/***
    Copyright (C) 2021 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: IRandomDevice.hpp
    Date: 2021-9-3
    Author: Reece
***/
#pragma once 

namespace Aurora::RNG
{
    static const auto kSizeRNGDevice = 256;

    struct IRandomDevice
    {
        virtual IO::IStreamReader *    ToStreamReader() = 0;
        virtual Memory::MemoryViewRead ToSeed() = 0;

        virtual void                Read(Memory::MemoryViewWrite view) = 0;

        virtual AuString            NextString(AuUInt32 uLength, ERngStringCharacters type = ERngStringCharacters::eAlphaCharacters) = 0;
        virtual void                NextString(char *pString, AuUInt32 uLength, ERngStringCharacters type = ERngStringCharacters::eAlphaCharacters) = 0;

        virtual AuUInt8             NextByte() = 0;
        virtual bool                NextBoolean() = 0;
        virtual AuUInt32            NextU32() = 0;
        virtual AuUInt32            NextU32Range(AuUInt32 uMin, AuUInt32 uMax) = 0;
        virtual AuInt32             NextI32Range(AuInt32 iMin, AuInt32 iMax) = 0;
        virtual AuUInt64            NextU64() = 0;
        virtual AuUInt64            NextU64Range(AuUInt64 uMin, AuUInt64 uMax) = 0;
        virtual AuInt64             NextI64Range(AuInt64 iMin, AuInt64 iMax) = 0;
        virtual AuVec2              NextVec2(AuVec2 boundA, AuVec2 boundB) = 0;
        virtual AuVec2              NextVec2Sorted(AuVec2 min, AuVec2 max) = 0;
        virtual AuVec3              NextVec3(AuVec3 boundA, AuVec3 boundB) = 0;
        virtual AuVec3              NextVec3Sorted(AuVec3 min, AuVec3 max) = 0;
        virtual AuVec4              NextVec4(AuVec4 boundA, AuVec4 boundB) = 0;
        virtual AuVec4              NextVec4Sorted(AuVec4 min, AuVec4 max) = 0;
        virtual AuVecD2             NextVecD2(AuVecD2 boundA, AuVecD2 boundB) = 0;
        virtual AuVecD2             NextVecD2Sorted(AuVecD2 min, AuVecD2 max) = 0;
        virtual AuVecD3             NextVecD3(AuVecD3 boundA, AuVecD3 boundB) = 0;
        virtual AuVecD3             NextVecD3Sorted(AuVecD3 min, AuVecD3 max) = 0;
        virtual AuVecD4             NextVecD4(AuVecD4 boundA, AuVecD4 boundB) = 0;
        virtual AuVecD4             NextVecD4Sorted(AuVecD4 min, AuVecD4 max) = 0;
        virtual double              NextDecimal() = 0;
        virtual double              NextNumber(double dMin, double dMax) = 0;
        virtual AuUInt32            NextIndex(AuUInt32 uCount /* = max + 1*/) = 0;
        virtual uuids::uuid         NextUUID() = 0;

        // Note: Fast arrays are deterministic with little seed entropy (usually 64bits, sometimes 32bits).
        // 
        //       Wont mitigate; use the slower non-fast variants if each numeric value (if not vec) OR 
        //                      a *group* of N-components of each vector (if vec) need to be unique.
        // 
        //       Fast arrays simply rehash the previous bits to get the next component. While hopefully
        //       perfectly uniform (otherwise the hash wouldn't be a good hash), it's entirely possible
        //       to extrapolate the next value in the sequence.
        // 
        //       In addition, this applies to non-fast components of each vector; given an X component,
        //       you can derive the Y and Z, even under non-fast functions. Fast vectors means the next
        //       vector can be extrapolated from the previous group of vector components; nonfast, you
        //       can only solve Y and Z. Fast vector arrays only have 64bits of entropy extrapolated to 
        //       52bits * uCount * N bits of fully deterministic components; nonfast vector arrays have
        //       64bits * uCount bits of entropy, extrapolated to 52bits * uCount * N bits of partially
        //       in-vector extrapolatable bits.
        //  
        //       Also note, it might not even be possible to extrapolate these components in practice.
        //       This is because each component has some bits chucked away when shoving the seed into
        //       the mantissa, and then each component gets manipulated using the same range provided
        //       by the bound[..]s or min/max vecs parameters. Some bruteforce would be required.
        //       

        // Wont add generics: if constexprs are very modern; we have slight differences between types; 
        //                    generics would needs extra tags to handle memory view (near?) alloc-less
        //                    operations! Method<T, bool, bool> is too ambigious compared to simple
        //                    unoverloaded and verbose/self-documenting method names. Also easier to bind
        //                    this way.

        virtual AuList<AuInt32>     NextArrayI32Range(AuUInt32 uCount, AuInt32 iMin, AuInt32 iMax) = 0;
        virtual AuList<AuInt32>     NextArrayI32RangeFast(AuUInt32 uCount, AuInt32 iMin, AuInt32 iMax) = 0;
        virtual AuList<AuUInt32>    NextArrayU32Range(AuUInt32 uCount, AuUInt32 uMin, AuUInt32 uMax) = 0;
        virtual AuList<AuUInt32>    NextArrayU32RangeFast(AuUInt32 uCount, AuUInt32 uMin, AuUInt32 uMax) = 0;
        virtual AuList<AuInt64>     NextArrayI64Range(AuUInt32 uCount, AuInt64 iMin, AuInt64 iMax) = 0;
        virtual AuList<AuInt64>     NextArrayI64RangeFast(AuUInt32 uCount, AuInt64 iMin, AuInt64 iMax) = 0;
        virtual AuList<AuUInt64>    NextArrayU64Range(AuUInt32 uCount, AuUInt64 uMin, AuUInt64 uMax) = 0;
        virtual AuList<AuUInt64>    NextArrayU64RangeFast(AuUInt32 uCount, AuUInt64 uMin, AuUInt64 uMax) = 0;
        virtual AuList<AuUInt32>    NextArrayU32Mask(AuUInt32 uCount, AuUInt32 uMask) = 0;
        virtual AuList<AuUInt64>    NextArrayU64Mask(AuUInt32 uCount, AuUInt64 uMask) = 0;
        virtual AuList<double>      NextArrayDoubleRange(AuUInt32 uCount, double dMin, double dMax) = 0;
        virtual AuList<double>      NextArrayDoubleRangeFast(AuUInt32 uCount, double dMin, double dMax) = 0;
        virtual AuList<AuInt32>     NextArrayI32(AuUInt32 uCount) = 0;
        virtual AuList<AuUInt32>    NextArrayU32(AuUInt32 uCount) = 0;
        virtual AuList<AuInt64>     NextArrayI64(AuUInt32 uCount) = 0;
        virtual AuList<AuUInt64>    NextArrayU64(AuUInt32 uCount) = 0;
        virtual AuList<AuVec2>      NextArrayVec2(AuUInt32 uCount, AuVec2 boundA, AuVec2 boundB) = 0;
        virtual AuList<AuVec2>      NextArrayVec2Fast(AuUInt32 uCount, AuVec2 boundA, AuVec2 boundB) = 0;
        virtual AuList<AuVec2>      NextArrayVec2Sorted(AuUInt32 uCount, AuVec2 min, AuVec2 max) = 0;
        virtual AuList<AuVec2>      NextArrayVec2SortedFast(AuUInt32 uCount, AuVec2 min, AuVec2 max) = 0;
        virtual AuList<AuVec3>      NextArrayVec3(AuUInt32 uCount, AuVec3 boundA, AuVec3 boundB) = 0;
        virtual AuList<AuVec3>      NextArrayVec3Fast(AuUInt32 uCount, AuVec3 boundA, AuVec3 boundB) = 0;
        virtual AuList<AuVec3>      NextArrayVec3Sorted(AuUInt32 uCount, AuVec3 min, AuVec3 max) = 0;
        virtual AuList<AuVec3>      NextArrayVec3SortedFast(AuUInt32 uCount, AuVec3 min, AuVec3 max) = 0;
        virtual AuList<AuVec4>      NextArrayVec4(AuUInt32 uCount, AuVec4 boundA, AuVec4 boundB) = 0;
        virtual AuList<AuVec4>      NextArrayVec4Fast(AuUInt32 uCount, AuVec4 boundA, AuVec4 boundB) = 0;
        virtual AuList<AuVec4>      NextArrayVec4Sorted(AuUInt32 uCount, AuVec4 min, AuVec4 max) = 0;
        virtual AuList<AuVec4>      NextArrayVec4SortedFast(AuUInt32 uCount, AuVec4 min, AuVec4 max) = 0;
        virtual AuList<AuVecD2>     NextArrayVecD2(AuUInt32 uCount, AuVecD2 boundA, AuVecD2 boundB) = 0;
        virtual AuList<AuVecD2>     NextArrayVecD2Fast(AuUInt32 uCount, AuVecD2 boundA, AuVecD2 boundB) = 0;
        virtual AuList<AuVecD2>     NextArrayVecD2Sorted(AuUInt32 uCount, AuVecD2 min, AuVecD2 max) = 0;
        virtual AuList<AuVecD2>     NextArrayVecD2SortedFast(AuUInt32 uCount, AuVecD2 min, AuVecD2 max) = 0;
        virtual AuList<AuVecD3>     NextArrayVecD3(AuUInt32 uCount, AuVecD3 boundA, AuVecD3 boundB) = 0;
        virtual AuList<AuVecD3>     NextArrayVecD3Fast(AuUInt32 uCount, AuVecD3 boundA, AuVecD3 boundB) = 0;
        virtual AuList<AuVecD3>     NextArrayVecD3Sorted(AuUInt32 uCount, AuVecD3 min, AuVecD3 max) = 0;
        virtual AuList<AuVecD3>     NextArrayVecD3SortedFast(AuUInt32 uCount, AuVecD3 min, AuVecD3 max) = 0;
        virtual AuList<AuVecD4>     NextArrayVecD4(AuUInt32 uCount, AuVecD4 boundA, AuVecD4 boundB) = 0;
        virtual AuList<AuVecD4>     NextArrayVecD4Fast(AuUInt32 uCount, AuVecD4 boundA, AuVecD4 boundB) = 0;
        virtual AuList<AuVecD4>     NextArrayVecD4Sorted(AuUInt32 uCount, AuVecD4 min, AuVecD4 max) = 0;
        virtual AuList<AuVecD4>     NextArrayVecD4SortedFast(AuUInt32 uCount, AuVecD4 min, AuVecD4 max) = 0;
        virtual AuList<double>      NextArrayDouble(AuUInt32 uCount) = 0;
        virtual AuList<double>      NextArrayDecimals(AuUInt32 uCount) = 0;
        virtual AuList<double>      NextArrayDecimalsFast(AuUInt32 uCount) = 0;
        virtual AuList<uuids::uuid> NextArrayUUIDs(AuUInt32 uCount) = 0;
        virtual AuUInt              NextArrayI32RangeInView(Memory::MemoryViewWrite write, AuInt32 iMin, AuInt32 iMax) = 0;
        virtual AuUInt              NextArrayI32RangeFastInView(Memory::MemoryViewWrite write, AuInt32 iMin, AuInt32 iMax) = 0;
        virtual AuUInt              NextArrayU32RangeInView(Memory::MemoryViewWrite write, AuUInt32 uMin, AuUInt32 uMax) = 0;
        virtual AuUInt              NextArrayU32RangeFastInView(Memory::MemoryViewWrite write, AuUInt32 uMin, AuUInt32 uMax) = 0;
        virtual AuUInt              NextArrayI64RangeInView(Memory::MemoryViewWrite write, AuInt64 iMin, AuInt64 iMax) = 0;
        virtual AuUInt              NextArrayI64RangeFastInView(Memory::MemoryViewWrite write, AuInt64 iMin, AuInt64 iMax) = 0;
        virtual AuUInt              NextArrayU64RangeInView(Memory::MemoryViewWrite write, AuUInt64 uMin, AuUInt64 uMax) = 0;
        virtual AuUInt              NextArrayU64RangeFastInView(Memory::MemoryViewWrite write, AuUInt64 uMin, AuUInt64 uMax) = 0;
        virtual AuUInt              NextArrayU32MaskInView(Memory::MemoryViewWrite write, AuUInt32 uMask) = 0;
        virtual AuUInt              NextArrayU64MaskInView(Memory::MemoryViewWrite write, AuUInt64 uMask) = 0;
        virtual AuUInt              NextArrayDoubleRangeInView(Memory::MemoryViewWrite write, double dMin, double dMax) = 0;
        virtual AuUInt              NextArrayDoubleRangeFastInView(Memory::MemoryViewWrite write, double dMin, double dMax) = 0;
        virtual AuUInt              NextArrayI32InView(Memory::MemoryViewWrite write) = 0;
        virtual AuUInt              NextArrayU32InView(Memory::MemoryViewWrite write) = 0;
        virtual AuUInt              NextArrayI64InView(Memory::MemoryViewWrite write) = 0;
        virtual AuUInt              NextArrayU64InView(Memory::MemoryViewWrite write) = 0;
        virtual AuUInt              NextArrayVec2InView(Memory::MemoryViewWrite write, AuVec2 boundA, AuVec2 boundB) = 0;
        virtual AuUInt              NextArrayVec2FastInView(Memory::MemoryViewWrite write, AuVec2 boundA, AuVec2 boundB) = 0;
        virtual AuUInt              NextArrayVec2SortedInView(Memory::MemoryViewWrite write, AuVec2 min, AuVec2 max) = 0;
        virtual AuUInt              NextArrayVec2SortedFastInView(Memory::MemoryViewWrite write, AuVec2 min, AuVec2 max) = 0;
        virtual AuUInt              NextArrayVec3InView(Memory::MemoryViewWrite write, AuVec3 boundA, AuVec3 boundB) = 0;
        virtual AuUInt              NextArrayVec3FastInView(Memory::MemoryViewWrite write, AuVec3 boundA, AuVec3 boundB) = 0;
        virtual AuUInt              NextArrayVec3SortedInView(Memory::MemoryViewWrite write, AuVec3 min, AuVec3 max) = 0;
        virtual AuUInt              NextArrayVec3SortedFastInView(Memory::MemoryViewWrite write, AuVec3 min, AuVec3 max) = 0;
        virtual AuUInt              NextArrayVec4InView(Memory::MemoryViewWrite write, AuVec4 boundA, AuVec4 boundB) = 0;
        virtual AuUInt              NextArrayVec4FastInView(Memory::MemoryViewWrite write, AuVec4 boundA, AuVec4 boundB) = 0;
        virtual AuUInt              NextArrayVec4SortedInView(Memory::MemoryViewWrite write, AuVec4 min, AuVec4 max) = 0;
        virtual AuUInt              NextArrayVec4SortedFastInView(Memory::MemoryViewWrite write, AuVec4 min, AuVec4 max) = 0;
        virtual AuUInt              NextArrayVecD2InView(Memory::MemoryViewWrite write, AuVecD2 boundA, AuVecD2 boundB) = 0;
        virtual AuUInt              NextArrayVecD2FastInView(Memory::MemoryViewWrite write, AuVecD2 boundA, AuVecD2 boundB) = 0;
        virtual AuUInt              NextArrayVecD2SortedInView(Memory::MemoryViewWrite write, AuVecD2 min, AuVecD2 max) = 0;
        virtual AuUInt              NextArrayVecD2SortedFastInView(Memory::MemoryViewWrite write, AuVecD2 min, AuVecD2 max) = 0;
        virtual AuUInt              NextArrayVecD3InView(Memory::MemoryViewWrite write, AuVecD3 boundA, AuVecD3 boundB) = 0;
        virtual AuUInt              NextArrayVecD3FastInView(Memory::MemoryViewWrite write, AuVecD3 boundA, AuVecD3 boundB) = 0;
        virtual AuUInt              NextArrayVecD3SortedInView(Memory::MemoryViewWrite write, AuVecD3 min, AuVecD3 max) = 0;
        virtual AuUInt              NextArrayVecD3SortedFastInView(Memory::MemoryViewWrite write, AuVecD3 min, AuVecD3 max) = 0;
        virtual AuUInt              NextArrayVecD4InView(Memory::MemoryViewWrite write, AuVecD4 boundA, AuVecD4 boundB) = 0;
        virtual AuUInt              NextArrayVecD4FastInView(Memory::MemoryViewWrite write, AuVecD4 boundA, AuVecD4 boundB) = 0;
        virtual AuUInt              NextArrayVecD4SortedInView(Memory::MemoryViewWrite write, AuVecD4 min, AuVecD4 max) = 0;
        virtual AuUInt              NextArrayVecD4SortedFastInView(Memory::MemoryViewWrite write, AuVecD4 min, AuVecD4 max) = 0;
        virtual AuUInt              NextArrayDoubleInView(Memory::MemoryViewWrite write) = 0;
        virtual AuUInt              NextArrayDecimalsInView(Memory::MemoryViewWrite write) = 0;
        virtual AuUInt              NextArrayDecimalsFastInView(Memory::MemoryViewWrite write) = 0;
        virtual AuUInt              NextArrayUUIDsInView(Memory::MemoryViewWrite write) = 0;

    
        template<typename T, int N>
        inline void NextFillArray(T(&array)[N])
        {
            Read(Memory::MemoryViewWrite(array));
        }

        template<typename T>
        inline void NextFillArray(T *pArray, AuUInt32 uCount)
        {
            Read(Memory::MemoryViewWrite(pArray, uCount * sizeof(T)));
        }

        template<typename T>
        void NextFillRange(T &container)
        {
            NextFillArray(container.begin(), container.end() - container.begin());
        }

        inline void NextFillBuffer(Memory::ByteBuffer &buffer)
        {
            auto view = buffer.GetNextLinearWrite();
            NextFillRange(view);
            buffer.writePtr += view.length;
        }

        /**
         * @brief
         * @deprecated
        */
        inline void NextFillRange(Memory::ByteBuffer &buffer)
        {
            NextFillBuffer(buffer);
        }
    
        template<typename T>
        inline T NextFillTmpl()
        {
            T ret {};
            Read(Memory::MemoryViewWrite(&ret, sizeof(T)));
            return ret;
        }

        template<typename T>
        inline T NextIterator(T begin, T end)
        {
            auto nextItr = begin;
            auto uCount = std::distance(begin, end);
            std::advance(nextItr, NextIndex(uCount));
            return nextItr;
        }

        template<typename T>
        inline T &NextArray(T *pItems, AuUInt32 uCount)
        {
            return pItems[NextIndex(uCount)];
        }

        template<typename T>
        inline auto NextRange(T &items)
        {
            return NextIterator(items.begin(), items.end());
        }

        template<typename T>
        inline T &NextList(AuList<T> &items)
        {
            return *NextRange(items);
        }

        template<typename T>
        inline const T &NextList(const AuList<T> &items)
        {
            return *NextRange(items);
        }

        template<typename T>
        inline void ShuffleIterators(T begin, T end)
        {
            // Hitting TLS through the IAT is as dumb as throwing OOM to shuffle
            // DUMB either way
            AU_DEBUG_MEMCRUNCH;

            auto uCount = std::distance(begin, end);
            auto nextIndexArray = this->NextArrayU32RangeFast(uCount, 0, uCount - 1);
            
            for (AU_ITERATE_N(i, AuUInt(uCount)))
            {
                auto nextItrA = begin;
                auto nextItrB = begin;
                std::advance(nextItrA, i);
                std::advance(nextItrB, nextIndexArray[i]);
                AuSwap(*nextItrA, *nextItrB);
            }
        }

        template<typename T>
        inline void ShuffleList(AuList<T> &list)
        {
            this->ShuffleIterators(list.begin(), list.end());
        }
    };

    AUKN_SHARED_SOO2(Random, IRandomDevice, kSizeRNGDevice,
                     ((const RandomDef &, def)),
                     const RandomDef &def);
}