//DL facts:
//	Ikaruga uses NO display lists!
//  Zelda WW uses TONS of display lists
//  Zelda TP uses almost 100% display lists except menus (we like this!)

// Note that it IS NOT POSSIBLE to precompile display lists! You can compile them as they are
// and hope that the vertex format doesn't change, though, if you do it just when they are 
// called. The reason is that the vertex format affects the sizes of the vertices.


#include "D3DBase.h"

#include "Common.h"
#include "Globals.h"
#include "VertexHandler.h"
#include "TransformEngine.h"
#include "OpcodeDecoding.h"
#include "TextureCache.h"
#include "ShaderManager.h"
#include "DecodedVArray.h"

#include "BPStructs.h"
#include "XFStructs.h"
#include "Utils.h"
#include "main.h"
#include "DataReader.h"

#include "DLCompiler.h"

#define CMDBUFFER_SIZE 1024*1024
DecodedVArray tempvarray;
void Decode();

extern u8 FAKE_PeekFifo8(u32 _uOffset);
extern u16 FAKE_PeekFifo16(u32 _uOffset);
extern u32 FAKE_PeekFifo32(u32 _uOffset);
extern int FAKE_GetFifoSize();

CDataReader_Fifo g_fifoReader;

void ExecuteDisplayList(u32 address, u32 size)
{
    IDataReader* pOldReader = g_pDataReader;

//	address &= 0x01FFFFFF; // phys address
	CDataReader_Memory memoryReader(address);
	g_pDataReader = &memoryReader;

	while((memoryReader.GetReadAddress() - address) < size)
	{
		Decode();
	}
	INCSTAT(stats.numDListsAlive);
	// reset to the old reader
	g_pDataReader = pOldReader;
}

inline u8 PeekFifo8(u32 _uOffset)
{
	return FAKE_PeekFifo8(_uOffset);
}

inline u16 PeekFifo16(u32 _uOffset)
{
	return FAKE_PeekFifo16(_uOffset);
}

inline u32 PeekFifo32(u32 _uOffset)
{
	return FAKE_PeekFifo32(_uOffset);
}


bool FifoCommandRunnable(void)
{
	u32 iBufferSize = FAKE_GetFifoSize();
	if (iBufferSize == 0)
		return false;

	u8 Cmd = PeekFifo8(0);	
	u32 iCommandSize = 0;

	switch(Cmd)
	{
	case GX_NOP:
		// Hm, this means that we scan over nop streams pretty slowly...
		iCommandSize = 1;
		break;

	case GX_LOAD_CP_REG:
		iCommandSize = 6;
		break;

	case GX_LOAD_INDX_A:
	case GX_LOAD_INDX_B:
	case GX_LOAD_INDX_C:
	case GX_LOAD_INDX_D:
		iCommandSize = 5;
		break;

	case GX_CMD_CALL_DL:	
		iCommandSize = 9;
		break;

	case 0x44:
		iCommandSize = 1;
		// zelda 4 swords calls it and checks the metrics registers after that
		break;

	case GX_CMD_INVL_VC: // invalid vertex cache - no parameter?
		iCommandSize = 1;
		break;

	case GX_LOAD_BP_REG:	
		iCommandSize = 5;
		break;

	case GX_LOAD_XF_REG:
		{
			// check if we can read the header
			if (iBufferSize >= 5)
			{				
				iCommandSize = 1 + 4;
				u32 Cmd2 = PeekFifo32(1);
				int dwTransferSize = ((Cmd2 >> 16) & 15) + 1;
				iCommandSize += dwTransferSize * 4;				
			}
			else
			{
				return false;
			}			
		}
		break;

	default:
		if (Cmd&0x80)
		{				
			// check if we can read the header
			if (iBufferSize >= 3)
			{
				iCommandSize = 1 + 2;
				u16 numVertices = PeekFifo16(1);
				VertexLoader& vtxLoader = g_VertexLoaders[Cmd & GX_VAT_MASK];
				vtxLoader.Setup();
				int vsize = vtxLoader.GetVertexSize();
				iCommandSize += numVertices * vsize;				
			}
			else
			{				
				return false;
			}
		}
		else
		{
			char szTemp[512];
			sprintf(szTemp, "Error: Unknown Opcode (0x%x)", Cmd);
			MessageBox(NULL, szTemp, "Video-Plugin", MB_OK);			
			g_VideoInitialize.pLog(szTemp, TRUE);
		}
		break;
	}
	
	if (iCommandSize > iBufferSize)
		return false;

#ifdef _DEBUG
	char temp[256];
	sprintf(temp, "OP detected: Cmd 0x%x  size %i  buffer %i",Cmd, iCommandSize, iBufferSize);
	g_VideoInitialize.pLog(temp, FALSE);
#endif

	return true;
}

void Decode(void)
{
    static int DecoderCount = 0;
    DecoderCount++;

    if (DecoderCount == 0x0019c601)
    {
        int i = 0;
    }

    // 0x0019c603  <- error 

    int Cmd = g_pDataReader->Read8();
	switch(Cmd)
	{
	case GX_NOP:
		break;

	case GX_LOAD_CP_REG: //0x08
		{
			u32 SubCmd = g_pDataReader->Read8();
			u32 Value = g_pDataReader->Read32();
			LoadCPReg(SubCmd,Value);
		}
		break;

	case GX_LOAD_XF_REG:
		{
			u32 test = PeekFifo32(0);
			u32 Cmd2 = g_pDataReader->Read32();
			
			int dwTransferSize = ((Cmd2>>16)&15) + 1;
			DWORD dwAddress = Cmd2 & 0xFFFF;
			static u32 pData[16];
			for (int i=0; i<dwTransferSize; i++)
				pData[i] = g_pDataReader->Read32();
			LoadXFReg(dwTransferSize,dwAddress,pData);
		}
		break;

	case GX_LOAD_INDX_A: //used for position matrices
		LoadIndexedXF(g_pDataReader->Read32(),0xC);
		break;
	case GX_LOAD_INDX_B: //used for normal matrices
		LoadIndexedXF(g_pDataReader->Read32(),0xD);
		break;
	case GX_LOAD_INDX_C: //used for postmatrices
		LoadIndexedXF(g_pDataReader->Read32(),0xE);
		break;
	case GX_LOAD_INDX_D: //used for lights
		LoadIndexedXF(g_pDataReader->Read32(),0xF);
		break;

	case GX_CMD_CALL_DL:
		{
			u32 dwAddr  = g_pDataReader->Read32();
			u32 dwCount = g_pDataReader->Read32();
			ExecuteDisplayList(dwAddr, dwCount);
		}			
		break;

	case 0x44:
		// zelda 4 swords calls it and checks the metrics registers after that
		break;

	case GX_CMD_INVL_VC:// Invalidate	(vertex cache?)	
		DebugLog("Invalidate	(vertex cache?)");
		break;

	case GX_LOAD_BP_REG: //0x61
		{
			u32 cmd = g_pDataReader->Read32();
			LoadBPReg(cmd);
		}
		break;

	// draw primitives 
	default:
		if (Cmd&0x80)
		{			
			// load vertices
			u16 numVertices = g_pDataReader->Read16();			
			tempvarray.Reset();
			VertexLoader::SetVArray(&tempvarray);
			VertexLoader& vtxLoader = g_VertexLoaders[Cmd & GX_VAT_MASK];
			vtxLoader.Setup();
			vtxLoader.PrepareRun();
			int vsize = vtxLoader.GetVertexSize();
			vtxLoader.RunVertices(numVertices);

			// draw vertices
			int primitive = (Cmd & GX_PRIMITIVE_MASK) >> GX_PRIMITIVE_SHIFT;
			CVertexHandler::DrawVertices(primitive, numVertices, &tempvarray);
		}
		else
		{
			char szTmp[256];
			// sprintf(szTmp, "Illegal command %02x (at %08x)",Cmd,g_pDataReader->GetPtr());
            sprintf(szTmp, "Illegal command %02x",Cmd);
			g_VideoInitialize.pLog(szTmp, TRUE);
			MessageBox(0,szTmp,"GFX ERROR",0);
			// _assert_msg_(0,szTmp,"");
			break;
		}
		break;
	}
}

void OpcodeDecoder_Init()
{	
	g_pDataReader = &g_fifoReader;
	tempvarray.Create(65536*3, 1, 8, 3, 2, 8);
}


void OpcodeDecoder_Shutdown()
{
	//VirtualFree((LPVOID)buffer,CMDBUFFER_SIZE,MEM_RELEASE);
	tempvarray.Destroy();
}

void OpcodeDecoder_Run()
{
	// just a small check
	if (g_pDataReader != &g_fifoReader)
	{
		MessageBox(NULL, "very strange", "video-plugin", MB_OK);
	}

    DVSTARTPROFILE();

	while (FifoCommandRunnable())
	{
		Decode();
	}
}