"/>
-            <Run Text="{Binding rows.total_row_count, Mode=OneWay}" />
-          </TextBlock>
-        </StatusBarItem>
-      </StatusBar>
-    </Grid>
-  </AdornerDecorator>
-</UserControl>
@@ -2,27 +2,31 @@
 using bts.api.orderman;
 using bts.shell;
 using bts.spark;
+using bts.view;
 using mbts.persist;
 using mbts.ui;
 using mbts.ui.converters;
+using mbts.ui.extensions;
 using mbts.ui.spark;
 using mbts.ui.utility;
+using mbts.utils;
 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Reactive.Linq;
 using System.Windows;
 using System.Windows.Data;
+using System.Windows.Input;
 using System.Windows.Media;
-//using IOrderBookWSM = mbts.persist.IWindowSettingsManager<mbts.spark.GridSettingsWithNotifications<mbts.spark.OrderRecordTuple, mbts.OrderRecordTuplePredicate>>;
 using OrderBookGridSettings = bts.shell.OrderBookWindowFactory.OrderBookGridSettings;
 using OrderBookGridSettingsVM = mbts.spark.GridSettingsVM<bts.api.orderman.OrderSecurity, mbts.OrderRecordTuplePredicate, bts.shell.OrderBookWindowFactory.OrderBookGridSettings>;

 namespace mbts.spark {
   internal class OrderBookWindow : SparkWindow<OrderBookWindowFactory.OrderBookStartupData>, ISharedWindow {
-      const string _window_type = "OrderBook", ORDERBOOK_THREAD_ID = "OrderBook", _default_title = "Order Book";
+      const string _window_type = "OrderBook", _default_title = "Order Book";
      readonly INotificationService _notification_service;
      readonly IWindowSettingsManager<OrderBookGridSettings> _settings_manager;
+      IDisposable _attachment_exit_sub;
      OrderBookWindowFactory.OrderBookStartupData _state;
      OrdersModel _model;
      OrderBookVM _vm;
@@ -30,17 +34,6 @@ namespace mbts.spark {
      OrderBookWindowFactory _factory;
      SparkCommand[] _commands;

-      SparkCommand _show_fills_command
-         , _modify_order_command
-         , _cancel_buy_orders_command
-         , _cancel_sell_orders_command
-         , _cancel_all_orders_command
-         , _cancel_selected_orders_command
-         , _recreate_selected_orders_command
-         , _toggle_collapse_all_command
-         , _toggle_expand_all_command
-         , _show_grid_settings_command;
-
      public OrderBookWindow(OrdersModel model, OrderBookWindowFactory factory, IBus bus, INotificationService notification_service,
         OrderBookWindowFactory.OrderBookStartupData state, ImageSource icon, IWindowSettingsManager<OrderBookGridSettings> settings_manager)
         : base(_default_title, bus, factory, SparkCommands.ShowOrders.icon) {
@@ -49,6 +42,7 @@ namespace mbts.spark {
         _notification_service = notification_service;
         _state = state;
         _settings_manager = settings_manager;
+         thread_id = config.Configuration.get<bts.config.MultiThreadedWindows>().order_book ? "OrderBook" : null;
      }

      public override OrderBookWindowFactory.OrderBookStartupData SaveState => _state = _vm?.create();
@@ -61,10 +55,11 @@ namespace mbts.spark {
         + SPARK_MENU_COLLAPSED_WIDTH
         + LAUNCHER_BUTTON_BORDER_WIDTH
         + EXTRA_FOR_NO_HORIZONTAL_SCROLLBAR_WIDTH;
-      public string thread_id => ORDERBOOK_THREAD_ID;
+      public string thread_id { get; }

      public override void Dispose() {
         _commands.OfType<IDisposable>().DisposeAll();
+         Disposable.dispose(ref _attachment_exit_sub);
         Disposable.dispose(ref _vm);
      }

@@ -73,54 +68,86 @@ namespace mbts.spark {
         _vm.load_from(_state);
         _view = new OrderBookView(_vm);

-         _show_fills_command = SparkCommands.ShowFills.complete(() => new FillsWindowFactory.StartupData(_vm.selected_orders.Select(r => r.Key).ToArray()));
+         var show_fills_command = SparkCommands.ShowFills.complete(() => new FillsWindowFactory.StartupData(_vm.selected_orders.Select(r => r.Key).ToArray()));

-         _modify_order_command = SparkCommands.ShowModifyOrder.complete(
-               () => _vm.current_order.Value.Key,
-               can_execute: () => {
-                  if (_vm.current_order.HasValue) {
-                     return _vm.current_order.Value.State.Status == bts.api.orderman.OrderStatus.Working;
-                  }
-                  return false;
-               }
-            );
+         var toggle_right_panel_is_visible_command = new SparkCommandCommand(
+            get_toggle_algo_editor_cmd_title(),
+            Icons.ModifyOrder,
+            _vm.toggle_algo_editor_is_visible_cmd,
+            new KeyGesture(Key.M, ModifierKeys.Control | ModifierKeys.Shift));

-         _cancel_buy_orders_command = SparkCommands.CancelBuyOrders.complete(
+         var cancel_buy_orders_command = SparkCommands.CancelBuyOrders.complete(
            _model.working_orders.Select(os => os.Values.Where(o => o.order.side() == Side.Buy).Select(o => o.order.Key)),
-            wbids => wbids.Any()
+            wbids => wbids.Any(),
+            () => {
+               var resp = BTSMessageBox.Show(
+                  "Are you sure you want to cancel all BUY orders?",
+                  "Cancel Buy Orders",
+                  BTSMessageBoxButtons.Yes | BTSMessageBoxButtons.No,
+                  MessageBoxImage.Question);
+               return resp == BTSMessageBoxButtons.Yes;
+            }
         );

-         _cancel_sell_orders_command = SparkCommands.CancelSellOrders.complete(
+         var cancel_sell_orders_command = SparkCommands.CancelSellOrders.complete(
            _model.working_orders.Select(os => os.Values.Where(o => o.order.side() == Side.Sell).Select(o => o.order.Key)),
-            wasks => wasks.Any()
+            wasks => wasks.Any(),
+            () => {
+               var resp = BTSMessageBox.Show(
+                  "Are you sure you want to cancel all SELL orders?",
+                  "Cancel Sell Orders",
+                  BTSMessageBoxButtons.Yes | BTSMessageBoxButtons.No,
+                  MessageBoxImage.Question);
+               return resp == BTSMessageBoxButtons.Yes;
+            }
         );

-         _cancel_all_orders_command = SparkCommands.CancelOrders.complete(
+         var cancel_all_orders_command = SparkCommands.CancelOrders.complete(
            _model.working_orders.Select(os => os.Select(o => o.Key)),
-            worders => worders.Any()
+            worders => worders.Any(),
+            () => {
+               var resp = BTSMessageBox.Show(
+                  "Are you sure you want to cancel ALL orders?",
+                  "Cancel All Orders",
+                  BTSMessageBoxButtons.Yes | BTSMessageBoxButtons.No,
+                  MessageBoxImage.Question);
+               return resp == BTSMessageBoxButtons.Yes;
+            }
         );

-         _cancel_selected_orders_command = SparkCommands.CancelSelectedOrders.complete(
+         var cancel_selected_orders_command = SparkCommands.CancelSelectedOrders.complete(
            () => _vm.selected_orders.Where(x => x.status() == OrderStatus.Working).Select(x => x.Key),
            can_execute: () => _vm.selected_orders.Any(x => x.status() == OrderStatus.Working)
         );

-         _recreate_selected_orders_command = SparkCommands.RecreateSelectedOrders.complete(
+         var recreate_selected_orders_command = SparkCommands.RecreateSelectedOrders.complete(
             () =>
-               _vm.selected_orders.Where(x => _passes_recreate_search_criteria(x))
+               _vm.selected_orders.Where(x => passes_recreate_search_criteria(x))
                  .Select(x => (x.Def, x.State.Price, x.State.Quantity - x.State.FilledQuantity)),
-            can_execute: () => _vm.selected_orders.Any(x => _passes_recreate_search_criteria(x))
+            can_execute: () => _vm.selected_orders.Any(x => passes_recreate_search_criteria(x))
         );

-         _toggle_collapse_all_command = new SparkCommandCommand("Collapse All",
+         var attach_selected_orders_command = new SparkCommandCommand(
+            "Attach To Selected Orders",
+            Icons.AttachAlgos,
+            new DelegateCommand(_vm.begin_attach_algos, () => _vm.selected_rows.Count > 0),
+            new KeyGesture(Key.A, ModifierKeys.Control | ModifierKeys.Shift));
+
+         var detach_selected_orders_command = new SparkCommandCommand(
+            "Detach And Cancel Selected Orders",
+            Icons.DetachAlgos,
+            new DelegateCommand(_vm.detach_selected_algos, () => _vm.selected_rows.Count > 0),
+            new KeyGesture(Key.D, ModifierKeys.Control | ModifierKeys.Shift));
+
+         var toggle_collapse_all_command = new SparkCommandCommand("Collapse All",
           Icons.RightArrow,
           _vm.collapse_all_rows_command);

-         _toggle_expand_all_command = new SparkCommandCommand("Expand All",
+         var toggle_expand_all_command = new SparkCommandCommand("Expand All",
            Icons.DownArrow,
            _vm.expand_all_rows_command);

-         _show_grid_settings_command = SparkCommands.window_settings_command(new DialogCommand(() => {
+         var show_grid_settings_command = SparkCommands.window_settings_command(new DialogCommand(() => {
            var gs_vm = new WindowSettingsDialogVM<OrderBookGridSettings, OrderBookGridSettingsVM>(
               _settings_manager,
               us => us.order_book_grid,
@@ -145,31 +172,44 @@ namespace mbts.spark {
            return dialog;
         }));

-      _commands = new SparkCommand[] {
-            _show_fills_command,
-            _modify_order_command,
-            _cancel_selected_orders_command,
-            _cancel_buy_orders_command,
-            _cancel_sell_orders_command,
-            _cancel_all_orders_command,
-            _recreate_selected_orders_command,
-            _toggle_collapse_all_command,
-            _toggle_expand_all_command,
-            _show_grid_settings_command
+         _commands = new SparkCommand[] {
+            show_fills_command,
+            toggle_right_panel_is_visible_command,
+            cancel_selected_orders_command,
+            cancel_buy_orders_command,
+            cancel_sell_orders_command,
+            cancel_all_orders_command,
+            recreate_selected_orders_command,
+            attach_selected_orders_command,
+            detach_selected_orders_command,
+            toggle_collapse_all_command,
+            toggle_expand_all_command,
+            show_grid_settings_command
         };
-         _vm.selected_order_changed += _vm_selected_order_changed;
+         _vm.as_demuxer().subscribe<bool>(nameof(OrderBookVM.algo_editor_is_visible))
+            .Subscribe(_ => toggle_right_panel_is_visible_command.title = get_toggle_algo_editor_cmd_title());
+         _vm.selected_order_changed += vm_selected_order_changed;
+         // local methods
+         string get_toggle_algo_editor_cmd_title() =>
+            $"{(_vm.algo_editor_is_visible ? "Hide" : "Show")} Order Params";
+
+         bool passes_recreate_search_criteria(OrderRecordImmutable record) =>
+            (record.status() == OrderStatus.Canceled || record.status() == OrderStatus.Error) &&
+            !record.has_parent() &&
+            record.State.Quantity > record.State.FilledQuantity;
+
+         void vm_selected_order_changed(OrderRecordImmutable? e) {
+            cancel_selected_orders_command.raiseCanExecuteChanged();
+            recreate_selected_orders_command.raiseCanExecuteChanged();
+            attach_selected_orders_command.raiseCanExecuteChanged();
+            detach_selected_orders_command.raiseCanExecuteChanged();
+         }
      }

-      private bool _passes_recreate_search_criteria(OrderRecordImmutable record) {
-         return (record.status() == OrderStatus.Canceled || record.status() == OrderStatus.Error)
-            && !record.has_parent() 
-            && record.State.Quantity > record.State.FilledQuantity;
-      }
-
-      private void _vm_selected_order_changed(OrderRecordImmutable? e) {
-            _modify_order_command.raiseCanExecuteChanged();
-            _cancel_selected_orders_command.raiseCanExecuteChanged();
-            _recreate_selected_orders_command.raiseCanExecuteChanged();
-      }
+      protected override void OnParentViewCreated(SparkWindowView parent_view) =>
+         Disposable.replace(ref _attachment_exit_sub, parent_view.SubscribePreviewKeyDown((s, e) => {
+            if (e.Key == Key.Escape || (e.Key == Key.Z && KeyboardExtensions.IsCtrlDown()))
+               _vm.is_attaching_algos = false;
+         }));
   }
 }
@@ -12,10 +12,11 @@ using mbts.ui.settings;
 using ProtoBuf;
 using System;
 using System.Collections.Generic;
+using System.ComponentModel;
 using System.Reactive.Linq;
 using System.Threading.Tasks;
 using System.Windows;
-using static mbts.spark.OrderBookView;
+using Columns = mbts.spark.OrderBookGridView.ColumnKeys;

 namespace bts.shell {
   internal class OrderBookWindowFactory : ShellWindowFactory<OrderBookWindowFactory.OrderBookStartupData> {
@@ -49,24 +50,57 @@ namespace bts.shell {

      [ProtoContract]
      public class OrderBookStartupData {
-         //[ProtoMember(5)]
-         //public readonly List<SortingCriteria> sort_criteria;
+         const bool _default_algo_editor_is_visible = true;
+         const double
+            _default_right_panel_width = 400,
+            _default_fills_slave_grid_height = 138;
+         // ALREADY USED TAGS
+         // [ProtoMember(5)]
+         // public readonly List<SortingCriteria> sort_criteria;
+
+         // filters
         [ProtoMember(10)]
         public FilterStates filters;
+         // grid
         [ProtoMember(15)]
         [Obsolete]
         public GridSettings grid;
+         // algo editor is visible
+         [ProtoMember(16)]
+         [DefaultValue(_default_algo_editor_is_visible)]
+         public bool algo_editor_is_visible { get; set; }
+         // right panel width
+         [ProtoMember(17)]
+         [DefaultValue(_default_right_panel_width)]
+         public double right_panel_width { get; set; }
+         // fills slave grid height
+         [ProtoMember(18)]
+         [DefaultValue(_default_fills_slave_grid_height)]
+         public double fills_slave_grid_height { get; set; }
+         // fills slave grid is visible
+         [ProtoMember(19)]
+         public bool fills_slave_grid_is_visible { get; set; }
+         // predicate animations
         [ProtoMember(20)]
         [Obsolete]
         List<OrderRecordTuplePredicateAnimations> _predicate_animations;
+         // use defaults
         [ProtoMember(25)]
         public bool use_defaults;

-         public OrderBookStartupData() { }
+         public OrderBookStartupData() {
+            algo_editor_is_visible = _default_algo_editor_is_visible;
+            right_panel_width = _default_right_panel_width;
+            fills_slave_grid_height = _default_fills_slave_grid_height;
+         }

-         public OrderBookStartupData(FilterStates filters, GridSettings grid = default, IEnumerable<OrderRecordTuplePredicateAnimations> predicate_animations = null, bool use_defaults = false) {
+         public OrderBookStartupData(FilterStates filters, GridSettings grid = default, bool algo_editor_is_visible = false, double right_panel_width = 0, double fills_slave_grid_height = 0, bool fills_slave_grid_is_visible = false, IEnumerable<OrderRecordTuplePredicateAnimations> predicate_animations = null, bool use_defaults = false) {
            this.filters = filters;
            this.use_defaults = use_defaults;
+            this.algo_editor_is_visible = algo_editor_is_visible;
+            this.right_panel_width = right_panel_width;
+            this.fills_slave_grid_height = fills_slave_grid_height;
+            this.fills_slave_grid_is_visible = fills_slave_grid_is_visible;
 #pragma warning disable CS0612 // Type or member is obsolete
            this.grid = grid;
            _predicate_animations = new List<OrderRecordTuplePredicateAnimations>();
@@ -83,9 +117,12 @@ namespace bts.shell {

         public static OrderBookStartupData Default =>
           new OrderBookStartupData(
-              new FilterStates {
-                 statuses = new[] { OrderStatus.Working }
-              }, _default_general_grid, use_defaults: true);
+              new FilterStates { statuses = new[] { OrderStatus.Working } },
+              _default_general_grid,
+              _default_algo_editor_is_visible,
+              _default_right_panel_width,
+              _default_fills_slave_grid_height,
+              use_defaults: true);

         public static OrderBookGridSettings DefaultGrid => new OrderBookGridSettings(_default_general_grid);

@@ -115,6 +152,7 @@ namespace bts.shell {
            public static GridColumnSettings security_key => new GridColumnSettings(Columns.SecurityKey.ToString(), DIYGrid.DefaultColumnHeaders.SecurityKey, is_visible: false, width: DIYGrid.DefaultColumnWidths.SecurityKey);
            public static GridColumnSettings order_key => new GridColumnSettings(Columns.OrderKey.ToString(), DIYGrid.DefaultColumnHeaders.OrderKey, width: DIYGrid.DefaultColumnWidths.OrderKey);
            public static GridColumnSettings parent_key => new GridColumnSettings(Columns.ParentKey.ToString(), "Parent Key", width: DIYGrid.DefaultColumnWidths.ParentKey);
+            public static GridColumnSettings attached_target_order_key => new GridColumnSettings(Columns.AttachedTargetOrderKey.ToString(), DIYGrid.DefaultColumnHeaders.AttachedTargetOrderKey, width: DIYGrid.DefaultColumnWidths.ParentKey);

            public static IEnumerable<SortingCriteria> sorting_criterion {
               get {
@@ -145,11 +183,12 @@ namespace bts.shell {
                  yield return security_key;
                  yield return order_key;
                  yield return parent_key;
+                  yield return attached_target_order_key;
               }
            }

            private static HashSet<GridColumnSettings> _mini_mode_columns_to_hide = new HashSet<GridColumnSettings> {
-               time_created, exchange, sub_type, quantity, price, avg_price, last_price, status, last_message, security_key, order_key, parent_key
+               time_created, exchange, sub_type, quantity, price, avg_price, last_price, status, last_message, security_key, order_key, parent_key, attached_target_order_key
            };

            public static IEnumerable<GridColumnSettings> mini {
@@ -208,11 +247,17 @@ namespace bts.shell {
         public api.orderman.OrderSubType[] order_sub_types;
         [ProtoMember(20)]
         public string[] symbols;
+         [ProtoMember(21)]
+         public string parent_key_regex;
+         [ProtoMember(22)]
+         public string attached_target_order_key_regex;

         public bool Equals(FilterStates other) =>
            other != null &&
            security_criteria.safe_equals(other.security_criteria) &&
            order_key_regex == other.order_key_regex &&
+            parent_key_regex == other.parent_key_regex &&
+            attached_target_order_key_regex == other.attached_target_order_key_regex &&
            time_created.Equals(other.time_created) &&
            EqualityComparer.safe_sequence_equals(users, other.users) &&
            EqualityComparer.safe_sequence_equals(accounts, other.accounts) &&
@@ -230,6 +275,32 @@ namespace bts.shell {
            last_change.Equals(other.last_change) &&
            EqualityComparer.safe_sequence_equals(order_sub_types, other.order_sub_types) &&
            EqualityComparer.safe_sequence_equals(symbols, other.symbols);
+
+         public override bool Equals(object obj) => Equals(obj as FilterStates);
+
+         public override int GetHashCode() =>
+            EqualityComparer.aggregate_hash(
+               security_criteria?.GetHashCode() ?? 0,
+               order_key_regex?.GetHashCode() ?? 0,
+               parent_key_regex?.GetHashCode() ?? 0,
+               attached_target_order_key_regex?.GetHashCode() ?? 0,
+               time_created.GetHashCode(),
+               EqualityComparer.safe_aggregate_hash(users),
+               EqualityComparer.safe_aggregate_hash(accounts),
+               EqualityComparer.safe_aggregate_hash(exchanges),
+               EqualityComparer.safe_aggregate_hash(tifs),
+               EqualityComparer.safe_aggregate_hash(order_types),
+               EqualityComparer.safe_aggregate_hash(sides),
+               qty?.GetHashCode() ?? 0,
+               price?.GetHashCode() ?? 0,
+               qty_filled?.GetHashCode() ?? 0,
+               avg_price?.GetHashCode() ?? 0,
+               last_price?.GetHashCode() ?? 0,
+               EqualityComparer.safe_aggregate_hash(statuses),
+               exchange_message_regex?.GetHashCode() ?? 0,
+               last_change.GetHashCode(),
+               EqualityComparer.safe_aggregate_hash(order_sub_types),
+               EqualityComparer.safe_aggregate_hash(symbols));
      }

      [ProtoContract]
@@ -240,7 +311,7 @@ namespace bts.shell {
         List<OrderRecordTuplePredicateAnimations> _predicate_animations;

         public OrderBookGridSettings() { }
-         public OrderBookGridSettings(GridSettings general = default, IEnumerable<OrderRecordTuplePredicateAnimations> predicate_animations = null) {
+         public OrderBookGridSettings(GridSettings general = default, IEnumerable<OrderRecordTuplePredicateAnimations> predicate_animations = null, double right_panel_width = double.NaN) {
            this.general = general;
            _predicate_animations = new List<OrderRecordTuplePredicateAnimations>();
            if (predicate_animations != null)
@@ -0,0 +1,63 @@
+using mbts.ui;
+using mbts.ui.controls;
+using mbts.ui.controls.adorners;
+using mbts.ui.extensions;
+using System;
+using System.Reactive.Linq;
+using System.Windows;
+using System.Windows.Input;
+
+namespace mbts.spark {
+   partial class OrderBookView {
+      public class OrderBookAttachmentTargetAdorner : DIYGridRowHighlighterAdorner, IDisposable {
+         IDisposable _attach_op;
+         bool _is_active, _is_disposed;
+
+         #region IsActive
+         public static readonly DependencyProperty IsActiveProperty =
+            WPFHelper.create_dp<bool, OrderBookAttachmentTargetAdorner>(
+               nameof(IsActive),
+               FrameworkPropertyMetadataOptions.AffectsRender,
+               (o, v) => {
+                  o._is_active = v;
+                  Disposable.dispose(ref o._attach_op);
+                  if (v && !o._is_disposed) {
+                     o.IsHitTestVisible = true;
+                     o._attach_op = Disposable.Create(
+                        o.SubscribePreviewMouseDown((s, e) => {
+                           if (e.ChangedButton == MouseButton.Left) {
+                              if (e.ClickCount > 1 && o.TargetRow is OrderBookRowVM r) {
+                                 e.Handled = true;
+                                 o._raise_target_row_selected(r);
+                              }
+                           }
+                        }),
+                        o.AdornedElement.SubscribeMouseHoverRow<OrderBookRowVM>().Subscribe(row => o.TargetRow = row));
+                  } else {
+                     o.IsHitTestVisible = false;
+                     o.TargetRow = null;
+                  }
+               },
+               false);
+
+         public bool IsActive {
+            get => (bool)GetValue(IsActiveProperty);
+            set => SetValue(IsActiveProperty, value);
+         }
+
+         public event Action<OrderBookRowVM> TargetRowSelected;
+         #endregion
+
+         public OrderBookAttachmentTargetAdorner(DIYGrid grid) : base(grid) { }
+
+         public void Dispose() {
+            if (!_is_disposed) {
+               _is_disposed = true;
+               Disposable.dispose(ref _attach_op);
+            }
+         }
+
+         void _raise_target_row_selected(OrderBookRowVM row) => TargetRowSelected?.Invoke(row);
+      }
+   }
+} 
@@ -0,0 +1,132 @@
+<c:DIYGrid
+  x:Class="mbts.spark.OrderBookGridView"
+  x:ClassModifier="internal"
+  x:Name="_grid"
+  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+  xmlns:order="clr-namespace:bts.api.orderman;assembly=spark_api"
+  xmlns:sp="clr-namespace:mbts.spark"
+  xmlns:u="clr-namespace:mbts.ui"
+  xmlns:c="clr-namespace:mbts.ui.controls"
+  xmlns:usp="clr-namespace:mbts.ui.spark"
+  xmlns:uspcv="clr-namespace:mbts.ui.spark.converters"
+  xmlns:sys="clr-namespace:System;assembly=mscorlib"
+>
+  <c:DIYGrid.Resources>
+    <ResourceDictionary>
+      <ResourceDictionary.MergedDictionaries>
+        <ResourceDictionary Source="/view/Controls/DataGridEx/Filters/Views/FilterTemplates.xaml"/>
+      </ResourceDictionary.MergedDictionaries>
+      <!--Primitive Resources (Brushes, Colors, etc.)-->
+      <SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Checked.Fill" Color="#FF595959"/>
+      <SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Checked.Stroke" Color="#FF262626"/>
+      <SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Stroke" Color="#FF27C7F7"/>
+      <SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Fill" Color="#FFCCEEFB"/>
+      <SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Checked.Stroke" Color="#FF1CC4F7"/>
+      <SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Checked.Fill" Color="#FF82DFFB"/>
+      <SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Fill" Color="#FFFFFFFF"/>
+      <SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Stroke" Color="#FF818181"/>
+      <PathGeometry x:Key="TreeArrow" Figures="M0,0 L0,6 L6,0 z"/>
+      <!--Converters-->
+      <uspcv:OrderSubTypeDisplayTextConverter x:Key="OrderSubTypeLongDisplayTextConverter" UseLongName="True" />
+      <!--DataTemplates-->
+      <DataTemplate x:Key="{x:Static sp:OrderBookGridView.SubTypeFilterTemplateKey}">
+        <usp:FilterContentControl
+          ApplyCommandParameter="{Binding}"
+          ApplyCommand="{x:Static c:DataGridFilterProperties.CommitCommand}"
+          ClearCommandParameter="{Binding}"
+          ClearCommand="{x:Static c:DataGridFilterProperties.ClearCommand}"
+        >
+          <c:ListBoxEx
+            ItemsSource="{Binding items}"
+            Selection="{Binding selected_items}"
+            SelectionMode="Multiple"
+            ItemContainerStyle="{StaticResource ListBoxItemCheckBoxStyle}"
+          >
+            <c:ListBoxEx.ItemTemplate>
+              <DataTemplate>
+                <TextBlock Text="{Binding Converter={StaticResource OrderSubTypeLongDisplayTextConverter}}"/>
+              </DataTemplate>
+            </c:ListBoxEx.ItemTemplate>
+          </c:ListBoxEx>
+        </usp:FilterContentControl>
+      </DataTemplate>
+      <!--Styles-->
+      <Style x:Key="{x:Static sp:OrderBookGridView.ExpandCollapseToggleStyleKey}" TargetType="{x:Type ToggleButton}">
+        <Setter Property="Focusable" Value="False"/>
+        <Setter Property="Width" Value="16"/>
+        <Setter Property="Height" Value="16"/>
+        <Setter Property="Template">
+          <Setter.Value>
+            <ControlTemplate TargetType="{x:Type ToggleButton}">
+              <Border Background="Transparent" Height="16" Padding="0,5,5,5" Width="16">
+                <Path x:Name="ExpandPath" Data="{StaticResource TreeArrow}" Fill="{StaticResource TreeViewItem.TreeArrow.Static.Fill}" Stroke="{StaticResource TreeViewItem.TreeArrow.Static.Stroke}">
+                  <Path.RenderTransform>
+                    <RotateTransform Angle="135" CenterY="3" CenterX="3"/>
+                  </Path.RenderTransform>
+                </Path>
+              </Border>
+              <ControlTemplate.Triggers>
+                <Trigger Property="IsChecked" Value="True">
+                  <Setter Property="RenderTransform" TargetName="ExpandPath">
+                    <Setter.Value>
+                      <RotateTransform Angle="180" CenterY="3" CenterX="3"/>
+                    </Setter.Value>
+                  </Setter>
+                  <Setter Property="Fill" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.Static.Checked.Fill}"/>
+                  <Setter Property="Stroke" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.Static.Checked.Stroke}"/>
+                </Trigger>
+                <Trigger Property="IsMouseOver" Value="True">
+                  <Setter Property="Stroke" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Stroke}"/>
+                  <Setter Property="Fill" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Fill}"/>
+                </Trigger>
+                <MultiTrigger>
+                  <MultiTrigger.Conditions>
+                    <Condition Property="IsMouseOver" Value="True"/>
+                    <Condition Property="IsChecked" Value="True"/>
+                  </MultiTrigger.Conditions>
+                  <Setter Property="Stroke" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Checked.Stroke}"/>
+                  <Setter Property="Fill" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Checked.Fill}"/>
+                </MultiTrigger>
+              </ControlTemplate.Triggers>
+            </ControlTemplate>
+          </Setter.Value>
+        </Setter>
+      </Style>
+      <Style TargetType="{x:Type ToolTip}">
+        <Style.Triggers>
+          <Trigger Property="Content" Value="{x:Static sys:String.Empty}">
+            <Setter Property="Visibility" Value="Collapsed" />
+          </Trigger>
+          <Trigger Property="Content" Value="{x:Null}">
+            <Setter Property="Visibility" Value="Collapsed" />
+          </Trigger>
+        </Style.Triggers>
+      </Style>
+    </ResourceDictionary>
+  </c:DIYGrid.Resources>
+  <c:DIYGrid.InputBindings>
+    <MouseBinding MouseAction="LeftDoubleClick" Command="{x:Static c:DIYGrid.DefaultRowCommand}"/>
+    <KeyBinding Key="Return" Command="{x:Static c:DIYGrid.DefaultRowCommand}"/>
+  </c:DIYGrid.InputBindings>
+  <c:DIYGrid.RowStyle>
+    <Style TargetType="ListBoxItem" BasedOn="{StaticResource DIYGridRowStyle}">
+      <Style.Triggers>
+        <MultiDataTrigger>
+          <MultiDataTrigger.Conditions>
+            <Condition Binding="{Binding IsSelected, RelativeSource={RelativeSource Self}}" Value="False"/>
+            <Condition Binding="{Binding status}" Value="{u:Enum Working, Type=order:OrderStatus}"/>
+          </MultiDataTrigger.Conditions>
+          <MultiDataTrigger.Setters>
+            <Setter Property="Background" Value="{x:Static Member=working_order_background_brush, MemberType={u:Nested u:BTSColors.Orders}}"/>
+          </MultiDataTrigger.Setters>
+        </MultiDataTrigger>
+      </Style.Triggers>
+    </Style>
+  </c:DIYGrid.RowStyle>
+  <c:DIYGrid.RowTemplate>
+    <DataTemplate>
+      <sp:OrderBookRowView/>
+    </DataTemplate>
+  </c:DIYGrid.RowTemplate>
+</c:DIYGrid>
@@ -1,11 +1,7 @@
 using mbts.ui.controls;
-using System.Windows.Controls;

 namespace mbts.spark {
-   internal partial class OrderBookView : UserControl {
-      // IMPORTANT: these enums are stored as strings in the general-purpose GridColumnSettings proto, and are used to ID THE COLUMNS!
-      // Do NOT RENAME them!  However, if you must, be sure to write an IShellWindowMigrationRule or something to account for backwards compatability.
-      public enum Columns { Security, Symbol, Time, LastChange, User, Account, Exchange, TimeInForce, OrderType, SubType, Side, Size, Price, Filled, AvgFilled, LastPrice, Status, LastMessage, SecurityKey, OrderKey, ParentKey, Cancel, EditableQty, EditablePrice }
+   internal partial class OrderBookGridView : DIYGrid {
      public const string
         SubTypeFilterTemplateKey = "SubTypeFilterTemplate",
         ExpandCollapseToggleStyleKey = "ExpandCollapseToggleStyle",
@@ -14,13 +10,41 @@ namespace mbts.spark {
         CVRowStyleKey = "CVRowStyle",
         CVRowTemplateKey = "CVRowTemplateKey";

-      public OrderBookView(OrderBookVM vm) {
-         InitializeComponent();
-         DataContext = vm;
+      // IMPORTANT: these enums are stored as strings in the general-purpose GridColumnSettings proto, and are used to ID THE COLUMNS!
+      // Do NOT RENAME them!  However, if you must, be sure to write an IShellWindowMigrationRule or something to account for backwards compatability.
+      public enum ColumnKeys {
+         Security,
+         Symbol,
+         Time,
+         LastChange,
+         User,
+         Account,
+         Exchange,
+         TimeInForce,
+         OrderType,
+         SubType,
+         Side,
+         Size,
+         Price,
+         Filled,
+         AvgFilled,
+         LastPrice,
+         Status,
+         LastMessage,
+         SecurityKey,
+         OrderKey,
+         ParentKey,
+         AttachedTargetOrderKey,
+         Cancel,
+         EditableQty,
+         EditablePrice
      }
+
+      public OrderBookGridView() =>
+         InitializeComponent();
   }

-   class OrderBookRowView : DIYGrid.HighPerformanceRow<OrderBookRowVM, OrderBookView.Columns> {
+   class OrderBookRowView : DIYGrid.HighPerformanceRow<OrderBookRowVM, OrderBookGridView.ColumnKeys> {
      public OrderBookRowView() : base() { }
   }
 }
@@ -0,0 +1,407 @@
+<UserControl
+  x:Class="mbts.spark.OrderBookView"
+  x:ClassModifier="internal"
+  x:Name="Root"
+  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+  xmlns:sp="clr-namespace:mbts.spark"
+  xmlns:u="clr-namespace:mbts.ui"
+  xmlns:c="clr-namespace:mbts.ui.controls"
+  xmlns:cv="clr-namespace:mbts.ui.converters"
+  xmlns:usp="clr-namespace:mbts.ui.spark"
+  xmlns:sys="clr-namespace:System;assembly=mscorlib"
+  Grid.Row="0"
+  FocusManager.IsFocusScope="True"
+  Background="{StaticResource CommonBackground}"
+>
+  <UserControl.Resources>
+    <ResourceDictionary>
+      <ResourceDictionary.MergedDictionaries>
+        <ResourceDictionary Source="/view/Controls/DataGridEx/Filters/Views/FilterTemplates.xaml"/>
+        <ResourceDictionary Source="/Modules/Trading/OrderBook/View/OrderParamsPanel.xaml"/>
+      </ResourceDictionary.MergedDictionaries>
+      <sys:Double x:Key="GridSplitterWidth">5</sys:Double>
+      <sys:Double x:Key="FillsSlaveGridMinHeight">64</sys:Double>
+      <SolidColorBrush x:Key="AlgoAttachmentBackground" Color="#55009500"/>
+      <cv:GridLengthConverter x:Key="GridLengthPixelConverter" UnitType="Pixel"/>
+      <Style TargetType="GridSplitter">
+        <Style.Triggers>
+          <Trigger Property="IsMouseOver" Value="True">
+            <Setter Property="Background" Value="{StaticResource Control.MediumGrayBrush}"/>
+            <Setter Property="BorderBrush" Value="{StaticResource Control.MediumGrayBrush}"/>
+          </Trigger>
+        </Style.Triggers>
+      </Style>
+      <Style x:Key="{x:Static usp:OrderParamsPanel.BestBidPriceButtonStyleKey}" TargetType="Button" BasedOn="{StaticResource {x:Type Button}}">
+        <Setter Property="ToolTip">
+          <Setter.Value>
+            <ToolTip DataContext="{Binding PlacementTarget.Parent.DataContext, RelativeSource={RelativeSource Self}}">
+              <TextBlock Text="{Binding security, StringFormat='Best Bid Price ({0})'}"/>
+            </ToolTip>
+          </Setter.Value>
+        </Setter>
+      </Style>
+      <Style x:Key="{x:Static usp:OrderParamsPanel.BestBidSizeButtonStyleKey}" TargetType="Button" BasedOn="{StaticResource {x:Type Button}}">
+        <Setter Property="Command" Value="{Binding DataContext.size_calculator.set_value_command, RelativeSource={RelativeSource AncestorType=usp:OrderParamsPanel}}"/>
+        <Setter Property="CommandParameter" Value="{Binding BestBidSize, RelativeSource={RelativeSource AncestorType=usp:OrderParamsPanel}}"/>
+        <Setter Property="ToolTip">
+          <Setter.Value>
+            <ToolTip DataContext="{Binding PlacementTarget.Parent.DataContext, RelativeSource={RelativeSource Self}}">
+              <TextBlock Text="{Binding security, StringFormat='Best Bid Size ({0})'}"/>
+            </ToolTip>
+          </Setter.Value>
+        </Setter>
+      </Style>
+      <Style x:Key="{x:Static usp:OrderParamsPanel.BestAskPriceButtonStyleKey}" TargetType="Button" BasedOn="{StaticResource {x:Type Button}}">
+        <Setter Property="ToolTip">
+          <Setter.Value>
+            <ToolTip DataContext="{Binding PlacementTarget.Parent.DataContext, RelativeSource={RelativeSource Self}}">
+              <TextBlock Text="{Binding security, StringFormat='Best Ask Price ({0})'}"/>
+            </ToolTip>
+          </Setter.Value>
+        </Setter>
+      </Style>
+      <Style x:Key="{x:Static usp:OrderParamsPanel.BestAskSizeButtonStyleKey}" TargetType="Button" BasedOn="{StaticResource {x:Type Button}}">
+        <Setter Property="Command" Value="{Binding DataContext.size_calculator.set_value_command, RelativeSource={RelativeSource AncestorType=usp:OrderParamsPanel}}"/>
+        <Setter Property="CommandParameter" Value="{Binding BestAskSize, RelativeSource={RelativeSource AncestorType=usp:OrderParamsPanel}}"/>
+        <Setter Property="ToolTip">
+          <Setter.Value>
+            <ToolTip DataContext="{Binding PlacementTarget.Parent.DataContext, RelativeSource={RelativeSource Self}}">
+              <TextBlock Text="{Binding security, StringFormat='Best Ask Size ({0})'}"/>
+            </ToolTip>
+          </Setter.Value>
+        </Setter>
+      </Style>
+      <Style x:Key="{x:Static usp:OrderParamsPanel.SizeCalculatorButtonStyleKey}" TargetType="Button" BasedOn="{StaticResource {x:Type Button}}">
+        <Setter Property="Command" Value="{Binding DataContext.size_calculator.click, RelativeSource={RelativeSource AncestorType=usp:OrderParamsPanel}}"/>
+        <Setter Property="CommandParameter" Value="{Binding}"/>
+      </Style>
+    </ResourceDictionary>
+  </UserControl.Resources>
+  <AdornerDecorator>
+    <Grid x:Name="ContentRoot">
+      <u:StateManager.Groups>
+        <u:StateGroupsManager Target="{Binding Source={u:DirectReference ContentRoot}}">
+          <u:StateDefinitionCollection>
+            <u:StateDefinition>
+              <MultiBinding Converter="{x:Static sp:OrderBookView.RightPanelVisualStateConverter}">
+                <Binding Path="DataContext.algo_editor_is_visible" Source="{u:DirectReference ContentRoot}"/>
+                <Binding Path="DataContext.is_attaching_algos" Source="{u:DirectReference ContentRoot}"/>
+              </MultiBinding>
+            </u:StateDefinition>
+          </u:StateDefinitionCollection>
+        </u:StateGroupsManager>
+      </u:StateManager.Groups>
+      <VisualStateManager.VisualStateGroups>
+        <VisualStateGroup Name="{x:Static GroupName, MemberType={u:Nested sp:OrderBookView.VisualStateNames.RightPanel}}">
+          <!--Normal State-->
+          <VisualState Name="{x:Static Normal, MemberType={u:Nested sp:OrderBookView.VisualStateNames.RightPanel}}"/>
+          <!--Attach Orders State-->
+          <VisualState Name="{x:Static AttachOrders, MemberType={u:Nested sp:OrderBookView.VisualStateNames.RightPanel}}">
+            <Storyboard>
+              <!--Orders Grid-->
+              <Int32Animation Storyboard.TargetName="orders_grid" Storyboard.TargetProperty="(Grid.ColumnSpan)" BeginTime="0" Duration="0" To="1"/>
+              <ObjectAnimationUsingKeyFrames Storyboard.TargetName="orders_grid" Storyboard.TargetProperty="(FrameworkElement.Cursor)">
+                <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Cursors.Pen}"/>
+              </ObjectAnimationUsingKeyFrames>
+              <DoubleAnimationUsingKeyFrames Storyboard.TargetName="attachment_grid_overlay_border" Storyboard.TargetProperty="(UIElement.Opacity)">
+                <DiscreteDoubleKeyFrame KeyTime="0" Value="1"/>
+              </DoubleAnimationUsingKeyFrames>
+              <!--Right Panel-->
+              <ObjectAnimationUsingKeyFrames Storyboard.TargetName="right_panel_host" Storyboard.TargetProperty="(UIElement.Visibility)">
+                <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Visible}"/>
+              </ObjectAnimationUsingKeyFrames>
+              <ObjectAnimationUsingKeyFrames Storyboard.TargetName="right_panel_width_splitter" Storyboard.TargetProperty="(UIElement.Visibility)">
+                <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Visible}"/>
+              </ObjectAnimationUsingKeyFrames>
+              <!--Modify Orders Controls-->
+              <ObjectAnimationUsingKeyFrames Storyboard.TargetName="order_params_group_box" Storyboard.TargetProperty="(UIElement.Visibility)">
+                <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Collapsed}"/>
+              </ObjectAnimationUsingKeyFrames>
+              <ObjectAnimationUsingKeyFrames Storyboard.TargetName="modify_orders_button" Storyboard.TargetProperty="(UIElement.Visibility)">
+                <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Collapsed}"/>
+              </ObjectAnimationUsingKeyFrames>
+              <!--Fills Slave Grid-->
+              <ObjectAnimationUsingKeyFrames Storyboard.TargetName="fills_toggle_hyperlink" Storyboard.TargetProperty="(UIElement.Visibility)">
+                <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Collapsed}"/>
+              </ObjectAnimationUsingKeyFrames>
+              <!--Attach Orders Controls-->
+              <ObjectAnimationUsingKeyFrames Storyboard.TargetName="attach_orders_dialog_skirt" Storyboard.TargetProperty="(UIElement.Visibility)">
+                <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Visible}"/>
+              </ObjectAnimationUsingKeyFrames>
+              <ObjectAnimationUsingKeyFrames Storyboard.TargetName="attachment_content_root" Storyboard.TargetProperty="(UIElement.Visibility)">
+                <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Visible}"/>
+              </ObjectAnimationUsingKeyFrames>
+            </Storyboard>
+          </VisualState>
+          <!--Modify Orders State-->
+          <VisualState Name="{x:Static ModifyOrders, MemberType={u:Nested sp:OrderBookView.VisualStateNames.RightPanel}}">
+            <Storyboard>
+              <!--Orders Grid-->
+              <Int32Animation Storyboard.TargetName="orders_grid" Storyboard.TargetProperty="(Grid.ColumnSpan)" BeginTime="0" Duration="0" To="1"/>
+              <!--Right Panel-->
+              <ObjectAnimationUsingKeyFrames Storyboard.TargetName="right_panel_host" Storyboard.TargetProperty="(UIElement.Visibility)">
+                <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Visible}"/>
+              </ObjectAnimationUsingKeyFrames>
+              <ObjectAnimationUsingKeyFrames Storyboard.TargetName="right_panel_width_splitter" Storyboard.TargetProperty="(UIElement.Visibility)">
+                <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Visible}"/>
+              </ObjectAnimationUsingKeyFrames>
+            </Storyboard>
+          </VisualState>
+        </VisualStateGroup>
+      </VisualStateManager.VisualStateGroups>
+      <Grid.RowDefinitions>
+        <RowDefinition Height="*"/>
+        <RowDefinition Height="Auto"/>
+      </Grid.RowDefinitions>
+      <Grid.ColumnDefinitions>
+        <ColumnDefinition Width="*"/>
+        <ColumnDefinition Width="{Binding right_panel_width, Converter={StaticResource GridLengthPixelConverter}, Mode=TwoWay}"/>
+      </Grid.ColumnDefinitions>
+      <sp:OrderBookGridView
+        x:Name="orders_grid"
+        Grid.ColumnSpan="2"
+        Background="Transparent"
+        Columns="{Binding columns}"
+        CurrentRow="{Binding current_row, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
+        Rows="{Binding rows}"
+        SelectionHighlight="{Binding grid_settings_manager.selection_highlight, Mode=OneWay}"
+        Cursor="Arrow"
+      />
+      <Border
+        x:Name="attachment_grid_overlay_border"
+        Panel.ZIndex="1"
+        Width="{Binding ActualWidth, ElementName=orders_grid}"
+        Height="{Binding ActualHeight, ElementName=orders_grid}"
+        Background="{StaticResource AlgoAttachmentBackground}"
+        Opacity="0"
+        IsHitTestVisible="False"
+      />
+      <GridSplitter
+        x:Name="right_panel_width_splitter"
+        Grid.Column="1"
+        Panel.ZIndex="1"
+        HorizontalAlignment="Left"
+        VerticalAlignment="Stretch"
+        Width="{StaticResource GridSplitterWidth}"
+        BorderThickness="1,0,0,0"
+        Visibility="Collapsed"
+      />
+      <Grid x:Name="right_panel_host" Grid.Column="1" Visibility="Collapsed">
+        <Grid.RowDefinitions>
+          <RowDefinition Height="*"/>
+          <RowDefinition Height="Auto"/>
+        </Grid.RowDefinitions>
+        <Grid x:Name="right_panel_content_root">
+          <u:StateManager.Groups>
+            <u:StateGroupsManager Target="{Binding Source={u:DirectReference right_panel_content_root}}">
+              <u:StateDefinitionCollection>
+                <u:StateDefinition>
+                  <MultiBinding Converter="{x:Static sp:OrderBookView.FillsSlaveGridStateConverter}">
+                    <Binding Path="DataContext.fills_slave_grid_is_visible" Source="{u:DirectReference right_panel_content_root}"/>
+                    <Binding Path="DataContext.is_attaching_algos" Source="{u:DirectReference right_panel_content_root}"/>
+                  </MultiBinding>
+                </u:StateDefinition>
+              </u:StateDefinitionCollection>
+            </u:StateGroupsManager>
+          </u:StateManager.Groups>
+          <VisualStateManager.VisualStateGroups>
+            <VisualStateGroup Name="{x:Static GroupName, MemberType={u:Nested sp:OrderBookView.VisualStateNames.FillsPanel}}">
+              <VisualState Name="{x:Static Active, MemberType={u:Nested sp:OrderBookView.VisualStateNames.FillsPanel}}">
+                <Storyboard>
+                  <ObjectAnimationUsingKeyFrames Storyboard.TargetName="fills_grid" Storyboard.TargetProperty="(UIElement.Visibility)">
+                    <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Visible}"/>
+                  </ObjectAnimationUsingKeyFrames>
+                  <ObjectAnimationUsingKeyFrames Storyboard.TargetName="fills_order_params_splitter" Storyboard.TargetProperty="(UIElement.Visibility)">
+                    <DiscreteObjectKeyFrame KeyTime="0" Value="{x:Static Visibility.Visible}"/>
+                  </ObjectAnimationUsingKeyFrames>
+                  <Int32AnimationUsingKeyFrames Storyboard.TargetName="order_params_group_box" Storyboard.TargetProperty="(Grid.Row)">
+                    <DiscreteInt32KeyFrame KeyTime="0" Value="2"/>
+                  </Int32AnimationUsingKeyFrames>
+                  <Int32AnimationUsingKeyFrames Storyboard.TargetName="order_params_group_box" Storyboard.TargetProperty="(Grid.RowSpan)">
+                    <DiscreteInt32KeyFrame KeyTime="0" Value="1"/>
+                  </Int32AnimationUsingKeyFrames>
+                </Storyboard>
+              </VisualState>
+              <VisualState Name="{x:Static Inactive, MemberType={u:Nested sp:OrderBookView.VisualStateNames.FillsPanel}}"/>
+            </VisualStateGroup>
+          </VisualStateManager.VisualStateGroups>
+          <Grid.ColumnDefinitions>
+            <ColumnDefinition Width="{Binding Source={StaticResource GridSplitterWidth}}"/>
+            <ColumnDefinition Width="*"/>
+          </Grid.ColumnDefinitions>
+          <Grid.RowDefinitions>
+            <RowDefinition Height="Auto"/>
+            <RowDefinition MinHeight="{StaticResource FillsSlaveGridMinHeight}" Height="{Binding fills_slave_grid_height, Converter={StaticResource GridLengthPixelConverter}, Mode=TwoWay}" MaxHeight="{Binding ActualHeight, ElementName=right_panel_content_root, Converter={x:Static sp:OrderBookView.FillsSlaveGridMaxHeightConverter}}"/>
+            <RowDefinition MinHeight="{x:Static sp:OrderBookView.GridSplitterHeight}" Height="*"/>
+          </Grid.RowDefinitions>
+          <TextBlock x:Name="fills_toggle_hyperlink" Grid.Column="1">
+            <TextBlock.Margin>
+              <Thickness Left="{StaticResource DialogSkirtPadding.Left}" Top="4"/>
+            </TextBlock.Margin>
+          <Hyperlink Command="{Binding toggle_fills_slave_grid_is_visible_cmd}">
+            <Hyperlink.Inlines>
+              <Run Text="{Binding current_row, Converter={x:Static sp:OrderBookView.OrderDescriptionConverter}, Mode=OneWay}"/>
+            </Hyperlink.Inlines>
+          </Hyperlink>
+          </TextBlock>
+
+          <c:DIYGrid x:Name="fills_grid" Grid.Column="1" Grid.Row="1" Columns="{Binding fills_vm.columns}" Rows="{Binding fills_vm.rows}" Visibility="Collapsed">
+            <c:DIYGrid.Margin>
+              <Thickness Bottom="{x:Static sp:OrderBookView.GridSplitterHeight}"/>
+            </c:DIYGrid.Margin>
+            <c:DIYGrid.RowTemplate>
+              <DataTemplate>
+                <usp:FillsRowView/>
+              </DataTemplate>
+            </c:DIYGrid.RowTemplate>
+          </c:DIYGrid>
+          <GridSplitter
+            x:Name="fills_order_params_splitter"
+            Grid.Column="1"
+            Grid.Row="1"
+            Panel.ZIndex="1"
+            HorizontalAlignment="Stretch"
+            VerticalAlignment="Bottom"
+            Height="{x:Static sp:OrderBookView.GridSplitterHeight}"
+            BorderThickness="0,1,0,0"
+            Visibility="Collapsed"
+          />
+          <GroupBox
+            x:Name="order_params_group_box"
+            Grid.Column="1"
+            Grid.Row="1"
+            Grid.RowSpan="2"
+            Padding="12"
+            BorderThickness="1"
+            HorizontalAlignment="Left"
+            Header="Order Parameters"
+            HeaderTemplate="{StaticResource BoldHeaderTemplate}"
+          >
+            <usp:OrderParamsPanel
+              x:Name="order_params_panel"
+              DataContext="{Binding order_mod_vm}"
+              Price="{Binding price}"
+              Size="{Binding size_calculator.value}"
+              Accounts="{Binding accounts}"
+              SelectedAccount="{Binding selected_account}"
+              BestBidPrice="{Binding bbo.bid}"
+              BestBidSize="{Binding bbo.bid_size}"
+              BestAskPrice="{Binding bbo.ask}"
+              BestAskSize="{Binding bbo.ask_size}"
+              SizePresets="{Binding size_calculator.buttons}"
+              Security="{Binding security}"
+              AlgoVM="{Binding algo_vm}"
+              IsEnabled="{Binding IsEnabled, ElementName=modify_orders_button}"
+            >
+              <usp:OrderParamsPanel.CommandBindings>
+                <CommandBinding Command="{x:Static usp:OrderParamsPanel.SetPriceCommand}" Executed="{x:Static usp:OrderParamsPanel.SetPriceExecuted}"/>
+              </usp:OrderParamsPanel.CommandBindings>
+            </usp:OrderParamsPanel>
+          </GroupBox>
+          <GroupBox
+            x:Name="attachment_content_root"
+            Grid.Column="1"
+            Grid.Row="1"
+            Grid.RowSpan="2"
+            Padding="12"
+            BorderThickness="1"
+            HorizontalAlignment="Left"
+            Header="Attached Order Parameters"
+            HeaderTemplate="{StaticResource BoldHeaderTemplate}"
+            Margin="0,4,0,0"
+            Visibility="Collapsed"
+          >
+            <usp:OrderParamsPanel
+              x:Name="attached_order_params_panel"
+              DataContext="{Binding attach_vm}"
+              Price="{Binding price}"
+              Size="{Binding size_calculator.value}"
+              Accounts="{Binding accounts}"
+              SelectedAccount="{Binding selected_account}"
+              BestBidPrice="{Binding bbo.bid}"
+              BestBidSize="{Binding bbo.bid_size}"
+              BestAskPrice="{Binding bbo.ask}"
+              BestAskSize="{Binding bbo.ask_size}"
+              SizePresets="{Binding size_calculator.buttons}"
+              Security="{Binding security}"
+              AlgoVM="{Binding algo_vm}"
+              IsEnabled="{Binding IsEnabled, ElementName=send_attached_orders_button}"
+            >
+              <usp:OrderParamsPanel.CommandBindings>
+                <CommandBinding Command="{x:Static usp:OrderParamsPanel.SetPriceCommand}" Executed="{x:Static usp:OrderParamsPanel.SetPriceExecuted}"/>
+              </usp:OrderParamsPanel.CommandBindings>
+            </usp:OrderParamsPanel>
+          </GroupBox>
+        </Grid>
+        <Canvas Grid.Row="1" HorizontalAlignment="Left" Width="{Binding ActualWidth, ElementName=order_params_group_box}" Height="30">
+          <Button
+            x:Name="modify_orders_button"
+            Canvas.Top="{StaticResource DialogSkirtPadding.Top}"
+            Command="{Binding modify_selected_algos_command}"
+          >
+            <Canvas.Left>
+              <MultiBinding Converter="{x:Static sp:OrderBookView.RightPanelDialogSkirtLeftAnchorConverter}">
+                <Binding Path="Width" RelativeSource="{RelativeSource AncestorType=Canvas}"/>
+                <Binding Path="ActualWidth" RelativeSource="{RelativeSource Self}"/>
+              </MultiBinding>
+            </Canvas.Left>
+            <TextBlock>
+              <TextBlock.Style>
+                <Style TargetType="TextBlock">
+                  <Setter Property="Text" Value="{Binding selected_rows.Count, StringFormat='Modify Orders ({0})'}"/>
+                  <Style.Triggers>
+                    <DataTrigger Binding="{Binding IsEnabled, RelativeSource={RelativeSource AncestorType=Button}}" Value="False">
+                      <Setter Property="Text" Value="Modify Orders"/>
+                    </DataTrigger>
+                  </Style.Triggers>
+                </Style>
+              </TextBlock.Style>
+            </TextBlock>
+          </Button>
+        </Canvas>
+        <Canvas Grid.Row="1" HorizontalAlignment="Left" Width="{Binding ActualWidth, ElementName=attachment_content_root}" Height="30">
+          <StackPanel
+            x:Name="attach_orders_dialog_skirt"
+            Orientation="Horizontal"
+            Canvas.Top="{StaticResource DialogSkirtPadding.Top}"
+            Visibility="Collapsed"
+          >
+            <Canvas.Left>
+              <MultiBinding Converter="{x:Static sp:OrderBookView.RightPanelDialogSkirtLeftAnchorConverter}">
+                <Binding Path="Width" RelativeSource="{RelativeSource AncestorType=Canvas}"/>
+                <Binding Path="ActualWidth" RelativeSource="{RelativeSource Self}"/>
+              </MultiBinding>
+            </Canvas.Left>
+            <Button x:Name="send_attached_orders_button" Command="{Binding send_attached_orders_cmd}" Style="{StaticResource {x:Static c:DialogSkirt.DialogSkirtButtonStyleKey}}">
+              <TextBlock>
+                <TextBlock.Style>
+                  <Style TargetType="TextBlock">
+                    <Setter Property="Text" Value="{Binding selected_rows.Count, StringFormat='Attach To Orders ({0})'}"/>
+                    <Style.Triggers>
+                      <DataTrigger Binding="{Binding IsEnabled, RelativeSource={RelativeSource AncestorType=Button}}" Value="False">
+                        <Setter Property="Text" Value="Attach To Orders"/>
+                      </DataTrigger>
+                    </Style.Triggers>
+                  </Style>
+                </TextBlock.Style>
+              </TextBlock>
+            </Button>
+            <Button u:Behavior.CloseWindow="False" Margin="{StaticResource DialogSkirtButtonMargin}" Command="{Binding cancel_attach_orders_cmd}" Style="{StaticResource CancelButton}"/>
+          </StackPanel>
+        </Canvas>
+        
+      </Grid>
+      <StatusBar Grid.Row="1" DockPanel.Dock="Bottom">
+        <StatusBarItem HorizontalAlignment="Right">
+          <TextBlock>
+            <Run Text="Orders:"/>
+            <Run Text="{Binding rows.Count, Mode=OneWay}" />
+            <Run Text="of"/>
+            <Run Text="{Binding rows.total_row_count, Mode=OneWay}" />
+          </TextBlock>
+        </StatusBarItem>
+      </StatusBar>
+    </Grid>
+  </AdornerDecorator>
+</UserControl>
@@ -0,0 +1,151 @@
+//#define EXPAND_ATTACHMENT_PANEL
+using mbts.ui;
+using mbts.ui.converters;
+using mbts.ui.extensions;
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using System.Windows.Controls;
+using System.Windows.Data;
+using System.Windows.Input;
+
+namespace mbts.spark {
+   internal partial class OrderBookView : UserControl {
+      public const double
+         GridSplitterWidth = 5,
+         GridSplitterHeight = 5,
+         MinAlgoEditorHeight = 64,
+         MinAttachOrderParamsPanelWidth = 340,
+         AttachOrderParamsPanelWidthRatio = 0.33;
+
+      public static readonly IValueConverter
+         OrderDescriptionConverter = ValueConverter.create<OrderBookRowVM, string>(row => row == null ? string.Empty : row.order.short_description(row.security)),
+         FillsSlaveGridMaxHeightConverter = ValueConverter.create<double, double>(right_panel_height => right_panel_height - (GridSplitterHeight + MinAlgoEditorHeight)),
+         FillsPanelVisualStateConverter = ValueConverter.create<bool, string>(show => show ? VisualStateNames.FillsPanel.Active : VisualStateNames.FillsPanel.Inactive),
+         AttachmentTargetCursorConverter = ValueConverter.create<bool, Cursor>(is_active => is_active ? Cursors.Pen : Cursors.Arrow);
+
+      public static readonly IMultiValueConverter
+         RightPanelVisualStateConverter = ValueConverter.create<bool, bool, string>((is_modifying, is_attaching) =>
+            is_attaching ? VisualStateNames.RightPanel.AttachOrders :
+               (is_modifying ? VisualStateNames.RightPanel.ModifyOrders : VisualStateNames.RightPanel.Normal)),
+         RightPanelDialogSkirtLeftAnchorConverter = ValueConverter.create<double, double, double>((canvas_width, skirt_width) => canvas_width - skirt_width + GridSplitterWidth),
+         FillsSlaveGridStateConverter = ValueConverter.create<bool, bool, string>((is_fills_grid_visible, is_attaching) => is_fills_grid_visible && !is_attaching ? VisualStateNames.FillsPanel.Active : VisualStateNames.FillsPanel.Inactive);
+
+      public OrderBookView(OrderBookVM vm) {
+         InitializeComponent();
+         DataContext = vm;
+#if EXPAND_ATTACHMENT_PANEL
+         (RightPanelState right_panel, IDisposable hooks)? attach_op = null;
+         vm.begin_attaching += on_begin_attaching;
+         vm.end_attaching += on_end_attaching;
+         vm.SubscribeDisposed(() => {
+            if (attach_op.HasValue) {
+               vm.right_panel_width = attach_op.Value.right_panel.raw_width;
+               vm.fills_slave_grid_is_visible = attach_op.Value.right_panel.fills_slave_grid_is_visible;
+            }
+            vm.begin_attaching -= on_begin_attaching;
+            vm.end_attaching -= on_end_attaching;
+         });
+         const int delay_ms = 25;
+         async void on_begin_attaching() {
+            if (attach_op.HasValue) {
+               // begin-attaching is already underway (prob won't happen in practice as this event is triggered by user interaction)
+               return;
+            }
+            attach_op = (new RightPanelState(vm.right_panel_is_visible, vm.fills_slave_grid_is_visible, vm.raw_right_panel_width), orders_grid.SubscribePreviewMouseDown(cancel_on_grid_click));
+            vm.fills_slave_grid_is_visible = false;
+            vm.algo_editor_is_visible = true;
+            double target_width = Math.Max(ActualWidth * AttachOrderParamsPanelWidthRatio, MinAttachOrderParamsPanelWidth);
+            if (vm.right_panel_width < target_width) {
+               foreach (double incr in _get_incremental_widths(attach_op.Value.right_panel.is_visible ? attach_op.Value.right_panel.raw_width : 0, target_width)) {
+                  vm.right_panel_width = incr;
+                  await Task.Delay(delay_ms);
+                  if (!attach_op.HasValue)
+                     break;
+               }
+            }
+         }
+         async void on_end_attaching() {
+            if (!attach_op.HasValue) {
+               // end-attaching is already underway (prob won't happen in practice as this event is triggered by user interaction)
+               return;
+            }
+            attach_op.Value.hooks.Dispose();
+            var incr_widths = _get_incremental_widths(vm.right_panel_width, attach_op.Value.right_panel.raw_width);
+            vm.algo_editor_is_visible = attach_op.Value.right_panel.is_visible;
+            vm.fills_slave_grid_is_visible = attach_op.Value.right_panel.fills_slave_grid_is_visible;
+            vm.right_panel_width = attach_op.Value.right_panel.raw_width;
+            attach_op = null;
+            foreach (double incr in incr_widths) {
+               vm.right_panel_width = incr;
+               await Task.Delay(delay_ms);
+               if (attach_op.HasValue)
+                  break;
+            }
+         }
+#else
+         IDisposable attach_op = null;
+         vm.begin_attaching += on_begin_attaching;
+         vm.end_attaching += on_end_attaching;
+         void on_begin_attaching() => Disposable.replace(ref attach_op, orders_grid.SubscribePreviewMouseDown(cancel_on_grid_click));
+         void on_end_attaching() => Disposable.dispose(ref attach_op);
+#endif
+         void cancel_on_grid_click(object sender, MouseButtonEventArgs e) {
+            if (!KeyboardExtensions.IsCtrlDown() && !KeyboardExtensions.IsShiftDown())
+               vm.is_attaching_algos = false;
+         }
+      }
+
+      static IEnumerable<double> _get_incremental_widths(double from, double to) {
+         var list = new List<double> { to };
+         int incr = 1;
+         if (from < to) {
+            do {
+               list.Add(to - (incr * 0.6666));
+               list.Add(to - incr);
+               from += incr;
+               incr += incr;
+            } while (from < to);
+         } else if (from > to) {
+            do {
+               list.Add(to + incr);
+               incr += incr;
+               to += incr;
+            } while (from > to);
+         }
+         for (int i = list.Count - 1; i >= 0; i--) {
+            yield return list[i];
+         }
+      }
+
+      struct RightPanelState {
+         public readonly bool is_visible, fills_slave_grid_is_visible;
+         public readonly double raw_width;
+
+         public RightPanelState(bool right_panel_is_visible, bool fills_slave_grid_is_visible, double raw_right_panel_width) {
+            this.is_visible = right_panel_is_visible;
+            this.fills_slave_grid_is_visible = fills_slave_grid_is_visible;
+            this.raw_width = raw_right_panel_width;
+         }
+      }
+
+      public static class VisualStateNames {
+         public static class RightPanel {
+            public const string GroupName = nameof(RightPanel);
+
+            public static readonly string
+               Normal = $"{GroupName}{nameof(Normal)}",
+               ModifyOrders = $"{GroupName}{nameof(ModifyOrders)}",
+               AttachOrders = $"{GroupName}{nameof(AttachOrders)}";
+         }
+
+         public static class FillsPanel {
+            public const string GroupName = nameof(FillsPanel);
+
+            public static readonly string
+               Active = $"{GroupName}{VisualStates.Active}",
+               Inactive = $"{GroupName}{VisualStates.Inactive}";
+         }
+      }
+   }
+}
@@ -0,0 +1,143 @@
+<ResourceDictionary
+  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+  xmlns:order="clr-namespace:bts.api.orderman;assembly=spark_api"
+  xmlns:sp="clr-namespace:mbts.spark"
+  xmlns:u="clr-namespace:mbts.ui"
+  xmlns:c="clr-namespace:mbts.ui.controls"
+  xmlns:usp="clr-namespace:mbts.ui.spark"
+  xmlns:uspcv="clr-namespace:mbts.ui.spark.converters"
+  xmlns:sys="clr-namespace:System;assembly=mscorlib"
+>
+  <ControlTemplate x:Key="OrderParamsPanelTemplate" TargetType="usp:OrderParamsPanel">
+    <Grid Grid.IsSharedSizeScope="True">
+      <Grid.RowDefinitions>
+        <RowDefinition Height="Auto"/>
+        <RowDefinition Height="{Binding Source={StaticResource VerticalPush1}}"/>
+        <RowDefinition Height="Auto"/>
+        <RowDefinition Height="{Binding Source={StaticResource VerticalPush1}}"/>
+        <RowDefinition Height="*"/>
+      </Grid.RowDefinitions>
+      <Grid>
+        <Grid.ColumnDefinitions>
+          <ColumnDefinition Width="2*"/>
+          <ColumnDefinition Width="{Binding Source={StaticResource HorizontalPush1}}"/>
+          <ColumnDefinition Width="*"/>
+          <ColumnDefinition Width="{Binding Source={StaticResource HorizontalPush2}}"/>
+          <ColumnDefinition Width="*"/>
+        </Grid.ColumnDefinitions>
+        <usp:PriceEntryControl
+          ContractSpec="{Binding ContractSpec, RelativeSource={RelativeSource TemplatedParent}}"
+          Value="{Binding Price, RelativeSource={RelativeSource TemplatedParent}, Mode=TwoWay}"
+          ToolTip="Price"
+        />
+        <Button
+          x:Name="best_bid_button"
+          Grid.Column="2"
+          HorizontalAlignment="Stretch"
+          Command="{x:Static usp:OrderParamsPanel.SetPriceCommand}"
+          CommandParameter="{Binding BestBidPrice, RelativeSource={RelativeSource TemplatedParent}}"
+          Foreground="{u:BTSColor MarketData.bid}"
+          FontWeight="Bold"
+          Style="{DynamicResource {x:Static usp:OrderParamsPanel.BestBidPriceButtonStyleKey}}"
+        >
+          <MultiBinding Converter="{StaticResource TickDisplayConverter}">
+            <Binding Path="BestBidPrice" RelativeSource="{RelativeSource TemplatedParent}"/>
+            <Binding Path="ContractSpec" RelativeSource="{RelativeSource TemplatedParent}"/>
+          </MultiBinding>
+        </Button>
+        <Button
+          x:Name="best_ask_button"
+          Grid.Column="4"
+          HorizontalAlignment="Stretch"
+          Command="{x:Static usp:OrderParamsPanel.SetPriceCommand}"
+          CommandParameter="{Binding BestAskPrice, RelativeSource={RelativeSource TemplatedParent}}"
+          Foreground="{u:BTSColor MarketData.ask}"
+          FontWeight="Bold"
+          Style="{DynamicResource {x:Static usp:OrderParamsPanel.BestAskPriceButtonStyleKey}}"
+        >
+          <MultiBinding Converter="{StaticResource TickDisplayConverter}">
+            <Binding Path="BestAskPrice" RelativeSource="{RelativeSource TemplatedParent}"/>
+            <Binding Path="ContractSpec" RelativeSource="{RelativeSource TemplatedParent}"/>
+          </MultiBinding>
+        </Button>
+      </Grid>
+      <Grid Grid.Row="2">
+        <Grid.ColumnDefinitions>
+          <ColumnDefinition Width="2*"/>
+          <ColumnDefinition Width="{Binding Source={StaticResource HorizontalPush1}}"/>
+          <ColumnDefinition Width="*"/>
+          <ColumnDefinition Width="{Binding Source={StaticResource HorizontalPush2}}"/>
+          <ColumnDefinition Width="*"/>
+        </Grid.ColumnDefinitions>
+        <Grid.RowDefinitions>
+          <RowDefinition Height="Auto"/>
+          <RowDefinition Height="{Binding Source={StaticResource VerticalPush1}}"/>
+          <RowDefinition Height="*"/>
+          <RowDefinition Height="*"/>
+        </Grid.RowDefinitions>
+        <c:TickUpDownNullableUInt Value="{Binding Size, RelativeSource={RelativeSource TemplatedParent}}" ToolTip="Size"/>
+        <Button
+          x:Name="best_bid_size_button"
+          Grid.Column="2"
+          HorizontalAlignment="Stretch"
+          Content="{Binding BestBidSize, RelativeSource={RelativeSource TemplatedParent}}"
+          Foreground="{u:BTSColor MarketData.bid}"
+          Style="{DynamicResource {x:Static usp:OrderParamsPanel.BestBidSizeButtonStyleKey}}"
+        />
+        <Button
+          x:Name="best_ask_size_button"
+          Grid.Column="4"
+          HorizontalAlignment="Stretch"
+          Content="{Binding BestAskSize, RelativeSource={RelativeSource TemplatedParent}}"
+          Foreground="{u:BTSColor MarketData.ask}"
+          Style="{DynamicResource {x:Static usp:OrderParamsPanel.BestAskSizeButtonStyleKey}}"
+        />
+        <ItemsControl Grid.Row="2" Grid.RowSpan="2" Margin="-2,-2,-2,0" ItemsSource="{Binding SizePresets, RelativeSource={RelativeSource TemplatedParent}}" Focusable="False">
+          <ItemsControl.ItemsPanel>
+            <ItemsPanelTemplate>
+              <UniformGrid Columns="3" Focusable="False"/>
+            </ItemsPanelTemplate>
+          </ItemsControl.ItemsPanel>
+          <ItemsControl.ItemTemplate>
+            <DataTemplate>
+              <Button
+                HorizontalAlignment="Stretch"
+                Margin="2,4,2,0"
+                Content="{Binding}"
+                Focusable="False"
+                Style="{DynamicResource {x:Static usp:OrderParamsPanel.SizeCalculatorButtonStyleKey}}"
+              />
+            </DataTemplate>
+          </ItemsControl.ItemTemplate>
+        </ItemsControl>
+        <Grid Grid.Row="2" Grid.RowSpan="2" Grid.Column="2" Grid.ColumnSpan="3">
+          <Grid.RowDefinitions>
+            <RowDefinition/>
+            <RowDefinition/>
+          </Grid.RowDefinitions>
+          <ComboBox Margin="0,2,0,4" ItemsSource="{Binding Accounts, RelativeSource={RelativeSource TemplatedParent}}" SelectedItem="{Binding SelectedAccount, RelativeSource={RelativeSource TemplatedParent}}" ToolTip="Choose Account"/>
+          <ComboBox Grid.Row="1">
+            <ComboBox.Style>
+              <Style TargetType="ComboBox" BasedOn="{StaticResource DisabledPlaceholderComboBox}">
+                <Setter Property="ItemsSource">
+                  <Setter.Value>
+                    <x:ArrayExtension Type="{x:Type sys:String}">
+                      <sys:String>Time In Force (N/A)</sys:String>
+                    </x:ArrayExtension>
+                  </Setter.Value>
+                </Setter>
+              </Style>
+            </ComboBox.Style>
+          </ComboBox>
+        </Grid>
+      </Grid>
+      <usp:AlgoEditorView x:Name="algo_editor" Grid.Row="4" DataContext="{Binding AlgoVM, RelativeSource={RelativeSource TemplatedParent}}"/>
+    </Grid>
+  </ControlTemplate>
+
+  <Style TargetType="usp:OrderParamsPanel">
+    <Setter Property="MinWidth" Value="300"/>
+    <Setter Property="Template" Value="{StaticResource OrderParamsPanelTemplate}"/>
+  </Style>
+</ResourceDictionary>
@@ -0,0 +1,188 @@
+using bts.api;
+using mbts.spark;
+using System;
+using System.Collections;
+using System.Linq;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Input;
+
+namespace mbts.ui.spark {
+   class OrderParamsPanel : Control {
+      public const string
+         BestBidPriceButtonStyleKey = nameof(BestBidPriceButtonStyleKey),
+         BestBidSizeButtonStyleKey = nameof(BestBidSizeButtonStyleKey),
+         BestAskPriceButtonStyleKey = nameof(BestAskPriceButtonStyleKey),
+         BestAskSizeButtonStyleKey = nameof(BestAskSizeButtonStyleKey),
+         SizeCalculatorButtonStyleKey = nameof(SizeCalculatorButtonStyleKey);
+
+      public static readonly RoutedCommand SetPriceCommand = new RoutedCommand();
+
+      public static readonly ExecutedRoutedEventHandler SetPriceExecuted =
+         (s, e) => {
+            if (s is OrderParamsPanel opp)
+               opp.SetCurrentValue(PriceProperty, ConvertUtils.try_convert(e.Parameter, out double d) ? d : double.NaN);
+         };
+
+      public static readonly CanExecuteRoutedEventHandler
+         SetPriceCanExecute = (s, e) => e.CanExecute = e.Parameter is double,
+         SetSizeCanExecute = (s, e) => e.CanExecute = e.Parameter is uint;
+
+      static OrderParamsPanel() {
+         DefaultStyleKeyProperty.OverrideMetadata(typeof(OrderParamsPanel), new FrameworkPropertyMetadata(typeof(OrderParamsPanel)));
+      }
+
+      #region Price
+      public static readonly DependencyProperty PriceProperty =
+         WPFHelper.create_dp<double, OrderParamsPanel>(nameof(Price), FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, double.NaN);
+
+      public double Price {
+         get => (double)GetValue(PriceProperty);
+         set => SetValue(PriceProperty, value);
+      }
+      #endregion
+
+      #region Size
+      public static readonly DependencyProperty SizeProperty =
+         WPFHelper.create_dp<uint?, OrderParamsPanel>(nameof(Size), FrameworkPropertyMetadataOptions.BindsTwoWayByDefault);
+
+      public uint? Size {
+         get => GetValue(SizeProperty) as uint?;
+         set => SetValue(SizeProperty, value);
+      }
+      #endregion
+
+      #region SizePresets
+      public static readonly DependencyProperty SizePresetsProperty =
+         WPFHelper.create_dp<IEnumerable, OrderParamsPanel>(nameof(SizePresets), Enumerable.Empty<string>());
+
+      public IEnumerable SizePresets {
+         get => GetValue(SizePresetsProperty) as IEnumerable;
+         set => SetValue(SizePresetsProperty, value);
+      }
+      #endregion
+
+      #region BestBidPrice
+      public static readonly DependencyProperty BestBidPriceProperty =
+         WPFHelper.create_dp<double?, OrderParamsPanel>(nameof(BestBidPrice));
+
+      public double? BestBidPrice {
+         get => GetValue(BestBidPriceProperty) as double?;
+         set => SetValue(BestBidPriceProperty, value);
+      }
+      #endregion
+
+      #region BestBidSize
+      public static readonly DependencyProperty BestBidSizeProperty =
+         WPFHelper.create_dp<uint?, OrderParamsPanel>(nameof(BestBidSize));
+
+      public uint? BestBidSize {
+         get => GetValue(BestBidSizeProperty) as uint?;
+         set => SetValue(BestBidSizeProperty, value);
+      }
+      #endregion
+
+      #region BestAskPrice
+      public static readonly DependencyProperty BestAskPriceProperty =
+         WPFHelper.create_dp<double?, OrderParamsPanel>(nameof(BestAskPrice));
+
+      public double? BestAskPrice {
+         get => GetValue(BestAskPriceProperty) as double?;
+         set => SetValue(BestAskPriceProperty, value);
+      }
+      #endregion
+
+      #region BestAskSize
+      public static readonly DependencyProperty BestAskSizeProperty =
+         WPFHelper.create_dp<uint?, OrderParamsPanel>(nameof(BestAskSize));
+
+      public uint? BestAskSize {
+         get => GetValue(BestAskSizeProperty) as uint?;
+         set => SetValue(BestAskSizeProperty, value);
+      }
+      #endregion
+
+      #region Accounts
+      public static readonly DependencyProperty AccountsProperty =
+         WPFHelper.create_dp<IEnumerable, OrderParamsPanel>(nameof(Accounts), Enumerable.Empty<string>());
+
+      public IEnumerable Accounts {
+         get => GetValue(AccountsProperty) as IEnumerable;
+         set => SetValue(AccountsProperty, value);
+      }
+      #endregion
+
+      #region SelectedAccount
+      public static readonly DependencyProperty SelectedAccountProperty =
+         WPFHelper.create_dp<object, OrderParamsPanel>(nameof(SelectedAccount));
+
+      public object SelectedAccount {
+         get => GetValue(SelectedAccountProperty);
+         set => SetValue(SelectedAccountProperty, value);
+      }
+      #endregion
+
+      #region TimeInForces
+      public static readonly DependencyProperty TimeInForcesProperty =
+         WPFHelper.create_dp<IEnumerable, OrderParamsPanel>(nameof(TimeInForces), Enumerable.Empty<string>());
+
+      public IEnumerable TimeInForces {
+         get => GetValue(TimeInForcesProperty) as IEnumerable;
+         set => SetValue(TimeInForcesProperty, value);
+      }
+      #endregion
+
+      #region SelectedTimeInForce
+      public static readonly DependencyProperty SelectedTimeInForceProperty =
+         WPFHelper.create_dp<object, OrderParamsPanel>(nameof(SelectedTimeInForce));
+
+      public object SelectedTimeInForce {
+         get => GetValue(SelectedTimeInForceProperty);
+         set => SetValue(SelectedTimeInForceProperty, value);
+      }
+      #endregion
+
+      #region Security
+      public static readonly DependencyProperty SecurityProperty =
+         WPFHelper.create_dp<SecurityImmutable?, OrderParamsPanel>(
+            nameof(Security),
+            (o, v) => o.CoerceValue(ContractSpecProperty));
+
+      public SecurityImmutable? Security {
+         get => GetValue(SecurityProperty) as SecurityImmutable?;
+         set => SetValue(SecurityProperty, value);
+      }
+      #endregion
+
+      #region ContractSpec
+      public static readonly DependencyProperty ContractSpecProperty =
+         WPFHelper.create_dp<ContractSpecificationImmutable?, OrderParamsPanel>(
+            nameof(ContractSpec),
+            null,
+            (d, base_value) => d.Security?.ContractSpec ?? base_value ?? SecurityDataHelper.Defaults.ContractSpecificationImmutable);
+
+      public ContractSpecificationImmutable? ContractSpec {
+         get => GetValue(ContractSpecProperty) as ContractSpecificationImmutable?;
+         set => SetValue(ContractSpecProperty, value);
+      }
+      #endregion
+
+      #region AlgoVM
+      public static readonly DependencyProperty AlgoVMProperty =
+         WPFHelper.create_dp<AlgoDefinitionVM, OrderParamsPanel>(
+            nameof(AlgoVM),
+            (o, v) => o._algo_editor?.SetCurrentValue(VisibilityProperty, v != null ? Visibility.Visible : Visibility.Collapsed));
+
+      public AlgoDefinitionVM AlgoVM {
+         get => GetValue(AlgoVMProperty) as AlgoDefinitionVM;
+         set => SetValue(AlgoVMProperty, value);
+      }
+      #endregion
+
+      AlgoEditorView _algo_editor;
+      public override void OnApplyTemplate() {
+         _algo_editor = GetTemplateChild("algo_editor") as AlgoEditorView;
+         _algo_editor?.SetCurrentValue(VisibilityProperty, AlgoVM != null ? Visibility.Visible : Visibility.Collapsed);
+      }
+   }
+}
@@ -84,17 +84,17 @@ namespace bts.shell {
         static class DefaultColumns {

            public static GridColumnSettings account => new GridColumnSettings(col_id(Columns.Account), DefaultColumnHeaders.Account, width: DefaultColumnWidths.Account);
-            public static GridColumnSettings exchange => new GridColumnSettings(col_id(Columns.Exchange), DefaultColumnHeaders.Exchange, width: DefaultColumnWidths.Exchange);
+            public static GridColumnSettings exchange => new GridColumnSettings(col_id(Columns.Exchange), DefaultColumnHeaders.Exchange, false, width: DefaultColumnWidths.Exchange);
            public static GridColumnSettings symbol => new GridColumnSettings(col_id(Columns.Symbol), DefaultColumnHeaders.Symbol, width: DefaultColumnWidths.Symbol);
            public static GridColumnSettings security => new GridColumnSettings(col_id(Columns.Security), DefaultColumnHeaders.Security, width: DefaultColumnWidths.Security);
            public static GridColumnSettings security_type => new GridColumnSettings(col_id(Columns.SecurityType), DefaultColumnHeaders.SecurityType, width: DefaultColumnWidths.SecurityType);
            public static GridColumnSettings start_net_position => new GridColumnSettings(col_id(Columns.StartNetPos), DefaultColumnHeaders.StartNetPos, width: DefaultColumnWidths.Start_Net_Pos, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
-            public static GridColumnSettings start_pnl => new GridColumnSettings(col_id(Columns.StartPNL), DefaultColumnHeaders.StartPnL, width: DefaultColumnWidths.PnL_Generic, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
+            public static GridColumnSettings start_pnl => new GridColumnSettings(col_id(Columns.StartPNL), DefaultColumnHeaders.StartPnL, false, width: DefaultColumnWidths.PnL_Generic, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
            public static GridColumnSettings day_long_pnl => new GridColumnSettings(col_id(Columns.DayLong), DefaultColumnHeaders.DayLong, width: DefaultColumnWidths.PnL_Generic, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
            public static GridColumnSettings day_short_pnl => new GridColumnSettings(col_id(Columns.DayShort), DefaultColumnHeaders.DayShort, width: DefaultColumnWidths.PnL_Generic, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
            public static GridColumnSettings day_pnl => new GridColumnSettings(col_id(Columns.DayPNL), DefaultColumnHeaders.DayPnL, width: DefaultColumnWidths.PnL_Generic, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
-            public static GridColumnSettings total_net_pos => new GridColumnSettings(col_id(Columns.TotalNetPos), DefaultColumnHeaders.TotalNetPos, width: DefaultColumnWidths.Total_Net_Pos, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
-            public static GridColumnSettings total_pnl => new GridColumnSettings(col_id(Columns.TotalPNL), DefaultColumnHeaders.TotalPnL, width: DefaultColumnWidths.PnL_Generic, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
+            public static GridColumnSettings total_net_pos => new GridColumnSettings(col_id(Columns.TotalNetPos), DefaultColumnHeaders.TotalNetPos, false, width: DefaultColumnWidths.Total_Net_Pos, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
+            public static GridColumnSettings total_pnl => new GridColumnSettings(col_id(Columns.TotalPNL), DefaultColumnHeaders.TotalPnL, false, width: DefaultColumnWidths.PnL_Generic, horizontal_alignment: System.Windows.HorizontalAlignment.Right);
            public static GridColumnSettings pnl_price => new GridColumnSettings(col_id(Columns.PNLPrice), DefaultColumnHeaders.PnLPrice, width: DefaultColumnWidths.PnL_Generic, horizontal_alignment: System.Windows.HorizontalAlignment.Right);

            public static IEnumerable<SortingCriteria> default_sorting_criterion {
@@ -158,6 +158,8 @@ namespace bts.shell {
         // ProtoMember 13 cannot be used further
         [ProtoMember(14)]
         public SecurityType[] security_types;
+         [ProtoMember(15)]
+         public bool[] has_day_trades;
      }

   }
@@ -12,7 +12,6 @@ using System.Collections.Generic;
 using System.ComponentModel.Composition;
 using System.Linq;
 using System.Reactive.Linq;
-using OrderTuple = System.ValueTuple<bts.api.SecurityImmutable?, bts.api.orderman.OrderRecordImmutable>;

 namespace bts.shell {
   interface INotificationService {
@@ -20,40 +19,14 @@ namespace bts.shell {
      INotificationServiceDataCache data_cache { get; }
      IDisposable link_to_activity(IPredicate<Activity> predicate, SoundNotification sound);
      IDisposable link_to_activity(INotificationPredicate<Activity> toast_notification_predicate);
-      IDisposable link_to_order(IPredicate<OrderTuple> predicate, SoundNotification sound);
-      IDisposable link_to_order(INotificationPredicate<OrderTuple> toast_notification_predicate);
-   }
-
-   static class NotificationServiceExtensions {
-      /// TODO: remove this extension and force callers to use the appropriate 'link' method in <see cref="INotificationService"/> (it is smelly, and is NOT ACTUALLY STRONGLY TYPED)
-      public static IDisposable link<T>(this INotificationService notification_service, IPredicate<T> predicate, SoundNotification sound) {
-         if (predicate is IPredicate<OrderTuple> orp)
-            return notification_service.link_to_order(orp, sound);
-         if (predicate is IPredicate<OrderSecurity> osp) {
-            // Note: watch out for implicit types as generic type arguments (although OrderSecurity can be implicitly cast to OrderTuple, IPredicate<OrderSecurity> CANNOT be implicitly cast to IPredicate<OrderTuple>)
-            return notification_service.link_to_order(PredicateBuilder.create<OrderTuple>(ot => osp.trigger(new OrderSecurity(ot.Item1, ot.Item2))), sound);
-         }
-         if (predicate is IPredicate<Activity> ap)
-            return notification_service.link_to_activity(ap, sound);
-         Log.Ui.error($"Unable to activate sound-trigger (unrecognized predicate type '{typeof(T)}').");
-         return Disposable.empty;
-      }
-
-      /// TODO: remove this extension and force callers to use the appropriate 'link' method in <see cref="INotificationService"/> (it is smelly, and is NOT ACTUALLY STRONGLY TYPED)
-      public static IDisposable link<T>(this INotificationService notification_service, INotificationPredicate<T> toast_notification_predicate) {
-         if (toast_notification_predicate is INotificationPredicate<OrderTuple> orp)
-            return notification_service.link_to_order(orp);
-         if (toast_notification_predicate is INotificationPredicate<Activity> ap)
-            return notification_service.link_to_activity(ap);
-         Log.Ui.error($"Unable to activate toast-notification-trigger (unrecognized predicate type '{typeof(T)}').");
-         return Disposable.empty;
-      }
+      IDisposable link_to_order(IPredicate<OrderSecurity> predicate, SoundNotification sound);
+      IDisposable link_to_order(INotificationPredicate<OrderSecurity> toast_notification_predicate);
   }

   [Export(typeof(INotificationService))]
   partial class NotificationService : INotificationService, IDisposable {
      readonly NotificationProcessor<Activity> _activity_notifications;
-      readonly NotificationProcessor<OrderTuple> _order_notifications;
+      readonly NotificationProcessor<OrderSecurity> _order_notifications;
      readonly DataCache _data_cache = new DataCache();

      IDisposable _dispose;
@@ -62,7 +35,7 @@ namespace bts.shell {
      public NotificationService(IBus bus, INotifier notifier, OrdersModel orders_model) {
         this.notifier = notifier;
         _activity_notifications = new NotificationProcessor<Activity>(notifier);
-         _order_notifications = new NotificationProcessor<OrderTuple>(notifier);
+         _order_notifications = new NotificationProcessor<OrderSecurity>(notifier);
         _dispose = Disposable.Create(
            bus.subscribe(SparkTags.LogActivity).Subscribe(_on_activity),
            orders_model.on_orders.Subscribe(_on_orders)
@@ -75,8 +48,8 @@ namespace bts.shell {

      public IDisposable link_to_activity(IPredicate<Activity> predicate, SoundNotification sound) => _activity_notifications.link(predicate, sound);
      public IDisposable link_to_activity(INotificationPredicate<Activity> toast_notification_predicate) => _activity_notifications.link(toast_notification_predicate);
-      public IDisposable link_to_order(IPredicate<OrderTuple> predicate, SoundNotification sound) => _order_notifications.link(predicate, sound);
-      public IDisposable link_to_order(INotificationPredicate<OrderTuple> toast_notification_predicate) => _order_notifications.link(toast_notification_predicate);
+      public IDisposable link_to_order(IPredicate<OrderSecurity> predicate, SoundNotification sound) => _order_notifications.link(predicate, sound);
+      public IDisposable link_to_order(INotificationPredicate<OrderSecurity> toast_notification_predicate) => _order_notifications.link(toast_notification_predicate);
      public void Dispose() => Disposable.dispose(ref _dispose);

      void _on_activity(Activity activity) =>
@@ -79,10 +79,12 @@ namespace mbts.spark {
               RequestClose?.Invoke(this, new EventArgs());
            }
         });
+         bbo = new BBOVM();
         _dispose = Disposable.Create(
            size_calculator,
            properties_vm,
-            bbo = new BBOVM(security_md_source),
+            security_md_source.OnDispatcher().Subscribe(smd => bbo.security_md = smd),
+            bbo,
            order_source.OnDispatcher().Subscribe(ort => {
               key = ort.order.Key;
               if (DoubleHelper.IsNaNOrInfinity(price))
@@ -49,7 +49,7 @@ namespace mbts.spark {
      ) {
         _security = backing(nameof(security), security_md_source.Select(smd => smd.security), SecurityDataHelper.Defaults.SecurityImmutable);
         properties_vm = new OrderPropertiesEditorVM(model, security_md_source, props_source.Select(p => p.order_props));
-         bbo = new BBOVM(security_md_source);
+         bbo = new BBOVM();
         send_order = new DelegateCommand<Side>(side => {
            bool price_valid = _validate_price(), size_valid = size_calculator.validate();
            if (price_valid && size_valid && !HasErrors && !properties_vm.HasErrors) {
@@ -59,6 +59,8 @@ namespace mbts.spark {
         });
         set_price_command = new DelegateCommand<double>(set_price);
         _dispose = Disposable.Create(
+            bbo,
+            security_md_source.OnDispatcher().Subscribe(smd => bbo.security_md = smd),
            size_calculator = new CalculatorLogic(0, calculator_buttons),
            props_source.OnDispatcher().Subscribe(p => on_props(p.price, p.size))
         );
@@ -2,6 +2,7 @@
 using bts.api.core;
 using bts.api.orderman;
 using bts.shell;
+using bts.utils;
 using mbts;
 using mbts.spark;
 using mbts.ui.controls;
@@ -83,25 +84,18 @@ namespace bts.spark {
      public static string modified_description(OrderRecordImmutable old_order, OrderRecordImmutable new_order, ContractSpecificationImmutable? spec) {
         double old_price = old_order.State.Price, new_price = new_order.State.Price;
         uint old_size = old_order.State.Quantity, new_size = new_order.State.Quantity;
-         string modified_size_partial_description(int working_size) {
-            return $"size from {old_size} to {new_size}, working {working_size}";
+         uint old_attached_target_key = old_order.attached_target_order_key(), new_attached_target_key = new_order.attached_target_order_key();
+         return StringBuilderEx.join(prefix, change_descs());
+         //
+         string prefix() => $"({old_order.Key}) Changed";
+         IEnumerable<string> change_descs() {
+            if (old_price != new_price)
+               yield return $"price from {spec.format(old_price)} to {spec.format(new_price)}";
+            if (old_size != new_size)
+               yield return $"size from {old_size} to {new_size}, working {new_order.working_quantity()}";
+            if (old_attached_target_key != new_attached_target_key)
+               yield return $"attached target from {old_attached_target_key} to {new_attached_target_key}";
         }
-         string modified_price_partial_description() {
-            return $"price from {spec.format(old_price)} to {spec.format(new_price)}";
-         }
-         if (old_price != new_price || old_size != new_size) {
-            StringBuilder sb = new StringBuilder($"({old_order.Key}) Changed ");
-            if (old_price != new_price) {
-               sb.Append(modified_price_partial_description());
-               if (old_size != new_size)
-                  sb.Append($", {modified_size_partial_description(new_order.working_quantity())}");
-            }
-            else
-               sb.Append(modified_size_partial_description(new_order.working_quantity()));
-            return sb.ToString();
-         }
-         else
-            return string.Empty;
      }

      static string _header(uint key) => $"({key})";
@@ -184,21 +178,31 @@ namespace bts.spark {
            format_cancel_error(order, security?.ContractSpec, error));
      }

-      internal void update_order(OrderRecordImmutable order, double price, uint size) {
+      internal void update_order(OrderRecordImmutable order, double price, uint size, bool algo_changed) =>
+         _log_order_update(order, price, size, algo_changed, "change from");
+
+      internal void update_order_failed(OrderRecordImmutable order, double price, uint size, bool algo_changed) =>
+         _log_order_update(order, price, size, algo_changed, "failed to change from");
+
+      void _log_order_update(OrderRecordImmutable order, double price, uint size, bool algo_changed, string change_desc_prefix) {
+         if (price == order.price() && size == order.working_quantity() && !algo_changed) {
+            // nothing actually changed
+            return;
+         }
+         const string algo_change_text = "change algo parameters";
         var security = try_get_security(order.Def.SecurityKey);
         var spec = security?.ContractSpec;
-         log_status(ActivityLogCategory.modify,
-            security,
-            $"({order.Key}) change from {order.State.Quantity}@{spec.format(order.State.Price)} to {size}@{spec.format(price)}");
+         var desc_builder = new StringBuilderEx();
+         if (price != order.price() || size != order.working_quantity()) {
+            desc_builder.Add(order.State.Quantity.ToString(), "@", spec.format(order.State.Price), "to ", size.ToString(), "@", spec.format(price));
+            if (algo_changed)
+               desc_builder.Add("; ", algo_change_text);
+         } else if (algo_changed) {
+            desc_builder.Add(algo_change_text);
+         }
+         desc_builder.Insert(0, $"{change_desc_prefix} ");
+         desc_builder.Insert(0, $"({order.Key}) ");
+         log_status(ActivityLogCategory.modify, security, desc_builder.ToString());
      }
-
-      internal void update_order_failed(OrderRecordImmutable order, double price, uint size) {
-         var security = try_get_security(order.Def.SecurityKey);
-         var spec = security?.ContractSpec;
-         log_status(ActivityLogCategory.modify,
-            security,
-            $"({order.Key}) failed to change from {order.State.Quantity}@{spec.format(order.State.Price)} to {size}@{spec.format(price)}");
-      }
-
   }
 }
@@ -346,9 +346,9 @@ namespace mbts.spark {
         _time_in_force.observe_current(start_immediately);

      public IObservable<IAlgoVM> observe_order_type(bool start_immediately = false) =>
-          _model.algo_model.templates_enabled() ?
-             _selected_algo_template.observe_current(start_immediately).Select(t => t?.algo_root) :
-             _selected_algo_definition.observe_selected_item(start_immediately).Select(d => d?.algo_root);
+         _model.algo_model.templates_enabled() ?
+            _selected_algo_template.observe_current(start_immediately).Select(t => t?.algo_root) :
+            _selected_algo_definition.observe_selected_item(start_immediately).Select(d => d?.algo_root);

      public OrderDefinition create(Side side) {
         if (HasErrors)
@@ -11,7 +11,7 @@ using AlgoDefi = bts.api.orderman.CustomOrderDefinitionImmutable;
 using AlgoType = bts.api.orderman.CustomOrderDefinition.CustomOneofCase;

 namespace mbts.spark {
-   class DefaultAlgoVM : DisposableViewModelBase, IAlgoVM, IDynamicAlgoVMImpl, IObserver<SecurityMD?>, IObserver<OrdersModel> {
+   class DefaultAlgoVM : DisposableViewModelBase, IAlgoVM, IDynamicAlgoVMImpl, IObserver<SecurityMD?>, IObserver<OrdersModel>, IObserver<AlgoEditingPermissions> {
      static readonly AlgoDefi _empty = new AlgoDefi(new AlgoDef());
      readonly VersionContainer<AlgoDefi> _definition;
      AlgoFormats _format;
@@ -37,21 +37,15 @@ namespace mbts.spark {
               impl.is_expanded = value;
         }
      }
-      public bool can_edit_values => impl?.can_edit_values ?? false;
-      public bool can_edit_structure => impl?.can_edit_structure ?? false;
-      public bool can_save_values => impl?.can_save_values ?? false;
-      public bool can_save_structure => impl?.can_save_structure ?? false;
+      public AlgoEditingPermissions editing_permissions => _editing_permissions;
      public string display_name => impl?.display_name ?? "(Default)";
      public AlgoDefi definition => _definition.value;
      public ObservableCollection<IAlgoSelector> child_algo_selectors { get; } = new ObservableCollection<IAlgoSelector>();
+      public dynamic children_vm => impl?.children_vm;

      public void assign_to(AlgoDef value) => value.MergeFrom(definition.CloneToMutable());
      public bool key_match(KeyEventArgs e) => false;
      public void load_from(AlgoDefi value) => impl?.load_from(value);
-      public void set_permissions(AlgoEditingPermissions editing_permissions) {
-         _editing_permissions = editing_permissions;
-         impl?.set_permissions(editing_permissions);
-      }
      public Task<AlgoDefi?> load_from_async(AlgoDefi definition) =>
         impl?.load_from_async(definition) ?? Task.FromResult<AlgoDefi?>(definition);

@@ -98,6 +92,13 @@ namespace mbts.spark {
         _on_impl_definition_changed();
      }

+      void IObserver<AlgoEditingPermissions>.OnCompleted() { }
+      void IObserver<AlgoEditingPermissions>.OnError(Exception error) { }
+      void IObserver<AlgoEditingPermissions>.OnNext(AlgoEditingPermissions editing_permissions) {
+         Set(ref _editing_permissions, editing_permissions, nameof(this.editing_permissions));
+         (impl as IObserver<AlgoEditingPermissions>)?.OnNext(editing_permissions);
+      }
+
      void _on_impl_definition_changed() {
         var orig_def = definition;
         _definition.increment_version();
@@ -105,6 +106,7 @@ namespace mbts.spark {
            definition_changed?.Invoke();
         if (order_type != orig_def.CustomCase)
            RaisePropertyChanged(nameof(order_type), nameof(meta));
+         RaisePropertyChanged(nameof(children_vm));
      }
   }
-}
+}
@@ -2,6 +2,7 @@ using bts.api;
 using bts.api.orderman;
 using bts.utils;
 using Google.Protobuf.Reflection;
+using mbts.ui.utility;
 using mbts.utils;
 using System;
 using System.Collections.Generic;
@@ -11,8 +12,9 @@ using System.Reactive.Linq;

 namespace mbts.spark {
   [Export]   
-   public class DynamicOrderHelper
-   {
+   class DynamicOrderHelper {
+      public readonly IMaskIndexInt32<string> dynamic_type_index;
+
      static readonly IReadOnlyDictionary<DynamicOrderParam.ValueOneofCase, (FieldDescriptor field_descriptor, Type field_type)> _descriptor_case_index =
         ProtoHelper.get_oneof_descriptor_index<DynamicOrderParam, DynamicOrderParam.ValueOneofCase>(nameof(DynamicOrderParam.ValueCase));

@@ -21,6 +23,7 @@ namespace mbts.spark {
      private DynamicOrderHelper(OrderService order_service)
      {
         _dynamic_types = order_service.get_registered_dynamic_order_types(new VoidMessage());
+         dynamic_type_index = new MaskIndexInt32<string>(_dynamic_types.DynamicOrderDesc.Select(d => d.DynamicOrderType).ToList());
      }

      public void add_dynamic_order_defs(List<CustomOrderDefinitionImmutable> defs,
@@ -30,9 +33,9 @@ namespace mbts.spark {
         {
            var dorder = factory(CustomOrderDefinition.CustomOneofCase.Dynamic);
            dorder.Dynamic.DynamicOrderType = d.DynamicOrderType;
+            var ddef = dorder.Dynamic;
            //Add only the descriptor here for reflection later
-            foreach(var p in d.ParamDesc)
-               dorder.Dynamic.OrderParams.Add( p.ParamName, new DynamicOrderParam() );
+            add_dynamic_params(ref ddef);
            defs.Add(new CustomOrderDefinitionImmutable(dorder));
         }
      }
@@ -42,39 +45,35 @@ namespace mbts.spark {

      internal DynamicOrderDefinition create_def(string dynamic_type) {
         var desc = get_descriptor(dynamic_type);
-         var def = new DynamicOrderDefinition();
-         foreach (var p in desc.ParamDesc) {
-            if (_is_child_algo_desc(p)) {
-               def.OrderParams[p.ParamName] = new DynamicOrderParam { AsOrderDef = new CustomOrderDefinition() };
-            } else if (_is_value_param_desc(p)) {
-               var value_case = _get_value_case(p.ParamType.Primitive);
-               if (_descriptor_case_index.TryGetValue(value_case, out (FieldDescriptor fd, Type type) tup)) {
-                  var dop = new DynamicOrderParam();
-                  tup.fd.Accessor.SetValue(dop, ConvertUtils.get_default(tup.type));
-                  def.OrderParams[p.ParamName] = dop;
-               }
-            }
-         }
+         var def = new DynamicOrderDefinition { DynamicOrderType = dynamic_type };
+         add_dynamic_params(ref def);
         return def;
      }

-      static DynamicOrderParam.ValueOneofCase _get_value_case(DynamicOrderPrimitiveDescriptor primitive_descriptor_case) {
-         switch (primitive_descriptor_case) {
-            case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveBool: return DynamicOrderParam.ValueOneofCase.AsBool;
-            case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveDouble: return DynamicOrderParam.ValueOneofCase.AsBool;
-            case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveInt: return DynamicOrderParam.ValueOneofCase.AsInt32;
-            case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveUint: return DynamicOrderParam.ValueOneofCase.AsUint32;
-            case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveString: return DynamicOrderParam.ValueOneofCase.AsString;
-            default: throw ExceptionBuilder.Argument.unexpected_case(primitive_descriptor_case, nameof(primitive_descriptor_case));
-         }
+      internal void add_dynamic_params(ref DynamicOrderDefinition dynamic_def) {
+         var desc = get_descriptor(dynamic_def.DynamicOrderType);
+         foreach (var p in desc.ParamDesc)
+            dynamic_def.OrderParams[p.ParamName] = init_param(p);
      }

-      static bool _is_child_algo_desc(DynamicOrderParamDescriptor desc) =>
-           desc.ParamType.DescriptorCase == DynamicOrderTypeDescriptor.DescriptorOneofCase.Primitive &&
-           desc.ParamType.Primitive == DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveOrderDef;
-
-      static bool _is_value_param_desc(DynamicOrderParamDescriptor desc) =>
-         desc.ParamType.DescriptorCase == DynamicOrderTypeDescriptor.DescriptorOneofCase.Enumerated ||
-         (desc.ParamType.DescriptorCase == DynamicOrderTypeDescriptor.DescriptorOneofCase.Primitive && desc.ParamType.Primitive != DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveOrderDef);
+      internal static DynamicOrderParam init_param(DynamicOrderParamDescriptor descriptor) {
+         var param = new DynamicOrderParam();
+         switch (descriptor.ParamType.DescriptorCase) {
+            case DynamicOrderTypeDescriptor.DescriptorOneofCase.Array: param.AsArray = new DynamicOrderArray(); break;
+            case DynamicOrderTypeDescriptor.DescriptorOneofCase.Enumerated: param.AsEnumerated = new DynamicOrderEnumerated { EnumValue = descriptor.ParamType.Enumerated.Element.FirstOrDefault() }; break;
+            case DynamicOrderTypeDescriptor.DescriptorOneofCase.Primitive:
+               switch (descriptor.ParamType.Primitive) {
+                  case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveBool: param.AsBool = false; break;
+                  case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveDouble: param.AsDouble = 0.0; break;
+                  case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveInt: param.AsInt32 = 0; break;
+                  case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveOrderDef: param.AsOrderDef = new CustomOrderDefinition(); break;
+                  case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveString: param.AsString = string.Empty; break;
+                  case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveUint: param.AsUint32 = 0u; break;
+               }
+               break;
+            case DynamicOrderTypeDescriptor.DescriptorOneofCase.Structure: param.AsStruct = new DynamicOrderStruct(); break;
+         }
+         return param;
+      }
   }
-}
+}
@@ -3,13 +3,21 @@ using Google.Protobuf.Reflection;
 using mbts.ui.shell;
 using mbts.utils;
 using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Linq;

 namespace mbts.spark {
-   abstract class DynamicOrderParamVM : ViewModelBase {
-      DynamicOrderParam _param = new DynamicOrderParam();
+   abstract class DynamicOrderParamVM : DisposableViewModelBase {
+      DynamicOrderParam _param;

-      protected DynamicOrderParamVM(DynamicOrderParamDescriptor descriptor) =>
+      protected DynamicOrderParamVM(DynamicOrderParamDescriptor descriptor)
+         : this(descriptor, DynamicOrderHelper.init_param(descriptor)) { }
+
+      protected DynamicOrderParamVM(DynamicOrderParamDescriptor descriptor, DynamicOrderParam param) {
         this.descriptor = descriptor;
+         _param = param;
+      }

      public DynamicOrderParamDescriptor descriptor { get; set; }
      public DynamicOrderParam param {
@@ -34,6 +42,7 @@ namespace mbts.spark {
                  case DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveString: return new DynamicOrderParamVM<string>(descriptor, DynamicOrderParam.AsStringFieldNumber);
                  default: throw ExceptionBuilder.Argument.unexpected_case(descriptor.ParamType.Primitive, nameof(descriptor));
               }
+            case DynamicOrderTypeDescriptor.DescriptorOneofCase.Enumerated: return new DynamicOrderEnumeratedVM(descriptor);
            default: throw ExceptionBuilder.Argument.unexpected_case(descriptor.ParamType.DescriptorCase, nameof(descriptor));
         }
      }
@@ -55,4 +64,41 @@ namespace mbts.spark {

      protected override void on_param_changed() => RaisePropertyChanged(nameof(value));
   }
+
+   class DynamicOrderEnumeratedVM : DynamicOrderParamVM {
+      static readonly FieldDescriptor _field_desc = DynamicOrderParam.Descriptor.FindFieldByNumber(DynamicOrderParam.AsEnumeratedFieldNumber);
+
+      public DynamicOrderEnumeratedVM(DynamicOrderParamDescriptor descriptor)
+         : base(descriptor) =>
+         elements = new ObservableCollection<string>(_get_elements(descriptor));
+
+      public ObservableCollection<string> elements { get; }
+
+      public string selected_element {
+         get => param?.ValueCase == DynamicOrderParam.ValueOneofCase.AsEnumerated ? param.AsEnumerated.EnumValue : null;
+         set {
+            if (param == null) {
+               param = new DynamicOrderParam { AsEnumerated = new DynamicOrderEnumerated() };
+            } else if (param.ValueCase != DynamicOrderParam.ValueOneofCase.AsEnumerated) {
+               param.AsEnumerated = new DynamicOrderEnumerated();
+            }
+            if (param.AsEnumerated.EnumValue != value) {
+               param.AsEnumerated.EnumValue = value;
+               RaisePropertyChanged();
+            }
+         }
+      }
+
+      protected override void on_param_changed() {
+         _sync_elements();
+         RaisePropertyChanged(nameof(selected_element));
+      }
+
+      static IEnumerable<string> _get_elements(DynamicOrderParamDescriptor descriptor) =>
+         descriptor.ParamType?.DescriptorCase == DynamicOrderTypeDescriptor.DescriptorOneofCase.Enumerated ?
+            descriptor.ParamType.Enumerated.Element : Enumerable.Empty<string>();
+
+      void _sync_elements() =>
+         elements.sync_with(_get_elements(descriptor));
+   }
 }
@@ -33,7 +33,10 @@ namespace mbts.spark {
               }),
               ObservableAutoWrapper.connect_item_hooks(_parameters, p => {
                  p.PropertyChanged += on_param_prop_changed;
-                  return Disposable.Create(() => p.PropertyChanged -= on_param_prop_changed);
+                  return Disposable.Create(() => {
+                     p.PropertyChanged -= on_param_prop_changed;
+                     p.Dispose();
+                  });
               }, true));
            void on_param_prop_changed(object sender, PropertyChangedEventArgs e) => raise_definition_changed();
         }
@@ -61,4 +64,4 @@ namespace mbts.spark {
            (desc.ParamType.DescriptorCase == DynamicOrderTypeDescriptor.DescriptorOneofCase.Primitive && desc.ParamType.Primitive != DynamicOrderPrimitiveDescriptor.DynamicOrderPrimitiveOrderDef);
      }
   }
-}
+}
@@ -22,17 +22,14 @@ namespace mbts.spark {
      CustomOrderDefinition.CustomOneofCase order_type { get; }
      bool is_bts_type { get; }
      OrderMetadata meta { get; }
+      AlgoEditingPermissions editing_permissions { get; }
      bool can_expand { get; }
      bool is_expanded { get; set; }
-      bool can_edit_values { get; }
-      bool can_edit_structure { get; }
-      bool can_save_values { get; }
-      bool can_save_structure { get; }
      string display_name { get; }
      CustomOrderDefinitionImmutable definition { get; }
      ObservableCollection<IAlgoSelector> child_algo_selectors { get; }
+      dynamic children_vm { get; }
      bool key_match(KeyEventArgs e);
-      void set_permissions(AlgoEditingPermissions editing_permissions);
      Task<CustomOrderDefinitionImmutable?> load_from_async(CustomOrderDefinitionImmutable definition);
   }

@@ -91,4 +88,4 @@ namespace mbts.spark {
            ObservableAutoWrapper.connect_item_hooks(vm.child_algo_selectors, s => load_algo_data_recursive(s, algo_data, default_algo)));
      }
   }
-}
+}
@@ -56,8 +56,6 @@ namespace mbts.spark {
      public static IAlgoVM create(AlgoData def_data, AlgoEditingPermissions editing_permissions = default_editing_permissions, bool is_expanded = false) {
         var vm = create(def_data.key, def_data.name, def_data.value.CustomCase, editing_permissions, is_expanded);
         vm.load_from(def_data.value);
-         //vm.is_expanded = is_expanded && vm.can_expand;
-         vm.is_expanded = is_expanded && vm.can_expand;
         return vm;
      }

@@ -84,6 +82,7 @@ namespace mbts.spark {
            case AlgoType.None: vm = new DefaultAlgoVM(); break;
            default: throw new NotImplementedException();
         }
+         vm.is_expanded = is_expanded && vm.can_expand;
         return vm;
      }

@@ -95,38 +94,32 @@ namespace mbts.spark {
         public static FieldDescriptor find_descriptor<T>() =>
            _algo_type_index.TryGetValue(typeof(T), out FieldDescriptor fd) ?
               fd : throw new NotSupportedException($"No {nameof(AlgoDef)} {nameof(FieldDescriptor)} exists for type '{typeof(T)}.'");
-
-         public static Func<TMutable, TImmutable> immutable_factory<TMutable, TImmutable>() where TMutable : IMessage, new() where TImmutable : IImmutableMessage =>
-            _ImmutableActivator<TMutable, TImmutable>.factory;
-
-         static class _ImmutableActivator<TMutable, TImmutable> where TMutable : IMessage, new() where TImmutable : IImmutableMessage {
-            public static readonly Func<TMutable, TImmutable> factory =
-               m => (TImmutable)Activator.CreateInstance(typeof(TImmutable), m);
-         }
      }

      #region OrderTypeVM Base Classes
-      abstract class OrderTypeVMBase<TMutable, TImmutable> : DisposableViewModelBase, IAlgoVM, IObserver<SecurityMD?>, IObserver<OrdersModel> where TMutable : class, IMessage, new() where TImmutable : struct, IImmutableMessage {
-         /// TODO: maybe use explicit delegates rather than rely on reflection <see cref="_descriptor"/> <see cref="_create_immutable"/>.
+      abstract class OrderTypeVMBase<TMutable, TImmutable> : DisposableViewModelBase, IAlgoVM,
+         IObserver<SecurityMD?>,
+         IObserver<SecurityImmutable?>,
+         IObserver<OrdersModel>,
+         IObserver<AlgoEditingPermissions> where TMutable : class, IMessage, new() where TImmutable : struct, IImmutableMessage {
         static readonly FieldDescriptor _descriptor = OrderTypeVMUtils.find_descriptor<TMutable>();
-         static readonly Func<TMutable, TImmutable> _create_immutable = OrderTypeVMUtils.immutable_factory<TMutable, TImmutable>();
         readonly IDictionary<string, object> _children_vm = new ExpandoObject();
         protected CompositeDisposable _resources = new CompositeDisposable();

         readonly ObservableKeyedCollection<(string name, Action<TMutable> assign, Action<TMutable> load), string> _auto_props = new ObservableKeyedCollection<(string name, Action<TMutable> assign, Action<TMutable> load), string>(t => t.name);
         readonly ObservableKeyedCollection<AlgoSelectorData, string> _child_algo_selector_data = new ObservableKeyedCollection<AlgoSelectorData, string>(sd => sd.prop_name);
         readonly ObservableAutoWrapper<IAlgoSelector, AlgoSelectorData> _child_algo_selectors;
-         readonly Property<bool> _is_expanded, _can_save_values, _can_save_structure;
+         readonly Property<bool> _is_expanded;
         readonly DeferrableActionWrapper _def_change_notifier;
+         SecurityInput _security_input;
+         AlgoEditingPermissions _editing_permissions;
         IDisposable _pending_load;

         protected OrderTypeVMBase(AlgoKey id, string display_name, AlgoEditingPermissions editing_permissions) {
            this.id = id;
            this.display_name = display_name;
-            this.editing_permissions = editing_permissions;
+            _editing_permissions = editing_permissions;
            _child_algo_selectors = new ObservableAutoWrapper<IAlgoSelector, AlgoSelectorData>(_child_algo_selector_data, sd => sd.selector);
-            _can_save_values = backing(nameof(can_save_values), true);
-            _can_save_structure = backing(nameof(can_save_structure), true);
            _is_expanded = backing<bool>(nameof(is_expanded));
            meta = OrderDataHelper.get_metadata(order_type);
            _def_change_notifier = new DeferrableActionWrapper(() => definition_changed?.Invoke());
@@ -134,10 +127,6 @@ namespace mbts.spark {
               switch (e.PropertyName) {
                  // ignore props that don't affect the resultant AlgoDef
                  case nameof(is_expanded):
-                  case nameof(can_edit_values):
-                  case nameof(can_edit_structure):
-                  case nameof(can_save_values):
-                  case nameof(can_save_structure):
                     return;
                  default:
                     _def_change_notifier.execute();
@@ -148,10 +137,7 @@ namespace mbts.spark {
               CompositeDisposable def_sub = null;
               sd.selector.selected_algo_changed += subscribe_new_algo;
               return new CompositeDisposable(
-                  ObservableAutoWrapper.connect_item_hooks(sd.selector.algos, a => {
-                     a.set_permissions(this.editing_permissions);
-                     return a as IDisposable ?? Disposable.empty;
-                  }, true)) {
+                  ObservableAutoWrapper.try_dispose_on_removed(sd.selector.algos, true)) {
                  () => {
                     sd.selector.selected_algo_changed -= subscribe_new_algo;
                     Disposable.dispose(ref def_sub);
@@ -170,6 +156,7 @@ namespace mbts.spark {
         }

         public event Action definition_changed;
+         event Action<SecurityImmutable?> _security_changed;
         // core
         public AlgoDefi definition => new AlgoDefi(this.created_assigned());
         public AlgoType order_type => OrderDataHelper.get_order_type(new TMutable());
@@ -182,18 +169,14 @@ namespace mbts.spark {
         public dynamic children_vm => _children_vm;
         public ObservableCollection<IAlgoSelector> child_algo_selectors => _child_algo_selectors;
         // editing permissions
-         public AlgoEditingPermissions editing_permissions { get; private set; }
-         public bool can_edit_values => EnumHelper.includes_flag(editing_permissions, AlgoEditingPermissions.AllowEditValues);
-         public bool can_edit_structure => EnumHelper.includes_flag(editing_permissions, AlgoEditingPermissions.AllowEditStructure);
-         public bool can_save_values => _can_save_values.Value;
-         public bool can_save_structure => _can_save_structure.Value;
-         // misc
+         public AlgoEditingPermissions editing_permissions { get => _editing_permissions; private set => Set(ref _editing_permissions, value); }
+         // expand
         public virtual bool can_expand => !meta.NoProps;
         public virtual bool is_expanded { get => _is_expanded.Value; set => _is_expanded.Value = value; }
         // protected (observed props)
         protected OrdersModel model { get; private set; }
-         protected SecurityMD? security_md { get; private set; }
-         protected SecurityImmutable? security => security_md?.security;
+         protected SecurityMD? security_md => _security_input.security_md;
+         protected SecurityImmutable? security => _security_input.security;

         public void assign_to(AlgoDef value) {
            var algo = new TMutable();
@@ -206,12 +189,6 @@ namespace mbts.spark {
            }
         }

-         public void set_permissions(AlgoEditingPermissions editing_permissions) {
-            using (detect_property_changes(nameof(can_edit_values), nameof(can_edit_structure), nameof(can_save_values), nameof(can_save_structure)))
-               this.editing_permissions = editing_permissions;
-            on_permissions_changed();
-         }
-
         public bool key_match(KeyEventArgs key) =>
            !string.IsNullOrEmpty(display_name) && key.Key == (Key.A + display_name[0] - 'A');

@@ -219,22 +196,31 @@ namespace mbts.spark {
            if (value.CustomCase != order_type)
               return;
            var algom = _descriptor.Accessor.GetValue(value.CloneToMutable()) as TMutable ?? new TMutable();
+            var security_src = Observable.Create<SecurityImmutable?>(o => {
+               o.OnNext(security);
+               _security_changed += o.OnNext;
+               return Disposable.Create(() => _security_changed -= o.OnNext);
+            });
            Disposable.replace(ref _pending_load,
-               new CompositeDisposable(
-                  ObservableAutoWrapper.connect_item_actions(_child_algo_selector_data.AsCollection(), sd => {
-                     var inner_def = sd.get_order(value);
-                     if (inner_def.HasValue) {
-                        if (security.HasValue) {
-                           inner_def = OrderDataHelper.fit_to_type(inner_def.Value, security.Value.ContractCase);
-                           if (!inner_def.HasValue)
-                              return;
-                        }
-                        var vm = sd.selector.algos.GetOrAdd(OrderDataHelper.get_shallow_factory_key(inner_def.Value), k => create(k, inner_def.Value.display_name(), inner_def.Value.CustomCase));
-                        vm.load_from(inner_def.Value);
-                        sd.selector.selected_algo = vm;
-                     }
-                  }),
+               Disposable.Create(
+                  ObservableAutoWrapper.connect_item_hooks(
+                     _child_algo_selector_data.AsCollection(),
+                     sd => security_src.Subscribe(_ => ObservableAutoWrapper.connect_item_actions(_child_algo_selector_data.AsCollection(), selector_load_impl))),
                  ObservableAutoWrapper.connect_item_actions(_auto_props.AsCollection(), p => p.load(algom))));
+
+            void selector_load_impl(AlgoSelectorData sd) {
+               var inner_def = sd.get_order(value);
+               if (inner_def.HasValue) {
+                  if (security.HasValue) {
+                     inner_def = OrderDataHelper.fit_to_type(inner_def.Value, security.Value.ContractCase);
+                     if (!inner_def.HasValue)
+                        return;
+                  }
+                  var vm = sd.selector.algos.GetOrAdd(OrderDataHelper.get_shallow_factory_key(inner_def.Value), k => create(k, inner_def.Value.display_name(), inner_def.Value.CustomCase, is_expanded: is_expanded));
+                  vm.load_from(inner_def.Value);
+                  sd.selector.selected_algo = vm;
+               }
+            }
         }

         public virtual async Task<AlgoDefi?> load_from_async(AlgoDefi defi) {
@@ -246,7 +232,7 @@ namespace mbts.spark {
               foreach (var sd in _child_algo_selector_data) {
                  var inner_def = sd.get_order(defi);
                  if (inner_def.HasValue) {
-                     var vm = sd.selector.algos.GetOrAdd(OrderDataHelper.get_shallow_factory_key(inner_def.Value), k => create(k, inner_def.Value.display_name(), inner_def.Value.CustomCase));
+                     var vm = sd.selector.algos.GetOrAdd(OrderDataHelper.get_shallow_factory_key(inner_def.Value), k => create(k, inner_def.Value.display_name(), inner_def.Value.CustomCase, is_expanded: is_expanded));
                     await vm.load_from_async(inner_def.Value);
                     sd.selector.selected_algo = vm;
                  }
@@ -260,11 +246,6 @@ namespace mbts.spark {

         protected virtual Task on_load_from_async(AlgoDefi defi) => Task.CompletedTask;

-         protected virtual void on_permissions_changed() {
-            foreach (var vm in child_algo_selectors.SelectMany(s => s.algos.AsCollection()))
-               vm.set_permissions(editing_permissions);
-         }
-
         protected void raise_definition_changed() =>
            _def_change_notifier.execute();

@@ -337,12 +318,11 @@ namespace mbts.spark {
         protected Property<TImmutableValue> add_property<TMutableValue, TImmutableValue>(string prop_name, int target_field_number, TImmutableValue init_value = default) where TMutableValue : class, IMessage, new() where TImmutableValue : IImmutableMessage {
            var prop = backing(prop_name, init_value);
            var field_desc = new TMutable().Descriptor.FindFieldByNumber(target_field_number);
-            var immutable_factory = OrderTypeVMUtils.immutable_factory<TMutableValue, TImmutableValue>();
            add_property<TMutableValue>(
               prop_name,
               mdef => field_desc.Accessor.GetValue(mdef) as TMutableValue,
               (mdef, mval) => field_desc.Accessor.SetValue(mdef, mval),
-               mval => prop.set(immutable_factory(mval ?? new TMutableValue())),
+               mval => prop.set(ProtoHelper.immutable_factory<TMutableValue, TImmutableValue>(mval ?? new TMutableValue())),
               () => {
                  // TODO: perhaps CloneToMutable() should be a member of IImmutableMessage.
                  // this method makes things so simple for the caller...but this dynamic cast is a little sketch.
@@ -381,6 +361,7 @@ namespace mbts.spark {

         protected virtual void on_model_internal() { }
         protected virtual void on_security_md_internal() { }
+         protected virtual void on_security_internal() { }

         // model
         void IObserver<OrdersModel>.OnNext(OrdersModel model) {
@@ -400,14 +381,40 @@ namespace mbts.spark {
         void IObserver<OrdersModel>.OnCompleted() { }
         // security md
         void IObserver<SecurityMD?>.OnNext(SecurityMD? security_md) {
-            this.security_md = security_md;
-            using (_def_change_notifier.defer_execution()) {
-               on_security_md_internal();
-               _populate_selectors();
-            }
+            using (_def_change_notifier.defer_execution())
+            using (_update_sec_input())
+               _security_input = _security_input.with_security_md(security_md);
         }
         void IObserver<SecurityMD?>.OnError(Exception error) { }
         void IObserver<SecurityMD?>.OnCompleted() { }
+         // security
+         void IObserver<SecurityImmutable?>.OnNext(SecurityImmutable? security) {
+            using (_def_change_notifier.defer_execution())
+            using (_update_sec_input())
+               _security_input = _security_input.with_security(security);
+         }
+
+         void IObserver<SecurityImmutable?>.OnError(Exception error) { }
+         void IObserver<SecurityImmutable?>.OnCompleted() { } 
+         // editing permissions
+         void IObserver<AlgoEditingPermissions>.OnNext(AlgoEditingPermissions editing_permissions) => this.editing_permissions = editing_permissions;
+         void IObserver<AlgoEditingPermissions>.OnError(Exception error) { }
+         void IObserver<AlgoEditingPermissions>.OnCompleted() { }
+
+         IDisposable _update_sec_input() {
+            var old_sec = security;
+            var old_sec_md = security_md;
+            return Disposable.Create(() => {
+               if (security != old_sec) {
+                  on_security_internal();
+                  if (_editing_permissions.HasFlag(AlgoEditingPermissions.AllowEditStructure))
+                     _populate_selectors();
+                  _security_changed?.Invoke(security);
+               }
+               if (security_md != old_sec_md)
+                  on_security_md_internal();
+            });
+         }

         IDisposable _selector_data_hooks;
         void _populate_selectors() {
@@ -426,6 +433,40 @@ namespace mbts.spark {
         }
      }

+      // security input may come in 2 forms:
+      //    1) SecurityImmutable?
+      //    2) SecurityMD?
+      // This structure resolves conflicts that may arise from the different inputs
+      struct SecurityInput {
+         readonly SecurityMD? _raw_security_md;
+         readonly SecurityImmutable? _raw_security;
+
+         public readonly SecurityMD? security_md;
+         public readonly SecurityImmutable? security;
+
+         SecurityInput(SecurityImmutable? raw_security, SecurityMD? raw_security_md, SecurityImmutable? security, SecurityMD? security_md) {
+            _raw_security = raw_security;
+            _raw_security_md = raw_security_md;
+            this.security_md = security_md;
+            this.security = security;
+         }
+
+         public SecurityInput with_security(SecurityImmutable? security) =>
+            new SecurityInput(
+               security,
+               _raw_security_md,
+               security,
+               security.HasValue && _raw_security_md.HasValue && _raw_security_md.Value.security.Id != security.Value.Id ?
+                  null : _raw_security_md);
+
+         public SecurityInput with_security_md(SecurityMD? security_md) =>
+            new SecurityInput(
+               _raw_security,
+               security_md,
+               security_md?.security ?? _raw_security,
+               security_md);
+      }
+
      struct AlgoSelectorData {
         public readonly string prop_name;
         public readonly AlgoSelector selector;
@@ -445,14 +486,15 @@ namespace mbts.spark {
         IReadOnlyDictionary<AlgoKey, AlgoData> _pending_data;
         AlgoKey? _pending_default;

-         public AlgoSelector() =>
+         public AlgoSelector() {
            algos_view = ObservableAutoWrapper.create_sorted_wrapper(algos, AlgoCollectionHelper.algo_vm_comparer);
+            selected_algo_changed += (o, n) => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(selected_algo)));
+         }

         public void load_algo_data(IReadOnlyDictionary<AlgoKey, AlgoData> algo_data, AlgoKey? default_algo) {
            _pending_data = algo_data;
            _pending_default = default_algo;
            _sync_formats();
-            selected_algo_changed += (o, n) => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(selected_algo)));
         }

         public event PropertyChange<IAlgoVM> selected_algo_changed;
@@ -513,4 +555,4 @@ namespace mbts.spark {
      }
      #endregion
   }
-}
+}
@@ -1,4 +1,5 @@
 using bts;
+using bts.api;
 using bts.api.orderman;
 using mbts.ui.controls;
 using mbts.ui.utility;
@@ -11,7 +12,7 @@ using SpreaderDefi = bts.api.orderman.SpreaderOrderDefinitionImmutable;

 namespace mbts.spark {
   static partial class OrderTypeVMFactory {
-      class SpreaderOrderVM : OrderTypeVMBase<SpreaderDef, SpreaderDefi>, IAlgoVM, ILazyAlgo, IObserver<SecurityMD?>, IObserver<OrdersModel> {
+      class SpreaderOrderVM : OrderTypeVMBase<SpreaderDef, SpreaderDefi>, IAlgoVM, ILazyAlgo, IObserver<OrdersModel> {
         readonly Property<SpreaderDefi?> _template;
         readonly StrategyEditorWrapper _strategy_editor_wrapper;
         IDisposable _strategy_sub;
@@ -78,16 +79,15 @@ namespace mbts.spark {
               set_error(nameof(template), "Waiting for security and/or strategy.", true);
            else clear_error(nameof(template));
         }
-
-         protected override void on_security_md_internal() => _reset_strategy_sub();
         protected override void on_model_internal() => _reset_strategy_sub();
+         protected override void on_security_internal() => _reset_strategy_sub();

         void _reset_strategy_sub() {
            Disposable.dispose(ref _strategy_sub);
            if (model != null) {
-               if (security_md.HasValue) {
-                  _strategy_sub = model.spreader.security_strategy(security_md.Value.security.Id)
-                     .Select(strategy => new SpreaderDefi?(model.factory.spreader_orderi(security_md.Value.security, strategy)))
+               if (security.HasValue) {
+                  _strategy_sub = model.spreader.security_strategy(security.Value.Id)
+                     .Select(strategy => new SpreaderDefi?(model.factory.spreader_orderi(security.Value, strategy)))
                     .OnDispatcher()
                     .Subscribe(s => {
                        is_loaded = true;
@@ -130,4 +130,4 @@ namespace mbts.spark {
         }
      }
   }
-}
+}
@@ -86,7 +86,7 @@ namespace mbts.spark {
            (os, okey, am, mkey) => new OrderSecurityAlgoMeta(os.order, os.sec, am.algo, am.meta),
            (os, okey, mkey) => new OrderSecurityAlgoMeta(os.order, os.sec, null, null),
            ot => ot.order.Key);
-         on_order_tuples = order_secs_algo_meta_join;
+         on_order_tuples = order_secs_algo_meta_join.Cache();
         var on_fills = 
            _service.subscribei_fills()
            .Naggle(interval, scheduler)
@@ -101,17 +101,14 @@ namespace mbts.spark {
            (f, fk, o, ok) => new FillTuple(f, o),
            (f, fk, ok) => new FillTuple(f, null),
            f => f.fill.FillKey);
-         on_fill_tuples = fill_order_tuples_join;
+         on_fill_tuples = fill_order_tuples_join.Cache();
         _dispose = Disposable.Create(
            on_orders.Select(t => t.order, o => o.Key).Subscribe(_security_orders_demuxer),
            on_positions.Subscribe(_security_positions_demuxer),
-            order_secs_algo_meta_join.Connect(),
-            algo_meta_join.Connect(),
-            fill_order_tuples_join.Connect(),
            _bus.subscribe(SparkTags.CreateOrder).Subscribe(a => send_order(a.definition, a.price, a.size).ignore()),
            _bus.subscribe(SparkTags.RecreateOrder).Subscribe(a => a.ForEach(x => send_order(x.definition, x.price, x.size).ignore())),
            _bus.subscribe(SparkTags.CancelOrders).Subscribe(x => cancel_orders(x).ignore()),
-            _bus.subscribe(SparkTags.CrackOrders).Subscribe(x => crack_orders(x).ignore()),
+            _bus.subscribe(SparkTags.DetachOrders).Subscribe(x => detach_orders(x).ignore()),
            _bus.subscribe(SparkTags.UpdateOrder).Subscribe(x => this.update_order(x.key, x.price, x.size).ignore())
         );
      }
@@ -166,27 +163,37 @@ namespace mbts.spark {
         return success;
      }

-      public async Task<bool> update_order(OrderRecordImmutable order, double price, uint size) {
-         if (order.working_quantity() <= 0) return false;
-         _activity.update_order(order, price, size);
+      public async Task<bool> update_order(OrderRecordImmutable order, double? new_price = null, uint? new_size = null, CustomOrderDefinitionImmutable? new_algo = null) {
+         if (order.working_quantity() <= 0) {
+            // order already filled to completion
+            return false;
+         }
+         var size = new_size ?? (uint)order.working_quantity();
+         var price = new_price ?? order.price();
+         if (size == order.working_quantity() && price == order.price() && !new_algo.HasValue) {
+            // no parameters would be changed by this update
+            return false;
+         }
+         _activity.update_order(order, price, size, new_algo.HasValue);
         var result = await _service.update_order_async(new Update() {
            OrderKey = order.Key,
            Price = price,
-            Quantity = size
+            Quantity = size,
+            Custom = new_algo?.CloneToMutable()
         });
         (var key, string msg) = _handle_error(result, "Failed to update order: {0}");
         bool success = key.HasValue;
         if (!success) {
-            _activity.update_order_failed(order, price, size);
+            _activity.update_order_failed(order, price, size, new_algo.HasValue);
         }
         return success;
      }

-      public Task<bool[]> crack_orders(IEnumerable<uint> orders) =>
-         Task.WhenAll(orders.Select(crack_order));
+      public Task<bool[]> detach_orders(IEnumerable<uint> orders) =>
+         Task.WhenAll(orders.Select(detach_order));

-      public async Task<bool> crack_order(uint order) {
-         var result = await _service.crack_order_async(new Crack() { OrderKey = order });
+      public async Task<bool> detach_order(uint order) {
+         var result = await _service.detach_order_async(new Detach() { OrderKey = order });
         return _handle_error(result, "Failed to break order: {0}").key.HasValue;
      }

@@ -4,7 +4,7 @@ using System;

 namespace mbts {
   [ProtoContract]
-   class DiscreteStringPredicate : IDiscreteValuesPredicateBuilder<string>, IEquatable<DiscreteStringPredicate> {
+   class DiscreteStringPredicate : IDiscreteValuesPredicateData<string>, IEquatable<DiscreteStringPredicate> {
      [ProtoMember(1)]
      string[] _values;
      [ProtoMember(2)]
@@ -4,7 +4,7 @@ using System;

 namespace mbts {
   [ProtoContract]
-   class DiscreteUIntPredicate : IDiscreteValuesPredicateBuilder<uint, uint?, uint[]>, IEquatable<DiscreteUIntPredicate> {
+   class DiscreteUIntPredicate : IDiscreteValuesPredicateData<uint, uint?, uint[]>, IEquatable<DiscreteUIntPredicate> {
      [ProtoMember(1)]
      uint[] _values;
      [ProtoMember(2)]
@@ -16,7 +16,7 @@ namespace mbts {
      public uint[] not_in_set { get => _get_set(true); set => _set(true, value); }

      public DiscreteValuesOneofCase predicate_type_case => DiscreteValuesPredicateUtils.get_predicate_type_case(_values, _negated);
-      public IPredicate<uint> create(object obj) => DiscreteValuesPredicateUtils.create(this);
+      public IPredicate<uint> create() => DiscreteValuesPredicateUtils.create(this);

      public bool Equals(DiscreteUIntPredicate other) => DiscreteValuesPredicateUtils.equals(this, other);
      public override bool Equals(object obj) => Equals(obj as DiscreteUIntPredicate);
@@ -8,14 +8,14 @@ using System.Collections.Generic;
 using System.Linq;

 namespace mbts {
-   interface IDiscreteValuesPredicateBuilder<T, TSingle, TMulti> : IPredicateBuilder<T> {
+   interface IDiscreteValuesPredicateData<T, TSingle, TMulti> {
      TSingle is_value { get; set; }
      TSingle not_value { get; set; }
      TMulti in_set { get; set; }
      TMulti not_in_set { get; set; }
      DiscreteValuesOneofCase predicate_type_case { get; }
   }
-   interface IDiscreteValuesPredicateBuilder<T> : IDiscreteValuesPredicateBuilder<T, T, T[]> { }
+   interface IDiscreteValuesPredicateData<T> : IDiscreteValuesPredicateData<T, T, T[]> { }

   public enum DiscreteValuesOneofCase {
      None,
@@ -32,8 +32,8 @@ namespace mbts {

 namespace mbts.ui.settings {
   static class DiscreteValuesPredicateUtils {
-      public static bool equals<T>(IDiscreteValuesPredicateBuilder<T> a, IDiscreteValuesPredicateBuilder<T> b) => a.safe_equals(b, _equals);
-      static bool _equals<T>(IDiscreteValuesPredicateBuilder<T> a, IDiscreteValuesPredicateBuilder<T> b) {
+      public static bool equals<T>(IDiscreteValuesPredicateData<T> a, IDiscreteValuesPredicateData<T> b) => a.safe_equals(b, _equals);
+      static bool _equals<T>(IDiscreteValuesPredicateData<T> a, IDiscreteValuesPredicateData<T> b) {
         var dvoc = a.predicate_type_case;
         if (dvoc != b.predicate_type_case)
            return false;
@@ -47,8 +47,8 @@ namespace mbts.ui.settings {
         }
      }

-      public static bool equals<T, TSingle, TMulti>(IDiscreteValuesPredicateBuilder<T, TSingle, TMulti> a, IDiscreteValuesPredicateBuilder<T, TSingle, TMulti> b) => a.safe_equals(b, _equals);
-      public static bool _equals<T, TSingle, TMulti>(IDiscreteValuesPredicateBuilder<T, TSingle, TMulti> a, IDiscreteValuesPredicateBuilder<T, TSingle, TMulti> b) {
+      public static bool equals<T, TSingle, TMulti>(IDiscreteValuesPredicateData<T, TSingle, TMulti> a, IDiscreteValuesPredicateData<T, TSingle, TMulti> b) => a.safe_equals(b, _equals);
+      public static bool _equals<T, TSingle, TMulti>(IDiscreteValuesPredicateData<T, TSingle, TMulti> a, IDiscreteValuesPredicateData<T, TSingle, TMulti> b) {
         var dvoc = a.predicate_type_case;
         if (dvoc != b.predicate_type_case)
            return false;
@@ -62,7 +62,7 @@ namespace mbts.ui.settings {
         }
      }

-      public static int hash<T>(IDiscreteValuesPredicateBuilder<T> a) {
+      public static int hash<T>(IDiscreteValuesPredicateData<T> a) {
         switch (a.predicate_type_case) {
            case DiscreteValuesOneofCase.IsValue: return a.is_value.GetHashCode() % MathUtils.Primes.P_17191;
            case DiscreteValuesOneofCase.NotValue: return a.not_value.GetHashCode() % MathUtils.Primes.P_83987;
@@ -72,7 +72,7 @@ namespace mbts.ui.settings {
         }
      }

-      public static int hash<T, TSingle, TMulti>(IDiscreteValuesPredicateBuilder<T, TSingle, TMulti> a) {
+      public static int hash<T, TSingle, TMulti>(IDiscreteValuesPredicateData<T, TSingle, TMulti> a) {
         switch (a.predicate_type_case) {
            case DiscreteValuesOneofCase.IsValue: return a.is_value.GetHashCode() % MathUtils.Primes.P_17191;
            case DiscreteValuesOneofCase.NotValue: return a.not_value.GetHashCode() % MathUtils.Primes.P_83987;
@@ -88,7 +88,7 @@ namespace mbts.ui.settings {
               (negated ? DiscreteValuesOneofCase.NotValue : DiscreteValuesOneofCase.IsValue) :
               (negated ? DiscreteValuesOneofCase.NotInSet : DiscreteValuesOneofCase.IsInSet);

-      public static DiscreteValuesOneofCase get_predicate_type_case<T, TSingle, TMulti>(IDiscreteValuesPredicateBuilder<T, TSingle, TMulti> predicate_builder) {
+      public static DiscreteValuesOneofCase get_predicate_type_case<T, TSingle, TMulti>(IDiscreteValuesPredicateData<T, TSingle, TMulti> predicate_builder) {
         if (predicate_builder.is_value != null) return DiscreteValuesOneofCase.IsValue;
         if (predicate_builder.not_value != null) return DiscreteValuesOneofCase.NotValue;
         if (predicate_builder.in_set != null) return DiscreteValuesOneofCase.IsInSet;
@@ -96,7 +96,7 @@ namespace mbts.ui.settings {
         return DiscreteValuesOneofCase.None;
      }

-      public static IPredicate<T> create<T>(IDiscreteValuesPredicateBuilder<T> predicate_builder) {
+      public static IPredicate<T> create<T>(IDiscreteValuesPredicateData<T> predicate_builder) {
         switch (predicate_builder.predicate_type_case) {
            case DiscreteValuesOneofCase.IsValue: return PredicateBuilder.equals(predicate_builder.is_value);
            case DiscreteValuesOneofCase.NotValue: return PredicateBuilder.not_equals(predicate_builder.not_value);
@@ -106,7 +106,7 @@ namespace mbts.ui.settings {
         }
      }

-      public static IPredicate<T> create<T>(IDiscreteValuesPredicateBuilder<T, T?, T[]> predicate_builder) where T : struct {
+      public static IPredicate<T> create<T>(IDiscreteValuesPredicateData<T, T?, T[]> predicate_builder) where T : struct {
         switch (predicate_builder.predicate_type_case) {
            case DiscreteValuesOneofCase.IsValue: return PredicateBuilder.equals(predicate_builder.is_value.Value);
            case DiscreteValuesOneofCase.NotValue: return PredicateBuilder.not_equals(predicate_builder.not_value.Value);
@@ -118,13 +118,13 @@ namespace mbts.ui.settings {
   }
   static class DiscreteValuesPredicateVMFactory {
      public static Dictionary<DiscreteValuesOneofCase, ITemplatedPropertyWrapperVM<TPredicate>> get_oneofs_value_type<T, TPredicate>(IEnumerable<T> items)
-         where T : struct where TPredicate : IDiscreteValuesPredicateBuilder<T, T?, T[]> =>
+         where T : struct where TPredicate : IDiscreteValuesPredicateData<T, T?, T[]> =>
         //
         get_oneofs<T, T?, T[], TPredicate>(identity_view_value_collection(items), val => val.Value, val => val, vals => vals ?? Enumerable.Empty<T>(), vals => vals?.ToArray() ?? new T[0], get_identity_view);

      public static Dictionary<DiscreteValuesOneofCase, ITemplatedPropertyWrapperVM<TPredicate>> get_oneofs<T, TSingle, TMulti, TPredicate>(
         IObservableCollection<IViewValue<T>> items, Func<TSingle, T> from_single, Func<T, TSingle> to_single, Func<TMulti,IEnumerable<T>> from_multi, Func<IEnumerable<T>, TMulti> to_multi, Func<T, object> get_view)
-         where TPredicate : IDiscreteValuesPredicateBuilder<T, TSingle, TMulti> {
+         where TPredicate : IDiscreteValuesPredicateData<T, TSingle, TMulti> {
         //
         return new Dictionary<DiscreteValuesOneofCase, ITemplatedPropertyWrapperVM<TPredicate>> {
            { DiscreteValuesOneofCase.IsValue, PropertyWrapperVMUtils.create_selector_vm(
@@ -153,14 +153,14 @@ namespace mbts.ui.settings {
      public static Dictionary<DiscreteValuesOneofCase, ITemplatedPropertyWrapperVM<TPredicate>> get_oneofs<T, TKey, TSingle, TMulti, TPredicate>(
         IEnumerable<T> items, Func<T, TKey> key, Func<TSingle, TKey> from_single, Func<TKey, TSingle> to_single, Func<TMulti, IEnumerable<TKey>> from_multi, Func<IEnumerable<TKey>, TMulti> to_multi)
         where TKey : struct, IEquatable<TKey>
-         where TPredicate : IDiscreteValuesPredicateBuilder<T, TSingle, TMulti> =>
+         where TPredicate : IDiscreteValuesPredicateData<T, TSingle, TMulti> =>
         //
         get_oneofs<T, TKey, TSingle, TMulti, TPredicate>(RXCollection.from_enumerable(items.Select<T, IViewValue<T>>(v => new ViewValueTuple<T>(v, v))), key, from_single, to_single, from_multi, to_multi);

      public static Dictionary<DiscreteValuesOneofCase, ITemplatedPropertyWrapperVM<TPredicate>> get_oneofs<T, TKey, TSingle, TMulti, TPredicate>(
         IObservableCollection<IViewValue<T>> items, Func<T, TKey> key, Func<TSingle, TKey> from_single, Func<TKey, TSingle> to_single, Func<TMulti, IEnumerable<TKey>> from_multi, Func<IEnumerable<TKey>, TMulti> to_multi)
         where TKey : struct, IEquatable<TKey>
-         where TPredicate : IDiscreteValuesPredicateBuilder<T, TSingle, TMulti> {
+         where TPredicate : IDiscreteValuesPredicateData<T, TSingle, TMulti> {
         //
         return new Dictionary<DiscreteValuesOneofCase, ITemplatedPropertyWrapperVM<TPredicate>> {
            { DiscreteValuesOneofCase.IsValue, PropertyWrapperVMUtils.create_keyed_selector_vm<TPredicate, IViewValue<T>, TKey>(
@@ -5,7 +5,7 @@ using System;

 namespace mbts {
   [ProtoContract]
-   class ExchangePredicate : IDiscreteValuesPredicateBuilder<Venue, Venue?, Venue[]>, IEquatable<ExchangePredicate> {
+   class ExchangePredicate : IDiscreteValuesPredicateData<Venue, Venue?, Venue[]>, IEquatable<ExchangePredicate> {
      [ProtoMember(1)]
      Venue[] _values;
      [ProtoMember(2)]
@@ -17,7 +17,7 @@ namespace mbts {
      public Venue[] not_in_set { get => _get_set(true); set => _set(true, value); }

      public DiscreteValuesOneofCase predicate_type_case => DiscreteValuesPredicateUtils.get_predicate_type_case(_values, _negated);
-      public IPredicate<Venue> create(object obj) => DiscreteValuesPredicateUtils.create(this);
+      public IPredicate<Venue> create() => DiscreteValuesPredicateUtils.create(this);

      public bool Equals(ExchangePredicate other) => DiscreteValuesPredicateUtils.equals(this, other);
      public override bool Equals(object obj) => Equals(obj as ExchangePredicate);
@@ -5,7 +5,7 @@ using System;

 namespace mbts {
   [ProtoContract]
-   class OrderStatusPredicate : IDiscreteValuesPredicateBuilder<OrderStatus, OrderStatus?, OrderStatus[]>, IEquatable<OrderStatusPredicate> {
+   class OrderStatusPredicate : IDiscreteValuesPredicateData<OrderStatus, OrderStatus?, OrderStatus[]>, IEquatable<OrderStatusPredicate> {
      [ProtoMember(1)]
      OrderStatus[] _values;
      [ProtoMember(2)]
@@ -17,7 +17,7 @@ namespace mbts {
      public OrderStatus[] not_in_set { get => _get_set(true); set => _set(true, value); }

      public DiscreteValuesOneofCase predicate_type_case => DiscreteValuesPredicateUtils.get_predicate_type_case(_values, _negated);
-      public IPredicate<OrderStatus> create(object obj) => DiscreteValuesPredicateUtils.create(this);
+      public IPredicate<OrderStatus> create() => DiscreteValuesPredicateUtils.create(this);

      public bool Equals(OrderStatusPredicate other) => DiscreteValuesPredicateUtils.equals(this, other);
      public override bool Equals(object obj) => Equals(obj as OrderStatusPredicate);
@@ -5,7 +5,7 @@ using System;

 namespace mbts {
   [ProtoContract]
-   class OrderSubTypePredicate : IDiscreteValuesPredicateBuilder<OrderSubType, OrderSubType?, OrderSubType[]>, IEquatable<OrderSubTypePredicate> {
+   class OrderSubTypePredicate : IDiscreteValuesPredicateData<OrderSubType, OrderSubType?, OrderSubType[]>, IEquatable<OrderSubTypePredicate> {
      [ProtoMember(1)]
      OrderSubType[] _values;
      [ProtoMember(2)]
@@ -17,7 +17,7 @@ namespace mbts {
      public OrderSubType[] not_in_set { get => _get_set(true); set => _set(true, value); }

      public DiscreteValuesOneofCase predicate_type_case => DiscreteValuesPredicateUtils.get_predicate_type_case(_values, _negated);
-      public IPredicate<OrderSubType> create(object obj) => DiscreteValuesPredicateUtils.create(this);
+      public IPredicate<OrderSubType> create() => DiscreteValuesPredicateUtils.create(this);

      public bool Equals(OrderSubTypePredicate other) => DiscreteValuesPredicateUtils.equals(this, other);
      public override bool Equals(object obj) => Equals(obj as OrderSubTypePredicate);
@@ -5,7 +5,7 @@ using OrderType = bts.api.orderman.CustomOrderDefinition.CustomOneofCase;

 namespace mbts {
   [ProtoContract]
-   class OrderTypePredicate : IDiscreteValuesPredicateBuilder<OrderType, OrderType?, OrderType[]>, IEquatable<OrderTypePredicate> {
+   class OrderTypePredicate : IDiscreteValuesPredicateData<OrderType, OrderType?, OrderType[]>, IEquatable<OrderTypePredicate> {
      [ProtoMember(1)]
      OrderType[] _values;
      [ProtoMember(2)]
@@ -17,7 +17,7 @@ namespace mbts {
      public OrderType[] not_in_set { get => _get_set(true); set => _set(true, value); }

      public DiscreteValuesOneofCase predicate_type_case => DiscreteValuesPredicateUtils.get_predicate_type_case(_values, _negated);
-      public IPredicate<OrderType> create(object obj) => DiscreteValuesPredicateUtils.create(this);
+      public IPredicate<OrderType> create() => DiscreteValuesPredicateUtils.create(this);

      public bool Equals(OrderTypePredicate other) => DiscreteValuesPredicateUtils.equals(this, other);
      public override bool Equals(object obj) => Equals(obj as OrderTypePredicate);
@@ -5,7 +5,7 @@ using System;

 namespace mbts {
   [ProtoContract]
-   class TimeInForcePredicate : IDiscreteValuesPredicateBuilder<TimeInForce, TimeInForce?, TimeInForce[]>, IEquatable<TimeInForcePredicate> {
+   class TimeInForcePredicate : IDiscreteValuesPredicateData<TimeInForce, TimeInForce?, TimeInForce[]>, IEquatable<TimeInForcePredicate> {
      [ProtoMember(1)]
      TimeInForce[] _values;
      [ProtoMember(2)]
@@ -17,7 +17,7 @@ namespace mbts {
      public TimeInForce[] not_in_set { get => _get_set(true); set => _set(true, value); }

      public DiscreteValuesOneofCase predicate_type_case => DiscreteValuesPredicateUtils.get_predicate_type_case(_values, _negate);
-      public IPredicate<TimeInForce> create(object obj) => DiscreteValuesPredicateUtils.create(this);
+      public IPredicate<TimeInForce> create() => DiscreteValuesPredicateUtils.create(this);

      public bool Equals(TimeInForcePredicate other) => DiscreteValuesPredicateUtils.equals(this, other);
      public override bool Equals(object obj) => Equals(obj as TimeInForcePredicate);
@@ -4,7 +4,6 @@ using bts.shell;
 using bts.utils;
 using mbts.spark;
 using mbts.ui.settings;
-using mbts.utils;
 using ProtoBuf;
 using System;
 using System.Collections.Generic;
@@ -14,7 +13,7 @@ namespace mbts {
   static class OrderCanceledEventPredicateVMFactory {
      public static Dictionary<OrderCanceledEventPredicate.PredicateTypeOneofCase, ITemplatedPropertyWrapperVM<OrderCanceledEventPredicate>> get_oneofs(IBus bus) =>
         new Dictionary<OrderCanceledEventPredicate.PredicateTypeOneofCase, ITemplatedPropertyWrapperVM<OrderCanceledEventPredicate>> {
-            { OrderCanceledEventPredicate.PredicateTypeOneofCase.AnyOrder, PredicateBuilderVMWrapper.create<OrderCanceledEventPredicate>(p => p.security = null) },
+            { OrderCanceledEventPredicate.PredicateTypeOneofCase.AnyOrder, PredicateVMWrapper.create<OrderCanceledEventPredicate>(p => p.security = null) },
            { OrderCanceledEventPredicate.PredicateTypeOneofCase.SecurityOrder, SecurityCriteriaVMFactory.create<OrderCanceledEventPredicate>(bus, o => o.security?.is_value ?? new SecurityCriteria(),
               (p, s) => {
                  if (p.security == null)
@@ -26,7 +25,7 @@ namespace mbts {
   }

   [ProtoContract]
-   class OrderCanceledEventPredicate : IPredicateBuilder<OrderSecurity, INotificationServiceDataCache>, IEquatable<OrderCanceledEventPredicate> {
+   class OrderCanceledEventPredicate : IEquatable<OrderCanceledEventPredicate> {
      public enum PredicateTypeOneofCase {
         [Description("(any order)")]
         AnyOrder,
@@ -52,7 +51,7 @@ namespace mbts {
         OrderEventPredicateHelper.create_status_transition_predicate(OrderStatus.Canceled, security, data_cache);

      public INotificationPredicate<OrderSecurity> create_toast(INotificationServiceDataCache data_cache) =>
-         new MyToaster(security?.create(data_cache), data_cache);
+         new MyToaster(security?.create(), data_cache);

      public bool Equals(OrderCanceledEventPredicate other) => other != null && other.security.safe_equals(other.security);
      public override bool Equals(object obj) => Equals(obj as OrderCanceledEventPredicate);
@@ -4,7 +4,6 @@ using bts.shell;
 using bts.utils;
 using mbts.spark;
 using mbts.ui.settings;
-using mbts.utils;
 using ProtoBuf;
 using System;
 using System.Collections.Generic;
@@ -14,7 +13,7 @@ namespace mbts {
   static class OrderCompletedEventPredicateVMFactory {
      public static Dictionary<OrderCompletedEventPredicate.PredicateTypeOneofCase, ITemplatedPropertyWrapperVM<OrderCompletedEventPredicate>> get_oneofs(IBus bus) =>
         new Dictionary<OrderCompletedEventPredicate.PredicateTypeOneofCase, ITemplatedPropertyWrapperVM<OrderCompletedEventPredicate>> {
-            { OrderCompletedEventPredicate.PredicateTypeOneofCase.AnyOrder, PredicateBuilderVMWrapper.create<OrderCompletedEventPredicate>(p => p.security = null) },
+            { OrderCompletedEventPredicate.PredicateTypeOneofCase.AnyOrder, PredicateVMWrapper.create<OrderCompletedEventPredicate>(p => p.security = null) },
            { OrderCompletedEventPredicate.PredicateTypeOneofCase.SecurityOrder, SecurityCriteriaVMFactory.create<OrderCompletedEventPredicate>(bus, o => o.security?.is_value ?? new SecurityCriteria(),
               (p, s) => {
                  if (p.security == null)
@@ -26,7 +25,7 @@ namespace mbts {
   }

   [ProtoContract]
-   class OrderCompletedEventPredicate : IPredicateBuilder<OrderSecurity, INotificationServiceDataCache>, IEquatable<OrderCompletedEventPredicate> {
+   class OrderCompletedEventPredicate : IEquatable<OrderCompletedEventPredicate> {
      public enum PredicateTypeOneofCase {
         [Description("(any order)")]
         AnyOrder,
@@ -52,7 +51,7 @@ namespace mbts {
         OrderEventPredicateHelper.create_status_transition_predicate(OrderStatus.Completed, security, data_cache);

      public INotificationPredicate<OrderSecurity> create_toast(INotificationServiceDataCache data_cache) =>
-         new MyToaster(security?.create(data_cache), data_cache);
+         new MyToaster(security?.create(), data_cache);

      public bool Equals(OrderCompletedEventPredicate other) => other != null && other.security.safe_equals(other.security);
      public override bool Equals(object obj) => Equals(obj as OrderCompletedEventPredicate);
@@ -2,8 +2,6 @@
 using bts.api.orderman;
 using bts.shell;
 using bts.utils;
-using mbts.spark;
-using mbts.utils;
 using System;

 namespace mbts {
@@ -39,7 +37,7 @@ namespace mbts {
      }

      public static IPredicate<OrderSecurity> create_status_transition_predicate(OrderStatus status, SecurityPredicate security_predicate, INotificationServiceDataCache data_cache) =>
-         new OrderStatusTransitionPredicate(status, security_predicate?.create(data_cache), data_cache);
+         new OrderStatusTransitionPredicate(status, security_predicate?.create(), data_cache);

      class OrderStatusTransitionPredicate : IPredicate<OrderSecurity>, IEquatable<OrderStatusTransitionPredicate> {
         readonly IPredicate<SecurityImmutable> _security_predicate;
@@ -11,7 +11,7 @@ namespace mbts {
   static class OrderFilledEventPredicateVMFactory {
      public static Dictionary<OrderFilledEventPredicate.PredicateTypeOneofCase, ITemplatedPropertyWrapperVM<OrderFilledEventPredicate>> get_oneofs(IBus bus) =>
         new Dictionary<OrderFilledEventPredicate.PredicateTypeOneofCase, ITemplatedPropertyWrapperVM<OrderFilledEventPredicate>> {
-            { OrderFilledEventPredicate.PredicateTypeOneofCase.AnyOrder, PredicateBuilderVMWrapper.create<OrderFilledEventPredicate>(p => p.security = null) },
+            { OrderFilledEventPredicate.PredicateTypeOneofCase.AnyOrder, PredicateVMWrapper.create<OrderFilledEventPredicate>(p => p.security = null) },
            { OrderFilledEventPredicate.PredicateTypeOneofCase.SecurityOrder, SecurityCriteriaVMFactory.create<OrderFilledEventPredicate>(bus, o => o.security?.is_value ?? new SecurityCriteria(),
               (p, s) => {
                  if (p.security == null) {
@@ -24,7 +24,7 @@ namespace mbts {
   }

   [ProtoContract]
-   class OrderFilledEventPredicate : IPredicateBuilder<OrderSecurity, INotificationServiceDataCache>, IEquatable<OrderFilledEventPredicate> {
+   class OrderFilledEventPredicate : IEquatable<OrderFilledEventPredicate> {
      public enum PredicateTypeOneofCase {
         [PredicateCase("(any order)")]
         AnyOrder,
@@ -59,7 +59,7 @@ namespace mbts {
      public override int GetHashCode() => security == null ? 0 : security.GetHashCode();

      FillTriggerModel _create_model(INotificationServiceDataCache nsdc) =>
-         new FillTriggerModel(nsdc, security?.create(nsdc));
+         new FillTriggerModel(nsdc, security?.create());

      class FillTriggerModel {
         readonly IPredicate<SecurityImmutable> _security_predicate;
@@ -56,16 +56,16 @@ namespace mbts {
            Func<TChildPredicate, TChildPredicateOneof> key,
            Dictionary<TChildPredicateOneof, ITemplatedPropertyWrapperVM<TChildPredicate>> oneofs) where TChildPredicateOneof : struct where TChildPredicate : new() =>
            //
-            PredicateBuilderVMWrapper.wrap_child_oneof<OrderRecordTuplePredicate, TChildPredicate, TChildPredicateOneof>(get, set, key, oneofs);
+            PredicateVMWrapper.wrap_child_oneof<OrderRecordTuplePredicate, TChildPredicate, TChildPredicateOneof>(get, set, key, oneofs);
      }
   }
 
   [ProtoContract]
-   class OrderRecordTuplePredicate : INotificationPredicateBuilder<OrderSecurity, INotificationServiceDataCache>, IEquatable<OrderRecordTuplePredicate> {
+   class OrderRecordTuplePredicate : IEquatable<OrderRecordTuplePredicate> {
      SecurityPredicate _security;
      SidePredicate _side;
      DoublePredicate _price, _last_price, _avg_price;
-      UIntPredicate _quantity, _filled_quantity, _security_key, _order_key, _parent_key;
+      UIntPredicate _quantity, _filled_quantity, _security_key, _order_key, _parent_key, _attached_target_order_key;
      OrderStatusPredicate _order_status;
      OrderTypePredicate _order_type;
      OrderSubTypePredicate _order_sub_type;
@@ -125,7 +125,9 @@ namespace mbts {
         [PredicateCase("When order is completed", PredicateCategory.Event)]
         CompletedEvent,
         [PredicateCase("When order is canceled", PredicateCategory.Event)]
-         CanceledEvent
+         CanceledEvent,
+         [PredicateCase(is_toastable:false)]
+         AttachedTargetOrderKey
      }

      [ProtoMember(1)]
@@ -176,6 +178,8 @@ namespace mbts {
      public OrderCanceledEventPredicate canceled_event { get => _canceled_event; set => _set(ref _canceled_event, value); }
      [ProtoMember(24)]
      public bool is_toast_enabled { get; set; }
+      [ProtoMember(25)]
+      public UIntPredicate attached_order_target_key { get => _attached_target_order_key; set => _set(ref _attached_target_order_key, value); }

      public PTOC predicate_type_case {
         get {
@@ -202,45 +206,44 @@ namespace mbts {
            if (_filled_event != null) return PTOC.FilledEvent;
            if (_completed_event != null) return PTOC.CompletedEvent;
            if (_canceled_event != null) return PTOC.CanceledEvent;
+            if (_attached_target_order_key != null) return PTOC.AttachedTargetOrderKey;
            return PTOC.None;
         }
      }

      public IPredicate<OrderSecurity> create_predicate(INotificationServiceDataCache data_cache) {
         switch (predicate_type_case) {
-            case PTOC.Security: return wrap(_security, r => r.security ?? SecurityDataHelper.Defaults.SecurityImmutable);
-            case PTOC.Time: return wrap(_time_created, r => r.order.created());
-            case PTOC.LastChange: return wrap(_last_change, r => r.order.last_change());
-            case PTOC.User: return wrap(_user, r => r.order.user_id());
-            case PTOC.Account: return wrap(_account, r => r.order.account_id());
-            case PTOC.Exchange: return wrap(_exchange, r => r.security.exchange_or_default());
-            case PTOC.TimeInForce: return wrap(_time_in_force, r => r.order.time_in_force());
-            case PTOC.OrderType: return wrap(_order_type, r => r.order.order_type());
-            case PTOC.SubType: return wrap(_order_sub_type, r => r.order.sub_type());
-            case PTOC.Side: return wrap(_side, r => r.order.side());
-            case PTOC.Size: return wrap(_quantity, r => r.order.quantity());
-            case PTOC.Price: return wrap(_price, r => r.order.price());
-            case PTOC.Filled: return wrap(_filled_quantity, r => r.order.filled());
-            case PTOC.AvgFilled: return wrap(_avg_price, r => r.order.avg_price());
-            case PTOC.LastPrice: return wrap(_last_price, r => r.order.last_price());
-            case PTOC.Status: return wrap(_order_status, r => r.order.status());
-            case PTOC.LastMessage: return wrap(_last_message, r => r.order.last_msg());
-            case PTOC.SecurityKey: return wrap(_security_key, r => r.order.security_key());
-            case PTOC.OrderKey: return wrap(_order_key, r => r.order.Key);
-            case PTOC.ParentKey: return wrap(_parent_key, r => r.order.ParentKey);
+            case PTOC.Security: return wrap(_security.create(), r => r.security ?? SecurityDataHelper.Defaults.SecurityImmutable);
+            case PTOC.Time: return wrap(_time_created.create(), r => r.order.created());
+            case PTOC.LastChange: return wrap(_last_change.create(), r => r.order.last_change());
+            case PTOC.User: return wrap(_user.create(), r => r.order.user_id());
+            case PTOC.Account: return wrap(_account.create(), r => r.order.account_id());
+            case PTOC.Exchange: return wrap(_exchange.create(), r => r.security.exchange_or_default());
+            case PTOC.TimeInForce: return wrap(_time_in_force.create(), r => r.order.time_in_force());
+            case PTOC.OrderType: return wrap(_order_type.create(), r => r.order.order_type());
+            case PTOC.SubType: return wrap(_order_sub_type.create(), r => r.order.sub_type());
+            case PTOC.Side: return wrap(_side.create(), r => r.order.side());
+            case PTOC.Size: return wrap(_quantity.create(), r => r.order.quantity());
+            case PTOC.Price: return wrap(_price.create(), r => r.order.price());
+            case PTOC.Filled: return wrap(_filled_quantity.create(), r => r.order.filled());
+            case PTOC.AvgFilled: return wrap(_avg_price.create(), r => r.order.avg_price());
+            case PTOC.LastPrice: return wrap(_last_price.create(), r => r.order.last_price());
+            case PTOC.Status: return wrap(_order_status.create(), r => r.order.status());
+            case PTOC.LastMessage: return wrap(_last_message.create(), r => r.order.last_msg());
+            case PTOC.SecurityKey: return wrap(_security_key.create(), r => r.order.security_key());
+            case PTOC.OrderKey: return wrap(_order_key.create(), r => r.order.Key);
+            case PTOC.ParentKey: return wrap(_parent_key.create(), r => r.order.ParentKey);
            case PTOC.FilledEvent: return _filled_event.create_predicate(data_cache);
            case PTOC.CompletedEvent: return _completed_event.create_predicate(data_cache);
            case PTOC.CanceledEvent: return _canceled_event.create(data_cache);
+            case PTOC.AttachedTargetOrderKey: return wrap(_attached_target_order_key, r => r.order.attached_target_order_key());
            default: return null;
         }
         //
-         IPredicate<OrderSecurity> wrap<T>(IPredicateBuilder<T> trigger, Func<OrderSecurity, T> select) =>
-            trigger.create(data_cache).wrap<OrderSecurity,T>(select);
+         IPredicate<OrderSecurity> wrap<T>(IPredicate<T> trigger, Func<OrderSecurity, T> select) =>
+            trigger.wrap<OrderSecurity, T>(select);
      }

-      IPredicate<OrderSecurity> IPredicateBuilder<OrderSecurity>.create(object obj) =>
-         create_predicate((INotificationServiceDataCache)obj);
-
      public INotificationPredicate<OrderSecurity> create_notification_predicate(INotificationServiceDataCache notification_service_data_cache) {
         if (!is_toast_enabled)
            return null;
@@ -252,9 +255,6 @@ namespace mbts {
         }
      }

-      INotificationPredicate<OrderSecurity> INotificationPredicateBuilder<OrderSecurity>.create_notification_predicate(object obj) =>
-         create_notification_predicate((INotificationServiceDataCache)obj);
-
      public bool Equals(OrderRecordTuplePredicate other) {
         if (other == null)
            return false;
@@ -285,6 +285,7 @@ namespace mbts {
            case PTOC.FilledEvent: return _filled_event.Equals(other._filled_event);
            case PTOC.CompletedEvent: return _completed_event.Equals(other._completed_event);
            case PTOC.CanceledEvent: return _canceled_event.Equals(other._canceled_event);
+            case PTOC.AttachedTargetOrderKey: return _attached_target_order_key.Equals(other._attached_target_order_key);
            case PTOC.None: return true;
            default: throw ExceptionHelper.unexpected_oneof_case(ptoc);
         }
@@ -319,6 +320,7 @@ namespace mbts {
            case PTOC.FilledEvent: raw_hash = _filled_event.GetHashCode(); break;
            case PTOC.CompletedEvent: raw_hash = _completed_event.GetHashCode(); break;
            case PTOC.CanceledEvent: raw_hash = _canceled_event.GetHashCode(); break;
+            case PTOC.AttachedTargetOrderKey: raw_hash = _attached_target_order_key.GetHashCode(); break;
            case PTOC.None: raw_hash = 0; break;
            default: throw ExceptionHelper.unexpected_oneof_case(ptoc);
         }
@@ -353,6 +355,7 @@ namespace mbts {
            _filled_event = null;
            _completed_event = null;
            _canceled_event = null;
+            _attached_target_order_key = null;
         }
         field = value;
      }
@@ -378,9 +381,9 @@ namespace mbts {
         _sound_animations = new List<SoundNotification> ( sound_animations );
      }

-      public OrderRecordTuplePredicate predicate_builder => _predicate;
+      public OrderRecordTuplePredicate predicate_data => _predicate;
      public IReadOnlyList<CellAnimation> cell_animations => _cell_animations ?? (_cell_animations = new List<CellAnimation>());
      public IReadOnlyList<RowAnimation> row_animations => _row_animations ?? (_row_animations = new List<RowAnimation>());
      public IReadOnlyList<SoundNotification> sound_notifications => _sound_animations ?? (_sound_animations = new List<SoundNotification>());
   }
-}
+}
@@ -1,7 +1,6 @@
 using bts.proto;
 using bts.utils;
 using mbts.spark;
-using mbts.spark.utilities;
 using mbts.ui.spark;
 using ProtoBuf;
 using System;
@@ -24,7 +23,7 @@ namespace mbts {
   }

   [ProtoContract]
-   class DoublePredicate : IPredicateBuilder<double>, IEquatable<DoublePredicate> {
+   class DoublePredicate : IEquatable<DoublePredicate> {
      // not using a 'negate' flag here bc its meaning is not consistent for all value-types
      // greater than vs less than for specific values, or inside vs outside for value-ranges
      // trading a little more code for more clarity
@@ -62,7 +61,7 @@ namespace mbts {
         }
      }

-      public IPredicate<double> create(object obj) {
+      public IPredicate<double> create() {
         switch (predicate_type_case) {
            case PredicateTypeOneofCase.GreaterThan: return PredicateBuilder.greater_than(_greater_than.Value);
            case PredicateTypeOneofCase.LessThan: return PredicateBuilder.less_than(_less_than.Value);
@@ -1,7 +1,6 @@
 using bts.api;
 using bts.utils;
 using mbts.spark;
-using mbts.spark.utilities;
 using mbts.ui.spark;
 using mbts.ui.utility;
 using ProtoBuf;
@@ -23,7 +22,7 @@ namespace mbts {
   }

   [ProtoContract]
-   class SidePredicate : IPredicateBuilder<Side>, IEquatable<SidePredicate> {
+   class SidePredicate : IEquatable<SidePredicate> {
      Side? _is_value;
      Side? _not_value;

@@ -48,7 +47,7 @@ namespace mbts {
         }
      }

-      public IPredicate<Side> create(object obj) {
+      public IPredicate<Side> create() {
         switch (predicate_type_case) {
            case PredicateTypeOneofCase.IsValue: return PredicateBuilder.equals(_is_value.Value);
            case PredicateTypeOneofCase.NotValue: return PredicateBuilder.not_equals(_not_value.Value);
@@ -1,9 +1,7 @@
 using bts.proto;
 using bts.utils;
 using mbts.spark;
-using mbts.spark.utilities;
 using mbts.ui.spark;
-using mbts.utils;
 using ProtoBuf;
 using System;
 using System.Collections.Generic;
@@ -27,7 +25,7 @@ namespace mbts {
   }

   [ProtoContract]
-   class StringPredicate : IPredicateBuilder<string>, IEquatable<StringPredicate> {
+   class StringPredicate : IEquatable<StringPredicate> {
      StringIgnoreCase? _is_string, _not_string, _contains_string, _not_contains_string;

      public enum PredicateTypeOneofCase {
@@ -61,7 +59,7 @@ namespace mbts {
         }
      }

-      public IPredicate<string> create(object obj) {
+      public IPredicate<string> create() {
         switch (predicate_type_case) {
            case PTOC.IsMatch: return PredicateBuilder.equals(_is_string.Value.text, _get_eq_comparer(_is_string));
            case PTOC.NotMatch: return PredicateBuilder.not_equals(_not_string.Value.text, _get_eq_comparer(_not_string));
@@ -1,7 +1,6 @@
 using bts.proto;
 using bts.utils;
 using mbts.spark;
-using mbts.spark.utilities;
 using mbts.ui.spark;
 using ProtoBuf;
 using System;
@@ -21,7 +20,7 @@ namespace mbts {
   }

   [ProtoContract]
-   class TimePredicate : IPredicateBuilder<DateTime>, IEquatable<TimePredicate> {
+   class TimePredicate : IEquatable<TimePredicate> {
      // not using a 'negate' flag here bc its meaning is not consistent for all value-types
      // before vs after for specific times, or inside vs outside for time-ranges
      // trading a little more code for clarity
@@ -59,7 +58,7 @@ namespace mbts {
         }
      }

-      public IPredicate<DateTime> create(object obj) {
+      public IPredicate<DateTime> create() {
         switch (predicate_type_case) {
            case PTOC.Before: return PredicateBuilder.less_than(_before.Value.get_date_time());
            case PTOC.After: return PredicateBuilder.greater_than(_after.Value.get_date_time());
@@ -1,7 +1,6 @@
 using bts.proto;
 using bts.utils;
 using mbts.spark;
-using mbts.spark.utilities;
 using mbts.ui.spark;
 using ProtoBuf;
 using System;
@@ -24,7 +23,7 @@ namespace mbts {
   }

   [ProtoContract]
-   class UIntPredicate : IPredicateBuilder<uint>, IEquatable<UIntPredicate> {
+   class UIntPredicate : IEquatable<UIntPredicate> {
      // not using a 'negate' flag here bc its meaning is not consistent for all value-types
      // greater than vs less than for specific values, or inside vs outside for value-ranges
      // trading a little more code for more clarity
@@ -62,7 +61,7 @@ namespace mbts {
         }
      }

-      public IPredicate<uint> create(object obj) {
+      public IPredicate<uint> create() {
         switch (predicate_type_case) {
            case PredicateTypeOneofCase.GreaterThan: return PredicateBuilder.greater_than(_greater_than.Value);
            case PredicateTypeOneofCase.LessThan: return PredicateBuilder.less_than(_less_than.Value);
@@ -1,7 +1,6 @@
 using bts.proto;
 using bts.utils;
 using mbts.spark;
-using mbts.spark.utilities;
 using mbts.ui.spark;
 using ProtoBuf;
 using System;
@@ -24,7 +23,7 @@ namespace mbts {
   }

   [ProtoContract]
-   class UShortPredicate : IPredicateBuilder<ushort>, IEquatable<UShortPredicate> {
+   class UShortPredicate : IEquatable<UShortPredicate> {
      // not using a 'negate' flag here bc its meaning is not consistent for all value-types
      // greater than vs less than for specific values, or inside vs outside for value-ranges
      // trading a little more code for more clarity
@@ -23,7 +23,7 @@ namespace mbts {
   }

   [ProtoContract]
-   class SecurityPredicate : IPredicateBuilder<SecurityImmutable>, IEquatable<SecurityPredicate> {
+   class SecurityPredicate : IEquatable<SecurityPredicate> {
      [ProtoMember(1)]
      SecurityCriteria _criteria;
      [ProtoMember(2)]
@@ -43,7 +43,8 @@ namespace mbts {
         _criteria == null ? PTOC.None :
            _negate ? PTOC.NotInCriteria : PTOC.InCriteria;

-      public IPredicate<SecurityImmutable> create(object obj) => _criteria.is_defined() ? new MyPredicate(_criteria, _negate) : null;
+      public IPredicate<SecurityImmutable> create() => _criteria.is_defined() ? new MyPredicate(_criteria, _negate) : null;
+
      public bool Equals(SecurityPredicate other) =>
         other != null &&
         _negate == other._negate &&
@@ -1,6 +1,4 @@
-using bts.shell;
-using bts.utils;
-using mbts.utils;
+using bts.utils;
 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
@@ -14,23 +12,6 @@ namespace mbts {
      bool trigger(T value);
   }

-   interface IPredicateBuilder<T> {
-      IPredicate<T> create(object obj);
-   }
-
-   interface INotificationPredicateBuilder<T> : IPredicateBuilder<T> {
-      bool is_toast_enabled { get; set; }
-      INotificationPredicate<T> create_notification_predicate(object obj);
-   }
-
-   interface IPredicateBuilder<T, TArg> : IPredicateBuilder<T> {
-      IPredicate<T> create_predicate(TArg arg);
-   }
-
-   interface INotificationPredicateBuilder<T, TArg> : IPredicateBuilder<T, TArg>, INotificationPredicateBuilder<T> {
-      INotificationPredicate<T> create_notification_predicate(TArg arg);
-   }
-
  public enum PredicateCategory {
      Normal,
      Event
@@ -13,25 +13,23 @@ using System.Reactive.Linq;
 using System.Windows.Data;

 namespace mbts.ui.settings {
-   interface IPredicateBuilderVM<TRowData, TPredicateBuilder, TPredicateBuilderOneof> : ITemplatedPropertyWrapperVM<TPredicateBuilder>
-      where TPredicateBuilder : IPredicateBuilder<TRowData>
-      where TPredicateBuilderOneof : struct {
-      IReadOnlyCollection<TPredicateBuilderOneof> predicate_types { get; }
+   interface IPredicateVM<TRowData, TPredicateData, TPredicateDataOneof> : ITemplatedPropertyWrapperVM<TPredicateData> where TPredicateDataOneof : struct {
+      IReadOnlyCollection<TPredicateDataOneof> predicate_types { get; }
      ICollectionView predicate_types_view { get; }
-      TPredicateBuilderOneof selected_predicate_type { get; set; }
-      ITemplatedPropertyWrapperVM<TPredicateBuilder> selected_predicate { get; }
+      TPredicateDataOneof selected_predicate_type { get; set; }
+      ITemplatedPropertyWrapperVM<TPredicateData> selected_predicate { get; }
      bool can_enable_toast_notifications { get; }
      bool toast_notifications_enabled { get; }
   }

-   interface IChildPredicateBuilderVM<TSource, TChildPredicateBuilder, TChildPredicateBuilderOneof> : ITemplatedPropertyWrapperVM<TSource> where TChildPredicateBuilderOneof : struct {
-      IReadOnlyCollection<TChildPredicateBuilderOneof> predicate_types { get; }
+   interface IChildPredicateVM<TSource, TChildPredicate, TChildPredicateOneof> : ITemplatedPropertyWrapperVM<TSource> where TChildPredicateOneof : struct {
+      IReadOnlyCollection<TChildPredicateOneof> predicate_types { get; }
      ICollectionView predicate_types_view { get; }
-      TChildPredicateBuilderOneof selected_predicate_type { get; set; }
-      ITemplatedPropertyWrapperVM<TChildPredicateBuilder> selected_predicate { get; }
+      TChildPredicateOneof selected_predicate_type { get; set; }
+      ITemplatedPropertyWrapperVM<TChildPredicate> selected_predicate { get; }
   }

-   static class PredicateBuilderVMWrapper {
+   static class PredicateVMWrapper {
      static readonly bool _toast_notifications_enabled_global = Configuration.get<bts.config.toggles.ToastNotifications>().enabled;

      public static ITemplatedPropertyWrapperVM<TSource> wrap_child_oneof<TSource, TChild, TChildOneof>(
@@ -39,14 +37,17 @@ namespace mbts.ui.settings {
         where TChildOneof : struct
         where TChild : new() =>
         //
-         new PredicateChildWrapperVM<TSource, TChild, TChildOneof>(get, set, get_child_oneof, oneof_vms);
+         new ChildImpl<TSource, TChild, TChildOneof>(get, set, get_child_oneof, oneof_vms);

-      public static IPredicateBuilderVM<TRowData, TPredicate, TPredicateOneof> create<TRowData, TPredicate, TPredicateOneof>(
-         Dictionary<TPredicateOneof, ITemplatedPropertyWrapperVM<TPredicate>> oneofs, Func<TPredicate, TPredicateOneof> key)
-         where TPredicateOneof : struct
-         where TPredicate : IPredicateBuilder<TRowData>, new() =>
+      public static IPredicateVM<TRowData, TPredicate, TPredicateOneof> create<TRowData, TPredicate, TPredicateOneof>(
+         Dictionary<TPredicateOneof, ITemplatedPropertyWrapperVM<TPredicate>> oneofs, Func<TPredicate, TPredicateOneof> key) where TPredicateOneof : struct =>
         //
-         new PredicateWrapperVM<TRowData, TPredicate, TPredicateOneof>(oneofs, key);
+         new Impl<TRowData, TPredicate, TPredicateOneof>(oneofs, key, _ => false, (p, b) => { });
+
+      public static IPredicateVM<TRowData, TPredicate, TPredicateOneof> create<TRowData, TPredicate, TPredicateOneof>(
+         Dictionary<TPredicateOneof, ITemplatedPropertyWrapperVM<TPredicate>> oneofs, Func<TPredicate, TPredicateOneof> key, Func<TPredicate, bool> get_is_toast_enabled, Action<TPredicate, bool> set_is_toast_enabled) where TPredicateOneof : struct =>
+         //
+         new Impl<TRowData, TPredicate, TPredicateOneof>(oneofs, key, get_is_toast_enabled, set_is_toast_enabled);

      public static ITemplatedPropertyWrapperVM<TSource> create<TSource>(Action<TSource> set = null) =>
         new PredicatePlaceholderVM<TSource>(set);
@@ -63,35 +64,30 @@ namespace mbts.ui.settings {
         return cv;
      }

-      class PredicateWrapperVM<TRowData, TPredicate, TPredicateOneof> : DisposableViewModelBase, IPredicateBuilderVM<TRowData, TPredicate, TPredicateOneof>, ITemplatedPropertyWrapperVM<TPredicate>
-         where TPredicateOneof : struct
-         where TPredicate : IPredicateBuilder<TRowData>, new() {
+      class Impl<TRowData, TPredicate, TPredicateOneof> : DisposableViewModelBase, IPredicateVM<TRowData, TPredicate, TPredicateOneof>, ITemplatedPropertyWrapperVM<TPredicate>
+         where TPredicateOneof : struct {
         readonly Dictionary<TPredicateOneof, ITemplatedPropertyWrapperVM<TPredicate>> _oneofs;
         readonly Property<TPredicateOneof> _selected_predicate_type;
         readonly Property<ITemplatedPropertyWrapperVM<TPredicate>> _selected_predicate;
         readonly DelegateProperty<bool> _can_enable_toast_notifications;
         readonly Property<bool> _toast_notifications_enabled;
         readonly Func<TPredicate, TPredicateOneof> _key_selector;
+         readonly Func<TPredicate, bool> _get_is_toast_enabled;
+         readonly Action<TPredicate, bool> _set_is_toast_enabeled;

-         public PredicateWrapperVM(Dictionary<TPredicateOneof, ITemplatedPropertyWrapperVM<TPredicate>> oneofs, Func<TPredicate, TPredicateOneof> key_selector) {
+         public Impl(Dictionary<TPredicateOneof, ITemplatedPropertyWrapperVM<TPredicate>> oneofs, Func<TPredicate, TPredicateOneof> key_selector, Func<TPredicate, bool> get_is_toast_enabled, Action<TPredicate, bool> set_is_toast_enabled) {
            _oneofs = oneofs;
            _key_selector = key_selector;
+            _get_is_toast_enabled = get_is_toast_enabled;
+            _set_is_toast_enabeled = set_is_toast_enabled;
            _selected_predicate = backing<ITemplatedPropertyWrapperVM<TPredicate>>(nameof(selected_predicate));
            _selected_predicate_type = backing<TPredicateOneof>(nameof(selected_predicate_type));
            predicate_types_view = _create_predicate_types_view(predicate_types);
-            if (typeof(TPredicate).GetInterfaces().Contains(typeof(INotificationPredicateBuilder<TRowData>))) {
-               // simple_predicates are only referred to when TPredicate is an INotificationPredicateBuilder, but does not support INotificationPredicates for every predicate-case
-               // (this way we can gradually add notifications as-needed beasis)
-               // for ex: we may release a cut that supports fill notifications without having to create a notification-predicate for every predicate-case in OrderRecordTuplePredicate.
-               // Note: it is assumed that all TPredicateOneof cases DO SUPPORT notification-predicates UNLESS THEY SPECIFY OTHERWISE IN A PREDICATECASEATTRIBUTE.
-               var simple_predicates = new HashSet<TPredicateOneof>(oneofs.Keys.Where(k => {
-                  var pca = EnumHelper.get_attribute<TPredicateOneof, PredicateCaseAttribute>(k);
-                  return pca != null && !pca.is_toastable;
-               }));
-               _can_enable_toast_notifications = backing(nameof(can_enable_toast_notifications), () => !simple_predicates.Contains(selected_predicate_type), nameof(selected_predicate_type));
-            } else {
-               _can_enable_toast_notifications = backing(nameof(can_enable_toast_notifications), () => false);
-            }
+            var toastable_predicates = new HashSet<TPredicateOneof>(oneofs.Keys.Where(k => {
+               var pca = EnumHelper.get_attribute<TPredicateOneof, PredicateCaseAttribute>(k);
+               return pca != null && pca.is_toastable;
+            }));
+            _can_enable_toast_notifications = backing(nameof(can_enable_toast_notifications), () => toastable_predicates.Contains(selected_predicate_type), nameof(selected_predicate_type));
            _toast_notifications_enabled = backing<bool>(nameof(toast_notifications_enabled));
            selected_predicate_type = predicate_types.FirstOrDefault();
         }
@@ -118,19 +114,18 @@ namespace mbts.ui.settings {
         public void load_from(TPredicate value) {
            selected_predicate_type = _key_selector(value);
            selected_predicate?.load_from(value);
-            if (can_enable_toast_notifications) {
-               _toast_notifications_enabled.set(((INotificationPredicateBuilder<TRowData>)value).is_toast_enabled);
-            }
+            if (can_enable_toast_notifications)
+               _toast_notifications_enabled.set(_get_is_toast_enabled(value));
         }

         public void assign_to(TPredicate value) {
            selected_predicate?.assign_to(value);
-            if (toast_notifications_enabled && value is INotificationPredicateBuilder<TRowData> tp)
-               tp.is_toast_enabled = true;
+            if (can_enable_toast_notifications)
+               _set_is_toast_enabeled(value, toast_notifications_enabled);
         }
      }

-      class PredicateChildWrapperVM<TPredicate, TChild, TChildKey> : DisposableViewModelBase, IChildPredicateBuilderVM<TPredicate, TChild, TChildKey> where TChildKey : struct where TChild : new() {
+      class ChildImpl<TPredicate, TChild, TChildKey> : DisposableViewModelBase, IChildPredicateVM<TPredicate, TChild, TChildKey> where TChildKey : struct where TChild : new() {
         readonly Property<ITemplatedPropertyWrapperVM<TChild>> _selected_predicate;
         readonly Property<TChildKey> _selected_predicate_type;
         readonly Dictionary<TChildKey, ITemplatedPropertyWrapperVM<TChild>> _children;
@@ -139,7 +134,7 @@ namespace mbts.ui.settings {
         readonly Func<TChild, TChildKey> _key;
         readonly string _template_key;

-         public PredicateChildWrapperVM(Func<TPredicate, TChild> get, Action<TPredicate, TChild> set, Func<TChild, TChildKey> key,
+         public ChildImpl(Func<TPredicate, TChild> get, Action<TPredicate, TChild> set, Func<TChild, TChildKey> key,
            Dictionary<TChildKey, ITemplatedPropertyWrapperVM<TChild>> oneofs, string template = PredicateTemplateKeys.Recursive) {
            _get = get;
            _set = set;
@@ -1,7 +1,10 @@
-<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
-                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-                    xmlns:mbts="clr-namespace:mbts.ui"
-                    xmlns:control="clr-namespace:mbts.ui.controls">
+<ResourceDictionary
+  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+  xmlns:bv="clr-namespace:bts.view"
+  xmlns:mbts="clr-namespace:mbts.ui"
+  xmlns:control="clr-namespace:mbts.ui.controls"
+>
  <ResourceDictionary.MergedDictionaries>
    <ResourceDictionary Source="/Images/Vector/Icons.xaml" />
    <ResourceDictionary Source="/view/Resources/Converters.xaml" />
@@ -516,9 +519,16 @@
      <Setter.Value>
        <DataTemplate>
          <control:SparkMenuItem
-            Content="{Binding title}" Command="{Binding command}" Style="{StaticResource SparkMenuButton}" Icon="{Binding icon}"
+            Command="{Binding command}" Style="{StaticResource SparkMenuButton}" Icon="{Binding icon}"
            Collapsed="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type control:SparkMenu}}, Path=ShowText, Converter={StaticResource NotConverter}}"
-          />
+          >
+            <control:SparkMenuItem.Content>
+              <MultiBinding Converter="{x:Static bv:SparkWindowView.HeaderConverter}">
+                <Binding Path="title"/>
+                <Binding Path="key_gesture"/>
+              </MultiBinding>
+            </control:SparkMenuItem.Content>
+          </control:SparkMenuItem>
        </DataTemplate>
      </Setter.Value>
    </Setter>
@@ -2,6 +2,7 @@
 using mbts;
 using mbts.ui;
 using System;
+using System.ComponentModel;
 using System.Linq;
 using System.Reactive.Linq;
 using System.Threading.Tasks;
@@ -11,13 +12,15 @@ using static mbts.spark.SparkTags;

 namespace bts.spark {
   public abstract class SparkCommand {
+      public readonly KeyGesture key_gesture;
      string _title;
      bool _show_in_toolbar, _show_in_context_menu;
-      public SparkCommand(string title, ImageSource icon, bool show_in_toolbar = true, bool show_in_context_menu = true) {
+      public SparkCommand(string title, ImageSource icon, bool show_in_toolbar = true, bool show_in_context_menu = true, KeyGesture key_gesture = null) {
         _title = title;
         this.icon = icon;
         _show_in_toolbar = show_in_toolbar;
         _show_in_context_menu = show_in_context_menu;
+         this.key_gesture = key_gesture;
      }

      public event Action title_changed, show_in_toolbar_changed, show_in_context_menu_changed;
@@ -78,11 +81,15 @@ namespace bts.spark {
      public static SparkCommandParamObserver<T> create<T>(string title, ImageSource icon, ITag<T> tag, IObservable<T> parameter, Func<T, bool> can_execute) =>
         create(title, icon, tag, parameter, parameter.Select(can_execute));

+      public static SparkCommandParamObserver<T> create<T>(string title, ImageSource icon, ITag<T> tag, IObservable<T> parameter, Func<T, bool> can_execute, Func<bool> is_confirmation_affirmed) =>
+         create(title, icon, tag, parameter, parameter.Select(can_execute), is_confirmation_affirmed);
+
      public static SparkCommandParamObserver<T> create<T, TSource>(string title, ImageSource icon, ITag<T> tag, IObservable<TSource> parameter_source, Func<TSource, bool> parameter_source_where, Func<TSource, T> parameter_selector) =>
         create(title, icon, tag, parameter_source.Select(parameter_selector), parameter_source.Select(parameter_source_where));

-      public static SparkCommandParamObserver<T> create<T>(string title, ImageSource icon, ITag<T> tag, IObservable<T> parameter, IObservable<bool> can_execute) =>
-         new SparkCommandParamObserver<T>(title, icon, tag, parameter, can_execute);
+      public static SparkCommandParamObserver<T> create<T>(string title, ImageSource icon, ITag<T> tag, IObservable<T> parameter, IObservable<bool> can_execute, Func<bool> is_confirmation_affirmed = null) =>
+         new SparkCommandParamObserver<T>(title, icon, tag, parameter, can_execute, is_confirmation_affirmed);
+
   }

   public static class SparkCommandExtensions {
@@ -132,11 +139,15 @@ namespace bts.spark {
      public SparkCommandParamObserver<T> complete(IObservable<T> value, Func<T, bool> can_execute) =>
         SparkCommand.create(title, icon, tag, value, can_execute);

+      public SparkCommandParamObserver<T> complete(IObservable<T> value, Func<T, bool> can_execute, Func<bool> is_confirmation_affirmed) =>
+         SparkCommand.create(title, icon, tag, value, can_execute, is_confirmation_affirmed);
+
      public SparkCommandParamObserver<T> complete<TSource>(IObservable<TSource> value_source, Func<TSource, bool> value_source_where, Func<TSource, T> value_selector) =>
         SparkCommand.create(title, icon, tag, value_source, value_source_where, value_selector);

      public SparkCommandParamObserver<T> complete(IObservable<T> parameter, IObservable<bool> can_execute) =>
         SparkCommand.create(title, icon, tag, parameter, can_execute);
+
   }

   public class SparkCommandWrapper : SparkCommand, IDisposable {
@@ -199,7 +210,8 @@ namespace bts.spark {
   public class SparkCommandCommand : SparkCommand {
      readonly ICommand _a;

-      public SparkCommandCommand(string title, ImageSource icon, ICommand a) : base(title, icon) {
+      public SparkCommandCommand(string title, ImageSource icon, ICommand a, KeyGesture key_gesture = null)
+         : base(title, icon, key_gesture: key_gesture) {
         _a = a;
      }

@@ -222,8 +234,9 @@ namespace bts.spark {
   }

   public class SparkCommandParamObserver<T> : SparkCommand, IDisposable {
-      public SparkCommandParamObserver(string title, ImageSource icon, ITag<T> tag, IObservable<T> parameter, IObservable<bool> can_execute) : base(title, icon) {
+      public SparkCommandParamObserver(string title, ImageSource icon, ITag<T> tag, IObservable<T> parameter, IObservable<bool> can_execute, Func<bool> is_confirmation_affirmed = null) : base(title, icon) {
         _tag = tag;
+         _is_confirmation_affirmed = is_confirmation_affirmed;
         _subs = Disposable.Create(
            parameter.OnDispatcher().Subscribe(p => _parameter = p),
            can_execute.OnDispatcher().Subscribe(ce => {
@@ -237,10 +250,12 @@ namespace bts.spark {
      IDisposable _subs;
      T _parameter;
      bool _can_execute;
+      Func<bool> _is_confirmation_affirmed;
+

      public override bool canExecute() => _can_execute;
      public override void execute(IBus bus) {
-         if (_can_execute) {
+         if (_can_execute && (_is_confirmation_affirmed == null || _is_confirmation_affirmed())) {
            try {
               bus.post(_tag, _parameter);
            } catch (Exception e) {
@@ -314,6 +329,7 @@ namespace bts.spark {
      }

      public string title => _cmd.title;
+      public KeyGesture key_gesture => _cmd.key_gesture;
      public ImageSource icon => _cmd.icon;
      public bool show_in_toolbar => _cmd.show_in_toolbar;
      public bool show_in_context_menu => _cmd.show_in_context_menu;
@@ -22,7 +22,7 @@ namespace mbts.spark
      public static ITag<IEnumerable<(OrderDefinitionImmutable definition, double price, uint size)>> RecreateOrder { get; } = new SparkTag<IEnumerable<(OrderDefinitionImmutable, double, uint)>>();

      public static ITag<IEnumerable<uint>> CancelOrders { get; } = new SparkTag<IEnumerable<uint>>();
-      public static ITag<IEnumerable<uint>> CrackOrders { get; } = new SparkTag<IEnumerable<uint>>();
+      public static ITag<IEnumerable<uint>> DetachOrders { get; } = new SparkTag<IEnumerable<uint>>();
      public static ITag<(uint key, double price, uint size)> UpdateOrder { get; } = new SparkTag<(uint, double, uint)>();

      public static ITag<uint> ShowModifyOrderTag { get; } = new SparkTag<uint>(nameof(ShowModifyOrderTag));
@@ -11,7 +11,7 @@ namespace mbts.ui.controls {
         var rv = new ObservableAggregateCollection<TInner>();
         var aggregator = new Aggregator<TInner>(rv);
         foreach (var o in source)
-            aggregator.add_collection(select_inner(o));
+            aggregator.Add(select_inner(o));
         source.CollectionChanged += _mk_outter_collection_changed_handler(aggregator, select_inner);
         return rv;
      }
@@ -20,7 +20,7 @@ namespace mbts.ui.controls {
         aggregate.Clear();
         var aggregator = new Aggregator<TInner>(aggregate);
         foreach (var o in source)
-            aggregator.add_collection(select_inner(o));
+            aggregator.Add(select_inner(o));
         var handler = _mk_outter_collection_changed_handler(aggregator, select_inner);
         source.CollectionChanged += handler;
         return Disposable.Create(() => source.CollectionChanged -= handler);
@@ -37,23 +37,23 @@ namespace mbts.ui.controls {
                  add_collections(e.NewStartingIndex, e.NewItems);
                  break;
               case NotifyCollectionChangedAction.Reset:
-                  aggregator.clear_collections();
+                  aggregator.Clear();
                  foreach (TOutter o in (IEnumerable<TOutter>)s)
-                     aggregator.add_collection(select_inner(o));
+                     aggregator.Add(select_inner(o));
                  break;
            }
         };
         void add_collections(int new_item_index, IList new_items) {
            foreach (TOutter o in new_items)
-               aggregator.insert_collection(new_item_index++, select_inner(o));
+               aggregator.Insert(new_item_index++, select_inner(o));
         }
         void remove_collections(int old_item_index, IList old_items) {
            foreach (TOutter o in old_items)
-               aggregator.remove_collection_at(old_item_index);
+               aggregator.RemoveAt(old_item_index);
         }
      }

-      internal class Aggregator<T> : IDisposable {
+      internal class Aggregator<T> : IDisposable, IList<ObservableCollection<T>>, IReadOnlyList<ObservableCollection<T>> {
         readonly ObservableCollection<T> _target;
         readonly List<ObservableCollection<T>> _collections = new List<ObservableCollection<T>>();
         bool _is_disposed;
@@ -61,28 +61,39 @@ namespace mbts.ui.controls {
         public Aggregator(ObservableCollection<T> target, params ObservableCollection<T>[] collections) {
            _target = target;
            foreach (var c in collections)
-               add_collection(c);
+               Add(c);
         }

-         public void add_collection(ObservableCollection<T> collection) {
+         public ObservableCollection<T> this[int index] {
+            get => _collections[index];
+            set => Insert(index, value);
+         }
+
+         public int Count => _collections.Count;
+
+         public bool IsReadOnly => false;
+
+         public void Add(ObservableCollection<T> collection) {
            _check_disposed();
            _target.AddRange(collection);
            _collections.Add(collection);
            collection.CollectionChanged += _on_collection_changed;
         }

-         public void remove_collection(ObservableCollection<T> collection) {
+         public bool Remove(ObservableCollection<T> collection) {
+            int num_before = _collections.Count;
            _check_disposed();
            _remove_collection_items(collection, out int _, out int collection_index);
            _collections.RemoveAt(collection_index);
            collection.CollectionChanged -= _on_collection_changed;
+            return _collections.Count < num_before;
         }

-         public void insert_collection(int index, ObservableCollection<T> collection) {
+         public void Insert(int index, ObservableCollection<T> collection) {
            _check_disposed();
            if (index < 0 || index > _collections.Count) throw new ArgumentOutOfRangeException(nameof(index));
            if (index == _collections.Count)
-               add_collection(collection);
+               Add(collection);
            else {
               _collections.Insert(index, collection);
               _on_collection_changed(collection, new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, collection, 0));
@@ -90,12 +101,12 @@ namespace mbts.ui.controls {
            }
         }

-         public void remove_collection_at(int index) {
+         public void RemoveAt(int index) {
            _check_disposed();
-            remove_collection(_collections[index]);
+            Remove(_collections[index]);
         }

-         public void clear_collections() {
+         public void Clear() {
            _check_disposed();
            foreach (var c in _collections)
               c.CollectionChanged -= _on_collection_changed;
@@ -103,6 +114,15 @@ namespace mbts.ui.controls {
            _target.Clear();
         }

+         public bool Contains(ObservableCollection<T> item) =>
+            _collections.Contains(item);
+
+         public void CopyTo(ObservableCollection<T>[] array, int arrayIndex) =>
+            _collections.CopyTo(array, arrayIndex);
+
+         public int IndexOf(ObservableCollection<T> item) =>
+            _collections.IndexOf(item);
+
         public void Dispose() {
            if (!_is_disposed) {
               foreach (var c in _collections)
@@ -111,6 +131,9 @@ namespace mbts.ui.controls {
            }
         }

+         public IEnumerator<ObservableCollection<T>> GetEnumerator() => _collections.GetEnumerator();
+         IEnumerator IEnumerable.GetEnumerator() => _collections.GetEnumerator();
+
         void _on_collection_changed(object sender, NotifyCollectionChangedEventArgs e) {
            _check_disposed();
            int offset = _get_collection_start(sender);
@@ -166,10 +189,12 @@ namespace mbts.ui.controls {
      public ObservableAggregateCollection(params ObservableCollection<T>[] collections) =>
         _aggregator = new ObservableAggregateCollection.Aggregator<T>(this, collections);

-      public void add_collection(ObservableCollection<T> collection) => _aggregator.add_collection(collection);
-      public void remove_collection(ObservableCollection<T> collection) => _aggregator.remove_collection(collection);
-      public void insert_collection(int index, ObservableCollection<T> collection) => _aggregator.insert_collection(index, collection);
-      public void remove_collection_at(int index) => _aggregator.remove_collection_at(index);
-      public void clear_collections() => _aggregator.clear_collections();
+      public IReadOnlyList<ObservableCollection<T>> source_collections => _aggregator;
+
+      public void add_collection(ObservableCollection<T> collection) => _aggregator.Add(collection);
+      public void remove_collection(ObservableCollection<T> collection) => _aggregator.Remove(collection);
+      public void insert_collection(int index, ObservableCollection<T> collection) => _aggregator.Insert(index, collection);
+      public void remove_collection_at(int index) => _aggregator.RemoveAt(index);
+      public void clear_collections() => _aggregator.Clear();
   }
 }
@@ -192,16 +192,16 @@ namespace mbts.ui.utility {
         }
      }

-      public static IDisposable connect_item_actions<T>(IReadOnlyObservableCollection<T> source, Action<T> action) {
-         foreach (T v in source)
-            action(v);
-         return source.Subscribe((s, e) => CollectionHelper.process_new_items(source, action, e));
-      }
+      public static IDisposable connect_item_actions<T>(IReadOnlyObservableCollection<T> source, Action<T> action) =>
+         connect_item_actions(source, source, action);

-      public static IDisposable connect_item_actions<T>(ObservableCollection<T> source, Action<T> action) {
-         foreach (T v in source)
+      public static IDisposable connect_item_actions<T>(ObservableCollection<T> source, Action<T> action) =>
+         connect_item_actions(source, source, action);
+
+      public static IDisposable connect_item_actions<T>(INotifyCollectionChanged notifier, IEnumerable<T> collection, Action<T> action) {
+         foreach (T v in collection)
            action(v);
-         return source.Subscribe((s, e) => CollectionHelper.process_new_items(source, action, e));
+         return notifier.Subscribe((s, e) => CollectionHelper.process_new_items(collection, action, e));
      }

      public static IDisposable connect_item_hooks<T>(IReadOnlyObservableCollection<T> source, Func<T, IDisposable> get_item_hook) {
@@ -218,6 +218,18 @@ namespace mbts.ui.utility {
            source.Subscribe((s, e) => CollectionHelper.reflect_change(item_hooks, source, get_item_hook, d => d.Dispose(), e)));
      }

+      public static IDisposable dispose_on_removed<T>(IReadOnlyObservableCollection<T> source) where T : IDisposable =>
+         connect_item_hooks(source, v => v);
+
+      public static IDisposable dispose_on_removed<T>(ObservableCollection<T> source, bool clear_source_on_dispose) where T : IDisposable =>
+         connect_item_hooks(source, v => v, clear_source_on_dispose);
+
+      public static IDisposable try_dispose_on_removed<T>(IReadOnlyObservableCollection<T> source) =>
+         connect_item_hooks(source, v => v as IDisposable ?? Disposable.empty);
+
+      public static IDisposable try_dispose_on_removed<T>(ObservableCollection<T> source, bool clear_source_on_dispose = false) =>
+         connect_item_hooks(source, v => v as IDisposable ?? Disposable.empty, clear_source_on_dispose);
+
      class SortedWrapper<T> : IReadOnlyObservableCollection<T> {
         const int _min_capacity = 4;
         readonly IComparer<T> _comparer;
@@ -27,7 +27,7 @@ namespace mbts.ui.utilities
         readonly IEqualityComparer<T> _comparer;
         readonly TSourceCollection _source;
         readonly IList<T> _target;
-         IDictionary<T, int> _cache = new Dictionary<T, int>();
+         IDictionary<T, int> _cache;
         IDisposable _sub;

         public DistinctCollectionResolver(TSourceCollection source, IList<T> target, Func<TSource, T> get_value)
@@ -38,6 +38,7 @@ namespace mbts.ui.utilities
            _target = target;
            _get_value = get_value;
            _comparer = comparer;
+            _cache = new Dictionary<T, int>(comparer);
            _sync();
            _sub = _source.Subscribe(_source_CollectionChanged);
         }
@@ -87,7 +87,11 @@ namespace mbts.ui.utility {
               foreach (var value in source_collection.OfType<INotifyPropertyChanged>())
                  value.PropertyChanged += on_item_PropertyChanged;
            }
-            CollectionHelper.sync_with_never_duplicate(filtered_collection, source_collection.Where(filter));
+            if (source_collection.Count == 0) {
+               filtered_collection.Clear();
+            } else {
+               CollectionHelper.sync_with_never_duplicate(filtered_collection, source_collection.Where(filter));
+            }
         }
      }
   }
@@ -213,4 +217,4 @@ namespace mbts.ui.utility {
         return i;
      }
   }
-}
+}
@@ -24,5 +24,8 @@ namespace mbts {
               return (uint)value;
         }
      }
+
+      public static double? nan_nullable(double value) =>
+         double.IsNaN(value) ? (double?)null : value;
   }
 }
@@ -54,6 +54,17 @@ namespace System.Collections.Generic {
      //   yield return item;
      //}

+      public static T SafeSingleOrDefault<T>(this IEnumerable<T> source) {
+         using (var en = source.GetEnumerator()) {
+            if (en.MoveNext()) {
+               var rv_candidate = en.Current;
+               if (!en.MoveNext())
+                  return rv_candidate;
+            }
+         }
+         return default;
+      }
+
      public static IEnumerable<T> TakeWhile<T, TAccumulate>(this IEnumerable<T> source, TAccumulate seed, Func<TAccumulate, T, TAccumulate> accumulate, Func<TAccumulate, T, bool> predicate) {
         TAccumulate a = seed;
         foreach (T el in source) {
@@ -86,6 +97,28 @@ namespace System.Collections.Generic {
         return false;
      }

+      public static bool TryGetSingle<T>(this IEnumerable<T> source, out T result) {
+         if (source == null) throw new ArgumentNullException(nameof(source));
+         using (var en = source.GetEnumerator()) {
+            if (en.MoveNext()) {
+               result = en.Current;
+               if (!en.MoveNext())
+                  return true;
+            }
+         }
+         result = default;
+         return false;
+      }
+
+      public static bool TryGetSingle<T, TResult>(this IEnumerable<T> source, Func<T, bool> predicate, Func<T, TResult> convert, out TResult result) {
+         if (TryGetSingle(source.Where(predicate), out T v)) {
+            result = convert(v);
+            return true;
+         }
+         result = default;
+         return false;
+      }
+
      public static T FirstOrDefault<T>(this IEnumerable<T> source, Func<T, bool> predicate, T default_rv) {
         if (source == null) throw new ArgumentNullException(nameof(source));
         foreach (T element in source)
@@ -1,25 +1,18 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Runtime.InteropServices;
-using System.Collections.ObjectModel;
-using System.Threading;
-using System.Reactive.Linq;
-using System.Collections;
-using mbts.utils;
-using System.Threading.Tasks;
+using bts;
 using mbts;
+using mbts.utils;
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Linq;
+using System.Reactive.Linq;
 using System.Reactive.Subjects;
+using System.Threading;
+using System.Threading.Tasks;
 using System.Windows.Threading;
-using System.Collections.Specialized;
-using mbts.spark;
-using bts.api;
-using bts;
-using bts.utils;

-namespace mbts
-{
+namespace mbts {
   public static class GlobalExtensions
   {
      #region AddRange
@@ -105,8 +98,8 @@ namespace mbts
         return items.GroupBy(key_selector).ToDictionary(g => g.Key, g => g.AsEnumerable());
      }

-	  public static IDictionary<K, V> MapAggregate<K, V, T>(this IEnumerable<T> items, Func<T, K> key_selector, Func<T, V> value_selector, V seed, Func<V, V, V> aggregate, IEqualityComparer<K> key_equality_comparer) {
-         return items.GroupBy(key_selector, key_equality_comparer).ToDictionary(g => g.Key, g => g.Select(value_selector).Aggregate(seed, aggregate));
+      public static IDictionary<K, V> MapAggregate<K, V, T>(this IEnumerable<T> items, Func<T, K> key_selector, Func<T, V> value_selector, V seed, Func<V, V, V> aggregate, IEqualityComparer<K> key_comparer) {
+         return items.GroupBy(key_selector, key_comparer).ToDictionary(g => g.Key, g => g.Select(value_selector).Aggregate(seed, aggregate), key_comparer);
      }

      public static int aggregate_hash<T>(this IEnumerable<T> series) where T : class {
@@ -238,8 +231,7 @@ namespace mbts
   }
 }

-namespace System.Collections.Specialized
-{
+namespace System.Collections.Specialized {
   public static class NotifyCollectionChangedExtensions
   {
      public static IDisposable SuspendHandler(this INotifyCollectionChanged source, NotifyCollectionChangedEventHandler handler) {
@@ -258,8 +250,7 @@ namespace System.Collections.Specialized
   }
 }

-namespace System.Reactive.Linq
-{
+namespace System.Reactive.Linq {
   public static class ObservableExtensions
   {
      /// <summary>
@@ -397,4 +388,4 @@ namespace System.Reactive.Linq
         };
      }
   }
-}
+}
@@ -1,4 +1,5 @@
-using mbts.ui.shell;
+using bts.utils;
+using mbts.ui.shell;
 using System;
 using System.Collections.Generic;
 using System.IO;
@@ -98,8 +99,12 @@ namespace mbts.ui {
         }
      }

-      public static string diagnostic_name(this IShellWindow window) =>
-         $"[{window.window_type}]{window.Title}";
+      public static string diagnostic_name(this IShellWindow window) {
+         var sb = new StringBuilderEx { "[", window.window_type, "]", window.Title };
+         if (window is ISharedWindow shared_win)
+            sb.Add("(thread: ", shared_win.thread_id, ")");
+         return sb.ToString();
+      }

      public static IObservable<string> observe_title(this IShellWindow window) {
         var src = Observable.FromEvent<Action, string>(cb => () => cb(window.Title), cb => window.TitleChanged += cb, cb => window.TitleChanged -= cb);
@@ -90,20 +90,25 @@ namespace mbts.utils {
      }

      // Note: this is not optimized, be wary of use with large collections
-      public static void sync_with_never_duplicate<T>(ObservableCollection<T> dest, IEnumerable<T> src) =>
+      public static void sync_with_never_duplicate<T>(IList<T> dest, IEnumerable<T> src) =>
         sync_with_never_duplicate(dest, src, EqualityComparer<T>.Default);

      // Note: this is not optimized, be wary of use with large collections
-      public static void sync_with_never_duplicate<T>(ObservableCollection<T> dest, IEnumerable<T> src, IEqualityComparer<T> comp) {
-         int i = 0;
-         foreach (var val in src.empty_if_null()) {
-            int curr_index = dest.IndexOf(val);
+      public static void sync_with_never_duplicate<T>(IList<T> dest, IEnumerable<T> src, IEqualityComparer<T> comp) {
+         var src_list = src as IList<T> ?? new List<T>(src);
+         var src_set = src as ISet<T> ?? new HashSet<T>(src_list);
+         for (int i = 0; i < dest.Count; i++) {
+            if (!src_set.Contains(dest[i]))
+               dest.RemoveAt(i);
+         }
+         for (int i = 0; i < src_list.Count; i++) {
+            int curr_index = dest.IndexOf(src_list[i]);
            if (curr_index == i) {
               continue;
-            } else if (curr_index > 0 && curr_index < dest.Count) {
+            } else if (curr_index >= 0 && curr_index < dest.Count) {
               dest.RemoveAt(curr_index);
            }
-            dest.Insert(i++, val);
+            dest.Insert(i, src_list[i]);
         }
      }

@@ -112,11 +117,16 @@ namespace mbts.utils {

      // Note: this is not optimized, be wary of use with large collections
      public static void sync_with_never_duplicate<T, TSource, TKey>(ObservableCollection<T> dest, IEnumerable<TSource> src, Func<TSource, T> create, Func<T, TKey> key_selector, Func<TSource, TKey> src_key_selector, IEqualityComparer<TKey> key_comparer) {
-         int i = 0;
-         var src_map = src.ToDictionary(src_key_selector);
+         var src_list = src as IList<TSource> ?? new List<TSource>(src);
+         var src_map = src_list.ToDictionary(src_key_selector);
+         for (int i = 0; i < dest.Count; i++) {
+            var k = key_selector(dest[i]);
+            if (!src_map.ContainsKey(k))
+               dest.RemoveAt(i);
+         }
         var dest_map = dest.ToDictionary(key_selector);
-         foreach (var val in src.empty_if_null()) {
-            TKey key = src_key_selector(val);
+         for (int i = 0; i < src_list.Count; i++) {
+            TKey key = src_key_selector(src_list[i]);
            if (dest_map.TryGetValue(key, out T dval)) {
               int curr_index = dest.IndexOf(dval);
               if (curr_index != i) {
@@ -124,9 +134,8 @@ namespace mbts.utils {
                  dest.Insert(i, dval);
               }
            } else {
-               dest.Insert(i, create(val));
+               dest.Insert(i, create(src_list[i]));
            }
-            ++i;
         }
      }

@@ -136,13 +145,5 @@ namespace mbts.utils {
            rv[i] = selector(source[i]);
         return rv;
      }
-
-      public static IDisposable dispose_on_removed<T>(ObservableCollection<T> collection) =>
-         collection.Subscribe((s, e) => {
-            if (e.OldItems != null) {
-               foreach (T item in e.OldItems)
-                  (item as IDisposable)?.Dispose();
-            }
-         });
   }
-}
+}
@@ -0,0 +1,162 @@
+using mbts.collections;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reactive.Disposables;
+using System.Reactive.Linq;
+using System.Threading.Tasks;
+
+namespace bts.utils {
+   class CommonValueMonitor<T> {
+      readonly RefCountMap<T> _values;
+      T _default_value;
+
+      public CommonValueMonitor()
+         : this(default, EqualityComparer<T>.Default) { }
+
+      public CommonValueMonitor(T default_value)
+         : this(default_value, EqualityComparer<T>.Default) { }
+
+      public CommonValueMonitor(T default_value, IEqualityComparer<T> comparer) {
+         _default_value = default_value;
+         _values = new RefCountMap<T>(comparer);
+      }
+
+      public event Action<T> common_value_changed;
+
+      public ICollection<T> distinct_values => _values.keys;
+      public T common_value => _values.keys.SafeSingleOrDefault();
+
+      public void add(T value) {
+         if (_values.increment_adds_key(value)) {
+            switch (_values.Count) {
+               case 1: common_value_changed?.Invoke(value); break;
+               case 2: common_value_changed?.Invoke(_default_value); break;
+            }
+         }
+      }
+
+      public void remove(T value) {
+         if (_values.decrement_removes_key(value)) {
+            switch (_values.Count) {
+               case 0: common_value_changed?.Invoke(_default_value); break;
+               case 1: common_value_changed?.Invoke(_values.keys.First()); break;
+            }
+         }
+      }
+   }
+
+   class CommonValueMonitorMultiplexor<TSource> {
+      int _member_id_counter;
+      readonly Dictionary<int, (Action<TSource> add, Action<TSource> remove)> _members = new Dictionary<int, (Action<TSource> add, Action<TSource> remove)>();
+
+      public void add(TSource value) {
+         foreach ((var add, var remove) in _members.Values)
+            add(value);
+      }
+
+      public void remove(TSource value) {
+         foreach ((var add, var remove) in _members.Values)
+            remove(value);
+      }
+
+      public IDisposable add_member_mon<T>(CommonValueMonitor<T> member_mon, Func<TSource, T> get_value) {
+         int id = _member_id_counter++;
+         _members.Add(id, (
+            v => member_mon.add(get_value(v)),
+            v => member_mon.remove(get_value(v))));
+         return Disposable.Create(() => _members.Remove(id));
+      }
+
+      public IDisposable add_member_mon<T>(CommonValueMonitor<T> member_mon, Func<TSource, T> get_value, Func<T, bool> where) {
+         int id = _member_id_counter++;
+         _members.Add(id, ( 
+            v => {
+               var res = get_value(v);
+               if (where(res))
+                  member_mon.add(res);
+            },
+            v => {
+               var res = get_value(v);
+               if (where(res))
+                  member_mon.remove(res);
+            }));
+         return Disposable.Create(() => _members.Remove(id));
+      }
+   }
+
+   static class CommonValueMonitorExtensions {
+      public static bool try_get_common_value<T>(this CommonValueMonitor<T> monitor, out T result) =>
+         monitor.distinct_values.TryGetSingle(out result);
+
+      public static T? common_value_nullable<T>(this CommonValueMonitor<T> monitor) where T : struct =>
+         monitor.try_get_common_value(out T result) ? result : (T?)null;
+
+      public static IObservable<T> SubscribeThrottled<T>(this CommonValueMonitor<T> monitor, TimeSpan throttle) =>
+         Observable.Create<T>(o => {
+            bool busy = false, dirty = false;
+            o.OnNext(monitor.common_value);
+            monitor.common_value_changed += on_changed;
+            return Disposable.Create(() => monitor.common_value_changed -= on_changed);
+            async void on_changed(T _) {
+               if (busy) {
+                  dirty = true;
+                  return;
+               }
+               dirty = false;
+               do {
+                  o.OnNext(monitor.common_value);
+                  await Task.Delay(throttle);
+               } while (dirty);
+               busy = false;
+            }
+         });
+
+      public static IObservable<T> SubscribeThrottled<T>(this CommonValueMonitor<T> monitor, TimeSpan throttle, T default_value) =>
+         Observable.Create<T>(o => {
+            bool busy = false, dirty = false;
+            notify();
+            monitor.common_value_changed += on_changed;
+            return Disposable.Create(() => monitor.common_value_changed -= on_changed);
+            async void on_changed(T _) {
+               if (busy) {
+                  dirty = true;
+                  return;
+               }
+               dirty = false;
+               do {
+                  notify();
+                  await Task.Delay(throttle);
+               } while (dirty);
+               busy = false;
+            }
+            void notify() =>
+               o.OnNext(monitor.try_get_common_value(out T result) ? result : default_value);
+         });
+
+      public static IObservable<TResult> SubscribeThrottled<T, TResult>(this CommonValueMonitor<T> monitor, TimeSpan throttle, Func<T, TResult> selector, TResult default_value) =>
+         Observable.Create<TResult>(o => {
+            bool busy = false, dirty = false;
+            notify();
+            monitor.common_value_changed += on_changed;
+            return Disposable.Create(() => monitor.common_value_changed -= on_changed);
+            async void on_changed(T _) {
+               if (busy) {
+                  dirty = true;
+                  return;
+               }
+               dirty = false;
+               do {
+                  notify();
+                  await Task.Delay(throttle);
+               } while (dirty);
+               busy = false;
+            }
+            void notify() =>
+               o.OnNext(monitor.try_get_common_value(out T result) ? selector(result) : default_value);
+       });
+
+      public static IObservable<T?> SubscribeThrottledNullable<T>(this CommonValueMonitor<T> monitor, TimeSpan throttle) where T : struct =>
+         monitor.SubscribeThrottled<T, T?>(throttle, val => val, null);
+   }
+}
@@ -0,0 +1,49 @@
+using mbts.ui.shell;
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace bts.utils {
+   class PropertyUpdateThrottle<T> {
+      readonly TimeSpan _throttle;
+      readonly IEqualityComparer<T> _comparer;
+      bool _busy, _dirty;
+      T _value, _last_fired;
+
+      public PropertyUpdateThrottle(TimeSpan throttle)
+         : this(throttle, EqualityComparer<T>.Default) { }
+
+      public PropertyUpdateThrottle(TimeSpan throttle, IEqualityComparer<T> comparer) {
+         _throttle = throttle;
+         _comparer = comparer;
+      }
+
+      public T value {
+         get => _value;
+         set {
+            if (!_comparer.Equals(_value, value)) {
+               _value = value;
+               _fire();
+            }
+         }
+      }
+
+      public event PropertyChange<T> changed;
+
+      async void _fire() {
+         if (!_busy) {
+            _busy = true;
+            do {
+               var old = _last_fired;
+               _last_fired = _value;
+               changed?.Invoke(old, _value);
+               _dirty = false;
+               await Task.Delay(_throttle);
+            } while (_dirty);
+            _busy = false;
+         } else {
+            _dirty = true;
+         }
+      }
+   }
+}
@@ -1,91 +1,115 @@
-using mbts;
-using Google.Protobuf;
-using Google.Protobuf.Reflection;
-using mbts.ui.utility;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using mbts.utils;
-
-namespace bts.utils {
-   static class ProtoHelper {
-      const string
-         _case_suffix = "Case",
-         _oneof_case_suffix = "OneofCase";
-
-      public static MessageDescriptor Descriptor<T>() where T : IMessage, new() =>
-         _DescriptorImpl<T>.value;
-
-      public static OneofDescriptor get_oneof_descriptor<T>(string prop_name) where T : IMessage, new() {
-         prop_name = prop_name.iremove_suffix(_case_suffix);
-         return Descriptor<T>().Oneofs.FirstOrDefault(d => d.Name.iequals(prop_name));
-      }
-
-      public static IReadOnlyDictionary<TOneofCase, (FieldDescriptor field_descriptor, Type field_type)> get_oneof_descriptor_index<T, TOneofCase>(string prop_name)
-         where T : IMessage, new()
-         where TOneofCase : struct =>
-         _DescriptorImpl<T>.OneofImpl<TOneofCase>.get_descriptor_case_index(prop_name);
-
-      public static FieldDescriptor get_oneof_field_descriptor<T, TOneofCase>(TOneofCase oneof_case) where T : IMessage, new() where TOneofCase : struct {
-         string oneof_name = oneof_case.ToString();
-         return Descriptor<T>().Fields.InFieldNumberOrder().FirstOrDefault(fd => fd.Name.Replace("_", "").iequals(oneof_name));
-      }
-
-      public static Type get_field_type(FieldDescriptor field_descriptor) {
-         switch (field_descriptor.FieldType) {
-            case FieldType.Bool: return typeof(bool);
-            case FieldType.Bytes: return typeof(ByteString);
-            case FieldType.Double: return typeof(double);
-            case FieldType.Float: return typeof(float);
-            case FieldType.UInt32: return typeof(uint);
-            case FieldType.UInt64: return typeof(ulong);
-            // int
-            case FieldType.SFixed32:
-            case FieldType.Fixed32:
-            case FieldType.SInt32:
-            case FieldType.Int32: return typeof(int);
-            // long
-            case FieldType.SFixed64:
-            case FieldType.Fixed64:
-            case FieldType.SInt64:
-            case FieldType.Int64: return typeof(long);
-            //
-            case FieldType.String: return typeof(string);
-            case FieldType.Enum: return field_descriptor.EnumType.ClrType;
-            case FieldType.Message: return field_descriptor.MessageType.ClrType;
-            default: throw ExceptionBuilder.Argument.unexpected_case(field_descriptor.FieldType, nameof(field_descriptor));
-         }
-      }
-
-      public static IReadOnlyDictionary<TOneofCase, FieldDescriptor> get_oneof_descriptor_index<TOneofCase>(OneofDescriptor descriptor) where TOneofCase : struct =>
-         descriptor.Fields.ToDictionary(fd => EnumHelper.parse<TOneofCase>(fd.Name.Replace("_", "")));
-
-      static class _DescriptorImpl<T> where T : IMessage, new() {
-         public static readonly MessageDescriptor value = new T().Descriptor;
-
-         public static class OneofImpl<TOneofCase> where TOneofCase : struct {
-            static Dictionary<string, IReadOnlyDictionary<TOneofCase, (FieldDescriptor field_descriptor, Type field_type)>> _descriptor_case_indices =
-               new Dictionary<string, IReadOnlyDictionary<TOneofCase, (FieldDescriptor field_descriptor, Type field_type)>>();
-
-            public static IReadOnlyDictionary<TOneofCase, (FieldDescriptor field_descriptor, Type field_type)> get_descriptor_case_index(string prop_name) {
-               /// Use local copy because <see cref="_descriptor_case_indices"/> is updated atomically.
-               var dci = _descriptor_case_indices;
-               if (!dci.TryGetValue(prop_name, out IReadOnlyDictionary<TOneofCase, (FieldDescriptor field_descriptor, Type field_type)> rv)) {
-                  /// Update <see cref="_descriptor_case_indices"/> atomically (lock-free).
-                  ///   1) clone the local copy.
-                  ///   2) add the new KeyValue to the clone.
-                  ///   3) assign the clone back to <see cref="_descriptor_case_indices"/>.
-                  rv = get_oneof_descriptor_index<TOneofCase>(get_oneof_descriptor<T>(prop_name))
-                     .ToDictionary(kv => kv.Key, kv => (kv.Value, get_field_type(kv.Value)));
-                  dci = dci.ToDictionary();
-                  dci.Add(prop_name, rv);
-                  /// It is possible for add ops to be overwritten.
-                  /// This is perfectly safe, just means that the 'clone-add-assign' will be repeated the next time a caller requests this key.
-                  _descriptor_case_indices = dci;
-               }
-               return rv;
-            }
-         }
-      }
-   }
-}
+using mbts;
+using Google.Protobuf;
+using Google.Protobuf.Reflection;
+using mbts.ui.utility;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using mbts.utils;
+using bts.api;
+using bts.api.orderman;
+using System.Reflection;
+
+namespace bts.utils {
+   static class ProtoHelper {
+      const string
+         _case_suffix = "Case",
+         _oneof_case_suffix = "OneofCase";
+
+      public static MessageDescriptor Descriptor<T>() where T : IMessage, new() =>
+         _DescriptorImpl<T>.value;
+
+      public static OneofDescriptor get_oneof_descriptor<T>(string prop_name) where T : IMessage, new() {
+         prop_name = prop_name.iremove_suffix(_case_suffix);
+         return Descriptor<T>().Oneofs.FirstOrDefault(d => d.Name.iequals(prop_name));
+      }
+
+      public static IReadOnlyDictionary<TOneofCase, (FieldDescriptor field_descriptor, Type field_type)> get_oneof_descriptor_index<T, TOneofCase>(string prop_name)
+         where T : IMessage, new()
+         where TOneofCase : struct =>
+         _DescriptorImpl<T>.OneofImpl<TOneofCase>.get_descriptor_case_index(prop_name);
+
+      public static FieldDescriptor get_oneof_field_descriptor<T, TOneofCase>(TOneofCase oneof_case) where T : IMessage, new() where TOneofCase : struct {
+         string oneof_name = oneof_case.ToString();
+         return Descriptor<T>().Fields.InFieldNumberOrder().FirstOrDefault(fd => fd.Name.Replace("_", "").iequals(oneof_name));
+      }
+
+      public static TImmutable immutable_factory<TMutable, TImmutable>(TMutable m) where TMutable : IMessage, new() where TImmutable : IImmutableMessage =>
+         (TImmutable)Activator.CreateInstance(typeof(TImmutable), m);
+
+      public static IMessage mutable_factory(Type type) =>
+         MutableFactoryStore.get(type)();
+
+      static class MutableFactoryStore {
+         [ThreadStatic]
+         static readonly Dictionary<Type, Func<IMessage>> _factories = new Dictionary<Type, Func<IMessage>>();
+
+         public static Func<IMessage> get(Type type) =>
+            _factories.GetOrAdd(type,
+               t => typeof(MutableFactory<>).MakeGenericType(t)
+               .GetField(nameof(MutableFactory<LimitOrderDefinition>.anonymous_factory), BindingFlags.Static | BindingFlags.Public)
+               .GetValue(null) as Func<IMessage>);
+      }
+
+      static class MutableFactory<T> where T : IMessage<T>, new() {
+         public static readonly Func<IMessage> anonymous_factory = () => new T();
+      }
+
+      public static Type get_field_type(FieldDescriptor field_descriptor) {
+         switch (field_descriptor.FieldType) {
+            case FieldType.Bool: return typeof(bool);
+            case FieldType.Bytes: return typeof(ByteString);
+            case FieldType.Double: return typeof(double);
+            case FieldType.Float: return typeof(float);
+            case FieldType.UInt32: return typeof(uint);
+            case FieldType.UInt64: return typeof(ulong);
+            // int
+            case FieldType.SFixed32:
+            case FieldType.Fixed32:
+            case FieldType.SInt32:
+            case FieldType.Int32: return typeof(int);
+            // long
+            case FieldType.SFixed64:
+            case FieldType.Fixed64:
+            case FieldType.SInt64:
+            case FieldType.Int64: return typeof(long);
+            //
+            case FieldType.String: return typeof(string);
+            case FieldType.Enum: return field_descriptor.EnumType.ClrType;
+            case FieldType.Message: return field_descriptor.MessageType.ClrType;
+            default: throw ExceptionBuilder.Argument.unexpected_case(field_descriptor.FieldType, nameof(field_descriptor));
+         }
+      }
+
+      public static IReadOnlyDictionary<TOneofCase, FieldDescriptor> get_oneof_descriptor_index<TOneofCase>(OneofDescriptor descriptor) where TOneofCase : struct =>
+         descriptor.Fields.ToDictionary(fd => EnumHelper.parse<TOneofCase>(fd.Name.Replace("_", "")));
+
+      static class _DescriptorImpl<T> where T : IMessage, new() {
+         public static readonly MessageDescriptor value = new T().Descriptor;
+
+         public static class OneofImpl<TOneofCase> where TOneofCase : struct {
+            static Dictionary<string, IReadOnlyDictionary<TOneofCase, (FieldDescriptor field_descriptor, Type field_type)>> _descriptor_case_indices =
+               new Dictionary<string, IReadOnlyDictionary<TOneofCase, (FieldDescriptor field_descriptor, Type field_type)>>();
+
+            public static IReadOnlyDictionary<TOneofCase, (FieldDescriptor field_descriptor, Type field_type)> get_descriptor_case_index(string prop_name) {
+               /// Use local copy because <see cref="_descriptor_case_indices"/> is updated atomically.
+               var dci = _descriptor_case_indices;
+               if (!dci.TryGetValue(prop_name, out IReadOnlyDictionary<TOneofCase, (FieldDescriptor field_descriptor, Type field_type)> rv)) {
+                  /// Update <see cref="_descriptor_case_indices"/> atomically (lock-free).
+                  ///   1) clone the local copy.
+                  ///   2) add the new KeyValue to the clone.
+                  ///   3) assign the clone back to <see cref="_descriptor_case_indices"/>.
+                  rv = get_oneof_descriptor_index<TOneofCase>(get_oneof_descriptor<T>(prop_name))
+                     .ToDictionary(kv => kv.Key, kv => (kv.Value, get_field_type(kv.Value)));
+                  dci = dci.ToDictionary();
+                  dci.Add(prop_name, rv);
+                  /// It is possible for add ops to be overwritten.
+                  /// This is perfectly safe, just means that the 'clone-add-assign' will be repeated the next time a caller requests this key.
+                  _descriptor_case_indices = dci;
+               }
+               return rv;
+            }
+         }
+      }
+   }
+}
@@ -4,8 +4,11 @@
  xmlns:mbts="clr-namespace:mbts.ui"
  xmlns:ui="clr-namespace:mbts.ui"
 >
+  <!--Control Base Colors-->
+  <Color x:Key="Control.MediumGrayColor">#B3B3B3</Color>
  <Color x:Key="Text.Prompt.Foreground.Color">#FF999999</Color>

+  <SolidColorBrush x:Key="Control.MediumGrayBrush" Color="{StaticResource Control.MediumGrayColor}"/>
  <SolidColorBrush x:Key="CommonBackground" Color="{ui:BTSColor common_background}" />
  <SolidColorBrush x:Key="ControlBackground" Color="{x:Static mbts:BTSColors.common_background}" />
  <SolidColorBrush x:Key="AccentColor1" Color="{x:Static mbts:BTSColors.accent1}" />
@@ -49,48 +52,48 @@
  <SolidColorBrush x:Key="CheckBox.Pressed.BorderBrush" Color="{StaticResource CheckBox.Pressed.BorderColor}"/>

  <!--ComboBox-->
-  <LinearGradientBrush x:Key="ComboBox.Static.Background" EndPoint="0,1" StartPoint="0,0">
-    <GradientStop Color="#FFF0F0F0" Offset="0.0"/>
-    <GradientStop Color="#FFE5E5E5" Offset="1.0"/>
-  </LinearGradientBrush>
-  <SolidColorBrush x:Key="ComboBox.Static.Border" Color="#FFACACAC"/>
-  <SolidColorBrush x:Key="ComboBox.Static.Editable.Background" Color="#FFFFFFFF"/>
-  <SolidColorBrush x:Key="ComboBox.Static.Editable.Border" Color="#FFABADB3"/>
-  <SolidColorBrush x:Key="ComboBox.Static.Editable.Button.Background" Color="Transparent"/>
-  <SolidColorBrush x:Key="ComboBox.Static.Editable.Button.Border" Color="Transparent"/>
-  <SolidColorBrush x:Key="ComboBox.MouseOver.Glyph" Color="#FF000000"/>
-  <LinearGradientBrush x:Key="ComboBox.MouseOver.Background" EndPoint="0,1" StartPoint="0,0">
-    <GradientStop Color="#FFECF4FC" Offset="0.0"/>
-    <GradientStop Color="#FFDCECFC" Offset="1.0"/>
-  </LinearGradientBrush>
-  <SolidColorBrush x:Key="ComboBox.MouseOver.Border" Color="#FF7EB4EA"/>
-  <SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Background" Color="#FFFFFFFF"/>
-  <SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Border" Color="#FF7EB4EA"/>
-  <LinearGradientBrush x:Key="ComboBox.MouseOver.Editable.Button.Background" EndPoint="0,1" StartPoint="0,0">
-    <GradientStop Color="#FFEBF4FC" Offset="0.0"/>
-    <GradientStop Color="#FFDCECFC" Offset="1.0"/>
-  </LinearGradientBrush>
-  <SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Button.Border" Color="#FF7EB4EA"/>
-  <SolidColorBrush x:Key="ComboBox.Pressed.Glyph" Color="#FF000000"/>
-  <LinearGradientBrush x:Key="ComboBox.Pressed.Background" EndPoint="0,1" StartPoint="0,0">
-    <GradientStop Color="#FFDAECFC" Offset="0.0"/>
-    <GradientStop Color="#FFC4E0FC" Offset="1.0"/>
-  </LinearGradientBrush>
-  <SolidColorBrush x:Key="ComboBox.Pressed.Border" Color="#FF569DE5"/>
-  <SolidColorBrush x:Key="ComboBox.Pressed.Editable.Background" Color="#FFFFFFFF"/>
-  <SolidColorBrush x:Key="ComboBox.Pressed.Editable.Border" Color="#FF569DE5"/>
-  <LinearGradientBrush x:Key="ComboBox.Pressed.Editable.Button.Background" EndPoint="0,1" StartPoint="0,0">
-    <GradientStop Color="#FFDAEBFC" Offset="0.0"/>
-    <GradientStop Color="#FFC4E0FC" Offset="1.0"/>
-  </LinearGradientBrush>
-  <SolidColorBrush x:Key="ComboBox.Pressed.Editable.Button.Border" Color="#FF569DE5"/>
-  <SolidColorBrush x:Key="ComboBox.Disabled.Glyph" Color="#FFBFBFBF"/>
-  <SolidColorBrush x:Key="ComboBox.Disabled.Background" Color="#FFF0F0F0"/>
-  <SolidColorBrush x:Key="ComboBox.Disabled.Border" Color="#FFD9D9D9"/>
-  <SolidColorBrush x:Key="ComboBox.Disabled.Editable.Background" Color="#FFFFFFFF"/>
-  <SolidColorBrush x:Key="ComboBox.Disabled.Editable.Border" Color="#FFBFBFBF"/>
-  <SolidColorBrush x:Key="ComboBox.Disabled.Editable.Button.Background" Color="Transparent"/>
-  <SolidColorBrush x:Key="ComboBox.Disabled.Editable.Button.Border" Color="Transparent"/>
+  <LinearGradientBrush x:Key="ComboBox.Static.Background" EndPoint="0,1" StartPoint="0,0">
+    <GradientStop Color="#FFF0F0F0" Offset="0.0"/>
+    <GradientStop Color="#FFE5E5E5" Offset="1.0"/>
+  </LinearGradientBrush>
+  <SolidColorBrush x:Key="ComboBox.Static.Border" Color="#FFACACAC"/>
+  <SolidColorBrush x:Key="ComboBox.Static.Editable.Background" Color="#FFFFFFFF"/>
+  <SolidColorBrush x:Key="ComboBox.Static.Editable.Border" Color="#FFABADB3"/>
+  <SolidColorBrush x:Key="ComboBox.Static.Editable.Button.Background" Color="Transparent"/>
+  <SolidColorBrush x:Key="ComboBox.Static.Editable.Button.Border" Color="Transparent"/>
+  <SolidColorBrush x:Key="ComboBox.MouseOver.Glyph" Color="#FF000000"/>
+  <LinearGradientBrush x:Key="ComboBox.MouseOver.Background" EndPoint="0,1" StartPoint="0,0">
+    <GradientStop Color="#FFECF4FC" Offset="0.0"/>
+    <GradientStop Color="#FFDCECFC" Offset="1.0"/>
+  </LinearGradientBrush>
+  <SolidColorBrush x:Key="ComboBox.MouseOver.Border" Color="#FF7EB4EA"/>
+  <SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Background" Color="#FFFFFFFF"/>
+  <SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Border" Color="#FF7EB4EA"/>
+  <LinearGradientBrush x:Key="ComboBox.MouseOver.Editable.Button.Background" EndPoint="0,1" StartPoint="0,0">
+    <GradientStop Color="#FFEBF4FC" Offset="0.0"/>
+    <GradientStop Color="#FFDCECFC" Offset="1.0"/>
+  </LinearGradientBrush>
+  <SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Button.Border" Color="#FF7EB4EA"/>
+  <SolidColorBrush x:Key="ComboBox.Pressed.Glyph" Color="#FF000000"/>
+  <LinearGradientBrush x:Key="ComboBox.Pressed.Background" EndPoint="0,1" StartPoint="0,0">
+    <GradientStop Color="#FFDAECFC" Offset="0.0"/>
+    <GradientStop Color="#FFC4E0FC" Offset="1.0"/>
+  </LinearGradientBrush>
+  <SolidColorBrush x:Key="ComboBox.Pressed.Border" Color="#FF569DE5"/>
+  <SolidColorBrush x:Key="ComboBox.Pressed.Editable.Background" Color="#FFFFFFFF"/>
+  <SolidColorBrush x:Key="ComboBox.Pressed.Editable.Border" Color="#FF569DE5"/>
+  <LinearGradientBrush x:Key="ComboBox.Pressed.Editable.Button.Background" EndPoint="0,1" StartPoint="0,0">
+    <GradientStop Color="#FFDAEBFC" Offset="0.0"/>
+    <GradientStop Color="#FFC4E0FC" Offset="1.0"/>
+  </LinearGradientBrush>
+  <SolidColorBrush x:Key="ComboBox.Pressed.Editable.Button.Border" Color="#FF569DE5"/>
+  <SolidColorBrush x:Key="ComboBox.Disabled.Glyph" Color="#FFBFBFBF"/>
+  <SolidColorBrush x:Key="ComboBox.Disabled.Background" Color="#FFF0F0F0"/>
+  <SolidColorBrush x:Key="ComboBox.Disabled.Border" Color="#FFD9D9D9"/>
+  <SolidColorBrush x:Key="ComboBox.Disabled.Editable.Background" Color="#FFFFFFFF"/>
+  <SolidColorBrush x:Key="ComboBox.Disabled.Editable.Border" Color="#FFBFBFBF"/>
+  <SolidColorBrush x:Key="ComboBox.Disabled.Editable.Button.Background" Color="Transparent"/>
+  <SolidColorBrush x:Key="ComboBox.Disabled.Editable.Button.Border" Color="Transparent"/>
  <SolidColorBrush x:Key="ComboBox.Static.Glyph" Color="#FF606060"/>

  <!--ListBox-->
@@ -0,0 +1,11 @@
+using System.Windows;
+using System.Windows.Documents;
+
+namespace mbts.ui.controls.adorners {
+   class Adorner<T> : Adorner where T : UIElement {
+      public Adorner(T adorned_element) : base(adorned_element) =>
+         AdornedElement = adorned_element;
+
+      public new T AdornedElement { get; }
+   }
+}