/****************************************************************************
* Copyright (C) 2014-2015 Intel Corporation.   All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
* @file backend.cpp
*
* @brief Backend handles rasterization, pixel shading and output merger
*        operations.
*
******************************************************************************/

#include <smmintrin.h>

#include "backend.h"
#include "backend_impl.h"
#include "tilemgr.h"
#include "memory/tilingtraits.h"
#include "core/multisample.h"

#include <algorithm>

template<SWR_FORMAT format>
void ClearRasterTile(uint8_t *pTileBuffer, simdvector &value)
{
    auto lambda = [&](int32_t comp)
    {
        FormatTraits<format>::storeSOA(comp, pTileBuffer, value.v[comp]);

        pTileBuffer += (KNOB_SIMD_WIDTH * FormatTraits<format>::GetBPC(comp) / 8);
    };

    const uint32_t numIter = (KNOB_TILE_Y_DIM / SIMD_TILE_Y_DIM) * (KNOB_TILE_X_DIM / SIMD_TILE_X_DIM);

    for (uint32_t i = 0; i < numIter; ++i)
    {
        UnrollerL<0, FormatTraits<format>::numComps, 1>::step(lambda);
    }
}

#if USE_8x2_TILE_BACKEND
template<SWR_FORMAT format>
void ClearRasterTile(uint8_t *pTileBuffer, simd16vector &value)
{
    auto lambda = [&](int32_t comp)
    {
        FormatTraits<format>::storeSOA(comp, pTileBuffer, value.v[comp]);

        pTileBuffer += (KNOB_SIMD16_WIDTH * FormatTraits<format>::GetBPC(comp) / 8);
    };

    const uint32_t numIter = (KNOB_TILE_Y_DIM / SIMD16_TILE_Y_DIM) * (KNOB_TILE_X_DIM / SIMD16_TILE_X_DIM);

    for (uint32_t i = 0; i < numIter; ++i)
    {
        UnrollerL<0, FormatTraits<format>::numComps, 1>::step(lambda);
    }
}

#endif
template<SWR_FORMAT format>
INLINE void ClearMacroTile(DRAW_CONTEXT *pDC, SWR_RENDERTARGET_ATTACHMENT rt, uint32_t macroTile, uint32_t renderTargetArrayIndex, DWORD clear[4], const SWR_RECT& rect)
{
    // convert clear color to hottile format
    // clear color is in RGBA float/uint32
#if USE_8x2_TILE_BACKEND
    simd16vector vClear;
    for (uint32_t comp = 0; comp < FormatTraits<format>::numComps; ++comp)
    {
        simd16scalar vComp;
        vComp = _simd16_load1_ps((const float*)&clear[comp]);
        if (FormatTraits<format>::isNormalized(comp))
        {
            vComp = _simd16_mul_ps(vComp, _simd16_set1_ps(FormatTraits<format>::fromFloat(comp)));
            vComp = _simd16_castsi_ps(_simd16_cvtps_epi32(vComp));
        }
        vComp = FormatTraits<format>::pack(comp, vComp);
        vClear.v[FormatTraits<format>::swizzle(comp)] = vComp;
    }

#else
    simdvector vClear;
    for (uint32_t comp = 0; comp < FormatTraits<format>::numComps; ++comp)
    {
        simdscalar vComp;
        vComp = _simd_load1_ps((const float*)&clear[comp]);
        if (FormatTraits<format>::isNormalized(comp))
        {
            vComp = _simd_mul_ps(vComp, _simd_set1_ps(FormatTraits<format>::fromFloat(comp)));
            vComp = _simd_castsi_ps(_simd_cvtps_epi32(vComp));
        }
        vComp = FormatTraits<format>::pack(comp, vComp);
        vClear.v[FormatTraits<format>::swizzle(comp)] = vComp;
    }

#endif
    uint32_t tileX, tileY;
    MacroTileMgr::getTileIndices(macroTile, tileX, tileY);

    // Init to full macrotile
    SWR_RECT clearTile =
    {
        KNOB_MACROTILE_X_DIM * int32_t(tileX),
        KNOB_MACROTILE_Y_DIM * int32_t(tileY),
        KNOB_MACROTILE_X_DIM * int32_t(tileX + 1),
        KNOB_MACROTILE_Y_DIM * int32_t(tileY + 1),
    };

    // intersect with clear rect
    clearTile &= rect;

    // translate to local hottile origin
    clearTile.Translate(-int32_t(tileX) * KNOB_MACROTILE_X_DIM, -int32_t(tileY) * KNOB_MACROTILE_Y_DIM);

    // Make maximums inclusive (needed for convert to raster tiles)
    clearTile.xmax -= 1;
    clearTile.ymax -= 1;

    // convert to raster tiles
    clearTile.ymin >>= (KNOB_TILE_Y_DIM_SHIFT);
    clearTile.ymax >>= (KNOB_TILE_Y_DIM_SHIFT);
    clearTile.xmin >>= (KNOB_TILE_X_DIM_SHIFT);
    clearTile.xmax >>= (KNOB_TILE_X_DIM_SHIFT);

    const int32_t numSamples = GetNumSamples(pDC->pState->state.rastState.sampleCount);
    // compute steps between raster tile samples / raster tiles / macro tile rows
    const uint32_t rasterTileSampleStep = KNOB_TILE_X_DIM * KNOB_TILE_Y_DIM * FormatTraits<format>::bpp / 8;
    const uint32_t rasterTileStep = (KNOB_TILE_X_DIM * KNOB_TILE_Y_DIM * (FormatTraits<format>::bpp / 8)) * numSamples;
    const uint32_t macroTileRowStep = (KNOB_MACROTILE_X_DIM / KNOB_TILE_X_DIM) * rasterTileStep;
    const uint32_t pitch = (FormatTraits<format>::bpp * KNOB_MACROTILE_X_DIM / 8);

    HOTTILE *pHotTile = pDC->pContext->pHotTileMgr->GetHotTile(pDC->pContext, pDC, macroTile, rt, true, numSamples, renderTargetArrayIndex);
    uint32_t rasterTileStartOffset = (ComputeTileOffset2D< TilingTraits<SWR_TILE_SWRZ, FormatTraits<format>::bpp > >(pitch, clearTile.xmin, clearTile.ymin)) * numSamples;
    uint8_t* pRasterTileRow = pHotTile->pBuffer + rasterTileStartOffset; //(ComputeTileOffset2D< TilingTraits<SWR_TILE_SWRZ, FormatTraits<format>::bpp > >(pitch, x, y)) * numSamples;

    // loop over all raster tiles in the current hot tile
    for (int32_t y = clearTile.ymin; y <= clearTile.ymax; ++y)
    {
        uint8_t* pRasterTile = pRasterTileRow;
        for (int32_t x = clearTile.xmin; x <= clearTile.xmax; ++x)
        {
            for( int32_t sampleNum = 0; sampleNum < numSamples; sampleNum++)
            {
                ClearRasterTile<format>(pRasterTile, vClear);
                pRasterTile += rasterTileSampleStep;
            }
        }
        pRasterTileRow += macroTileRowStep;
    }

    pHotTile->state = HOTTILE_DIRTY;
}


void ProcessClearBE(DRAW_CONTEXT *pDC, uint32_t workerId, uint32_t macroTile, void *pUserData)
{
    SWR_CONTEXT *pContext = pDC->pContext;

    if (KNOB_FAST_CLEAR)
    {
        CLEAR_DESC *pClear = (CLEAR_DESC*)pUserData;
        SWR_MULTISAMPLE_COUNT sampleCount = pDC->pState->state.rastState.sampleCount;
        uint32_t numSamples = GetNumSamples(sampleCount);

        SWR_ASSERT(pClear->attachmentMask != 0); // shouldn't be here without a reason.

        AR_BEGIN(BEClear, pDC->drawId);

        if (pClear->attachmentMask & SWR_ATTACHMENT_MASK_COLOR)
        {
            unsigned long rt = 0;
            uint32_t mask = pClear->attachmentMask & SWR_ATTACHMENT_MASK_COLOR;
            while (_BitScanForward(&rt, mask))
            {
                mask &= ~(1 << rt);

                HOTTILE *pHotTile = pContext->pHotTileMgr->GetHotTile(pContext, pDC, macroTile, (SWR_RENDERTARGET_ATTACHMENT)rt, true, numSamples, pClear->renderTargetArrayIndex);

                // All we want to do here is to mark the hot tile as being in a "needs clear" state.
                pHotTile->clearData[0] = *(DWORD*)&(pClear->clearRTColor[0]);
                pHotTile->clearData[1] = *(DWORD*)&(pClear->clearRTColor[1]);
                pHotTile->clearData[2] = *(DWORD*)&(pClear->clearRTColor[2]);
                pHotTile->clearData[3] = *(DWORD*)&(pClear->clearRTColor[3]);
                pHotTile->state = HOTTILE_CLEAR;
            }
        }

        if (pClear->attachmentMask & SWR_ATTACHMENT_DEPTH_BIT)
        {
            HOTTILE *pHotTile = pContext->pHotTileMgr->GetHotTile(pContext, pDC, macroTile, SWR_ATTACHMENT_DEPTH, true, numSamples, pClear->renderTargetArrayIndex);
            pHotTile->clearData[0] = *(DWORD*)&pClear->clearDepth;
            pHotTile->state = HOTTILE_CLEAR;
        }

        if (pClear->attachmentMask & SWR_ATTACHMENT_STENCIL_BIT)
        {
            HOTTILE *pHotTile = pContext->pHotTileMgr->GetHotTile(pContext, pDC, macroTile, SWR_ATTACHMENT_STENCIL, true, numSamples, pClear->renderTargetArrayIndex);

            pHotTile->clearData[0] = pClear->clearStencil;
            pHotTile->state = HOTTILE_CLEAR;
        }

        AR_END(BEClear, 1);
    }
    else
    {
        // Legacy clear
        CLEAR_DESC *pClear = (CLEAR_DESC*)pUserData;
        AR_BEGIN(BEClear, pDC->drawId);

        if (pClear->attachmentMask & SWR_ATTACHMENT_MASK_COLOR)
        {
            DWORD clearData[4];
            clearData[0] = *(DWORD*)&(pClear->clearRTColor[0]);
            clearData[1] = *(DWORD*)&(pClear->clearRTColor[1]);
            clearData[2] = *(DWORD*)&(pClear->clearRTColor[2]);
            clearData[3] = *(DWORD*)&(pClear->clearRTColor[3]);

            PFN_CLEAR_TILES pfnClearTiles = gClearTilesTable[KNOB_COLOR_HOT_TILE_FORMAT];
            SWR_ASSERT(pfnClearTiles != nullptr);

            unsigned long rt = 0;
            uint32_t mask = pClear->attachmentMask & SWR_ATTACHMENT_MASK_COLOR;
            while (_BitScanForward(&rt, mask))
            {
                mask &= ~(1 << rt);

                pfnClearTiles(pDC, (SWR_RENDERTARGET_ATTACHMENT)rt, macroTile, pClear->renderTargetArrayIndex, clearData, pClear->rect);
            }
        }

        if (pClear->attachmentMask & SWR_ATTACHMENT_DEPTH_BIT)
        {
            DWORD clearData[4];
            clearData[0] = *(DWORD*)&pClear->clearDepth;
            PFN_CLEAR_TILES pfnClearTiles = gClearTilesTable[KNOB_DEPTH_HOT_TILE_FORMAT];
            SWR_ASSERT(pfnClearTiles != nullptr);

            pfnClearTiles(pDC, SWR_ATTACHMENT_DEPTH, macroTile, pClear->renderTargetArrayIndex, clearData, pClear->rect);
        }

        if (pClear->attachmentMask & SWR_ATTACHMENT_STENCIL_BIT)
        {
            DWORD clearData[4];
            clearData[0] = pClear->clearStencil;
            PFN_CLEAR_TILES pfnClearTiles = gClearTilesTable[KNOB_STENCIL_HOT_TILE_FORMAT];

            pfnClearTiles(pDC, SWR_ATTACHMENT_STENCIL, macroTile, pClear->renderTargetArrayIndex, clearData, pClear->rect);
        }

        AR_END(BEClear, 1);
    }
}

void InitClearTilesTable()
{
    memset(gClearTilesTable, 0, sizeof(gClearTilesTable));

    gClearTilesTable[R8G8B8A8_UNORM]        = ClearMacroTile<R8G8B8A8_UNORM>;
    gClearTilesTable[B8G8R8A8_UNORM]        = ClearMacroTile<B8G8R8A8_UNORM>;
    gClearTilesTable[R32_FLOAT]             = ClearMacroTile<R32_FLOAT>;
    gClearTilesTable[R32G32B32A32_FLOAT]    = ClearMacroTile<R32G32B32A32_FLOAT>;
    gClearTilesTable[R8_UINT]               = ClearMacroTile<R8_UINT>;
}
