/*
  * Westwood Studios VQA Format Demuxer
  * Copyright (c) 2003 The ffmpeg Project
  *

  * 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
  */
 
 /**
  * @file
  * Westwood Studios VQA file demuxer
  * by Mike Melanson (melanson@pcisys.net)
  * for more information on the Westwood file formats, visit:
  *   http://www.pcisys.net/~melanson/codecs/
  *   http://www.geocities.com/SiliconValley/8682/aud3.txt
  */
 
 #include "libavutil/intreadwrite.h"
 #include "avformat.h"
 #include "internal.h"
 
 #define FORM_TAG MKBETAG('F', 'O', 'R', 'M')
 #define WVQA_TAG MKBETAG('W', 'V', 'Q', 'A')
 #define VQHD_TAG MKBETAG('V', 'Q', 'H', 'D')
 #define FINF_TAG MKBETAG('F', 'I', 'N', 'F')
 #define SND0_TAG MKBETAG('S', 'N', 'D', '0')
 #define SND1_TAG MKBETAG('S', 'N', 'D', '1')
 #define SND2_TAG MKBETAG('S', 'N', 'D', '2')
 #define VQFR_TAG MKBETAG('V', 'Q', 'F', 'R')
 
 /* don't know what these tags are for, but acknowledge their existence */
 #define CINF_TAG MKBETAG('C', 'I', 'N', 'F')
 #define CINH_TAG MKBETAG('C', 'I', 'N', 'H')
 #define CIND_TAG MKBETAG('C', 'I', 'N', 'D')
 #define PINF_TAG MKBETAG('P', 'I', 'N', 'F')
 #define PINH_TAG MKBETAG('P', 'I', 'N', 'H')
 #define PIND_TAG MKBETAG('P', 'I', 'N', 'D')
 #define CMDS_TAG MKBETAG('C', 'M', 'D', 'S')
 
 #define VQA_HEADER_SIZE 0x2A
 #define VQA_PREAMBLE_SIZE 8
 
 typedef struct WsVqaDemuxContext {

     int version;
     int bps;
     int channels;
     int sample_rate;

     int audio_stream_index;
     int video_stream_index;
 } WsVqaDemuxContext;
 
 static int wsvqa_probe(AVProbeData *p)
 {
     /* need 12 bytes to qualify */
     if (p->buf_size < 12)
         return 0;
 
     /* check for the VQA signatures */
     if ((AV_RB32(&p->buf[0]) != FORM_TAG) ||
         (AV_RB32(&p->buf[8]) != WVQA_TAG))
         return 0;
 
     return AVPROBE_SCORE_MAX;
 }
 

 static int wsvqa_read_header(AVFormatContext *s)

 {
     WsVqaDemuxContext *wsvqa = s->priv_data;
     AVIOContext *pb = s->pb;
     AVStream *st;
     unsigned char *header;
     unsigned char scratch[VQA_PREAMBLE_SIZE];
     unsigned int chunk_tag;
     unsigned int chunk_size;

     int fps;

 
     /* initialize the video decoder stream */
     st = avformat_new_stream(s, NULL);
     if (!st)
         return AVERROR(ENOMEM);

     st->start_time = 0;

     wsvqa->video_stream_index = st->index;
     st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

     st->codec->codec_id = AV_CODEC_ID_WS_VQA;

     st->codec->codec_tag = 0;  /* no fourcc */
 
     /* skip to the start of the VQA header */
     avio_seek(pb, 20, SEEK_SET);
 
     /* the VQA header needs to go to the decoder */
     st->codec->extradata_size = VQA_HEADER_SIZE;
     st->codec->extradata = av_mallocz(VQA_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
     header = (unsigned char *)st->codec->extradata;
     if (avio_read(pb, st->codec->extradata, VQA_HEADER_SIZE) !=
         VQA_HEADER_SIZE) {
         return AVERROR(EIO);
     }
     st->codec->width = AV_RL16(&header[6]);
     st->codec->height = AV_RL16(&header[8]);

     fps = header[12];

     st->nb_frames =
     st->duration  = AV_RL16(&header[4]);

     if (fps < 1 || fps > 30) {
         av_log(s, AV_LOG_ERROR, "invalid fps: %d\n", fps);
         return AVERROR_INVALIDDATA;
     }
     avpriv_set_pts_info(st, 64, 1, fps);

     wsvqa->version      = AV_RL16(&header[ 0]);
     wsvqa->sample_rate  = AV_RL16(&header[24]);
     wsvqa->channels     = header[26];
     wsvqa->bps          = header[27];
     wsvqa->audio_stream_index = -1;

     s->ctx_flags |= AVFMTCTX_NOHEADER;

 
     /* there are 0 or more chunks before the FINF chunk; iterate until
      * FINF has been skipped and the file will be ready to be demuxed */
     do {

         if (avio_read(pb, scratch, VQA_PREAMBLE_SIZE) != VQA_PREAMBLE_SIZE)

             return AVERROR(EIO);
         chunk_tag = AV_RB32(&scratch[0]);
         chunk_size = AV_RB32(&scratch[4]);
 
         /* catch any unknown header tags, for curiousity */
         switch (chunk_tag) {
         case CINF_TAG:
         case CINH_TAG:
         case CIND_TAG:
         case PINF_TAG:
         case PINH_TAG:
         case PIND_TAG:
         case FINF_TAG:
         case CMDS_TAG:
             break;
 
         default:
             av_log (s, AV_LOG_ERROR, " note: unknown chunk seen (%c%c%c%c)\n",
                 scratch[0], scratch[1],
                 scratch[2], scratch[3]);
             break;
         }
 
         avio_skip(pb, chunk_size);
     } while (chunk_tag != FINF_TAG);
 
     return 0;
 }
 
 static int wsvqa_read_packet(AVFormatContext *s,
                              AVPacket *pkt)
 {
     WsVqaDemuxContext *wsvqa = s->priv_data;
     AVIOContext *pb = s->pb;
     int ret = -1;
     unsigned char preamble[VQA_PREAMBLE_SIZE];
     unsigned int chunk_type;
     unsigned int chunk_size;
     int skip_byte;
 
     while (avio_read(pb, preamble, VQA_PREAMBLE_SIZE) == VQA_PREAMBLE_SIZE) {
         chunk_type = AV_RB32(&preamble[0]);
         chunk_size = AV_RB32(&preamble[4]);

         skip_byte = chunk_size & 0x01;
 

         if ((chunk_type == SND0_TAG) || (chunk_type == SND1_TAG) ||
             (chunk_type == SND2_TAG) || (chunk_type == VQFR_TAG)) {

             ret= av_get_packet(pb, pkt, chunk_size);
             if (ret<0)

                 return AVERROR(EIO);
 

             switch (chunk_type) {
             case SND0_TAG:
             case SND1_TAG:
             case SND2_TAG:
                 if (wsvqa->audio_stream_index == -1) {
                     AVStream *st = avformat_new_stream(s, NULL);
                     if (!st)
                         return AVERROR(ENOMEM);
 
                     wsvqa->audio_stream_index = st->index;
                     if (!wsvqa->sample_rate)
                         wsvqa->sample_rate = 22050;
                     if (!wsvqa->channels)
                         wsvqa->channels = 1;
                     if (!wsvqa->bps)
                         wsvqa->bps = 8;
                     st->codec->sample_rate = wsvqa->sample_rate;
                     st->codec->bits_per_coded_sample = wsvqa->bps;
                     st->codec->channels = wsvqa->channels;
                     st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
 
                     avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
 
                     switch (chunk_type) {
                     case SND0_TAG:
                         if (wsvqa->bps == 16)

                             st->codec->codec_id = AV_CODEC_ID_PCM_S16LE;

                         else

                             st->codec->codec_id = AV_CODEC_ID_PCM_U8;

                         break;
                     case SND1_TAG:

                         st->codec->codec_id = AV_CODEC_ID_WESTWOOD_SND1;

                         break;
                     case SND2_TAG:

                         st->codec->codec_id = AV_CODEC_ID_ADPCM_IMA_WS;

                         st->codec->extradata_size = 2;
                         st->codec->extradata = av_mallocz(2 + FF_INPUT_BUFFER_PADDING_SIZE);
                         if (!st->codec->extradata)
                             return AVERROR(ENOMEM);
                         AV_WL16(st->codec->extradata, wsvqa->version);
                         break;
                     }
                 }
 

                 pkt->stream_index = wsvqa->audio_stream_index;

                 switch (chunk_type) {
                 case SND1_TAG:
                     /* unpacked size is stored in header */

                     if(pkt->data)
                         pkt->duration = AV_RL16(pkt->data) / wsvqa->channels;

                     break;
                 case SND2_TAG:
                     /* 2 samples/byte, 1 or 2 samples per frame depending on stereo */
                     pkt->duration = (chunk_size * 2) / wsvqa->channels;
                     break;
                 }
                 break;
             case VQFR_TAG:

                 pkt->stream_index = wsvqa->video_stream_index;

                 pkt->duration = 1;

                 break;

             }

             /* stay on 16-bit alignment */
             if (skip_byte)
                 avio_skip(pb, 1);
 
             return ret;
         } else {
             switch(chunk_type){
             case CMDS_TAG:
                 break;
             default:
                 av_log(s, AV_LOG_INFO, "Skipping unknown chunk 0x%08X\n", chunk_type);
             }
             avio_skip(pb, chunk_size + skip_byte);
         }
     }
 
     return ret;
 }
 
 AVInputFormat ff_wsvqa_demuxer = {
     .name           = "wsvqa",

     .long_name      = NULL_IF_CONFIG_SMALL("Westwood Studios VQA"),

     .priv_data_size = sizeof(WsVqaDemuxContext),
     .read_probe     = wsvqa_probe,
     .read_header    = wsvqa_read_header,
     .read_packet    = wsvqa_read_packet,
 };