// Copyright (C) 2003-2009 Dolphin Project.

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License 2.0 for more details.

// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/

// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/

#include "Common.h"

#include "EfbInterface.h"
#include "BPMemLoader.h"
#include "LookUpTables.h"
#include "SWPixelEngine.h"


u8 efb[EFB_WIDTH*EFB_HEIGHT*6];


namespace EfbInterface
{
    u8 efbColorTexture[EFB_WIDTH*EFB_HEIGHT*4];

    inline u32 GetColorOffset(u16 x, u16 y)
    {
        return (x + y * EFB_WIDTH) * 3;
    }

    inline u32 GetDepthOffset(u16 x, u16 y)
    {
        return (x + y * EFB_WIDTH) * 3 + DEPTH_BUFFER_START;
    }

    void SetPixelAlphaOnly(u32 offset, u8 a)
    {
         switch (bpmem.zcontrol.pixel_format)
        {
        case PIXELFMT_RGB8_Z24:
        case PIXELFMT_Z24:
        case PIXELFMT_RGB565_Z16:
            // do nothing
            break;
        case PIXELFMT_RGBA6_Z24:
            {
				u32 a32 = a;
				u32 *dst = (u32*)&efb[offset];
				u32 val = *dst & 0xffffffc0;
				val |= (a32 >> 2) & 0x0000003f;
				*dst = val;
            }
            break;        
        default:
            ERROR_LOG(VIDEO, "Unsupported pixel format: %i", bpmem.zcontrol.pixel_format);
        }
    }

    void SetPixelColorOnly(u32 offset, u8 *rgb)
    {
        switch (bpmem.zcontrol.pixel_format)
        {
        case PIXELFMT_RGB8_Z24:
        case PIXELFMT_Z24:
            {
				u32 src = *(u32*)rgb;
				u32 *dst = (u32*)&efb[offset];
				u32 val = *dst & 0xff000000;
				val |= src >> 8;
				*dst = val;
            }
            break;
        case PIXELFMT_RGBA6_Z24:
            {
				u32 src = *(u32*)rgb;
				u32 *dst = (u32*)&efb[offset];
				u32 val = *dst & 0xff00003f;
				val |= (src >> 4) & 0x00000fc0;	// blue
				val |= (src >> 6) & 0x0003f000;	// green
				val |= (src >> 8) & 0x00fc0000;	// red
				*dst = val;
            }
            break;
        case PIXELFMT_RGB565_Z16:
            {
                INFO_LOG(VIDEO, "PIXELFMT_RGB565_Z16 is not supported correctly yet");
                u32 src = *(u32*)rgb;
				u32 *dst = (u32*)&efb[offset];
				u32 val = *dst & 0xff000000;
				val |= src >> 8;
				*dst = val;
            }
            break;
        default:
            ERROR_LOG(VIDEO, "Unsupported pixel format: %i", bpmem.zcontrol.pixel_format);
        }
    }

    void SetPixelAlphaColor(u32 offset, u8 *color)
    {
         switch (bpmem.zcontrol.pixel_format)
        {
        case PIXELFMT_RGB8_Z24:
        case PIXELFMT_Z24:
            {
                u32 src = *(u32*)color;
				u32 *dst = (u32*)&efb[offset];
				u32 val = *dst & 0xff000000;
				val |= src >> 8;
				*dst = val;
            }
            break;
        case PIXELFMT_RGBA6_Z24:
            {
				u32 src = *(u32*)color;
				u32 *dst = (u32*)&efb[offset];
				u32 val = *dst & 0xff000000;
				val |= (src >> 2) & 0x0000003f;	// alpha
				val |= (src >> 4) & 0x00000fc0;	// blue
				val |= (src >> 6) & 0x0003f000;	// green
				val |= (src >> 8) & 0x00fc0000;	// red
				*dst = val;
            }
            break;
        case PIXELFMT_RGB565_Z16:
            {
                INFO_LOG(VIDEO, "PIXELFMT_RGB565_Z16 is not supported correctly yet");
				u32 src = *(u32*)color;
				u32 *dst = (u32*)&efb[offset];
				u32 val = *dst & 0xff000000;
				val |= src >> 8;
				*dst = val;
            }
            break;
        default:
            ERROR_LOG(VIDEO, "Unsupported pixel format: %i", bpmem.zcontrol.pixel_format);
        }
    }

     void GetPixelColor(u32 offset, u8 *color)
    {
        switch (bpmem.zcontrol.pixel_format)
        {
        case PIXELFMT_RGB8_Z24:
        case PIXELFMT_Z24:
            {
    			u32 src = *(u32*)&efb[offset];
				u32 *dst = (u32*)color;
				u32 val = 0xff | ((src & 0x00ffffff) << 8);
				*dst = val;
            }
            break;
        case PIXELFMT_RGBA6_Z24:
            {
				u32 src = *(u32*)&efb[offset];
				color[ALP_C] = Convert6To8(src & 0x3f);
				color[BLU_C] = Convert6To8((src >> 6) & 0x3f);
				color[GRN_C] = Convert6To8((src >> 12) & 0x3f);
				color[RED_C] = Convert6To8((src >> 18) & 0x3f);
            }
            break;
        case PIXELFMT_RGB565_Z16:
            {
                INFO_LOG(VIDEO, "PIXELFMT_RGB565_Z16 is not supported correctly yet");
				u32 src = *(u32*)&efb[offset];
				u32 *dst = (u32*)color;
				u32 val = 0xff | ((src & 0x00ffffff) << 8);
				*dst = val;
            }
            break;
        default:
            ERROR_LOG(VIDEO, "Unsupported pixel format: %i", bpmem.zcontrol.pixel_format);
        }
    }

    void SetPixelDepth(u32 offset, u32 depth)
    {
        switch (bpmem.zcontrol.pixel_format)
        {
        case PIXELFMT_RGB8_Z24:
        case PIXELFMT_RGBA6_Z24:
        case PIXELFMT_Z24:
            {
    			u32 *dst = (u32*)&efb[offset];
				u32 val = *dst & 0xff000000;
				val |= depth & 0x00ffffff;
				*dst = val;				
            }
            break;
        case PIXELFMT_RGB565_Z16:
            {
                INFO_LOG(VIDEO, "PIXELFMT_RGB565_Z16 is not supported correctly yet");
				u32 *dst = (u32*)&efb[offset];
				u32 val = *dst & 0xff000000;
				val |= depth & 0x00ffffff;
				*dst = val;		
            }
            break;
        default:
            ERROR_LOG(VIDEO, "Unsupported pixel format: %i", bpmem.zcontrol.pixel_format);
        }        
    }

     u32 GetPixelDepth(u32 offset)
    {
        u32 depth = 0;

        switch (bpmem.zcontrol.pixel_format)
        {
        case PIXELFMT_RGB8_Z24:
        case PIXELFMT_RGBA6_Z24:
        case PIXELFMT_Z24:
            {
				depth = (*(u32*)&efb[offset]) & 0x00ffffff;
            }
            break;
        case PIXELFMT_RGB565_Z16:
            {
                INFO_LOG(VIDEO, "PIXELFMT_RGB565_Z16 is not supported correctly yet");
				depth = (*(u32*)&efb[offset]) & 0x00ffffff;
            }
            break;
        default:
            ERROR_LOG(VIDEO, "Unsupported pixel format: %i", bpmem.zcontrol.pixel_format);
        }

        return depth;
    }

    u32 GetSourceFactor(u8 *srcClr, u8 *dstClr, int mode)
    {
        switch (mode) {
            case 0:  // zero
                return 0;
            case 1:  // one
                return 0xffffffff;
            case 2:  // dstclr
                return *(u32*)dstClr;
            case 3:  // invdstclr
                return 0xffffffff - *(u32*)dstClr;                     
            case 4:  // srcalpha
                {
                    u8 alpha = srcClr[ALP_C];
                    u32 factor = alpha << 24 | alpha << 16 | alpha << 8 | alpha;
                    return factor;
                }
            case 5:  // invsrcalpha
                {
                    u8 alpha = 0xff - srcClr[ALP_C];
                    u32 factor = alpha << 24 | alpha << 16 | alpha << 8 | alpha;
                    return factor;
                }
            case 6:  // dstalpha
                {
                    u8 alpha = dstClr[ALP_C];
                    u32 factor = alpha << 24 | alpha << 16 | alpha << 8 | alpha;
                    return factor;
                }
            case 7:  // invdstalpha
                {
                    u8 alpha = 0xff - dstClr[ALP_C];
                    u32 factor = alpha << 24 | alpha << 16 | alpha << 8 | alpha;
                    return factor;
                }
        }

        return 0;
    }

    u32 GetDestinationFactor(u8 *srcClr, u8 *dstClr, int mode)
    {
        switch (mode) {
            case 0:  // zero
                return 0;
            case 1:  // one
                return 0xffffffff;
             case 2:  // srcclr
                return *(u32*)srcClr;
            case 3:  // invsrcclr
                return 0xffffffff - *(u32*)srcClr;            
            case 4:  // srcalpha
                {
                    u8 alpha = srcClr[ALP_C];
                    u32 factor = alpha << 24 | alpha << 16 | alpha << 8 | alpha;
                    return factor;
                }
            case 5:  // invsrcalpha
                {
                    u8 alpha = 0xff - srcClr[ALP_C];
                    u32 factor = alpha << 24 | alpha << 16 | alpha << 8 | alpha;
                    return factor;
                }
            case 6:  // dstalpha
                {
                    u8 alpha = dstClr[ALP_C] & 0xff;
                    u32 factor = alpha << 24 | alpha << 16 | alpha << 8 | alpha;
                    return factor;
                }
            case 7:  // invdstalpha
                {
                    u8 alpha = 0xff - dstClr[ALP_C];
                    u32 factor = alpha << 24 | alpha << 16 | alpha << 8 | alpha;
                    return factor;
                }
        }

        return 0;
    }

    void BlendColor(u8 *srcClr, u8 *dstClr)
    {
        u32 srcFactor = GetSourceFactor(srcClr, dstClr, bpmem.blendmode.srcfactor);
        u32 dstFactor = GetDestinationFactor(srcClr, dstClr, bpmem.blendmode.dstfactor);

        for (int i = 0; i < 4; i++)
        {
            // add MSB of factors to make their range 0 -> 256
            u32 sf = (srcFactor & 0xff);
            sf += sf >> 7;
            
            u32 df = (dstFactor & 0xff);
            df += df >> 7;

            u32 color = (srcClr[i] * sf + dstClr[i] * df) >> 8;
            dstClr[i] = (color>255)?255:color;

            dstFactor >>= 8;
            srcFactor >>= 8;
        }
    }

    void LogicBlend(u32 srcClr, u32 &dstClr, int op)
    {
        switch (op) {
            case 0:  // clear
                dstClr = 0;
                break;
            case 1:  // and
                dstClr = srcClr & dstClr;
                break;
            case 2:  // revand
                dstClr = srcClr & (~dstClr);
                break;
            case 3:  // copy
                dstClr = srcClr;
                break;
            case 4:  // invand
                dstClr = (~srcClr) & dstClr;
                break;
            case 5:  // noop
		// Do nothing
                break;
            case 6:  // xor
                dstClr = srcClr ^ dstClr;
                break;
            case 7:  // or
                dstClr = srcClr | dstClr;
                break;
            case 8:  // nor
                dstClr = ~(srcClr | dstClr);
                break;
            case 9:  // equiv
                dstClr = ~(srcClr ^ dstClr);
                break;
            case 10: // inv
                dstClr = ~dstClr;
                break;
            case 11: // revor
                dstClr = srcClr | (~dstClr);
                break;
            case 12: // invcopy
                dstClr = ~srcClr;
                break;
            case 13: // invor
                dstClr = (~srcClr) | dstClr;
                break;
            case 14: // nand
                dstClr = ~(srcClr & dstClr);
                break;
            case 15: // set
                dstClr = 0xffffffff;
                break;
        }
    }

    void SubtractBlend(u8 *srcClr, u8 *dstClr)
    {
        for (int i = 0; i < 4; i++)
        {
            int c = (int)dstClr[i] - (int)srcClr[i];
            dstClr[i] = (c < 0)?0:c;
        }
    }

    void BlendTev(u16 x, u16 y, u8 *color)
    {
        u32 dstClr;
        u32 offset = GetColorOffset(x, y);

        u8 *dstClrPtr = (u8*)&dstClr;

        GetPixelColor(offset, dstClrPtr);        

        if (bpmem.blendmode.blendenable)
        {
            if (bpmem.blendmode.subtract)
                SubtractBlend(color, dstClrPtr);
            else
                BlendColor(color, dstClrPtr);
        }
        else if (bpmem.blendmode.logicopenable)
            LogicBlend(*((u32*)color), dstClr, bpmem.blendmode.logicmode);
        else
            dstClrPtr = color;

        if (bpmem.dstalpha.enable)
            dstClrPtr[ALP_C] = bpmem.dstalpha.alpha;

		if (bpmem.blendmode.colorupdate)
        {
            if (bpmem.blendmode.alphaupdate)
                SetPixelAlphaColor(offset, dstClrPtr);
            else
                SetPixelColorOnly(offset, dstClrPtr);
        }
        else if (bpmem.blendmode.alphaupdate)
            SetPixelAlphaOnly(offset, dstClrPtr[ALP_C]);

        // branchless bounding box update
        SWPixelEngine::pereg.boxLeft = SWPixelEngine::pereg.boxLeft>x?x:SWPixelEngine::pereg.boxLeft;
        SWPixelEngine::pereg.boxRight = SWPixelEngine::pereg.boxRight<x?x:SWPixelEngine::pereg.boxRight;
        SWPixelEngine::pereg.boxTop = SWPixelEngine::pereg.boxTop>y?y:SWPixelEngine::pereg.boxTop;
        SWPixelEngine::pereg.boxBottom = SWPixelEngine::pereg.boxBottom<y?y:SWPixelEngine::pereg.boxBottom;
    }

    void SetColor(u16 x, u16 y, u8 *color)
    {
        u32 offset = GetColorOffset(x, y);
        if (bpmem.blendmode.colorupdate)
        {
            if (bpmem.blendmode.alphaupdate)
                SetPixelAlphaColor(offset, color);
            else
                SetPixelColorOnly(offset, color);
        }
        else if (bpmem.blendmode.alphaupdate)
            SetPixelAlphaOnly(offset, color[ALP_C]);
    }

    void SetDepth(u16 x, u16 y, u32 depth)
    {
        SetPixelDepth(GetDepthOffset(x, y), depth);
    }

    void GetColor(u16 x, u16 y, u8 *color)
    {
        u32 offset = GetColorOffset(x, y);
        GetPixelColor(offset, color);
    }

    u32 GetDepth(u16 x, u16 y)
    {
        u32 offset = GetDepthOffset(x, y);
        return GetPixelDepth(offset);        
    }

    u8 *GetPixelPointer(u16 x, u16 y, bool depth)
    {
        if (depth)
            return &efb[GetDepthOffset(x, y)];
        return &efb[GetColorOffset(x, y)];
    }

    void UpdateColorTexture()
    {
        u32 color;
		u8* colorPtr = (u8*)&color;
		u32* texturePtr = (u32*)efbColorTexture;
        u32 textureAddress = 0;
        u32 efbOffset = 0;
        
        for (u16 y = 0; y < EFB_HEIGHT; y++)
        {
            for (u16 x = 0; x < EFB_WIDTH; x++)
            {
                GetPixelColor(efbOffset, colorPtr);
                efbOffset += 3;
				texturePtr[textureAddress++] = Common::swap32(color);  // ABGR->RGBA
            }
        }
    }

    bool ZCompare(u16 x, u16 y, u32 z)
    {
        u32 offset = GetDepthOffset(x, y);        
        u32 depth = GetPixelDepth(offset);

        bool pass;

        switch (bpmem.zmode.func)
        {
            case COMPARE_NEVER:
                pass = false;
                break;
            case COMPARE_LESS:
                pass = z < depth;
                break;
            case COMPARE_EQUAL:
                pass = z == depth;
                break;
            case COMPARE_LEQUAL:
                pass = z <= depth;
                break;
            case COMPARE_GREATER:
                pass = z > depth;
                break;
            case COMPARE_NEQUAL:
                pass = z != depth;
                break;
            case COMPARE_GEQUAL:
                pass = z >= depth;
                break;
            case COMPARE_ALWAYS:
                pass = true;
                break;
            default:
                pass = false;
                ERROR_LOG(VIDEO, "Bad Z compare mode %i", bpmem.zmode.func);
        }

        if (pass && bpmem.zmode.updateenable)
        {
            SetPixelDepth(offset, z);
        }
    
        return pass;
    }
}