/*
	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

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

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

#include "qfalloca.h"

/* FLAC 1.1.3 has FLAC_API_VERSION_CURRENT == 8 */
#if !defined(FLAC_API_VERSION_CURRENT) || FLAC_API_VERSION_CURRENT < 8
#define LEGACY_FLAC
#else
#undef LEGACY_FLAC
#endif

#ifdef LEGACY_FLAC
#include <FLAC/seekable_stream_decoder.h>
#else
#include <FLAC/stream_decoder.h>
#endif
#include <FLAC/metadata.h>

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

#include "snd_internal.h"

#ifdef LEGACY_FLAC
#define FLAC__StreamDecoder FLAC__SeekableStreamDecoder
#define FLAC__StreamDecoderReadStatus FLAC__SeekableStreamDecoderReadStatus
#define FLAC__StreamDecoderSeekStatus FLAC__SeekableStreamDecoderSeekStatus
#define FLAC__StreamDecoderTellStatus FLAC__SeekableStreamDecoderTellStatus
#define FLAC__StreamDecoderLengthStatus FLAC__SeekableStreamDecoderLengthStatus

#define FLAC__stream_decoder_new FLAC__seekable_stream_decoder_new
#define FLAC__stream_decoder_finish FLAC__seekable_stream_decoder_finish
#define FLAC__stream_decoder_delete FLAC__seekable_stream_decoder_delete
#define FLAC__stream_decoder_process_single \
		FLAC__seekable_stream_decoder_process_single
#define FLAC__stream_decoder_seek_absolute \
		FLAC__seekable_stream_decoder_seek_absolute

#define FLAC__STREAM_DECODER_READ_STATUS_CONTINUE \
		FLAC__SEEKABLE_STREAM_DECODER_READ_STATUS_OK
#define FLAC__STREAM_DECODER_SEEK_STATUS_OK \
		FLAC__SEEKABLE_STREAM_DECODER_SEEK_STATUS_OK
#define FLAC__STREAM_DECODER_TELL_STATUS_OK \
		FLAC__SEEKABLE_STREAM_DECODER_TELL_STATUS_OK
#define FLAC__STREAM_DECODER_LENGTH_STATUS_OK \
		FLAC__SEEKABLE_STREAM_DECODER_LENGTH_STATUS_OK
#endif

typedef struct {
	FLAC__StreamDecoder *decoder;
	QFile      *file;
	FLAC__StreamMetadata_StreamInfo info;
	FLAC__StreamMetadata *vorbis_info;
	float      *buffer;
	int         size;					// in frames
	int         pos;					// in frames
} flacfile_t;

static void
flac_error_func (const FLAC__StreamDecoder *decoder,
				 FLAC__StreamDecoderErrorStatus status, void *client_data)
{
}

static FLAC__StreamDecoderReadStatus
flac_read_func (const FLAC__StreamDecoder *decoder, FLAC__byte buffer[],
			    size_t *bytes, void *client_data)
{
	flacfile_t *ff = (flacfile_t *) client_data;
	*bytes = Qread (ff->file, buffer, *bytes);
	return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
}

static FLAC__StreamDecoderSeekStatus
flac_seek_func (const FLAC__StreamDecoder *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__STREAM_DECODER_SEEK_STATUS_OK;
}

static FLAC__StreamDecoderTellStatus
flac_tell_func (const FLAC__StreamDecoder *decoder,
			    FLAC__uint64 *absolute_byte_offset, void *client_data)
{
	flacfile_t *ff = (flacfile_t *) client_data;
	*absolute_byte_offset = Qtell (ff->file);
	return FLAC__STREAM_DECODER_TELL_STATUS_OK;
}

static FLAC__StreamDecoderLengthStatus
flac_length_func (const FLAC__StreamDecoder *decoder,
				  FLAC__uint64 *stream_length, void *client_data)
{
	flacfile_t *ff = (flacfile_t *) client_data;
	*stream_length = Qfilesize (ff->file);
	return FLAC__STREAM_DECODER_LENGTH_STATUS_OK;
}

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

static FLAC__StreamDecoderWriteStatus
flac_write_func (const FLAC__StreamDecoder *decoder,
				 const FLAC__Frame *frame, const FLAC__int32 * const buffer[],
				 void *client_data)
{
	flacfile_t *ff = (flacfile_t *) client_data;
	float      *out;
	float       scale = 2.0 / (1 << ff->info.bits_per_sample);
	int         step = ff->info.channels;
	unsigned    j;
	int         i;

	if (!ff->buffer)
		ff->buffer = calloc (ff->info.max_blocksize * ff->info.channels,
							 sizeof (float));
	ff->size = frame->header.blocksize;
	ff->pos = 0;
	for (j = 0; j < ff->info.channels; j++) {
		const FLAC__int32 *in = buffer[j];

		out = ff->buffer + j;
		for (i = 0; i < ff->size; i++, out += step)
			*out = *in++ * scale;
	}
	return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
}

static void
flac_meta_func (const FLAC__StreamDecoder *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;
	if (metadata->type == FLAC__METADATA_TYPE_VORBIS_COMMENT)
		ff->vorbis_info = FLAC__metadata_object_clone (metadata);
}

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

#ifdef LEGACY_FLAC
	FLAC__seekable_stream_decoder_set_error_callback (ff->decoder,
													  flac_error_func);
	FLAC__seekable_stream_decoder_set_read_callback (ff->decoder,
													 flac_read_func);
	FLAC__seekable_stream_decoder_set_seek_callback (ff->decoder,
													 flac_seek_func);
	FLAC__seekable_stream_decoder_set_tell_callback (ff->decoder,
													 flac_tell_func);
	FLAC__seekable_stream_decoder_set_length_callback (ff->decoder,
													   flac_length_func);
	FLAC__seekable_stream_decoder_set_eof_callback (ff->decoder,
													flac_eof_func);
	FLAC__seekable_stream_decoder_set_write_callback (ff->decoder,
													  flac_write_func);
	FLAC__seekable_stream_decoder_set_metadata_callback (ff->decoder,
														 flac_meta_func);
	FLAC__seekable_stream_decoder_set_client_data (ff->decoder, ff);
	FLAC__seekable_stream_decoder_set_metadata_respond (ff->decoder,
			FLAC__METADATA_TYPE_VORBIS_COMMENT);

	FLAC__seekable_stream_decoder_init (ff->decoder);
	FLAC__seekable_stream_decoder_process_until_end_of_metadata (ff->decoder);
#else
	FLAC__stream_decoder_set_metadata_respond (ff->decoder,
			FLAC__METADATA_TYPE_VORBIS_COMMENT);
	FLAC__stream_decoder_init_stream(ff->decoder,
									 flac_read_func, flac_seek_func,
									 flac_tell_func, flac_length_func,
									 flac_eof_func, flac_write_func,
									 flac_meta_func, flac_error_func,
									 ff);
	FLAC__stream_decoder_process_until_end_of_metadata (ff->decoder);
#endif
	return ff;
}

static void
flac_close (flacfile_t *ff)
{
	FLAC__stream_decoder_finish (ff->decoder);
	FLAC__stream_decoder_delete (ff->decoder);

	if (ff->vorbis_info)
		FLAC__metadata_object_delete (ff->vorbis_info);

	if (ff->buffer)
		free (ff->buffer);

	Qclose (ff->file);

	free (ff);
}

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

	while (len) {
		int         res = 0;
		if (ff->size == ff->pos)
			FLAC__stream_decoder_process_single (ff->decoder);
		res = ff->size - ff->pos;
		if (res > len)
			res = len;
		if (res > 0) {
			memcpy (buf, ff->buffer + ff->pos * ff->info.channels,
					res * ff->info.channels * sizeof (float));
			count += res;
			len -= res;
			buf += res * ff->info.channels;
			ff->pos += 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)
{
	float      *data;
	sfxbuffer_t *sc = 0;
	sfx_t      *sfx = block->sfx;
	wavinfo_t  *info = &block->wavinfo;

	data = malloc (info->datalen);
	if (!data)
		goto bail;
	sc = SND_GetCache (info->frames, info->rate, info->channels,
					   block, allocator);
	if (!sc)
		goto bail;
	sc->sfx = sfx;
	if (flac_read (ff, data, info->frames) < 0)
		goto bail;
	SND_SetPaint (sc);
	SND_SetupResampler (sc, 0);
	SND_Resample (sc, data, info->frames);
	sc->head = sc->length;
  bail:
	if (data)
		free (data);
	flac_close (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;

	file = QFS_FOpenFile (block->file);
	if (!file)
		return; //FIXME Sys_Error?

	if (!(ff = flac_open (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)
{
	flac_close (ff);
	SND_SFX_Cache (sfx, realname, info, flac_callback_load);
}

static long
flac_stream_read (void *file, float **buf)
{
	sfxstream_t *stream = (sfxstream_t *) file;
	flacfile_t *ff = (flacfile_t *) stream->file;
	int res = FLAC__stream_decoder_process_single (ff->decoder);

	if (!res) {
		stream->error = 1;
		return 0;
	}
	*buf = ff->buffer;
	return ff->size;
}

static int
flac_stream_seek (sfxstream_t *stream, int pos)
{
	flacfile_t *ff = stream->file;

	ff->pos = ff->size = 0;
	return FLAC__stream_decoder_seek_absolute (ff->decoder, pos);
}

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

	flac_close (stream->file);
	SND_SFX_StreamClose (sfx);
}

static sfx_t *
flac_stream_open (sfx_t *sfx)
{
	sfxstream_t *stream = sfx->data.stream;
	QFile      *file;
	void       *f;

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

	f = flac_open (file);
	if (!f) {
		Sys_Printf ("Input does not appear to be a flac bitstream.\n");
		Qclose (file);
		return 0;
	}

	return SND_SFX_StreamOpen (sfx, f, flac_stream_read, flac_stream_seek,
							   flac_stream_close);
}

static void
flac_stream (sfx_t *sfx, char *realname, flacfile_t *ff, wavinfo_t info)
{
	flac_close (ff);
	SND_SFX_Stream (sfx, realname, info, flac_stream_open);
}

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

	samples = ff->info.total_samples;
	if (ff->vorbis_info) {
		vc = &ff->vorbis_info->data.vorbis_comment;

		for (i = 0, ve = vc->comments; i < vc->num_comments; ve++, i++) {
			Sys_MaskPrintf (SYS_DEV, "%.*s\n", ve->length, ve->entry);
			if (strncmp ("CUEPOINT=", (char *) ve->entry, 9) == 0) {
				char       *str = alloca (ve->length + 1);
				strncpy (str, (char *) 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.frames = samples;
	info.dataofs = 0;
	info.datalen = samples * info.channels * sizeof (float);

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

	return info;
}

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

	if (!(ff = flac_open (file))) {
		Sys_Printf ("Input does not appear to be a FLAC bitstream.\n");
		return -1;
	}
	info = flac_get_info (ff);
	if (info.channels < 1 || info.channels > 8) {
		Sys_Printf ("unsupported number of channels");
		return -1;
	}
	if (info.frames / info.rate < 3) {
		Sys_MaskPrintf (SYS_DEV, "cache %s\n", realname);
		flac_cache (sfx, realname, ff, info);
	} else {
		Sys_MaskPrintf (SYS_DEV, "stream %s\n", realname);
		flac_stream (sfx, realname, ff, info);
	}
	return 0;
}
