// Filename:-	cl_mp3.cpp
//
// (The interface module between all the MP3 stuff and Trek)
//
#include "client.h"
#include "cl_mp3.h"					//(only included directly from snd_mem.cpp, so not in client.h)
#include "../mp3code/mp3struct.h"	// keep this rather awful file secret from the rest of the program

// call the real worker code in the messy C stuff...
//
#ifdef __cplusplus
extern "C"
{
#endif

char*	C_MP3_IsValid			(void *pvData, int iDataLen);
char*	C_MP3_GetUnpackedSize	(void *pvData, int iDataLen, int *piUnpackedSize);
char*	C_MP3_UnpackRawPCM		(void *pvData, int iDataLen, int *piUnpackedSize, void *pbUnpackBuffer);
char*	C_MP3_GetHeaderData		(void *pvData, int iDataLen, int *piRate, int *piWidth, int *piChannels);
char*	C_MP3Stream_DecodeInit	(LP_MP3STREAM pSFX_MP3Stream, void *pvSourceData, int iSourceBytesRemaining,
								int iGameAudioSampleRate, int iGameAudioSampleBits );
unsigned int C_MP3Stream_Decode	(LP_MP3STREAM pSFX_MP3Stream);
char*	C_MP3Stream_Rewind		(LP_MP3STREAM pSFX_MP3Stream);


// these two are temp and will eventually be deleted... honest...
//
char*	C_TEST_MP3_GetUnpackedSize( const char *_FILENAME1, const char *_FILENAME2, const char *_FILENAME3,
									void *data1,void *data2,void *data3,
									int size1,int size2,int size3,
									int *iUnpackedSize1,int *iUnpackedSize2,int *iUnpackedSize3
									);
char *	C_TEST_MP3_UnpackRawPCM(const char *_FILENAME1, const char *_FILENAME2, const char *_FILENAME3,
								void *data1,void *data2,void *data3,
								int iSourceBytesRemaining1,int iSourceBytesRemaining2,int iSourceBytesRemaining3,
								int *piUnpackedSize1,int *piUnpackedSize2,int *piUnpackedSize3,
								void *pbUnpackBuffer1,void *pbUnpackBuffer2,void *pbUnpackBuffer3
								);


#ifdef __cplusplus
}
#endif



// expects data already loaded, filename arg is for error printing only
//
// returns success/fail
//
qboolean MP3_IsValid( const char *psLocalFilename, void *pvData, int iDataLen )
{
	char *psError = C_MP3_IsValid(pvData, iDataLen);

	if (psError)
	{
		Com_Printf(va(S_COLOR_RED"%s\n(File: %s)\n",psError, psLocalFilename));
	}

	return !psError;
}



// expects data already loaded, filename arg is for error printing only
//
// returns unpacked length, or 0 for errors (which will be printed internally)
//
int MP3_GetUnpackedSize( const char *psLocalFilename, void *pvData, int iDataLen, qboolean qbIgnoreID3Tag /* = qfalse */)
{
	int	iUnpackedSize = 0;
	
	if (qbIgnoreID3Tag || !MP3_ReadSpecialTagInfo((byte *)pvData, iDataLen, NULL, &iUnpackedSize))
	{	
		char *psError = C_MP3_GetUnpackedSize( pvData, iDataLen, &iUnpackedSize);

		if (psError)
		{
			Com_Printf(va(S_COLOR_RED"%s\n(File: %s)\n",psError, psLocalFilename));
			return 0;
		}
	}	

	return iUnpackedSize;
}



// expects data already loaded, filename arg is for error printing only
//
// returns byte count of unpacked data (effectively a success/fail bool)
//
int MP3_UnpackRawPCM( const char *psLocalFilename, void *pvData, int iDataLen, byte *pbUnpackBuffer )
{
	int iUnpackedSize;
	char *psError = C_MP3_UnpackRawPCM( pvData, iDataLen, &iUnpackedSize, pbUnpackBuffer);

	if (psError)
	{
		Com_Printf(va(S_COLOR_RED"%s\n(File: %s)\n",psError, psLocalFilename));
		return 0;
	}

	return iUnpackedSize;
}



// expects data already loaded, filename arg is for error printing only
//
qboolean MP3_FakeUpWAVInfo( const char *psLocalFilename, void *pvData, int iDataLen, int iUnpackedDataLength, int &format, int &rate, int &width, int &channels, int &samples, int &dataofs)
{
	// some things can be done instantly...
	//
	format = 1;		// 1 for MS format
	dataofs= 0;		// will be 0 for me (since there's no header in the unpacked data)

	// some things need to be read...
	//
	char *psError = C_MP3_GetHeaderData(pvData, iDataLen, &rate, &width, &channels);
	if (psError)
	{
		Com_Printf(va(S_COLOR_RED"%s\n(File: %s)\n",psError, psLocalFilename));
	}

	// and some stuff needs calculating...
	//
	samples	= iUnpackedDataLength / width;
		

	return !psError;

}



const char sKEY_MAXVOL[]="#MAXVOL";	// formerly #defines
const char sKEY_UNCOMP[]="#UNCOMP";	//    "        "

// returns qtrue for success...
//
qboolean MP3_ReadSpecialTagInfo(byte *pbLoadedFile, int iLoadedFileLen,		// (in)
								id3v1_1** ppTAG,							// (out), can be NULL
								int *piUncompressedSize, float *pfMaxVol	// (out), can be NULL
								)
{
	qboolean qbError = qfalse;

	id3v1_1* pTAG = (id3v1_1*) ((pbLoadedFile+iLoadedFileLen)-sizeof(id3v1_1));	// sizeof = 128	

	if (!strncmp(pTAG->id, "TAG", 3))
	{
		// TAG found...
		//
		
		// read MAXVOL key...
		//
		if (strncmp(pTAG->comment, sKEY_MAXVOL,	strlen(sKEY_MAXVOL)))
		{
			qbError = qtrue;
		}
		else
		{
			if ( pfMaxVol)
			{
				*pfMaxVol = atof(pTAG->comment + strlen(sKEY_MAXVOL));
			}
		}

		//
		// read UNCOMP key...
		//
		if (strncmp(pTAG->album, sKEY_UNCOMP, strlen(sKEY_UNCOMP)))
		{
			qbError = qtrue;
		}
		else
		{
			if ( piUncompressedSize)
			{
				*piUncompressedSize = atoi(pTAG->album + strlen(sKEY_UNCOMP));
			}
		}
	}
	else
	{
		pTAG = NULL;
	}

	if (ppTAG)
	{
		*ppTAG = pTAG;
	}

	return (pTAG && !qbError);
}



qboolean TEST_MP3_GetUnpackedSize(const char *_FILENAME1, const char *_FILENAME2, const char *_FILENAME3,
										void *data1,void *data2,void *data3,
										int size1,int size2,int size3,
										int *iUnpackedSize1,int *iUnpackedSize2,int *iUnpackedSize3
										)
{
	char *psError = C_TEST_MP3_GetUnpackedSize(_FILENAME1, _FILENAME2, _FILENAME3,
												data1,data2,data3,
												size1,size2,size3,
												iUnpackedSize1,iUnpackedSize2,iUnpackedSize3
												);

	if (psError)
	{
		Com_Printf(va(S_COLOR_RED"%s\n",psError));
		return qfalse;
	}

	return qtrue;
}


// expects data already loaded, filename arg is for error printing only
//
// returns byte count of unpacked data (effectively a success/fail bool)
//
qboolean TEST_MP3_UnpackRawPCM(		const char *_FILENAME1, const char *_FILENAME2, const char *_FILENAME3,
									void *data1,void *data2,void *data3,
									int iSourceBytesRemaining1,int iSourceBytesRemaining2,int iSourceBytesRemaining3,
									int *piUnpackedSize1,int *piUnpackedSize2,int *piUnpackedSize3,
									void *pbUnpackBuffer1,void *pbUnpackBuffer2,void *pbUnpackBuffer3
									)
{
	char *psError = C_TEST_MP3_UnpackRawPCM(_FILENAME1, _FILENAME2, _FILENAME3,
											data1,data2,data3,
											iSourceBytesRemaining1,iSourceBytesRemaining2,iSourceBytesRemaining3,
											piUnpackedSize1,piUnpackedSize2,piUnpackedSize3,
											pbUnpackBuffer1,pbUnpackBuffer2,pbUnpackBuffer3
											);
	if (psError)
	{
		Com_Printf(va(S_COLOR_RED"%s\n",psError));
		return qfalse;
	}

	return qtrue;
}





// a file has been loaded in memory, see if we want to keep it as MP3, else as normal WAV...
//
// return = qtrue if keeping as MP3
//
// (note: the reason I pass in the unpacked size rather than working it out here is simply because I already have it)
//
qboolean MP3Stream_InitFromFile( sfx_t* sfx, byte *pbSrcData, int iSrcDatalen, const char *psSrcDataFilename, int iMP3UnPackedSize )
{
	// first, make a decision based on size here as to whether or not it's worth it because of MP3 buffer space
	//	making small files much bigger (and therefore best left as WAV)...
	//
#define FUZZY_AMOUNT (5*1024)	// so it has to be significantly over, not just break even, because of
								// the xtra CPU time versus memory saving

	if (iSrcDatalen + sizeof(MP3STREAM) + FUZZY_AMOUNT < iMP3UnPackedSize)
	{
		// ok, let's keep it as MP3 then...
		//

		float fMaxVol = 128;	// seems to be a reasonable typical default for maxvol (for lip synch). Naturally there's no #define I can use instead...

		MP3_ReadSpecialTagInfo(pbSrcData, iSrcDatalen, NULL, NULL, &fMaxVol );	// try and read a read maxvol from MP3 header
	
		// fill in some sfx_t fields...
		//
					sfx->eCompressionType = ct_MP3;
					sfx->data			  = (byte*) Hunk_Alloc( iSrcDatalen );	// will err_drop if fails
		memcpy	  ( sfx->data, pbSrcData, iSrcDatalen );						// ... so the -> data field is MP3, not PCM		
					sfx->width  = 2;//(s_compression->value == 1)?1:2;						
					sfx->length = (iMP3UnPackedSize / sfx->width) / (44100 / dma.speed);
					sfx->vol_range = fMaxVol;

		// now init the low-level MP3 stuff...
		//		
		MP3STREAM SFX_MP3Stream = {0};
		char *psError = C_MP3Stream_DecodeInit( &SFX_MP3Stream, sfx->data, iSrcDatalen,
												dma.speed,//(s_khz->value == 44)?44100:(s_khz->value == 22)?22050:11025,
												sfx->width * 8
												);
		if (psError)
		{
			// This should never happen, since any errors or problems with the MP3 file would have stopped us getting
			//	to this whole function, but just in case...
			//
			Com_Printf(va(S_COLOR_YELLOW"File \"%s\": %s\n",psSrcDataFilename,psError));

			// This will leave iSrcDatalen bytes on the hunk stack (since you can't dealloc that), but MP3 files are
			//	usually small, and like I say, it should never happen.
			//
			// Strictly speaking, I should do a Z_Malloc above, then I could do a Z_Free if failed, else do a Hunk_Alloc
			//	to copy the Z_Malloc data into, then Z_Free, but for something that shouldn't happen it seemed bad to
			//	penalise the rest of the game with extra malloc demands.
			//
			return qfalse;	
		}

		// success ( ...on a plate).
		//
		// make a copy of the filled-in stream struct and attach to the sfx_t struct...
		//
				sfx->pMP3StreamHeader = (MP3STREAM *) Hunk_Alloc( sizeof(MP3STREAM) );
		memcpy(	sfx->pMP3StreamHeader, &SFX_MP3Stream,			  sizeof(MP3STREAM) );
		//
		return qtrue;
	}

	return qfalse;
}


// return is decoded byte count, else 0 for finished
//
int MP3Stream_Decode( LP_MP3STREAM lpMP3Stream )
{
	lpMP3Stream->iCopyOffset = 0;
	return C_MP3Stream_Decode( lpMP3Stream );
}

// returns qtrue for all ok
//
// (this can be optimised by copying the whole header from the sfx struct sometime)
//
qboolean MP3Stream_Rewind( channel_t *ch )
{		
/*	char *psError = C_MP3Stream_Rewind( lpMP3Stream );

	if (psError)
	{
		Com_Printf(S_COLOR_YELLOW"%s\n",psError);
		return qfalse;
	}

	return qtrue;
*/
	memcpy(&ch->MP3StreamHeader, ch->sfx->pMP3StreamHeader, sizeof(ch->MP3StreamHeader));
	return qtrue;
}

void MP3Stream_GetSamples( channel_t *ch, int startingSampleNum, int count, short *buf )
{	
	static const int iQuarterOfSlidingBuffer		=  sizeof(ch->MP3SlidingDecodeBuffer)/4;
	static const int iThreeQuartersOfSlidingBuffer	= (sizeof(ch->MP3SlidingDecodeBuffer)*3)/4;

//	Com_Printf("startingSampleNum %d\n",startingSampleNum);

	count *= ch->sfx->width;	// count arg was for words, so double it for bytes;

	startingSampleNum *= ch->sfx->width;

	if ( startingSampleNum < ch->iMP3SlidingDecodeWindowPos)
	{
		// what?!?!?!   Fucking time travel needed or something?, forget it
		memset(buf,0,count);
		return;
	}

//	OutputDebugString(va("\nRequest: startingSampleNum %d, count %d\n",startingSampleNum,count));
//	OutputDebugString(va("WindowPos %d, WindowWritePos %d\n",ch->iMP3SlidingDecodeWindowPos,ch->iMP3SlidingDecodeWritePos));

	while (!
		(
			(startingSampleNum			>= ch->iMP3SlidingDecodeWindowPos)
			&&
			(startingSampleNum + count	<  ch->iMP3SlidingDecodeWindowPos + ch->iMP3SlidingDecodeWritePos)
			)
			)
	{
//		OutputDebugString("Scrolling...");

		int _iBytesDecoded = MP3Stream_Decode( (LP_MP3STREAM) &ch->MP3StreamHeader );
//		OutputDebugString(va("%d bytes decoded\n",_iBytesDecoded));
		if (_iBytesDecoded == 0)
		{
			// no more source data left so clear the remainder of the buffer...
			//
			memset(ch->MP3SlidingDecodeBuffer + ch->iMP3SlidingDecodeWritePos, 0, sizeof(ch->MP3SlidingDecodeBuffer)-ch->iMP3SlidingDecodeWritePos);
			//MP3Stream_Rewind(ch);	// should I do this???
//			OutputDebugString("Finished\n");
			break;
		}
		else
		{
			memcpy(ch->MP3SlidingDecodeBuffer + ch->iMP3SlidingDecodeWritePos,ch->MP3StreamHeader.bDecodeBuffer,_iBytesDecoded);

			ch->iMP3SlidingDecodeWritePos += _iBytesDecoded;

			// if reached 3/4 of buffer pos, backscroll the decode window by one quarter...
			//
			if (ch->iMP3SlidingDecodeWritePos > (sizeof(ch->MP3SlidingDecodeBuffer)*3)/4)
			{
				memmove(ch->MP3SlidingDecodeBuffer, ((byte *)ch->MP3SlidingDecodeBuffer + (sizeof(ch->MP3SlidingDecodeBuffer)/4)), (sizeof(ch->MP3SlidingDecodeBuffer)*3)/4);
				ch->iMP3SlidingDecodeWritePos -= sizeof(ch->MP3SlidingDecodeBuffer)/4;
				ch->iMP3SlidingDecodeWindowPos+= sizeof(ch->MP3SlidingDecodeBuffer)/4;
			}
		}
//		OutputDebugString(va("WindowPos %d, WindowWritePos %d\n",ch->iMP3SlidingDecodeWindowPos,ch->iMP3SlidingDecodeWritePos));
	}

	assert(startingSampleNum >= ch->iMP3SlidingDecodeWindowPos);
	memcpy( buf, ch->MP3SlidingDecodeBuffer + (startingSampleNum-ch->iMP3SlidingDecodeWindowPos), count);
	

//	OutputDebugString("OK\n");
}


///////////// eof /////////////