/*
  * RIFF muxing functions
  * Copyright (c) 2000 Fabrice Bellard
  *

  * This file is part of FFmpeg.

  *

  * FFmpeg is free software; you can redistribute it and/or

  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *

  * FFmpeg 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
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public

  * License along with FFmpeg; if not, write to the Free Software

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include "libavutil/dict.h"
 #include "libavutil/log.h"
 #include "libavutil/mathematics.h"
 #include "libavcodec/avcodec.h"
 #include "libavcodec/bytestream.h"
 #include "avformat.h"
 #include "avio_internal.h"
 #include "riff.h"
 
 int64_t ff_start_tag(AVIOContext *pb, const char *tag)
 {
     ffio_wfourcc(pb, tag);

     avio_wl32(pb, -1);

     return avio_tell(pb);
 }
 
 void ff_end_tag(AVIOContext *pb, int64_t start)
 {
     int64_t pos;
 

     av_assert0((start&1) == 0);
 

     pos = avio_tell(pb);

     if (pos & 1)
         avio_w8(pb, 0);

     avio_seek(pb, start - 4, SEEK_SET);
     avio_wl32(pb, (uint32_t)(pos - start));

     avio_seek(pb, FFALIGN(pos, 2), SEEK_SET);

 }
 
 /* WAVEFORMATEX header */
 /* returns the size or -1 on error */

 int ff_put_wav_header(AVIOContext *pb, AVCodecContext *enc, int flags)

 {
     int bps, blkalign, bytespersec, frame_size;

     int hdrsize;
     int64_t hdrstart = avio_tell(pb);

     int waveformatextensible;
     uint8_t temp[256];
     uint8_t *riff_extradata       = temp;
     uint8_t *riff_extradata_start = temp;
 
     if (!enc->codec_tag || enc->codec_tag > 0xffff)
         return -1;
 
     /* We use the known constant frame size for the codec if known, otherwise
      * fall back on using AVCodecContext.frame_size, which is not as reliable
      * for indicating packet duration. */

     frame_size = av_get_audio_frame_duration(enc, enc->block_align);

 
     waveformatextensible = (enc->channels > 2 && enc->channel_layout) ||
                            enc->sample_rate > 48000 ||

                            enc->codec_id == AV_CODEC_ID_EAC3 ||

                            av_get_bits_per_sample(enc->codec_id) > 16;
 
     if (waveformatextensible)
         avio_wl16(pb, 0xfffe);
     else
         avio_wl16(pb, enc->codec_tag);
 
     avio_wl16(pb, enc->channels);
     avio_wl32(pb, enc->sample_rate);

     if (enc->codec_id == AV_CODEC_ID_ATRAC3 ||
         enc->codec_id == AV_CODEC_ID_G723_1 ||
         enc->codec_id == AV_CODEC_ID_MP2    ||
         enc->codec_id == AV_CODEC_ID_MP3    ||

         enc->codec_id == AV_CODEC_ID_GSM_MS) {
         bps = 0;
     } else {
         if (!(bps = av_get_bits_per_sample(enc->codec_id))) {
             if (enc->bits_per_coded_sample)
                 bps = enc->bits_per_coded_sample;
             else
                 bps = 16;  // default to 16
         }
     }
     if (bps != enc->bits_per_coded_sample && enc->bits_per_coded_sample) {
         av_log(enc, AV_LOG_WARNING,
                "requested bits_per_coded_sample (%d) "
                "and actually stored (%d) differ\n",
                enc->bits_per_coded_sample, bps);
     }
 

     if (enc->codec_id == AV_CODEC_ID_MP2) {

         blkalign = frame_size;

     } else if (enc->codec_id == AV_CODEC_ID_MP3) {

         blkalign = 576 * (enc->sample_rate <= (24000 + 32000)/2 ? 1 : 2);

     } else if (enc->codec_id == AV_CODEC_ID_AC3) {
         blkalign = 3840;                /* maximum bytes per frame */

     } else if (enc->codec_id == AV_CODEC_ID_AAC) {
         blkalign = 768 * enc->channels; /* maximum bytes per frame */
     } else if (enc->codec_id == AV_CODEC_ID_G723_1) {
         blkalign = 24;

     } else if (enc->block_align != 0) { /* specified by the codec */
         blkalign = enc->block_align;
     } else
         blkalign = bps * enc->channels / av_gcd(8, bps);
     if (enc->codec_id == AV_CODEC_ID_PCM_U8 ||
         enc->codec_id == AV_CODEC_ID_PCM_S24LE ||
         enc->codec_id == AV_CODEC_ID_PCM_S32LE ||
         enc->codec_id == AV_CODEC_ID_PCM_F32LE ||
         enc->codec_id == AV_CODEC_ID_PCM_F64LE ||
         enc->codec_id == AV_CODEC_ID_PCM_S16LE) {
         bytespersec = enc->sample_rate * blkalign;

     } else if (enc->codec_id == AV_CODEC_ID_G723_1) {
         bytespersec = 800;

     } else {
         bytespersec = enc->bit_rate / 8;
     }
     avio_wl32(pb, bytespersec); /* bytes per second */
     avio_wl16(pb, blkalign);    /* block align */
     avio_wl16(pb, bps);         /* bits per sample */
     if (enc->codec_id == AV_CODEC_ID_MP3) {
         bytestream_put_le16(&riff_extradata, 1);    /* wID */
         bytestream_put_le32(&riff_extradata, 2);    /* fdwFlags */
         bytestream_put_le16(&riff_extradata, 1152); /* nBlockSize */
         bytestream_put_le16(&riff_extradata, 1);    /* nFramesPerBlock */
         bytestream_put_le16(&riff_extradata, 1393); /* nCodecDelay */
     } else if (enc->codec_id == AV_CODEC_ID_MP2) {
         /* fwHeadLayer */
         bytestream_put_le16(&riff_extradata, 2);
         /* dwHeadBitrate */
         bytestream_put_le32(&riff_extradata, enc->bit_rate);
         /* fwHeadMode */
         bytestream_put_le16(&riff_extradata, enc->channels == 2 ? 1 : 8);
         /* fwHeadModeExt */
         bytestream_put_le16(&riff_extradata, 0);
         /* wHeadEmphasis */
         bytestream_put_le16(&riff_extradata, 1);
         /* fwHeadFlags */
         bytestream_put_le16(&riff_extradata, 16);
         /* dwPTSLow */
         bytestream_put_le32(&riff_extradata, 0);
         /* dwPTSHigh */
         bytestream_put_le32(&riff_extradata, 0);

     } else if (enc->codec_id == AV_CODEC_ID_G723_1) {
         bytestream_put_le32(&riff_extradata, 0x9ace0002); /* extradata needed for msacm g723.1 codec */
         bytestream_put_le32(&riff_extradata, 0xaea2f732);
         bytestream_put_le16(&riff_extradata, 0xacde);

     } else if (enc->codec_id == AV_CODEC_ID_GSM_MS ||
                enc->codec_id == AV_CODEC_ID_ADPCM_IMA_WAV) {
         /* wSamplesPerBlock */
         bytestream_put_le16(&riff_extradata, frame_size);
     } else if (enc->extradata_size) {
         riff_extradata_start = enc->extradata;
         riff_extradata       = enc->extradata + enc->extradata_size;
     }
     /* write WAVEFORMATEXTENSIBLE extensions */
     if (waveformatextensible) {

         int write_channel_mask = enc->strict_std_compliance < FF_COMPLIANCE_NORMAL ||
                                  enc->channel_layout < 0x40000;

         /* 22 is WAVEFORMATEXTENSIBLE size */
         avio_wl16(pb, riff_extradata - riff_extradata_start + 22);
         /* ValidBitsPerSample || SamplesPerBlock || Reserved */
         avio_wl16(pb, bps);
         /* dwChannelMask */

         avio_wl32(pb, write_channel_mask ? enc->channel_layout : 0);

         /* GUID + next 3 */

         if (enc->codec_id == AV_CODEC_ID_EAC3) {
             ff_put_guid(pb, get_codec_guid(enc->codec_id, ff_codec_wav_guids));
         } else {

         avio_wl32(pb, enc->codec_tag);
         avio_wl32(pb, 0x00100000);
         avio_wl32(pb, 0xAA000080);
         avio_wl32(pb, 0x719B3800);

         }

     } else if ((flags & FF_PUT_WAV_HEADER_FORCE_WAVEFORMATEX) ||
                enc->codec_tag != 0x0001 /* PCM */ ||
                riff_extradata - riff_extradata_start) {
         /* WAVEFORMATEX */

         avio_wl16(pb, riff_extradata - riff_extradata_start); /* cbSize */

     } /* else PCMWAVEFORMAT */

     avio_write(pb, riff_extradata_start, riff_extradata - riff_extradata_start);

     hdrsize = avio_tell(pb) - hdrstart;

     if (hdrsize & 1) {
         hdrsize++;
         avio_w8(pb, 0);
     }
 
     return hdrsize;
 }
 
 /* BITMAPINFOHEADER header */
 void ff_put_bmp_header(AVIOContext *pb, AVCodecContext *enc,

                        const AVCodecTag *tags, int for_asf, int ignore_extradata)

 {

     int keep_height = enc->extradata_size >= 9 &&
                       !memcmp(enc->extradata + enc->extradata_size - 9, "BottomUp", 9);
     int extradata_size = enc->extradata_size - 9*keep_height;
 

     /* size */

     avio_wl32(pb, 40 + (ignore_extradata ? 0 :extradata_size));

     avio_wl32(pb, enc->width);
     //We always store RGB TopDown

     avio_wl32(pb, enc->codec_tag || keep_height ? enc->height : -enc->height);

     /* planes */
     avio_wl16(pb, 1);
     /* depth */
     avio_wl16(pb, enc->bits_per_coded_sample ? enc->bits_per_coded_sample : 24);
     /* compression type */
     avio_wl32(pb, enc->codec_tag);

     avio_wl32(pb, (enc->width * enc->height * (enc->bits_per_coded_sample ? enc->bits_per_coded_sample : 24)+7) / 8);

     avio_wl32(pb, 0);
     avio_wl32(pb, 0);
     avio_wl32(pb, 0);
     avio_wl32(pb, 0);
 

     if (!ignore_extradata) {

         avio_write(pb, enc->extradata, extradata_size);

         if (!for_asf && extradata_size & 1)

             avio_w8(pb, 0);

     }

 }
 

 void ff_parse_specific_params(AVStream *st, int *au_rate,

                               int *au_ssize, int *au_scale)
 {

     AVCodecContext *codec = st->codec;

     int gcd;
     int audio_frame_size;
 
     /* We use the known constant frame size for the codec if known, otherwise
      * fall back on using AVCodecContext.frame_size, which is not as reliable
      * for indicating packet duration. */

     audio_frame_size = av_get_audio_frame_duration(codec, 0);

     if (!audio_frame_size)

         audio_frame_size = codec->frame_size;

     *au_ssize = codec->block_align;
     if (audio_frame_size && codec->sample_rate) {

         *au_scale = audio_frame_size;

         *au_rate  = codec->sample_rate;
     } else if (codec->codec_type == AVMEDIA_TYPE_VIDEO ||
                codec->codec_type == AVMEDIA_TYPE_DATA ||
                codec->codec_type == AVMEDIA_TYPE_SUBTITLE) {

         *au_scale = st->time_base.num;
         *au_rate  = st->time_base.den;

     } else {

         *au_scale = codec->block_align ? codec->block_align * 8 : 8;
         *au_rate  = codec->bit_rate ? codec->bit_rate :
                     8 * codec->sample_rate;

     }
     gcd        = av_gcd(*au_scale, *au_rate);
     *au_scale /= gcd;
     *au_rate  /= gcd;
 }
 
 void ff_riff_write_info_tag(AVIOContext *pb, const char *tag, const char *str)
 {
     int len = strlen(str);
     if (len > 0) {
         len++;
         ffio_wfourcc(pb, tag);
         avio_wl32(pb, len);
         avio_put_str(pb, str);
         if (len & 1)
             avio_w8(pb, 0);
     }
 }
 
 static const char riff_tags[][5] = {
     "IARL", "IART", "ICMS", "ICMT", "ICOP", "ICRD", "ICRP", "IDIM", "IDPI",
     "IENG", "IGNR", "IKEY", "ILGT", "ILNG", "IMED", "INAM", "IPLT", "IPRD",

     "IPRT", "ITRK", "ISBJ", "ISFT", "ISHP", "ISMP", "ISRC", "ISRF", "ITCH",

     { 0 }
 };
 
 static int riff_has_valid_tags(AVFormatContext *s)
 {
     int i;
 
     for (i = 0; *riff_tags[i]; i++)
         if (av_dict_get(s->metadata, riff_tags[i], NULL, AV_DICT_MATCH_CASE))
             return 1;
 
     return 0;
 }
 
 void ff_riff_write_info(AVFormatContext *s)
 {
     AVIOContext *pb = s->pb;
     int i;
     int64_t list_pos;
     AVDictionaryEntry *t = NULL;
 
     ff_metadata_conv(&s->metadata, ff_riff_info_conv, NULL);
 
     /* writing empty LIST is not nice and may cause problems */
     if (!riff_has_valid_tags(s))
         return;
 
     list_pos = ff_start_tag(pb, "LIST");
     ffio_wfourcc(pb, "INFO");
     for (i = 0; *riff_tags[i]; i++)
         if ((t = av_dict_get(s->metadata, riff_tags[i],
                              NULL, AV_DICT_MATCH_CASE)))
             ff_riff_write_info_tag(s->pb, t->key, t->value);
     ff_end_tag(pb, list_pos);
 }

 
 void ff_put_guid(AVIOContext *s, const ff_asf_guid *g)
 {
     av_assert0(sizeof(*g) == 16);
     avio_write(s, *g, sizeof(*g));
 }
 
 const ff_asf_guid *get_codec_guid(enum AVCodecID id, const AVCodecGuid *av_guid)
 {
     int i;
     for (i = 0; av_guid[i].id != AV_CODEC_ID_NONE; i++) {
         if (id == av_guid[i].id)
             return &(av_guid[i].guid);
     }
     return NULL;
 }