/*
  * Creative Voice File muxer.
  * Copyright (c) 2006  Aurelien Jacobs <aurel@gnuage.org>
  *
  * 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 "voc.h"

 #include "internal.h"

 
 
 typedef struct voc_enc_context {
     int param_written;

 } VocEncContext;

 
 static int voc_write_header(AVFormatContext *s)
 {

     AVIOContext *pb = s->pb;

     AVCodecParameters *par = s->streams[0]->codecpar;

     const int header_size = 26;
     const int version = 0x0114;
 
     if (s->nb_streams != 1

         || s->streams[0]->codecpar->codec_type != AVMEDIA_TYPE_AUDIO)

         return AVERROR_PATCHWELCOME;

     if (!par->codec_tag && par->codec_id != AV_CODEC_ID_PCM_U8) {

         av_log(s, AV_LOG_ERROR, "unsupported codec\n");
         return AVERROR(EINVAL);
     }
 

     avio_write(pb, ff_voc_magic, sizeof(ff_voc_magic) - 1);
     avio_wl16(pb, header_size);
     avio_wl16(pb, version);
     avio_wl16(pb, ~version + 0x1234);

 
     return 0;
 }
 
 static int voc_write_packet(AVFormatContext *s, AVPacket *pkt)
 {

     VocEncContext *voc = s->priv_data;

     AVCodecParameters *par = s->streams[0]->codecpar;

     AVIOContext *pb = s->pb;

 
     if (!voc->param_written) {

         if (par->codec_tag > 3) {

             avio_w8(pb, VOC_TYPE_NEW_VOICE_DATA);
             avio_wl24(pb, pkt->size + 12);

             avio_wl32(pb, par->sample_rate);
             avio_w8(pb, par->bits_per_coded_sample);
             avio_w8(pb, par->channels);
             avio_wl16(pb, par->codec_tag);

             avio_wl32(pb, 0);

         } else {

             if (s->streams[0]->codecpar->channels > 1) {

                 avio_w8(pb, VOC_TYPE_EXTENDED);
                 avio_wl24(pb, 4);

                 avio_wl16(pb, 65536-(256000000 + par->sample_rate*par->channels/2)/(par->sample_rate*par->channels));

                 avio_w8(pb, par->codec_tag);
                 avio_w8(pb, par->channels - 1);

             }

             avio_w8(pb, VOC_TYPE_VOICE_DATA);
             avio_wl24(pb, pkt->size + 2);

             avio_w8(pb, 256 - (1000000 + par->sample_rate/2) / par->sample_rate);

             avio_w8(pb, par->codec_tag);

         }
         voc->param_written = 1;
     } else {

         avio_w8(pb, VOC_TYPE_VOICE_DATA_CONT);
         avio_wl24(pb, pkt->size);

     }
 

     avio_write(pb, pkt->data, pkt->size);

     return 0;
 }
 
 static int voc_write_trailer(AVFormatContext *s)
 {

     avio_w8(s->pb, 0);

     return 0;
 }
 

 AVOutputFormat ff_voc_muxer = {

     .name              = "voc",

     .long_name         = NULL_IF_CONFIG_SMALL("Creative Voice"),

     .mime_type         = "audio/x-voc",
     .extensions        = "voc",
     .priv_data_size    = sizeof(VocEncContext),

     .audio_codec       = AV_CODEC_ID_PCM_S16LE,

     .video_codec       = AV_CODEC_ID_NONE,

     .write_header      = voc_write_header,
     .write_packet      = voc_write_packet,
     .write_trailer     = voc_write_trailer,

     .codec_tag         = (const AVCodecTag* const []){ ff_voc_codec_tags, 0 },

     .flags             = AVFMT_NOTIMESTAMPS,

 };