/*
  * Silicon Graphics Movie demuxer
  * Copyright (c) 2012 Peter Ross
  *
  * 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
  * Silicon Graphics Movie demuxer
  */
 
 #include "libavutil/eval.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/rational.h"
 #include "avformat.h"
 #include "internal.h"
 
 typedef struct {
     int nb_video_tracks;
     int nb_audio_tracks;
 
     int eof_count;        /**< number of streams that have finished */
     int stream_index;     /**< current stream index */
     int frame[2];         /**< frame nb for current stream */
 } MvContext;
 
 #define AUDIO_FORMAT_SIGNED 401
 
 static int mv_probe(AVProbeData *p)
 {
     if (AV_RB32(p->buf) == MKBETAG('M','O','V','I') && AV_RB16(p->buf + 4) < 3)
         return AVPROBE_SCORE_MAX;
     return 0;
 }
 
 static char * var_read_string(AVIOContext *pb, int size)
 {
     char *str = av_malloc(size + 1);
     int n;
     if (!str)
         return NULL;
     n = avio_get_str(pb, size, str, size + 1);
     if (n < size)
          avio_skip(pb, size - n);
     return str;
 }
 
 static int var_read_int(AVIOContext *pb, int size)
 {
     int v;
     char * s = var_read_string(pb, size);
     if (!s || sscanf(s, "%d", &v) != 1)
         v = 0;
     av_free(s);
     return v;
 }
 
 static AVRational var_read_float(AVIOContext *pb, int size)
 {
     AVRational v;
     char * s = var_read_string(pb, size);
     if (!s)
         return (AVRational){0, 0};
     v = av_d2q(av_strtod(s, NULL), INT_MAX);
     av_free(s);
     return v;
 }
 
 static void var_read_metadata(AVFormatContext *avctx, const char *tag, int size)
 {
     char *value = var_read_string(avctx->pb, size);
     if (value)
         av_dict_set(&avctx->metadata, tag, value, AV_DICT_DONT_STRDUP_VAL);
 }
 
 /**
  * Parse global variable
  * @return < 0 if unknown
  */
 static int parse_global_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
 {
     MvContext *mv = avctx->priv_data;
     AVIOContext *pb = avctx->pb;
     if (!strcmp(name, "__NUM_I_TRACKS")) {
         mv->nb_video_tracks = var_read_int(pb, size);
     } else if (!strcmp(name, "__NUM_A_TRACKS")) {
         mv->nb_audio_tracks = var_read_int(pb, size);
     } else if (!strcmp(name, "COMMENT") || !strcmp(name, "TITLE")) {
         var_read_metadata(avctx, name, size);
     } else if (!strcmp(name, "LOOP_MODE") || !strcmp(name, "NUM_LOOPS") || !strcmp(name, "OPTIMIZED")) {
         avio_skip(pb, size); // ignore
     } else
         return -1;
 
     return 0;
 }
 
 /**
  * Parse audio variable
  * @return < 0 if unknown
  */
 static int parse_audio_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
 {
     AVIOContext *pb = avctx->pb;
     if (!strcmp(name, "__DIR_COUNT")) {
         st->nb_frames = var_read_int(pb, size);
     } else if (!strcmp(name, "AUDIO_FORMAT")) {
         st->codec->codec_id = var_read_int(pb, size);
     } else if (!strcmp(name, "COMPRESSION")) {
         st->codec->codec_tag = var_read_int(pb, size);
     } else if (!strcmp(name, "DEFAULT_VOL")) {
         var_read_metadata(avctx, name, size);
     } else if (!strcmp(name, "NUM_CHANNELS")) {
         st->codec->channels = var_read_int(pb, size);
         st->codec->channel_layout = (st->codec->channels == 1) ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO;
     } else if (!strcmp(name, "SAMPLE_RATE")) {
         st->codec->sample_rate = var_read_int(pb, size);
         avpriv_set_pts_info(st, 33, 1, st->codec->sample_rate);
     } else if (!strcmp(name, "SAMPLE_WIDTH")) {
         st->codec->bits_per_coded_sample = var_read_int(pb, size) * 8;
     } else
         return -1;
     return 0;
 }
 
 /**
  * Parse video variable
  * @return < 0 if unknown
  */
 static int parse_video_var(AVFormatContext *avctx, AVStream *st, const char *name, int size)
 {
     AVIOContext *pb = avctx->pb;
     if (!strcmp(name, "__DIR_COUNT")) {
         st->nb_frames = st->duration = var_read_int(pb, size);
     } else if (!strcmp(name, "COMPRESSION")) {
         char * str = var_read_string(pb, size);
         if (!strcmp(str, "1")) {
             st->codec->codec_id = AV_CODEC_ID_MVC1;
         } else if (!strcmp(str, "2")) {
             st->codec->pix_fmt  = AV_PIX_FMT_ABGR;
             st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
         } else if (!strcmp(str, "3")) {
             st->codec->codec_id = AV_CODEC_ID_SGIRLE;
         } else if (!strcmp(str, "10")) {
             st->codec->codec_id = AV_CODEC_ID_MJPEG;
         } else if (!strcmp(str, "MVC2")) {
             st->codec->codec_id = AV_CODEC_ID_MVC2;
         } else {
             av_log_ask_for_sample(avctx, "unknown video compression %s\n", str);
         }
         av_free(str);
     } else if (!strcmp(name, "FPS")) {
         st->time_base = av_inv_q(var_read_float(pb, size));
     } else if (!strcmp(name, "HEIGHT")) {
         st->codec->height = var_read_int(pb, size);
     } else if (!strcmp(name, "PIXEL_ASPECT")) {
         st->sample_aspect_ratio = var_read_float(pb, size);
         av_reduce(&st->sample_aspect_ratio.num, &st->sample_aspect_ratio.den,
                   st->sample_aspect_ratio.num, st->sample_aspect_ratio.den, INT_MAX);
     } else if (!strcmp(name, "WIDTH")) {
         st->codec->width = var_read_int(pb, size);
     } else if (!strcmp(name, "ORIENTATION")) {
         if (var_read_int(pb, size) == 1101) {
             st->codec->extradata       = av_strdup("BottomUp");
             st->codec->extradata_size  = 9;
         }
     } else if (!strcmp(name, "Q_SPATIAL") || !strcmp(name, "Q_TEMPORAL")) {
         var_read_metadata(avctx, name, size);
     } else if (!strcmp(name, "INTERLACING") || !strcmp(name, "PACKING")) {
         avio_skip(pb, size); // ignore
     } else
         return -1;
     return 0;
 }
 
 static void read_table(AVFormatContext *avctx, AVStream *st, int (*parse)(AVFormatContext *avctx, AVStream *st, const char *name, int size))
 {
     int count, i;
     AVIOContext *pb = avctx->pb;
     avio_skip(pb, 4);
     count = avio_rb32(pb);
     avio_skip(pb, 4);
     for (i = 0; i < count; i++) {
         char name[17];
         int size;
         avio_read(pb, name, 16);
         name[sizeof(name) - 1] = 0;
         size = avio_rb32(pb);
         if (parse(avctx, st, name, size) < 0) {
             av_log_ask_for_sample(avctx, "unknown variable %s\n", name);
             avio_skip(pb, size);
         }
     }
 }
 
 static void read_index(AVIOContext *pb, AVStream *st)
 {
     uint64_t timestamp = 0;
     int i;
     for (i = 0; i < st->nb_frames; i++) {
         uint32_t pos  = avio_rb32(pb);
         uint32_t size = avio_rb32(pb);
         avio_skip(pb, 8);
         av_add_index_entry(st, pos, timestamp, size, 0, AVINDEX_KEYFRAME);
         if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
             timestamp += size / (st->codec->channels * 2);
         } else {
             timestamp++;
         }
     }
 }
 
 static int mv_read_header(AVFormatContext *avctx)
 {
     MvContext *mv = avctx->priv_data;
     AVIOContext *pb = avctx->pb;

     AVStream *ast = NULL, *vst = NULL; //initialization to suppress warning

     int version, i;
 
     avio_skip(pb, 4);
 
     version = avio_rb16(pb);
     if (version == 2) {
         uint64_t timestamp;
         int v;
         avio_skip(pb, 22);
 
         /* allocate audio track first to prevent unnecessary seeking
            (audio packet always precede video packet for a given frame) */
         ast = avformat_new_stream(avctx, NULL);
         if (!ast)
             return AVERROR(ENOMEM);
 
         vst = avformat_new_stream(avctx, NULL);
         if (!vst)
             return AVERROR(ENOMEM);
         vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
         vst->time_base = (AVRational){1, 15};
         vst->nb_frames = avio_rb32(pb);
         v = avio_rb32(pb);
         switch (v) {
         case 1:
             vst->codec->codec_id = AV_CODEC_ID_MVC1;
             break;
         case 2:
             vst->codec->pix_fmt  = AV_PIX_FMT_ARGB;
             vst->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
             break;
         default:
             av_log_ask_for_sample(avctx, "unknown video compression %i\n", v);
             break;
         }
         vst->codec->codec_tag = 0;
         vst->codec->width     = avio_rb32(pb);
         vst->codec->height    = avio_rb32(pb);
         avio_skip(pb, 12);
 
         ast->codec->codec_type     = AVMEDIA_TYPE_AUDIO;
         ast->nb_frames             = vst->nb_frames;
         ast->codec->sample_rate    = avio_rb32(pb);
         avpriv_set_pts_info(ast, 33, 1, ast->codec->sample_rate);
         ast->codec->channels       = avio_rb32(pb);
         ast->codec->channel_layout = (ast->codec->channels == 1) ? AV_CH_LAYOUT_MONO : AV_CH_LAYOUT_STEREO;
         v = avio_rb32(pb);
         if (v == AUDIO_FORMAT_SIGNED) {
             ast->codec->codec_id = AV_CODEC_ID_PCM_S16BE;
         } else {
             av_log_ask_for_sample(avctx, "unknown audio compression (format %i)\n", v);
         }
 
         avio_skip(pb, 12);
         var_read_metadata(avctx, "title", 0x80);
         var_read_metadata(avctx, "comment", 0x100);
         avio_skip(pb, 0x80);
 
         timestamp = 0;
         for (i = 0; i < vst->nb_frames; i++) {
             uint32_t pos   = avio_rb32(pb);
             uint32_t asize = avio_rb32(pb);
             uint32_t vsize = avio_rb32(pb);
             avio_skip(pb, 8);
             av_add_index_entry(ast, pos,         timestamp, asize, 0, AVINDEX_KEYFRAME);
             av_add_index_entry(vst, pos + asize, i,         vsize, 0, AVINDEX_KEYFRAME);
             timestamp += asize / (ast->codec->channels * 2);
         }
     } else if (!version && avio_rb16(pb) == 3) {
         avio_skip(pb, 4);
 
         read_table(avctx, NULL, parse_global_var);
 
         if (mv->nb_audio_tracks > 1) {
             av_log_ask_for_sample(avctx, "multiple audio streams\n");
             return AVERROR_PATCHWELCOME;
         } else if (mv->nb_audio_tracks) {
             ast = avformat_new_stream(avctx, NULL);
             if (!ast)
                 return AVERROR(ENOMEM);
             ast->codec->codec_type = AVMEDIA_TYPE_AUDIO;
             /* temporarily store compression value in codec_tag; format value in codec_id */
             read_table(avctx, ast, parse_audio_var);
             if (ast->codec->codec_tag == 100 && ast->codec->codec_id == AUDIO_FORMAT_SIGNED && ast->codec->bits_per_coded_sample == 16) {
                 ast->codec->codec_id = AV_CODEC_ID_PCM_S16BE;
             } else {
                 av_log_ask_for_sample(avctx, "unknown audio compression %i (format %i, width %i)\n",
                     ast->codec->codec_tag, ast->codec->codec_id, ast->codec->bits_per_coded_sample);
                 ast->codec->codec_id = AV_CODEC_ID_NONE;
             }
             ast->codec->codec_tag = 0;
         }
 
         if (mv->nb_video_tracks > 1) {
             av_log_ask_for_sample(avctx, "multiple video streams\n");
             return AVERROR_PATCHWELCOME;
         } else if (mv->nb_video_tracks) {
             vst = avformat_new_stream(avctx, NULL);
             if (!vst)
                 return AVERROR(ENOMEM);
             vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
             read_table(avctx, vst, parse_video_var);
         }
 
         if (mv->nb_audio_tracks)
             read_index(pb, ast);
 
         if (mv->nb_video_tracks)
             read_index(pb, vst);
     } else {
         av_log_ask_for_sample(avctx, "unknown version %i\n", version);
         return AVERROR_PATCHWELCOME;
     }
 
     return 0;
 }
 
 static int mv_read_packet(AVFormatContext *avctx, AVPacket *pkt)
 {
     MvContext *mv = avctx->priv_data;
     AVIOContext *pb = avctx->pb;
     AVStream *st = avctx->streams[mv->stream_index];
     const AVIndexEntry *index;
     int frame = mv->frame[mv->stream_index];

     int64_t ret;

     uint64_t pos;
 
     if (frame  < st->nb_frames) {
         index = &st->index_entries[frame];
         pos = avio_tell(pb);
         if (index->pos > pos)
             avio_skip(pb, index->pos - pos);
         else if (index->pos < pos) {
             if (!pb->seekable)
                 return AVERROR(EIO);
             ret = avio_seek(pb, index->pos, SEEK_SET);
             if (ret < 0)
                 return ret;
         }
         ret = av_get_packet(pb, pkt, index->size);
         if (ret < 0)
             return ret;
 
         pkt->stream_index = mv->stream_index;
         pkt->pts = index->timestamp;
         pkt->flags |= AV_PKT_FLAG_KEY;
 
         mv->frame[mv->stream_index]++;
         mv->eof_count = 0;
     } else {
         mv->eof_count++;
         if (mv->eof_count >= avctx->nb_streams)
             return AVERROR_EOF;
     }
 
     mv->stream_index++;
     if (mv->stream_index >= avctx->nb_streams)
         mv->stream_index = 0;
 
     return 0;
 }
 
 static int mv_read_seek(AVFormatContext *avctx, int stream_index, int64_t timestamp, int flags)
 {
     MvContext *mv = avctx->priv_data;
     AVStream *st = avctx->streams[stream_index];
     int frame, i;
 
     if ((flags & AVSEEK_FLAG_FRAME) || (flags & AVSEEK_FLAG_BYTE))
         return AVERROR(ENOSYS);
 
     if (!avctx->pb->seekable)
         return AVERROR(EIO);
 
     frame = av_index_search_timestamp(st, timestamp, flags);
     if (frame < 0)
         return -1;
 
     for (i = 0; i < avctx->nb_streams; i++)
         mv->frame[i] = frame;
     return 0;
 }
 
 AVInputFormat ff_mv_demuxer = {
     .name           = "mv",
     .long_name      = NULL_IF_CONFIG_SMALL("Silicon Graphics Movie"),
     .priv_data_size = sizeof(MvContext),
     .read_probe     = mv_probe,
     .read_header    = mv_read_header,
     .read_packet    = mv_read_packet,
     .read_seek      = mv_read_seek,
 };