/*
* Copyright Onix Solutions Limited [OnixS]. All rights reserved.
*
* This software owned by Onix Solutions Limited [OnixS] and is protected by copyright law
* and international copyright treaties.
*
* Access to and use of the software is governed by the terms of the applicable OnixS Software
* Services Agreement (the Agreement) and Customer end user license agreements granting
* a non-assignable, non-transferable and non-exclusive license to use the software
* for it's own data processing purposes under the terms defined in the Agreement.
*
* Except as otherwise granted within the terms of the Agreement, copying or reproduction of any part
* of this source code or associated reference material to any other location for further reproduction
* or redistribution, and any amendments to this copyright notice, are expressly prohibited.
*
* Any reproduction or redistribution for sale or hiring of the Software not in accordance with
* the terms of the Agreement is a violation of copyright law.
*/

#pragma once

#include <OnixS/FIXEngine/ABI.h>

#include <string>
#include <stdexcept>
#include <iosfwd>

namespace OnixS {
namespace FIX {
typedef char Char;

typedef short int Int16;
typedef short unsigned int UInt16;

typedef int Int32;
typedef unsigned int UInt32;

typedef long long Int64;
typedef unsigned long long UInt64;

typedef double Double;

typedef Int64 DecimalMantissa;
typedef Int32 DecimalExponent;

/// The Decimal type for a better precision.
class ONIXS_FIXENGINE_API Decimal
{
public:
    /// Initializes an instance from compound components.
    Decimal(
        DecimalMantissa mantissa = 0,
        DecimalExponent exponent = 0);

    /// Converts the Double value to a decimal.
    /// @param value The double precision floating-point value.
    /// @param precision Defines the conversion precision.
    explicit Decimal(Double value, size_t precision = 17);

    /// Returns the mantissa part of the decimal.
    DecimalMantissa mantissa() const;

    /// Updates the mantissa part of the decimal.
    void mantissa(DecimalMantissa);

    /// Returns the exponent part of the decimal.
    DecimalExponent exponent() const;

    /// Updates the exponent part of the decimal.
    void exponent(DecimalExponent);

    /// Compares two numbers.
    bool operator == (const Decimal &) const;

    /// Compares two numbers.
    bool operator != (const Decimal &) const;

    /// Compares two numbers.
    bool operator < (const Decimal &) const;

    /// Compares two numbers.
    bool operator > (const Decimal &) const;

    /// Casts to the whole integer number as a regular
    /// floating point value is casted.
    /// @throw The domain_error exception on a failure.
    operator Int32() const;

    /// Casts to the whole integer number as a regular
    /// floating point value is casted.
    /// @throw The domain_error exception on a failure.
    operator UInt32() const;

    /// Casts to the whole integer number as a regular
    /// floating point value is casted.
    /// @throw The domain_error exception on a failure.
    operator Int64() const;

    /// Casts to the whole integer number as a regular
    /// floating point value is casted.
    /// @throw The domain_error exception on a failure.
    operator UInt64() const;

    /// Casts to the whole integer number as a regular
    /// floating point value is casted.
    /// @throw The domain_error exception on a failure.
    operator Double() const;

    /// Casts to the whole integer number as a regular
    /// floating point value is casted.
    /// @return false if the conversion fails.
    bool toNumber(Int32 &) const;

    /// Casts to the whole integer number as a regular
    /// floating point value is casted.
    /// @return false if the conversion fails.
    bool toNumber(UInt32 &) const;

    /// Casts to the whole integer number as a regular
    /// floating point value is casted.
    /// @return false if the conversion fails.
    bool toNumber(Int64 &) const;

    /// Casts to the whole integer number as a regular
    /// floating point value is casted.
    /// @return false if the conversion fails.
    bool toNumber(UInt64 &) const;

    /// Casts to the floating point number.
    /// @return false if the conversion fails.
    bool toNumber(Double &) const;

    /// Appends the text presentation to the given string.
    void toString(std::string &) const;

    /// Returns the text presentation of the decimal.
    std::string toString() const;

    /// Attempts to parse the decimal value
    /// from its string/text presentation.
    /// @return false on the parsing failure.
    static
    bool
    tryParse(
        const char * buffer,
        size_t bufferSize,
        Decimal &);

    /// Parses the decimal from the string presentation.
    /// @throw The std::exception on a failure.
    static
    Decimal
    parse(
        const char * buffer,
        size_t bufferSize);

private:
    /// The mantissa.
    DecimalMantissa mantissa_;

    /// The exponent.
    DecimalExponent exponent_;
};

ONIXS_FIXENGINE_API std::ostream & operator<<(std::ostream &, Decimal const &);

inline
Decimal::Decimal(
    DecimalMantissa mantissa,
    DecimalExponent exponent)
    : mantissa_(mantissa),
      exponent_(exponent)
{
}

inline
DecimalMantissa
Decimal::mantissa() const
{
    return mantissa_;
}

inline
void
Decimal::mantissa(
    DecimalMantissa value)
{
    mantissa_ = value;
}

inline
DecimalExponent
Decimal::exponent() const
{
    return exponent_;
}

inline
void
Decimal::exponent(
    DecimalExponent value)
{
    exponent_ = value;
}

inline
Decimal::operator Int32() const
{
    Int32 number;

    if(toNumber(number))
        return number;

    throw std::domain_error(
        "Cannot cast value to target type. ");
}

inline
Decimal::operator UInt32() const
{
    UInt32 number;

    if(toNumber(number))
        return number;

    throw std::domain_error(
        "Cannot cast value to target type. ");
}

inline
Decimal::operator Int64() const
{
    Int64 number;

    if(toNumber(number))
        return number;

    throw std::domain_error(
        "Cannot cast value to target type. ");
}

inline
Decimal::operator UInt64() const
{
    UInt64 number;

    if(toNumber(number))
        return number;

    throw std::domain_error(
        "Cannot cast value to target type. ");
}

inline
Decimal::operator Double() const
{
    Double number;

    if(toNumber(number))
        return number;

    throw std::domain_error(
        "Cannot cast value to target type. ");
}

inline
std::string
Decimal::toString() const
{
    std::string presentation;
    toString(presentation);
    return presentation;
}

/// The helper class for the conversion from a string to a number.
struct
    ONIXS_FIXENGINE_API
    Number {
    static
    bool
    tryParse(
        const char * buffer,
        size_t bufferSize,
        Int32 & number);

    static
    bool
    tryParse(
        const char * buffer,
        size_t bufferSize,
        UInt32 & number);

    static
    bool
    tryParse(
        const char * buffer,
        size_t bufferSize,
        Int64 & number);

    static
    bool
    tryParse(
        const char * buffer,
        size_t bufferSize,
        UInt64 & number);

    static
    bool
    tryParse(
        const char * buffer,
        size_t bufferSize,
        Double & number);

    static
    bool
    tryParse(
        const char * buffer,
        size_t bufferSize,
        Decimal & number);
};
}
}