///
///	@file codec.c	@brief Codec functions
///
///	Copyright (c) 2009 - 2011 by Johns.  All Rights Reserved.
///
///	Contributor(s):
///
///	License: AGPLv3
///
///	This program is free software: you can redistribute it and/or modify
///	it under the terms of the GNU Affero General Public License as
///	published by the Free Software Foundation, either version 3 of the
///	License.
///
///	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 Affero General Public License for more details.
///
///	$Id$
//////////////////////////////////////////////////////////////////////////////

///
///	@defgroup Codec The codec module.
///
///		This module contains all decoder and codec functions.
///		It is uses ffmpeg (http://ffmpeg.org) as backend.
///

#include <stdio.h>
#include <unistd.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <libintl.h>
#define _(str) gettext(str)		///< gettext shortcut
#define _N(str) str			///< gettext_noop shortcut

#include <alsa/iatomic.h>
#include <libavcodec/avcodec.h>
#include <libavcodec/vaapi.h>

#ifdef MAIN_H
#include MAIN_H
#endif
#include "misc.h"
#include "video.h"
#include "audio.h"
#include "codec.h"

//----------------------------------------------------------------------------
//	Video
//----------------------------------------------------------------------------

#if 0
///
///	Video decoder typedef.
///
//typedef struct _video_decoder_ Decoder;
#endif

///
///	Video decoder structure.
///
struct _video_decoder_
{
    VideoHwDecoder *HwDecoder;		///< video hardware decoder

    AVCodec *VideoCodec;		///< video codec
    AVCodecContext *VideoCtx;		///< video codec context
    AVFrame *Frame;			///< decoded video frame
};

//----------------------------------------------------------------------------
//	Call-backs
//----------------------------------------------------------------------------

static int CodecFfmpegOk;		///< check ffmpeg idiotics

/**
**	Callback to negotiate the PixelFormat.
**
**	@param fmt	is the list of formats which are supported by the codec,
**			it is terminated by -1 as 0 is a valid format, the
**			formats are ordered by quality.
*/
static enum PixelFormat Codec_get_format(AVCodecContext * video_ctx,
    const enum PixelFormat *fmt)
{
    VideoDecoder *decoder;

    decoder = video_ctx->opaque;
    Debug(3, "codec: %s: %18p\n", __FUNCTION__, decoder);
    CodecFfmpegOk = 1;
    return Video_get_format(decoder->HwDecoder, video_ctx, fmt);
}

/**
**	Video buffer management, get buffer for frame.
**
**	Called at the beginning of each frame to get a buffer for it.
**
**	@param video_ctx	Codec context
**	@param frame		Get buffer for this frame
*/
static int Codec_get_buffer(AVCodecContext * video_ctx, AVFrame * frame)
{
    if (!CodecFfmpegOk) {		// get_format missing
	enum PixelFormat fmts[2];

	fprintf(stderr, "codec: buggy ffmpeg\n");
	fmts[0] = video_ctx->pix_fmt;
	fmts[1] = PIX_FMT_NONE;
	Codec_get_format(video_ctx, fmts);
    }
    // VDPAU: PIX_FMT_VDPAU_H264 .. PIX_FMT_VDPAU_VC1 PIX_FMT_VDPAU_MPEG4
    if ((PIX_FMT_VDPAU_H264 <= video_ctx->pix_fmt
	    && video_ctx->pix_fmt <= PIX_FMT_VDPAU_VC1)
	|| video_ctx->pix_fmt == PIX_FMT_VDPAU_MPEG4) {
	VideoDecoder *decoder;
	unsigned surface;

	decoder = video_ctx->opaque;
	surface = VideoGetSurface(decoder->HwDecoder);

	//Debug(3, "codec: use surface %#010x\n", surface);

	frame->type = FF_BUFFER_TYPE_USER;
	frame->age = 256 * 256 * 256 * 64;
	frame->data[0] = (void *)(size_t) surface;

	// FIXME: reordered?
	return 0;
    }
    // VA-API:
    if (video_ctx->hwaccel_context) {
	VideoDecoder *decoder;
	unsigned surface;

	decoder = video_ctx->opaque;
	surface = VideoGetSurface(decoder->HwDecoder);

	//Debug(3, "codec: use surface %#010x\n", surface);

	frame->type = FF_BUFFER_TYPE_USER;
	frame->age = 256 * 256 * 256 * 64;
	// vaapi needs both fields set
	frame->data[0] = (void *)(size_t) surface;
	frame->data[3] = (void *)(size_t) surface;

	// FIXME: reordered?
	return 0;
    }
    //Debug(3, "codec: fallback to default get_buffer\n");
    return avcodec_default_get_buffer(video_ctx, frame);
}

/**
**	Video buffer management, release buffer for frame.
**	Called to release buffers which were allocated with get_buffer.
**
**	@param video_ctx	Codec context
**	@param frame		Release buffer for this frame
*/
static void Codec_release_buffer(AVCodecContext * video_ctx, AVFrame * frame)
{
    // VDPAU: PIX_FMT_VDPAU_H264 .. PIX_FMT_VDPAU_VC1 PIX_FMT_VDPAU_MPEG4
    if ((PIX_FMT_VDPAU_H264 <= video_ctx->pix_fmt
	    && video_ctx->pix_fmt <= PIX_FMT_VDPAU_VC1)
	|| video_ctx->pix_fmt == PIX_FMT_VDPAU_MPEG4) {
	VideoDecoder *decoder;
	unsigned surface;

	decoder = video_ctx->opaque;
	surface = (unsigned)(size_t) frame->data[0];

	//Debug(3, "codec: release surface %#010x\n", surface);
	VideoReleaseSurface(decoder->HwDecoder, surface);

	frame->data[0] = NULL;

	return;
    }
    // VA-API
    if (video_ctx->hwaccel_context) {
	VideoDecoder *decoder;
	unsigned surface;

	decoder = video_ctx->opaque;
	surface = (unsigned)(size_t) frame->data[3];

	//Debug(3, "codec: release surface %#010x\n", surface);
	VideoReleaseSurface(decoder->HwDecoder, surface);

	frame->data[0] = NULL;
	frame->data[3] = NULL;

	return;
    }
    //Debug(3, "codec: fallback to default release_buffer\n");
    return avcodec_default_release_buffer(video_ctx, frame);
}

//----------------------------------------------------------------------------
//	Test
//----------------------------------------------------------------------------

/**
**	Allocate a new video decoder context.
**
**	@param hw_decoder	video hardware decoder
**
**	@returns private decoder pointer for audio/video decoder.
*/
VideoDecoder *CodecVideoNewDecoder(VideoHwDecoder * hw_decoder)
{
    VideoDecoder *decoder;

    if (!(decoder = calloc(1, sizeof(*decoder)))) {
	Fatal(_("codec: Can't allocate vodeo decoder\n"));
    }
    decoder->HwDecoder = hw_decoder;

    return decoder;
}

/**
**	Open video decoder.
**
**	@param decoder	private video decoder
**	@param name	video codec name
**	@param codec_id	video codec id, used if name == NULL
*/
void CodecVideoOpen(VideoDecoder * decoder, const char *name, int codec_id)
{
    AVCodec *video_codec;

    Debug(3, "codec: using codec %s or ID %#04x\n", name, codec_id);

    //
    //	ffmpeg compatibility hack
    //
#if LIBAVCODEC_VERSION_INT <= AV_VERSION_INT(52,96,0)
    if (name) {
	if (!strcmp(name, "h264video_vdpau")) {
	    name = "h264_vdpau";
	} else if (!strcmp(name, "mpeg4video_vdpau")) {
	    name = "mpeg4_vdpau";
	} else if (!strcmp(name, "vc1video_vdpau")) {
	    name = "vc1_vdpau";
	} else if (!strcmp(name, "wmv3video_vdpau")) {
	    name = "wmv3_vdpau";
	}
    }
#endif

    if (name && (video_codec = avcodec_find_decoder_by_name(name))) {
	Debug(3, "codec: vdpau decoder found\n");
    } else if (!(video_codec = avcodec_find_decoder(codec_id))) {
	Fatal(_("codec: codec ID %#04x not found\n"), codec_id);
    }
    decoder->VideoCodec = video_codec;

    if (!(decoder->VideoCtx = avcodec_alloc_context3(video_codec))) {
	Fatal(_("codec: can't allocate video codec context\n"));
    }
    // open codec
    if (avcodec_open2(decoder->VideoCtx, video_codec, NULL) < 0) {
	Fatal(_("codec: can't open video codec!\n"));
    }

    decoder->VideoCtx->opaque = decoder;	// our structure

    /*
       // FIXME: the number of cpu's should be configurable
       // Today this makes no big sense H264 is broken with current streams.
       avcodec_thread_init(decoder->VideoCtx, 2);	// support dual-cpu's
     */

    Debug(3, "codec: video '%s'\n", decoder->VideoCtx->codec_name);
    if (codec_id == CODEC_ID_H264) {
	// 2.53 Ghz CPU is too slow for this codec at 1080i
	//decoder->VideoCtx->skip_loop_filter = AVDISCARD_ALL;
	//decoder->VideoCtx->skip_loop_filter = AVDISCARD_BIDIR;
    }
    if (video_codec->capabilities & CODEC_CAP_TRUNCATED) {
	Debug(3, "codec: video can use truncated packets\n");
	// we do not send complete frames
	decoder->VideoCtx->flags |= CODEC_FLAG_TRUNCATED;
    }
    // FIXME: own memory management for video frames.
    if (video_codec->capabilities & CODEC_CAP_DR1) {
	Debug(3, "codec: can use own buffer management\n");
    }
    if (video_codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
	Debug(3, "codec: can export data for HW decoding (VDPAU)\n");
    }
#ifdef CODEC_CAP_FRAME_THREADS
    if (video_codec->capabilities & CODEC_CAP_FRAME_THREADS) {
	Debug(3, "codec: codec supports frame threads\n");
    }
#endif
    //decoder->VideoCtx->debug = FF_DEBUG_STARTCODE;

    if (video_codec->capabilities & CODEC_CAP_HWACCEL_VDPAU) {
	// FIXME: get_format never called.
	decoder->VideoCtx->get_format = Codec_get_format;
	decoder->VideoCtx->get_buffer = Codec_get_buffer;
	decoder->VideoCtx->release_buffer = Codec_release_buffer;
	decoder->VideoCtx->reget_buffer = Codec_get_buffer;
	//decoder->VideoCtx->draw_horiz_band = Codec_draw_horiz_band;
    } else {
	decoder->VideoCtx->hwaccel_context =
	    VideoGetVaapiContext(decoder->HwDecoder);
    }

    // our pixel format video hardware decoder hook
    if (decoder->VideoCtx->hwaccel_context) {
	decoder->VideoCtx->get_format = Codec_get_format;
	decoder->VideoCtx->get_buffer = Codec_get_buffer;
	decoder->VideoCtx->release_buffer = Codec_release_buffer;
	decoder->VideoCtx->reget_buffer = Codec_get_buffer;
#if 0
	decoder->VideoCtx->thread_count = 1;
	decoder->VideoCtx->draw_horiz_band = NULL;
	decoder->VideoCtx->slice_flags =
	    SLICE_FLAG_CODED_ORDER | SLICE_FLAG_ALLOW_FIELD;
	//decoder->VideoCtx->flags |= CODEC_FLAG_EMU_EDGE;
#endif
    }
    //
    //	Prepare frame buffer for decoder
    //
    if (!(decoder->Frame = avcodec_alloc_frame())) {
	Fatal(_("codec: can't allocate decoder frame\n"));
    }
}

/**
**	Close video decoder.
**
**	@param video_decoder	private video decoder
*/
void CodecVideoClose(VideoDecoder * video_decoder)
{
    (void)video_decoder;
    // FIXME: write close code
}

#if 0

#ifdef DEBUG

/**
**	Display pts...
*/
void DisplayPts(AVCodecContext * video_ctx, AVFrame * frame)
{
    int ms_delay;

    if (frame->pts == (int64_t) AV_NOPTS_VALUE) {
	printf("*");
    }
    ms_delay = (1000 * video_ctx->time_base.num) / video_ctx->time_base.den;
    ms_delay += frame->repeat_pict * ms_delay / 2;
    printf("codec: PTS %s%s %" PRId64 " %d/%d %dms\n",
	frame->repeat_pict ? "r" : " ", frame->interlaced_frame ? "I" : " ",
	frame->pts, video_ctx->time_base.num, video_ctx->time_base.den,
	ms_delay);
}
#endif

#endif

/**
**	Decode a video packet.
**
**	@param decoder	video decoder data
**	@param avpkt	video packet
**
**	@note this version destroys avpkt!!
*/
void CodecVideoDecode(VideoDecoder * decoder, AVPacket * avpkt)
{
    AVCodecContext *video_ctx;
    AVFrame *frame;
    int used;
    int got_frame;

    video_ctx = decoder->VideoCtx;
    frame = decoder->Frame;

  next_part:
    // FIXME: this function can crash with bad packets
    used = avcodec_decode_video2(video_ctx, frame, &got_frame, avpkt);
    Debug(4, "%s: %p %d -> %d %d\n", __FUNCTION__, avpkt->data, avpkt->size,
	used, got_frame);

    if (got_frame) {			// frame completed
	//DisplayPts(video_ctx, frame);
	if (video_ctx->hwaccel_context) {
	    VideoRenderFrame(decoder->HwDecoder, video_ctx, frame);
	} else {
	    VideoRenderFrame(decoder->HwDecoder, video_ctx, frame);
	}
    } else {
	// some frames are needed for references, interlaced frames ...
	// could happen with h264 dvb streams, just drop data.

	Debug(4, "codec: %8d incomplete interlaced frame %d bytes used\n",
	    video_ctx->frame_number, used);
    }
    if (used != avpkt->size) {
	if (used == 0) {
	    goto next_part;
	}
	if (used >= 0) {
	    // some tv channels, produce this
	    Debug(4,
		"codec: ooops didn't use complete video packet used %d of %d\n",
		used, avpkt->size);
	    avpkt->data += used;
	    avpkt->size -= used;
	    goto next_part;
	}
	Debug(3, "codec: bad frame %d\n", used);
    }

    return;
}

//----------------------------------------------------------------------------
//	Audio
//----------------------------------------------------------------------------

#if 0
///
///	Audio decoder typedef.
///
typedef struct _audio_decoder_ AudioDecoder;
#endif

///
///	Audio decoder structure.
///
struct _audio_decoder_
{
    AVCodec *AudioCodec;		///< audio codec
    AVCodecContext *AudioCtx;		///< audio codec context

    /// audio parser to support wired dvb streaks
    AVCodecParserContext *AudioParser;
    int SampleRate;			///< old sample rate
    int Channels;			///< old channels
};

/**
**	Allocate a new audio decoder context.
**
**	@param hw_decoder	video hardware decoder
**
**	@returns private decoder pointer for audio/video decoder.
*/
AudioDecoder *CodecAudioNewDecoder(void)
{
    AudioDecoder *audio_decoder;

    if (!(audio_decoder = calloc(1, sizeof(*audio_decoder)))) {
	Fatal(_("codec: Can't allocate audio decoder\n"));
    }

    return audio_decoder;
}

/**
**	Open audio decoder.
**
**	@param audio_decoder	private audio decoder
**	@param name	audio codec name
**	@param codec_id	audio codec id, used if name == NULL
*/
void CodecAudioOpen(AudioDecoder * audio_decoder, const char *name,
    int codec_id)
{
    AVCodec *audio_codec;

    if (name && (audio_codec = avcodec_find_decoder_by_name(name))) {
	Debug(3, "codec: audio decoder '%s' found\n", name);
    } else if (!(audio_codec = avcodec_find_decoder(codec_id))) {
	Fatal(_("codec: codec ID %#04x not found\n"), codec_id);
	// FIXME: errors aren't fatal
    }
    audio_decoder->AudioCodec = audio_codec;

    if (!(audio_decoder->AudioCtx = avcodec_alloc_context3(audio_codec))) {
	Fatal(_("codec: can't allocate audio codec context\n"));
    }
    // open codec
    if (avcodec_open2(audio_decoder->AudioCtx, audio_codec, NULL) < 0) {
	Fatal(_("codec: can't open audio codec\n"));
    }
    Debug(3, "codec: audio '%s'\n", audio_decoder->AudioCtx->codec_name);

    if (audio_codec->capabilities & CODEC_CAP_TRUNCATED) {
	Debug(3, "codec: audio can use truncated packets\n");
	// we do not send complete frames
	audio_decoder->AudioCtx->flags |= CODEC_FLAG_TRUNCATED;
    }
    if (!(audio_decoder->AudioParser =
	    av_parser_init(audio_decoder->AudioCtx->codec_id))) {
	Fatal(_("codec: can't init audio parser\n"));
    }
}

/**
**	Close audio decoder.
**
**	@param audio_decoder	private audio decoder
*/
void CodecAudioClose(AudioDecoder * audio_decoder)
{
    // FIXME: output any buffered data
    if (audio_decoder->AudioParser) {
	av_parser_close(audio_decoder->AudioParser);
	audio_decoder->AudioParser = NULL;
    }
    if (audio_decoder->AudioCtx) {
	avcodec_close(audio_decoder->AudioCtx);
	av_freep(&audio_decoder->AudioCtx);
    }
}

/**
**	Decode an audio packet.
**
**	PTS must be handled self.
**
**	@param audio_decoder	audio_Decoder data
**	@param avpkt		audio packet
*/
void CodecAudioDecode(AudioDecoder * audio_decoder, AVPacket * avpkt)
{
    int16_t buf[(AVCODEC_MAX_AUDIO_FRAME_SIZE * 3) / 4 +
	FF_INPUT_BUFFER_PADDING_SIZE] __attribute__ ((aligned(16)));
    AVCodecContext *audio_ctx;
    int index;
    AVPacket spkt[1];

    if (!audio_decoder->AudioParser) {
	Fatal(_("codec: internal error parser freeded while running\n"));
    }

    if (av_new_packet(spkt, avpkt->size + FF_INPUT_BUFFER_PADDING_SIZE)) {
	Error(_("codec: out of memory\n"));
	return;
    }
    memcpy(spkt->data, avpkt->data, avpkt->size);
    memset(spkt->data + avpkt->size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
    audio_ctx = audio_decoder->AudioCtx;
    index = 0;
    while (avpkt->size > index) {
	int n;
	int l;
	AVPacket dpkt[1];

	av_init_packet(dpkt);
	n = av_parser_parse2(audio_decoder->AudioParser, audio_ctx,
	    &dpkt->data, &dpkt->size, spkt->data + index, avpkt->size - index,
	    AV_NOPTS_VALUE, AV_NOPTS_VALUE, AV_NOPTS_VALUE);

	if (dpkt->size) {
	    int buf_sz;

	    buf_sz = sizeof(buf);
	    l = avcodec_decode_audio3(audio_ctx, buf, &buf_sz, dpkt);
	    if (l < 0) {		// no audio frame could be decompressed
		Error(_("codec: error audio data\n"));
		break;
	    }
#ifdef notyetFF_API_OLD_DECODE_AUDIO
	    // FIXME: ffmpeg git comeing
	    int got_frame;

	    avcodec_decode_audio4(audio_ctx, frame, &got_frame, dpkt);
#else
#endif
	    // FIXME: must first play remainings bytes, than change and play new.
	    if (audio_decoder->SampleRate != audio_ctx->sample_rate
		|| audio_decoder->Channels != audio_ctx->channels) {

		// FIXME: channels not support?
		AudioSetup(audio_ctx->sample_rate, audio_ctx->channels);

		audio_decoder->SampleRate = audio_ctx->sample_rate;
		audio_decoder->Channels = audio_ctx->channels;
	    }
	    AudioEnqueue(buf, buf_sz);

	    if (dpkt->size > l) {
		Error(_("codec: error more than one frame data\n"));
	    }
	}

	index += n;
    }
    av_destruct_packet(spkt);
}

//----------------------------------------------------------------------------
//	Codec
//----------------------------------------------------------------------------

/**
**	Codec init
*/
void CodecInit(void)
{
    avcodec_register_all();		// register all formats and codecs
}

/**
**	Codec exit.
*/
void CodecExit(void)
{
}