#include <assert.h>
#include "MpegVideoState.h"
#include "VideoStream_ReadDct.h"
#include "MPEG2/DctCoefficientTable0.h"
#include "MPEG2/DctCoefficientTable1.h"
#include "../../../Source/Log.h"
#include "LogSettings.h"

using namespace VideoStream;

ReadDct::ReadDct()
    : m_coeffTable(NULL)
    , m_block(NULL)
{
}

ReadDct::~ReadDct()
{
}

void ReadDct::Reset()
{
	m_programState = STATE_INIT;
	m_coeffTable = NULL;
	m_blockIndex = 0;
}

void ReadDct::SetBlockInfo(int16* block, unsigned int channel)
{
	m_channel = channel;
	m_block = block;
}

void ReadDct::Execute(void* context, Framework::CBitStream& stream)
{
	MPEG_VIDEO_STATE* state(reinterpret_cast<MPEG_VIDEO_STATE*>(context));
	PICTURE_HEADER& pictureHeader(state->pictureHeader);
	PICTURE_CODING_EXTENSION& pictureCodingExtension(state->pictureCodingExtension);
	BLOCK_DECODER_STATE& decoderState(state->blockDecoderState);
	SEQUENCE_HEADER& sequenceHeader(state->sequenceHeader);
	bool isMpeg2 = sequenceHeader.isMpeg2;

	while(1)
	{
		switch(m_programState)
		{
		case STATE_INIT:
			goto Label_Init;
		case STATE_READDCDIFFERENTIAL:
			goto Label_ReadDcDifferential;
		case STATE_CHECKEOB:
			goto Label_CheckEob;
		case STATE_READCOEFF:
			goto Label_ReadCoeff;
		case STATE_SKIPEOB:
			goto Label_SkipEob;
		default:
			assert(0);
		}

	Label_Init:
	{
#ifdef _DECODE_LOGGING
		static int currentBlockIndex = 0;
		CLog::GetInstance().Print(DECODE_LOG_NAME, "Block(%d) = ", currentBlockIndex++);
#endif
		bool isIntra = (pictureHeader.pictureCodingType == PICTURE_TYPE_I || decoderState.macroblockType & MACROBLOCK_MODE_INTRA);

		m_dcDiffReader.Reset();
		if(pictureCodingExtension.intraVlcFormat && isIntra)
		{
			m_coeffTable = &MPEG2::CDctCoefficientTable1::GetInstance();
		}
		else
		{
			m_coeffTable = &MPEG2::CDctCoefficientTable0::GetInstance();
		}

		if(isIntra)
		{
			m_programState = STATE_READDCDIFFERENTIAL;
		}
		else
		{
			m_programState = STATE_CHECKEOB;
		}
	}
		continue;

	Label_ReadDcDifferential:
		m_dcDiffReader.SetChannel(m_channel);
		m_dcDiffReader.Execute(context, stream);
		m_block[0] = static_cast<int16>(decoderState.dcPredictor[m_channel] + decoderState.dcDifferential);
		decoderState.dcPredictor[m_channel] = m_block[0];
#ifdef _DECODE_LOGGING
		CLog::GetInstance().Print(DECODE_LOG_NAME, "[%d]: %d ", 0, m_block[0]);
#endif
		m_blockIndex++;
		m_programState = STATE_CHECKEOB;
		continue;

	Label_CheckEob:
		if((m_blockIndex != 0) && m_coeffTable->IsEndOfBlock(&stream))
		{
			m_programState = STATE_SKIPEOB;
		}
		else
		{
			m_programState = STATE_READCOEFF;
		}
		continue;

	Label_ReadCoeff:
	{
		MPEG2::RUNLEVELPAIR runLevelPair;
		if(m_blockIndex == 0)
		{
			m_coeffTable->GetRunLevelPairDc(&stream, &runLevelPair, isMpeg2);
		}
		else
		{
			m_coeffTable->GetRunLevelPair(&stream, &runLevelPair, isMpeg2);
		}
		m_blockIndex += runLevelPair.run;

		if(m_blockIndex < 0x40)
		{
			m_block[m_blockIndex] = static_cast<int16>(runLevelPair.level);
#ifdef _DECODE_LOGGING
			CLog::GetInstance().Print(DECODE_LOG_NAME, "[%d]: %d ", m_blockIndex, runLevelPair.level);
#endif
		}
		else
		{
			assert(0);
			break;
		}

		m_blockIndex++;
		m_programState = STATE_CHECKEOB;
	}
		continue;

	Label_SkipEob:
		m_coeffTable->SkipEndOfBlock(&stream);
#ifdef _DECODE_LOGGING
		CLog::GetInstance().Print(DECODE_LOG_NAME, "\r\n");
#endif
		return;
	}
}