SqMod/shared/Base/Utility.hpp

#ifndef _BASE_UTILITY_HPP_
#define _BASE_UTILITY_HPP_

// ------------------------------------------------------------------------------------------------
#ifdef SQMOD_PLUGIN_API
    #include <ModBase.hpp>
    #include <SqMod.h>
#else
    #include <SqBase.hpp>
    #include <vcmp.h>
#endif // SQMOD_PLUGIN_API

// ------------------------------------------------------------------------------------------------
#include <cmath>
#include <limits>
#include <cassert>

// ------------------------------------------------------------------------------------------------
#include <sqrat.h>

// ------------------------------------------------------------------------------------------------
namespace SqMod {

/* ------------------------------------------------------------------------------------------------
 * Forward declarations.
*/
class Buffer;

/* ------------------------------------------------------------------------------------------------
 * Proxies to communicate with the server.
*/
extern PluginFuncs*         _Func;
extern PluginCallbacks*     _Clbk;
extern PluginInfo*          _Info;

// ------------------------------------------------------------------------------------------------
#ifdef SQMOD_PLUGIN_API

    /* --------------------------------------------------------------------------------------------
     * Proxies to comunicate with the Squirrel plug-in.
    */
    extern HSQAPI           _SqAPI;
    extern HSQEXPORTS       _SqMod;
    extern HSQUIRRELVM      _SqVM;

#endif // SQMOD_PLUGIN_API

/* ------------------------------------------------------------------------------------------------
 * Retrieve the temporary buffer.
*/
SStr GetTempBuff();

/* ------------------------------------------------------------------------------------------------
 * Retrieve the size of the temporary buffer.
*/
Uint32 GetTempBuffSize();

/* ------------------------------------------------------------------------------------------------
 * Output a message only if the _DEBUG was defined.
*/
void OutputDebug(const char * msg, ...);

/* ------------------------------------------------------------------------------------------------
 * Output a formatted user message to the console.
*/
void OutputMessage(const char * msg, ...);

/* ------------------------------------------------------------------------------------------------
 * Output a formatted error message to the console.
*/
void OutputError(const char * msg, ...);

/* ------------------------------------------------------------------------------------------------
 * Generate a formatted string and throw it as a sqrat exception.
*/
void SqThrowF(CCStr str, ...);

/* ------------------------------------------------------------------------------------------------
 * Quickly generate a formatted string on a small static buffer without any memory allocations.
 * NOTE: This does throw an exception in case of failure.
*/
CSStr FmtStr(CSStr str, ...);

/* ------------------------------------------------------------------------------------------------
 * Quickly generate a formatted string on a small static buffer without any memory allocations.
 * NOTE: This does not throw an exception in case of failure.
*/
CSStr ToStrF(CCStr str, ...);

/* ------------------------------------------------------------------------------------------------
 * Generate a formatted string on a temporary buffer and return the string but not the buffer.
 * NOTE: This does not throw an exception in case of failure.
*/
CSStr ToStringF(CCStr str, ...);

/* ------------------------------------------------------------------------------------------------
 * Simple function to check whether the specified string can be considered as a boolean value
*/
bool SToB(CSStr str);

/* ------------------------------------------------------------------------------------------------
 * Retrieve a reference to a null script object.
*/
Object & NullObject();

/* ------------------------------------------------------------------------------------------------
 * Retrieve a reference to a null/empty script table.
*/
Table & NullTable();

/* ------------------------------------------------------------------------------------------------
 * Retrieve a reference to a null/empty script array.
*/
Array & NullArray();

/* ------------------------------------------------------------------------------------------------
 * Retrieve a reference to a null script function.
*/
Function & NullFunction();

/* ------------------------------------------------------------------------------------------------
 * Retrieve a reference to a null string.
*/
String & NullString();

/* ------------------------------------------------------------------------------------------------
 * Compute the next power of two for the specified number.
*/
inline Uint32 NextPow2(Uint32 num)
{
    --num;
    num |= num >> 1;
    num |= num >> 2;
    num |= num >> 4;
    num |= num >> 8;
    num |= num >> 16;
    return ++num;
}

/* ------------------------------------------------------------------------------------------------
 * Retrieve the maximum value of a fundamental type.
*/
template < typename T > constexpr T MaxOf() noexcept
{
    return std::numeric_limits< T >::max();
}

/* ------------------------------------------------------------------------------------------------
 * Retrieve the minimum value of a fundamental type.
*/
template < typename T > constexpr T MinOf() noexcept
{
    return std::numeric_limits< T >::min();
}

/* ------------------------------------------------------------------------------------------------
 * Perform an equality comparison between two values taking into account floating point issues.
*/
template< typename T > inline bool EpsEq(const T a, const T b)
{
    return abs(a - b) <= 0;
}

template <> inline bool EpsEq(const Float32 a, const Float32 b)
{
    return fabs(a - b) <= 0.000001f;
}

template <> inline bool EpsEq(const Float64 a, const Float64 b)
{
    return fabs(a - b) <= 0.000000001d;
}

/* ------------------------------------------------------------------------------------------------
 * Perform a less than comparison between two values taking into account floating point issues.
*/
template< typename T > inline bool EpsLt(const T a, const T b)
{
    return !EpsEq(a, b) && (a < b);
}

template <> inline bool EpsLt(const Float32 a, const Float32 b)
{
    return !EpsEq(a, b) && (a - b) < 0.000001f;
}

template <> inline bool EpsLt(const Float64 a, const Float64 b)
{
    return !EpsEq(a, b) && (a - b) < 0.000000001d;
}

/* ------------------------------------------------------------------------------------------------
 * Perform a greater than comparison between two values taking into account floating point issues.
*/
template< typename T > inline bool EpsGt(const T a, const T b)
{
    return !EpsEq(a, b) && (a > b);
}

template <> inline bool EpsGt(const Float32 a, const Float32 b)
{
    return !EpsEq(a, b) && (a - b) > 0.000001f;
}

template <> inline bool EpsGt(const Float64 a, const Float64 b)
{
    return !EpsEq(a, b) && (a - b) > 0.000000001d;
}

/* ------------------------------------------------------------------------------------------------
 * Perform a less than or equal comparison between two values taking into account
 * floating point issues.
*/
template< typename T > inline bool EpsLtEq(const T a, const T b)
{
    return !EpsEq(a, b) || (a < b);
}

template <> inline bool EpsLtEq(const Float32 a, const Float32 b)
{
    return !EpsEq(a, b) || (a - b) < 0.000001f;
}

template <> inline bool EpsLtEq(const Float64 a, const Float64 b)
{
    return !EpsEq(a, b) || (a - b) < 0.000000001d;
}

/* ------------------------------------------------------------------------------------------------
 * Perform a greater than or equal comparison between two values taking into account
 * floating point issues.
*/
template< typename T > inline bool EpsGtEq(const T a, const T b)
{
    return !EpsEq(a, b) || (a > b);
}

template <> inline bool EpsGtEq(const Float32 a, const Float32 b)
{
    return !EpsEq(a, b) || (a - b) > 0.000001f;
}

template <> inline bool EpsGtEq(const Float64 a, const Float64 b)
{
    return !EpsEq(a, b) || (a - b) > 0.000000001d;
}

/* ------------------------------------------------------------------------------------------------
 * Utility used to convert strings to numeric values and/or backwards.
*/
template < typename T > struct ConvNum;

/* ------------------------------------------------------------------------------------------------
 * Specializations for each numeric type conversion to string and/or backwards.
*/

template <> struct ConvNum< Int8 >
{
    static CCStr ToStr(Int8 v);
    static Int8 FromStr(CCStr s);
    static Int8 FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< Uint8 >
{
    static CCStr ToStr(Uint8 v);
    static Uint8 FromStr(CCStr s);
    static Uint8 FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< Int16 >
{
    static CCStr ToStr(Int16 v);
    static Int16 FromStr(CCStr s);
    static Int16 FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< Uint16 >
{
    static CCStr ToStr(Uint16 v);
    static Uint16 FromStr(CCStr s);
    static Uint16 FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< Int32 >
{
    static CCStr ToStr(Int32 v);
    static Int32 FromStr(CCStr s);
    static Int32 FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< Uint32 >
{
    static CCStr ToStr(Uint32 v);
    static Uint32 FromStr(CCStr s);
    static Uint32 FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< Int64 >
{
    static CCStr ToStr(Int64 v);
    static Int64 FromStr(CCStr s);
    static Int64 FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< Uint64 >
{
    static CCStr ToStr(Uint64 v);
    static Uint64 FromStr(CCStr s);
    static Uint64 FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< LongI >
{
    static CCStr ToStr(LongI v);
    static LongI FromStr(CCStr s);
    static LongI FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< Ulong >
{
    static CCStr ToStr(Ulong v);
    static Ulong FromStr(CCStr s);
    static Ulong FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< Float32 >
{
    static CCStr ToStr(Float32 v);
    static Float32 FromStr(CCStr s);
    static Float32 FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< Float64 >
{
    static CCStr ToStr(Float64 v);
    static Float64 FromStr(CCStr s);
    static Float64 FromStr(CCStr s, Int32 base);
};

template <> struct ConvNum< bool >
{
    static CCStr ToStr(bool v);
    static bool FromStr(CCStr s);
    static bool FromStr(CCStr s, Int32 base);
};

/* ------------------------------------------------------------------------------------------------
 * Utility used to cast between specialized types and perform proper conversion.
*/
template < typename T > struct ConvTo
{
    // --------------------------------------------------------------------------------------------
    static constexpr T Min = std::numeric_limits< T >::min();
    static constexpr T Max = std::numeric_limits< T >::max();

    // --------------------------------------------------------------------------------------------
    template < typename U > static inline T From(U v)
    {
        if (v > Max)
        {
            return Max;
        }
        else if (v < Min)
        {
            return Min;
        }
        return static_cast< T >(v);
    }
};

/* ------------------------------------------------------------------------------------------------
 * Convert a string to 8/16/32 bit signed integers.
*/
template <> template <> inline Int8 ConvTo< Int8 >::From< CCStr >(CCStr v)
{
    return ConvNum< Int8 >::FromStr(v);
}

template <> template <> inline Int16 ConvTo< Int16 >::From< CCStr >(CCStr v)
{
    return ConvNum< Int16 >::FromStr(v);
}

template <> template <> inline Int32 ConvTo< Int32 >::From< CCStr >(CCStr v)
{
    return ConvNum< Int32 >::FromStr(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert a string to 8/16/32 bit unsigned integers.
*/
template <> template <> inline Uint8 ConvTo< Uint8 >::From< CCStr >(CCStr v)
{
    return ConvNum< Uint8 >::FromStr(v);
}

template <> template <> inline Uint16 ConvTo< Uint16 >::From< CCStr >(CCStr v)
{
    return ConvNum< Uint16 >::FromStr(v);
}

template <> template <> inline Uint32 ConvTo< Uint32 >::From< CCStr >(CCStr v)
{
    return ConvNum< Uint32 >::FromStr(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert to 8 bit signed integer from any unsigned integer.
*/
template <> template <> inline Int8 ConvTo< Int8 >::From< Uint8 >(Uint8 v)
{
    return (v >= static_cast< Uint8 >(Max)) ? Max : static_cast< Int8 >(v);
}

template <> template <> inline Int8 ConvTo< Int8 >::From< Uint16 >(Uint16 v)
{
    return (v >= static_cast< Uint8 >(Max)) ? Max : static_cast< Int8 >(v);
}

template <> template <> inline Int8 ConvTo< Int8 >::From< Uint32 >(Uint32 v)
{
    return (v >= static_cast< Uint8 >(Max)) ? Max : static_cast< Int8 >(v);
}

template <> template <> inline Int8 ConvTo< Int8 >::From< Uint64 >(Uint64 v)
{
    return (v >= static_cast< Uint8 >(Max)) ? Max : static_cast< Int8 >(v);
}

template <> template <> inline Int8 ConvTo< Int8 >::From< Ulong >(Ulong v)
{
    return (v >= static_cast< Uint8 >(Max)) ? Max : static_cast< Int8 >(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert to 16 bit signed integer from any unsigned integer.
*/
template <> template <> inline Int16 ConvTo< Int16 >::From< Uint8 >(Uint8 v)
{
    return static_cast< Int16 >(v);
}

template <> template <> inline Int16 ConvTo< Int16 >::From< Uint16 >(Uint16 v)
{
    return (v >= static_cast< Uint16 >(Max)) ? Max : static_cast< Int16 >(v);
}

template <> template <> inline Int16 ConvTo< Int16 >::From< Uint32 >(Uint32 v)
{
    return (v >= static_cast< Uint16 >(Max)) ? Max : static_cast< Int16 >(v);
}

template <> template <> inline Int16 ConvTo< Int16 >::From< Uint64 >(Uint64 v)
{
    return (v >= static_cast< Uint16 >(Max)) ? Max : static_cast< Int16 >(v);
}

template <> template <> inline Int16 ConvTo< Int16 >::From< Ulong >(Ulong v)
{
    return (v >= static_cast< Uint16 >(Max)) ? Max : static_cast< Int16 >(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert to 32 bit signed integer from any unsigned integer.
*/
template <> template <> inline Int32 ConvTo< Int32 >::From< Uint8 >(Uint8 v)
{
    return static_cast< Int32 >(v);
}

template <> template <> inline Int32 ConvTo< Int32 >::From< Uint16 >(Uint16 v)
{
    return static_cast< Int32 >(v);
}

template <> template <> inline Int32 ConvTo< Int32 >::From< Uint32 >(Uint32 v)
{
    return (v >= static_cast< Uint32 >(Max)) ? Max : static_cast< Int32 >(v);
}

template <> template <> inline Int32 ConvTo< Int32 >::From< Uint64 >(Uint64 v)
{
    return (v >= static_cast< Uint32 >(Max)) ? Max : static_cast< Int32 >(v);
}

template <> template <> inline Int32 ConvTo< Int32 >::From< Ulong >(Ulong v)
{
    return (v >= static_cast< Uint32 >(Max)) ? Max : static_cast< Int32 >(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert to 8 bit unsigned integer from any signed integer.
*/
template <> template <> inline Uint8 ConvTo< Uint8 >::From< Int8 >(Int8 v)
{
    return (v <= 0) ? 0 : static_cast< Uint8 >(v);
}

template <> template <> inline Uint8 ConvTo< Uint8 >::From< Int16 >(Int16 v)
{
    if (v <= 0)
    {
        return 0;
    }
    else if (v >= static_cast< Int16 >(Max))
    {
        return Max;
    }
    return static_cast< Uint8 >(v);
}

template <> template <> inline Uint8 ConvTo< Uint8 >::From< Int32 >(Int32 v)
{
    if (v <= 0)
    {
        return 0;
    }
    else if (v >= static_cast< Int16 >(Max))
    {
        return Max;
    }
    return static_cast< Uint8 >(v);
}

template <> template <> inline Uint8 ConvTo< Uint8 >::From< Int64 >(Int64 v)
{
    if (v <= 0)
    {
        return 0;
    }
    else if (v >= static_cast< Int16 >(Max))
    {
        return Max;
    }
    return static_cast< Uint8 >(v);
}

template <> template <> inline Uint8 ConvTo< Uint8 >::From< LongI >(LongI v)
{
    if (v <= 0)
    {
        return 0;
    }
    else if (v >= static_cast< Int16 >(Max))
    {
        return Max;
    }
    return static_cast< Uint8 >(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert to 16 bit unsigned integer from any signed integer.
*/
template <> template <> inline Uint16 ConvTo< Uint16 >::From< Int8 >(Int8 v)
{
    return (v <= 0) ? 0 : static_cast< Uint16 >(v);
}

template <> template <> inline Uint16 ConvTo< Uint16 >::From< Int16 >(Int16 v)
{
    return (v <= 0) ? 0 : static_cast< Uint16 >(v);
}

template <> template <> inline Uint16 ConvTo< Uint16 >::From< Int32 >(Int32 v)
{
    if (v <= 0)
    {
        return 0;
    }
    else if (v >= static_cast< Int32 >(Max))
    {
        return Max;
    }
    return static_cast< Uint16 >(v);
}

template <> template <> inline Uint16 ConvTo< Uint16 >::From< Int64 >(Int64 v)
{
    if (v <= 0)
    {
        return 0;
    }
    else if (v >= static_cast< Int32 >(Max))
    {
        return Max;
    }
    return static_cast< Uint16 >(v);
}

template <> template <> inline Uint16 ConvTo< Uint16 >::From< LongI >(LongI v)
{
    if (v <= 0)
    {
        return 0;
    }
    else if (v >= static_cast< Int32 >(Max))
    {
        return Max;
    }
    return static_cast< Uint16 >(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert to 32 bit unsigned integer from any signed integer.
*/
template <> template <> inline Uint32 ConvTo< Uint32 >::From< Int8 >(Int8 v)
{
    return (v <= 0) ? 0 : static_cast< Uint32 >(v);
}

template <> template <> inline Uint32 ConvTo< Uint32 >::From< Int16 >(Int16 v)
{
    return (v <= 0) ? 0 : static_cast< Uint32 >(v);
}

template <> template <> inline Uint32 ConvTo< Uint32 >::From< Int32 >(Int32 v)
{
    return (v <= 0) ? 0 : static_cast< Uint32 >(v);
}

template <> template <> inline Uint32 ConvTo< Uint32 >::From< Int64 >(Int64 v)
{
    if (v <= 0)
    {
        return 0;
    }
    else if (v >= static_cast< Int64 >(Max))
    {
        return Max;
    }
    return static_cast< Uint32 >(v);
}

template <> template <> inline Uint32 ConvTo< Uint32 >::From< LongI >(LongI v)
{
#if (ULONG_MAX > UINT_MAX)

    if (v <= 0)
    {
        return 0;
    }
    else if (v >= static_cast< Int64 >(Max))
    {
        return Max;
    }
    return static_cast< Uint32 >(v);

#else
    return (v <= 0) ? 0 : static_cast< Uint32 >(v);
#endif
}


/* ------------------------------------------------------------------------------------------------
 * Convert to signed integer from 32 bit floating point number.
*/
template <> template <> inline Int8 ConvTo< Int8 >::From< Float32 >(Float32 v)
{
    if (EpsLt(v, static_cast< Float32 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float32 >(Max)))
    {
        return Max;
    }
    return static_cast< Int8 >(v);
}

template <> template <> inline Int16 ConvTo< Int16 >::From< Float32 >(Float32 v)
{
    if (EpsLt(v, static_cast< Float32 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float32 >(Max)))
    {
        return Max;
    }
    return static_cast< Int16 >(v);
}

template <> template <> inline Int32 ConvTo< Int32 >::From< Float32 >(Float32 v)
{
    if (EpsLt(v, static_cast< Float32 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float32 >(Max)))
    {
        return Max;
    }
    return static_cast< Int32 >(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert to signed integer from 64 bit floating point number.
*/
template <> template <> inline Int8 ConvTo< Int8 >::From< Float64 >(Float64 v)
{
    if (EpsLt(v, static_cast< Float64 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float64 >(Max)))
    {
        return Max;
    }
    return static_cast< Int8 >(v);
}

template <> template <> inline Int16 ConvTo< Int16 >::From< Float64 >(Float64 v)
{
    if (EpsLt(v, static_cast< Float64 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float64 >(Max)))
    {
        return Max;
    }
    return static_cast< Int16 >(v);
}

template <> template <> inline Int32 ConvTo< Int32 >::From< Float64 >(Float64 v)
{
    if (EpsLt(v, static_cast< Float64 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float64 >(Max)))
    {
        return Max;
    }
    return static_cast< Int32 >(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert to unsigned integer from 32 bit floating point number.
*/
template <> template <> inline Uint8 ConvTo< Uint8 >::From< Float32 >(Float32 v)
{
    if (EpsLt(v, static_cast< Float32 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float32 >(Max)))
    {
        return Max;
    }
    return static_cast< Uint8 >(v);
}

template <> template <> inline Uint16 ConvTo< Uint16 >::From< Float32 >(Float32 v)
{
    if (EpsLt(v, static_cast< Float32 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float32 >(Max)))
    {
        return Max;
    }
    return static_cast< Uint16 >(v);
}

template <> template <> inline Uint32 ConvTo< Uint32 >::From< Float32 >(Float32 v)
{
    if (EpsLt(v, static_cast< Float32 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float32 >(Max)))
    {
        return Max;
    }
    return static_cast< Uint32 >(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert to unsigned integer from 64 bit floating point number.
*/
template <> template <> inline Uint8 ConvTo< Uint8 >::From< Float64 >(Float64 v)
{
    if (EpsLt(v, static_cast< Float64 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float64 >(Max)))
    {
        return Max;
    }
    return static_cast< Uint8 >(v);
}

template <> template <> inline Uint16 ConvTo< Uint16 >::From< Float64 >(Float64 v)
{
    if (EpsLt(v, static_cast< Float64 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float64 >(Max)))
    {
        return Max;
    }
    return static_cast< Uint16 >(v);
}

template <> template <> inline Uint32 ConvTo< Uint32 >::From< Float64 >(Float64 v)
{
    if (EpsLt(v, static_cast< Float64 >(Min)))
    {
        return Min;
    }
    else if (EpsGt(v, static_cast< Float64 >(Max)))
    {
        return Max;
    }
    return static_cast< Uint32 >(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert other numeric values to 64 bit signed integer.
*/
template <> struct ConvTo< Int64 >
{
    // --------------------------------------------------------------------------------------------
    static constexpr Int64 Min = std::numeric_limits< Int64 >::min();
    static constexpr Int64 Max = std::numeric_limits< Int64 >::max();

    // --------------------------------------------------------------------------------------------
    template < typename T > static inline Int64 From(T v)
    {
        return static_cast< Int64 >(v);
    }
};

// ------------------------------------------------------------------------------------------------
template <> inline Int64 ConvTo< Int64 >::From< CCStr >(CCStr v)
{
    return ConvNum< Int64 >::FromStr(v);
}

// ------------------------------------------------------------------------------------------------
template <> inline Int64 ConvTo< Int64 >::From< Uint64 >(Uint64 v)
{
    return (v >= static_cast< Uint64 >(Max)) ? Max : static_cast< Int64 >(v);
}

#if (ULONG_MAX > UINT_MAX)

// ------------------------------------------------------------------------------------------------
template <> inline Int64 ConvTo< Int64 >::From< Ulong >(Ulong v)
{
    return (v >= static_cast< Ulong >(Max)) ? Max : static_cast< Int64 >(v);
}

#endif

/* ------------------------------------------------------------------------------------------------
 * Convert other numeric values to 64 bit unsigned integer.
*/
template <> struct ConvTo< Uint64 >
{
    // --------------------------------------------------------------------------------------------
    static constexpr Uint64 Min = std::numeric_limits< Uint64 >::min();
    static constexpr Uint64 Max = std::numeric_limits< Uint64 >::max();

    // --------------------------------------------------------------------------------------------
    template < typename T > static inline Uint64 From(T v)
    {
        return (v <= static_cast< T >(0)) ? 0 : static_cast< Uint64 >(v);
    }
};

// ------------------------------------------------------------------------------------------------
template <> inline Uint64 ConvTo< Uint64 >::From< CCStr >(CCStr v)
{
    return ConvNum< Uint64 >::FromStr(v);
}

// ------------------------------------------------------------------------------------------------
template <> inline Uint64 ConvTo< Uint64 >::From< Float32 >(Float32 v)
{
    return From(ConvTo< Int64 >::From(v));
}

// ------------------------------------------------------------------------------------------------
template <> inline Uint64 ConvTo< Uint64 >::From< Float64 >(Float64 v)
{
    return From(ConvTo< Int64 >::From(v));
}

/* ------------------------------------------------------------------------------------------------
 * Convert other numeric values to signed long integer.
*/
template <> struct ConvTo< LongI >
{
    // --------------------------------------------------------------------------------------------
    static constexpr LongI Min = std::numeric_limits< LongI >::min();
    static constexpr LongI Max = std::numeric_limits< LongI >::max();

    // --------------------------------------------------------------------------------------------
    template < typename T > static inline LongI From(T v)
    {
        return static_cast< LongI >(v);
    }
};

// ------------------------------------------------------------------------------------------------
template <> inline LongI ConvTo< LongI >::From< CCStr >(CCStr v)
{
    return ConvNum< LongI >::FromStr(v);
}

// ------------------------------------------------------------------------------------------------
#if (ULONG_MAX <= UINT_MAX)

template <> inline LongI ConvTo< LongI >::From< Uint32 >(Uint32 v)
{
    return (v >= static_cast< Uint32 >(Max)) ? Max : static_cast< LongI >(v);
}

#endif

// ------------------------------------------------------------------------------------------------
template <> inline LongI ConvTo< LongI >::From< Uint64 >(Uint64 v)
{
    return (v >= static_cast< Uint64 >(Max)) ? Max : static_cast< LongI >(v);
}

// ------------------------------------------------------------------------------------------------
template <> inline LongI ConvTo< LongI >::From< Ulong >(Ulong v)
{
    return (v >= static_cast< Ulong >(Max)) ? Max : static_cast< LongI >(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert other numeric values to unsigned long integer.
*/
template <> struct ConvTo< Ulong >
{
    // --------------------------------------------------------------------------------------------
    static constexpr Ulong Min = std::numeric_limits< Ulong >::min();
    static constexpr Ulong Max = std::numeric_limits< Ulong >::max();

    // --------------------------------------------------------------------------------------------
    template < typename T > static inline Ulong From(T v)
    {
        return (v <= static_cast< T >(0)) ? 0 : static_cast< Ulong >(v);
    }
};

// ------------------------------------------------------------------------------------------------
template <> inline Ulong ConvTo< Ulong >::From< CCStr >(CCStr v)
{
    return ConvNum< Ulong >::FromStr(v);
}

// ------------------------------------------------------------------------------------------------
#if (ULONG_MAX <= UINT_MAX)

template <> inline Ulong ConvTo< Ulong >::From< Int64 >(Int64 v)
{
    if (v <= 0)
    {
        return Min;
    }
    else if (v >= static_cast< Int64 >(Max))
    {
        return Max;
    }
    return static_cast< Ulong >(v);
}

template <> inline Ulong ConvTo< Ulong >::From< Uint64 >(Uint64 v)
{
    return (v >= Max) ? Max : static_cast< Ulong >(v);
}

#endif

// ------------------------------------------------------------------------------------------------
template <> inline Ulong ConvTo< Ulong >::From< Float32 >(Float32 v)
{
    return From(ConvTo< LongI >::From(v));
}

// ------------------------------------------------------------------------------------------------
template <> inline Ulong ConvTo< Ulong >::From< Float64 >(Float64 v)
{
    return From(ConvTo< LongI >::From(v));
}

/* ------------------------------------------------------------------------------------------------
 * Convert other numeric values to 32 bit floating point value.
*/
template <> struct ConvTo< Float32 >
{
    // --------------------------------------------------------------------------------------------
    static constexpr Float32 Min = std::numeric_limits< Float32 >::min();
    static constexpr Float32 Max = std::numeric_limits< Float32 >::max();

    // --------------------------------------------------------------------------------------------
    template < typename T > static inline Float32 From(T v)
    {
        return static_cast< Float32 >(v);
    }
};

// ------------------------------------------------------------------------------------------------
template <> inline Float32 ConvTo< Float32 >::From< CCStr >(CCStr v)
{
    return ConvNum< Float32 >::FromStr(v);
}

// ------------------------------------------------------------------------------------------------
template <> inline Float32 ConvTo< Float32 >::From< Float64 >(Float64 v)
{
    if (EpsGt(v, static_cast< Float64 >(Max)))
    {
        return Max;
    }
    else if (EpsLt(v, static_cast< Float64 >(Min)))
    {
        return Min;
    }
    return static_cast< Float32 >(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert other numeric values to 64 bit floating point value.
*/
template <> struct ConvTo< Float64 >
{
    // --------------------------------------------------------------------------------------------
    static constexpr Float64 Min = std::numeric_limits< Float64 >::min();
    static constexpr Float64 Max = std::numeric_limits< Float64 >::max();

    // --------------------------------------------------------------------------------------------
    template < typename T > static inline Float64 From(T v)
    {
        return static_cast< Float64 >(v);
    }
};

// ------------------------------------------------------------------------------------------------
template <> inline Float64 ConvTo< Float64 >::From< CCStr >(CCStr v)
{
    return ConvNum< Float64 >::FromStr(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert other numeric values to boolean value.
*/
template <> struct ConvTo< bool >
{
    // --------------------------------------------------------------------------------------------
    template < typename T > static inline bool From(T v)
    {
        return static_cast< bool >(v);
    }
};

// ------------------------------------------------------------------------------------------------
template <> inline bool ConvTo< bool >::From< CCStr >(CCStr v)
{
    return ConvNum< bool >::FromStr(v);
}

/* ------------------------------------------------------------------------------------------------
 * Convert other numeric values to string value.
*/
template <> struct ConvTo< CStr >
{
    // --------------------------------------------------------------------------------------------
    template < typename T > static inline CStr From(T v)
    {
        return const_cast< CStr >(ConvNum< T >::ToStr(v));
    }
};

/* ------------------------------------------------------------------------------------------------
 * Convert other numeric values to string value.
*/
template <> struct ConvTo< CCStr >
{
    // --------------------------------------------------------------------------------------------
    template < typename T > static inline CCStr From(T v)
    {
        return ConvNum< T >::ToStr(v);
    }
};

/* ------------------------------------------------------------------------------------------------
 * Force a value to be within a certain range.
*/
template< typename T, typename U, typename V > inline T Clamp(T val, U min, V max)
{
    // Is the specified value bellow the minimum?
    if (val < min)
    {
        return min;
    }
    // Is the specified value above the maximum?
    else if (val > max)
    {
        return max;
    }
    // Return the value as is
    return val;
}

/* ------------------------------------------------------------------------------------------------
 * Force a value to be higher then than the imposed limit.
*/
template< typename T, typename U > inline T ClampMin(T val, U min)
{
    // Is the specified value bellow the minimum?
    if (val < min)
    {
        return min;
    }
    // Return the value as is
    return val;
}

/* ------------------------------------------------------------------------------------------------
 * Force a value to be smaller then than the imposed limit.
*/
template< typename T, typename U > inline T ClampMax(T val, U max)
{
    // Is the specified value above the maximum?
    if (val > max)
    {
        return max;
    }
    // Return the value as is
    return val;
}

/* ------------------------------------------------------------------------------------------------
 * Force a value to be within a certain range.
*/
template<> inline Float32 Clamp(Float32 val, Float32 min, Float32 max)
{
    // Is the specified value bellow the minimum?
    if (EpsLt(val, min))
    {
        return min;
    }
    // Is the specified value above the maximum?
    else if (EpsGt(val, max))
    {
        return max;
    }
    // Return the value as is
    return val;
}

/* ------------------------------------------------------------------------------------------------
 * Force a value to be within a certain range.
*/
template<> inline Float64 Clamp(Float64 val, Float64 min, Float64 max)
{
    // Is the specified value bellow the minimum?
    if (EpsLt(val, min))
    {
        return min;
    }
    // Is the specified value above the maximum?
    else if (EpsGt(val, max))
    {
        return max;
    }
    // Return the value as is
    return val;
}

/* ------------------------------------------------------------------------------------------------
 * Force a value to be the boundaries of the specified type.
*/
template < typename T, typename U > inline U ClampL(T v)
{
    return ConvTo< U >::From(v);
}

/* ------------------------------------------------------------------------------------------------
 * Helper class allows the use of functions with ctype style as predicate for algorithms.
*/
struct IsCType
{
    // ------------------------------------------------------------------------------------------------
    typedef int (*CTypeFn)(int); // The signature of a ctype function.

private:

    // ------------------------------------------------------------------------------------------------
    CTypeFn m_Fn; // Pointer to the actual function that does the comparison.

public:

    /* ------------------------------------------------------------------------------------------------
     * Base constructor.
    */
    IsCType(CTypeFn fn)
        : m_Fn(fn)
    {
        /* ... */
    }

    /* ------------------------------------------------------------------------------------------------
     * Function call operator.
    */
    template < typename T > bool operator () (T c)
    {
        return (m_Fn(static_cast< int >(c)) != 0);
    }
};

/* ------------------------------------------------------------------------------------------------
 * Helper class allows the use of functions with ctype style as predicate for algorithms.
*/
struct IsNotCType
{
    // ------------------------------------------------------------------------------------------------
    typedef int (*CTypeFn)(int); // The signature of a ctype function.

private:

    // ------------------------------------------------------------------------------------------------
    CTypeFn m_Fn; // Pointer to the actual function that does the comparison.

public:

    /* ------------------------------------------------------------------------------------------------
     * Base constructor.
    */
    IsNotCType(CTypeFn fn)
        : m_Fn(fn)
    {
        /* ... */
    }

    /* ------------------------------------------------------------------------------------------------
     * Function call operator.
    */
    template < typename T > bool operator () (T c)
    {
        return (m_Fn(static_cast< int >(c)) == 0);
    }
};

/* ------------------------------------------------------------------------------------------------
 * Utility implementing RAII to toggle a bit mask on and off at all costs.
*/
template < typename T > struct BitGuard
{
private:

    /* ------------------------------------------------------------------------------------------------
     * The lock to be toggled.
    */
    T & m_Lock;

    /* ------------------------------------------------------------------------------------------------
     * The mask to be applied.
    */
    T   m_Mask;

public:

    /* ------------------------------------------------------------------------------------------------
     * Base constructor.
    */
    BitGuard(T & lock, T mask)
        : m_Lock(lock), m_Mask(mask)
    {
        // Apply the specified mask
        m_Lock |= m_Mask;
    }

    /* ------------------------------------------------------------------------------------------------
     * Destructor.
    */
    ~BitGuard()
    {
        // In case one of the bits was turned off in the meantime
        m_Lock |= m_Mask;
        // Now turn off all the bits in the mask
        m_Lock ^= m_Mask;
    }
};

// ------------------------------------------------------------------------------------------------
typedef BitGuard< Uint8 >    BitGuardU8;
typedef BitGuard< Uint16 >   BitGuardU16;
typedef BitGuard< Uint32 >   BitGuardU32;

/* ------------------------------------------------------------------------------------------------
 * Implements RAII to restore the VM stack to it's initial size on function exit.
*/
struct StackGuard
{
    /* --------------------------------------------------------------------------------------------
     * Default constructor.
    */
    StackGuard()
        : m_VM(DefaultVM::Get()), m_Top(sq_gettop(m_VM))
    {
        /* ... */
    }

    /* --------------------------------------------------------------------------------------------
     * Base constructor.
    */
    StackGuard(HSQUIRRELVM vm)
        : m_VM(vm), m_Top(sq_gettop(vm))
    {
        /* ... */
    }

    /* --------------------------------------------------------------------------------------------
     * Copy constructor. (disabled)
    */
    StackGuard(const StackGuard &) = delete;

    /* --------------------------------------------------------------------------------------------
     * Move constructor. (disabled)
    */
    StackGuard(StackGuard &&) = delete;

    /* --------------------------------------------------------------------------------------------
     * Destructor.
    */
    ~StackGuard()
    {
        sq_pop(m_VM, sq_gettop(m_VM) - m_Top);
    }

    /* --------------------------------------------------------------------------------------------
     * Copy assignment operator. (disabled)
    */
    StackGuard & operator = (const StackGuard &) = delete;

    /* --------------------------------------------------------------------------------------------
     * Move assignment operator. (disabled)
    */
    StackGuard & operator = (StackGuard &&) = delete;

private:

    // --------------------------------------------------------------------------------------------
    HSQUIRRELVM m_VM; // The VM where the stack should be restored.
    Int32       m_Top; // The top of the stack when this instance was created.
};

/* ------------------------------------------------------------------------------------------------
 * Helper structure for retrieving a value from the stack as a string or a formatted string.
*/
struct StackStrF
{
    // --------------------------------------------------------------------------------------------
    CSStr       mPtr; // Pointer to the C string that was retrieved.
    SQInteger   mLen; // The string length if it could be retrieved.
    SQRESULT    mRes; // The result of the retrieval attempts.
    HSQOBJECT   mObj; // Strong reference to the string object.
    HSQUIRRELVM mVM; // The associated virtual machine.

    /* --------------------------------------------------------------------------------------------
     * Base constructor.
    */
    StackStrF(HSQUIRRELVM vm, SQInteger idx, bool fmt = true);

    /* --------------------------------------------------------------------------------------------
     * Copy constructor. (disabled)
    */
    StackStrF(const StackStrF & o) = delete;

    /* --------------------------------------------------------------------------------------------
     * Copy constructor. (disabled)
    */
    StackStrF(StackStrF && o) = delete;

    /* --------------------------------------------------------------------------------------------
     * Destructor.
    */
    ~StackStrF();

    /* --------------------------------------------------------------------------------------------
     * Copy constructor. (disabled)
    */
    StackStrF & operator = (const StackStrF & o) = delete;

    /* --------------------------------------------------------------------------------------------
     * Copy constructor. (disabled)
    */
    StackStrF & operator = (StackStrF && o) = delete;
};

/* ------------------------------------------------------------------------------------------------
 * Retrieve the string representation of a certain type.
*/
CSStr SqTypeName(SQObjectType type);

/* ------------------------------------------------------------------------------------------------
 * Retrieve the string representation of a certain type from a value on the stack.
*/
String SqTypeName(HSQUIRRELVM vm, SQInteger idx);

/* ------------------------------------------------------------------------------------------------
 * Create a script object from the specified value on the default VM.
*/
template < typename T > Object MakeObject(const T & v)
{
    // Remember the current stack size
    const StackGuard sg;
    // Transform the specified value into a script object
    PushVar< T >(DefaultVM::Get(), v);
    // Get the object from the stack and return it
    return Var< Object >(DefaultVM::Get(), -1).value;
}

/* ------------------------------------------------------------------------------------------------
 * Create a script object from the specified value on the specified VM.
*/
template < typename T > Object MakeObject(HSQUIRRELVM vm, const T & v)
{
    // Remember the current stack size
    const StackGuard sg;
    // Transform the specified value into a script object
    PushVar< T >(vm, v);
    // Get the object from the stack and return it
    return Var< Object >(vm, -1).value;
}

/* ------------------------------------------------------------------------------------------------
 * Create a script string instance from a buffer.
*/
Object BufferToStrObj(const Buffer & b);

/* ------------------------------------------------------------------------------------------------
 * Create a script string instance from a portion of a buffer.
*/
Object BufferToStrObj(const Buffer & b, Uint32 size);

/* ------------------------------------------------------------------------------------------------
 * Create a signed long integer instance from an integer.
*/
Object MakeSLongObj(Int64 value);

/* ------------------------------------------------------------------------------------------------
 * Create a unsigned long integer instance from an integer.
*/
Object MakeULongObj(Uint64 value);

/* ------------------------------------------------------------------------------------------------
 * Create a signed long integer instance from an integer.
*/
Object MakeSLongObj(HSQUIRRELVM vm, Int64 value);

/* ------------------------------------------------------------------------------------------------
 * Create a unsigned long integer instance from an integer.
*/
Object MakeULongObj(HSQUIRRELVM vm, Uint64 value);

/* ------------------------------------------------------------------------------------------------
 * Retrieve a signed 64 bit integer from an signed long integer instance.
*/
Int64 FetchSLongObjVal(const Object & value);

/* ------------------------------------------------------------------------------------------------
 * Retrieve a unsigned 64 bit integer from an unsigned long integer instance.
*/
Uint64 FetchULongObjVal(const Object & value);

/* ------------------------------------------------------------------------------------------------
 * Retrieve the date components from a date instance.
*/
SQRESULT FetchDateObjVal(const Object & value, Uint16 & year, Uint8 & month, Uint8 & day);

/* ------------------------------------------------------------------------------------------------
 * Retrieve the date components from a date instance as a string.
*/
CSStr FetchDateObjStr(const Object & value);

/* ------------------------------------------------------------------------------------------------
 * Retrieve the time components from a date instance.
*/
SQRESULT FetchTimeObjVal(const Object & value, Uint8 & hour, Uint8 & minute, Uint8 & second);

/* ------------------------------------------------------------------------------------------------
 * Retrieve the time components from a date instance.
*/
SQRESULT FetchTimeObjVal(const Object & value, Uint8 & hour, Uint8 & minute, Uint8 & second, Uint16 & millisecond);

/* ------------------------------------------------------------------------------------------------
 * Retrieve the time components from a date instance as a string.
*/
CSStr FetchTimeObjStr(const Object & value);

/* ------------------------------------------------------------------------------------------------
 * Retrieve the time components from a date instance as the number of seconds.
*/
Int32 FetchTimeObjSeconds(const Object & value);

/* ------------------------------------------------------------------------------------------------
 * Retrieve the date-time components from a date-time instance.
*/
SQRESULT FetchDatetimeObjVal(const Object & value, Uint16 & year, Uint8 & month, Uint8 & day, Uint8 & hour,
                                Uint8 & minute, Uint8 & second);

/* ------------------------------------------------------------------------------------------------
 * Retrieve the date-time components from a date-time instance.
*/
SQRESULT FetchDatetimeObjVal(const Object & value, Uint16 & year, Uint8 & month, Uint8 & day, Uint8 & hour,
                                Uint8 & minute, Uint8 & second, Uint16 & millisecond);

/* ------------------------------------------------------------------------------------------------
 * Retrieve the date-time components from a date-time instance as a string.
*/
CSStr FetchDatetimeObjStr(const Object & value);

/* ------------------------------------------------------------------------------------------------
 * Attempt to pop the value at the specified index on the stack as a native integer.
*/
SQInteger PopStackInteger(HSQUIRRELVM vm, SQInteger idx);

/* ------------------------------------------------------------------------------------------------
 * Attempt to pop the value at the specified index on the stack as a native float.
*/
SQFloat PopStackFloat(HSQUIRRELVM vm, SQInteger idx);

/* ------------------------------------------------------------------------------------------------
 * Attempt to pop the value at the specified index on the stack as a signed long integer.
*/
Int64 PopStackSLong(HSQUIRRELVM vm, SQInteger idx);

/* ------------------------------------------------------------------------------------------------
 * Attempt to pop the value at the specified index on the stack as an unsigned long integer.
*/
Uint64 PopStackULong(HSQUIRRELVM vm, SQInteger idx);

} // Namespace:: SqMod

#endif // _BASE_UTILITY_HPP_