/*
	flac.c

	FLAC support

	Copyright (C) 2005 Bill Currie <bill@taniwha.org>

	Author: Bill Currie <bill@taniwha.org>
	Date: 2005/6/15

	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; either version 2
	of the License, or (at your option) any later version.

	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 for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

static __attribute__ ((unused)) const char rcsid[] =
	"$Id$";

#ifdef HAVE_FLAC

#ifdef HAVE_STRING_H
# include "string.h"
#endif
#ifdef HAVE_STRINGS_H
# include "strings.h"
#endif

#include <stdlib.h>
#include <FLAC/seekable_stream_decoder.h>

#include "QF/cvar.h"
#include "QF/quakefs.h"
#include "QF/sound.h"
#include "QF/sys.h"

#include "snd_render.h"

typedef struct {
	FLAC__SeekableStreamDecoder *decoder;
	QFile      *file;
	FLAC__StreamMetadata_StreamInfo info;
	FLAC__StreamMetadata *vorbis_info;
	byte       *buffer;
	int         size;
	int         pos;
} flacfile_t;

static FLAC__SeekableStreamDecoderReadStatus
read_func (const FLAC__SeekableStreamDecoder *decoder, FLAC__byte buffer[],
		   unsigned *bytes, void *client_data)
{
	flacfile_t *ff = (flacfile_t *) client_data;
	*bytes = Qread (ff->file, buffer, *bytes);
	return FLAC__SEEKABLE_STREAM_DECODER_READ_STATUS_OK;
}

static FLAC__SeekableStreamDecoderSeekStatus
seek_func (const FLAC__SeekableStreamDecoder *decoder,
		   FLAC__uint64 absolute_byte_offset, void *client_data)
{
	flacfile_t *ff = (flacfile_t *) client_data;
	Qseek (ff->file, absolute_byte_offset, SEEK_SET);
	return FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_OK;
}

static FLAC__SeekableStreamDecoderTellStatus
tell_func (const FLAC__SeekableStreamDecoder *decoder,
		   FLAC__uint64 *absolute_byte_offset, void *client_data)
{
	flacfile_t *ff = (flacfile_t *) client_data;
	*absolute_byte_offset = Qtell (ff->file);
	return FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_OK;
}

static FLAC__SeekableStreamDecoderLengthStatus
length_func (const FLAC__SeekableStreamDecoder *decoder,
		   FLAC__uint64 *stream_length, void *client_data)
{
	flacfile_t *ff = (flacfile_t *) client_data;
	*stream_length = Qfilesize (ff->file);
	return FLAC__SEEKABLE_STREAM_DECODER_LENGTH_STATUS_OK;
}

static FLAC__bool
eof_func (const FLAC__SeekableStreamDecoder *decoder, void *client_data)
{
	flacfile_t *ff = (flacfile_t *) client_data;
	return Qeof (ff->file);
}

static FLAC__StreamDecoderWriteStatus
write_func (const FLAC__SeekableStreamDecoder *decoder,
			const FLAC__Frame *frame, const FLAC__int32 * const buffer[],
			void *client_data)
{
	flacfile_t *ff = (flacfile_t *) client_data;
	int         bps = ff->info.bits_per_sample / 8;
	if (ff->info.channels == 1) {
		memcpy (ff->buffer, buffer[0], bps * frame->header.blocksize);
	} else {
		unsigned    i;
		const FLAC__int32 *li = buffer[0];
		const FLAC__int32 *ri = buffer[1];

		if (ff->info.bits_per_sample == 8) {
			char       *lo = (char *) ff->buffer + 0;
			char       *ro = (char *) ff->buffer + 1;

			for (i = 0; i < frame->header.blocksize; i++, lo++, ro++) {
				*lo++ = *li++;
				*ro++ = *ri++;
			}
		} else {
			short      *lo = (short *) ff->buffer + 0;
			short      *ro = (short *) ff->buffer + 1;

			for (i = 0; i < frame->header.blocksize; i++, lo++, ro++) {
				*lo++ = *li++;
				*ro++ = *ri++;
			}
		}
	}
	ff->size = frame->header.blocksize;
	ff->pos = 0;
	return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
}

static void
meta_func (const FLAC__SeekableStreamDecoder *decoder,
		   const FLAC__StreamMetadata *metadata, void *client_data)
{
	flacfile_t *ff = (flacfile_t *) client_data;
	if (metadata->type == FLAC__METADATA_TYPE_STREAMINFO)
		ff->info = metadata->data.stream_info;
}

static flacfile_t *
open_flac (QFile *file)
{
	flacfile_t *ff = calloc (1, sizeof (flacfile_t));
	ff->decoder = FLAC__seekable_stream_decoder_new ();
	ff->file = file;

	FLAC__seekable_stream_decoder_set_read_callback (ff->decoder, read_func);
	FLAC__seekable_stream_decoder_set_seek_callback (ff->decoder, seek_func);
	FLAC__seekable_stream_decoder_set_tell_callback (ff->decoder, tell_func);
	FLAC__seekable_stream_decoder_set_length_callback (ff->decoder,
													   length_func);
	FLAC__seekable_stream_decoder_set_eof_callback (ff->decoder, eof_func);
	FLAC__seekable_stream_decoder_set_write_callback (ff->decoder, write_func);
	FLAC__seekable_stream_decoder_set_metadata_callback (ff->decoder,
														 meta_func);
	FLAC__seekable_stream_decoder_set_client_data (ff->decoder, ff);

	FLAC__seekable_stream_decoder_init (ff->decoder);
	FLAC__seekable_stream_decoder_process_until_end_of_metadata (ff->decoder);
	return ff;
}

static void
close_flac (flacfile_t *ff)
{
	FLAC__seekable_stream_decoder_finish (ff->decoder);
	FLAC__seekable_stream_decoder_delete (ff->decoder);

	Qclose (ff->file);

	free (ff);
}

static int
flac_read (flacfile_t *ff, byte *buf, int len)
{
	int         count = 0;

	while (len) {
		int         res = 0;
		if (ff->size == ff->pos)
			FLAC__seekable_stream_decoder_process_single (ff->decoder);
		res = ff->size - ff->pos;
		if (res > len)
			res = len;
		if (res > 0) {
			count += res;
			len -= res;
			buf += res;
		} else if (res < 0) {
			Sys_Printf ("flac error %d\n", res);
			return -1;
		} else {
			Sys_Printf ("unexpected eof\n");
			break;
		}
	}
	return count;
}

static sfxbuffer_t *
flac_load (flacfile_t *ff, sfxblock_t *block, cache_allocator_t allocator)
{
	byte       *data;
	sfxbuffer_t *sc = 0;
	sfx_t      *sfx = block->sfx;
	void       (*resample)(sfxbuffer_t *, byte *, int, void *);
	wavinfo_t  *info = &block->wavinfo;

	switch (ff->info.channels) {
		case 1:
			resample = SND_ResampleMono;
			break;
		case 2:
			resample = SND_ResampleStereo;
			break;
		default:
			Sys_Printf ("%s: unsupported channel count: %d\n",
						sfx->name, info->channels);
			return 0;
	}

	data = malloc (info->datalen);
	if (!data)
		goto bail;
	sc = SND_GetCache (info->samples, info->rate, info->width, info->channels,
					   block, allocator);
	if (!sc)
		goto bail;
	sc->sfx = sfx;
	if (flac_read (ff, data, info->datalen) < 0)
		goto bail;
	resample (sc, data, info->samples, 0);
	sc->head = sc->length;
  bail:
	if (data)
		free (data);
	close_flac (ff);
	return sc;
}

static void
flac_callback_load (void *object, cache_allocator_t allocator)
{
	QFile      *file;
	flacfile_t *ff;

	sfxblock_t *block = (sfxblock_t *) object;
	
	QFS_FOpenFile (block->file, &file);
	if (!file)
		return; //FIXME Sys_Error?

	if (!(ff = open_flac (file))) {
		Sys_Printf ("Input does not appear to be an Ogg bitstream.\n");
		Qclose (file);
		return; //FIXME Sys_Error?
	}
	flac_load (ff, block, allocator);
}

static void
flac_cache (sfx_t *sfx, char *realname, flacfile_t *ff, wavinfo_t info)
{
	sfxblock_t *block = calloc (1, sizeof (sfxblock_t));
	sfx->data = block;
	sfx->wavinfo = SND_CacheWavinfo;
	sfx->touch = SND_CacheTouch;
	sfx->retain = SND_CacheRetain;
	sfx->release = SND_CacheRelease;

	block->sfx = sfx;
	block->file = ff;
	block->wavinfo = info;

	Cache_Add (&block->cache, block, flac_callback_load);
}

static int
flac_stream_read (void *file, byte *buf, int count, wavinfo_t *info)
{
	return flac_read (file, buf, count);
}

static int
flac_stream_seek (void *file, int pos, wavinfo_t *info)
{
	return FLAC__seekable_stream_decoder_seek_absolute (file, pos);
}

static void
flac_stream_close (sfx_t *sfx)
{
	sfxstream_t *stream = (sfxstream_t *)sfx->data;

	close_flac (stream->file);
	free (stream);
	free (sfx);
}

static sfx_t *
flac_stream_open (sfx_t *_sfx)
{
	sfx_t      *sfx;
	sfxstream_t *stream = (sfxstream_t *) _sfx->data;
	wavinfo_t  *info = &stream->wavinfo;
	int         samples;
	int         size;
	QFile      *file;

	QFS_FOpenFile (stream->file, &file);
	if (!file)
		return 0;

	sfx = calloc (1, sizeof (sfx_t));
	samples = shm->speed * 0.3;
	size = samples = (samples + 255) & ~255;
	if (!snd_loadas8bit->int_val)
		size *= 2;
	if (info->channels == 2)
		size *= 2;
	stream = calloc (1, sizeof (sfxstream_t) + size);
	memcpy (stream->buffer.data + size, "\xde\xad\xbe\xef", 4);

	sfx->name = _sfx->name;
	sfx->data = stream;
	sfx->wavinfo = SND_CacheWavinfo;
	sfx->touch = sfx->retain = SND_StreamRetain;
	sfx->release = SND_StreamRelease;
	sfx->close = flac_stream_close;

	stream->sfx = sfx;
	stream->file = open_flac (file);
	if (!stream->file) {
		Sys_Printf ("Input does not appear to be a flac bitstream.\n");
		Qclose (file);
		free (stream);
		free (sfx);
		return 0;
	}
	stream->resample = info->channels == 2 ? SND_ResampleStereo
										  : SND_ResampleMono;
	stream->read = flac_stream_read;
	stream->seek = flac_stream_seek;
	stream->wavinfo = *info;

	stream->buffer.length = samples;
	stream->buffer.advance = SND_StreamAdvance;
	stream->buffer.setpos = SND_StreamSetPos;
	stream->buffer.sfx = sfx;

	stream->resample (&stream->buffer, 0, 0, 0);	// get sfx setup properly
	stream->seek (stream->file, 0, &stream->wavinfo);

	stream->buffer.advance (&stream->buffer, 0);

	return sfx;
}

static void
flac_stream (sfx_t *sfx, char *realname, flacfile_t *ff, wavinfo_t info)
{
	sfxstream_t *stream = calloc (1, sizeof (sfxstream_t));
		
	sfx->open = flac_stream_open;
	sfx->wavinfo = SND_CacheWavinfo;
	sfx->touch = sfx->retain = SND_StreamRetain;
	sfx->release = SND_StreamRelease;
	sfx->data = stream;

	stream->file = ff;
	stream->wavinfo = info;
}

static wavinfo_t
get_info (flacfile_t *ff)
{
	int         sample_start = -1, sample_count = 0;
	int         samples;
	wavinfo_t   info;
	FLAC__StreamMetadata_VorbisComment *vc;
	FLAC__StreamMetadata_VorbisComment_Entry *ve;
	FLAC__uint32 i;

	samples = ff->info.total_samples;
	vc = &ff->vorbis_info->data.vorbis_comment;

	for (i = 0, ve = vc->comments;
		 i < ff->vorbis_info->data.vorbis_comment.num_comments; ve++) {
		Sys_DPrintf ("%.*s\n", ve->length, ve->entry);
		if (strncmp ("CUEPOINT=", ve->entry, 9) == 0) {
			char       *str = alloca (ve->length + 1);
			strncpy (str, ve->entry, ve->length);
			str[ve->length] = 0;
			sscanf (str + 9, "%d %d", &sample_start, &sample_count);
		}
	}

	if (sample_start != -1)
		samples = sample_start + sample_count;

	info.rate = ff->info.sample_rate;
	info.width = ff->info.bits_per_sample / 8;
	info.channels = ff->info.channels;
	info.loopstart = sample_start;
	info.samples = samples;
	info.dataofs = 0;
	info.datalen = samples * 2;

	if (developer->int_val) {
		Sys_Printf ("\nBitstream is %d channel, %dHz\n",
					info.channels, info.rate);
		Sys_Printf ("\nDecoded length: %d samples (%d bytes)\n",
					info.samples, info.samples * info.channels * 2);
		Sys_Printf ("Encoded by: %.*s\n\n",
					vc->vendor_string.length, vc->vendor_string.entry);
	}

	return info;
}

void
SND_LoadFLAC (QFile *file, sfx_t *sfx, char *realname)
{
	flacfile_t *ff;
	wavinfo_t   info;

	if (!(ff = open_flac (file))) {
		Sys_Printf ("Input does not appear to be an Ogg bitstream.\n");
		Qclose (file);
		return;
	}
	info = get_info (ff);
	if (info.channels < 1 || info.channels > 2) {
		Sys_Printf ("unsupported number of channels");
		return;
	}
	if (info.samples / info.rate < 3) {
		Sys_DPrintf ("cache %s\n", realname);
		flac_cache (sfx, realname, ff, info);
	} else {
		Sys_DPrintf ("stream %s\n", realname);
		flac_stream (sfx, realname, ff, info);
	}
}

#endif//HAVE_FLAC