/*
  * Copyright (c) 2012 Clément Bœsch
  *
  * 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
  * MPlayer subtitles format demuxer
  */
 
 #include "avformat.h"
 #include "internal.h"
 #include "subtitles.h"
 
 typedef struct {
     FFDemuxSubtitlesQueue q;
 } MPSubContext;
 
 static int mpsub_probe(AVProbeData *p)
 {
     const char *ptr     = p->buf;
     const char *ptr_end = p->buf + p->buf_size;
 
     while (ptr < ptr_end) {

         int inc;
 

         if (!memcmp(ptr, "FORMAT=TIME", 11))

             return AVPROBE_SCORE_EXTENSION;

         if (!memcmp(ptr, "FORMAT=", 7))
             return AVPROBE_SCORE_EXTENSION / 3;

         inc = ff_subtitles_next_line(ptr);
         if (!inc)
             break;
         ptr += inc;

     }
     return 0;
 }
 
 static int mpsub_read_header(AVFormatContext *s)
 {
     MPSubContext *mpsub = s->priv_data;
     AVStream *st;
     AVBPrint buf;
     AVRational pts_info = (AVRational){ 100, 1 }; // ts based by default
     int res = 0;
     float multiplier = 100.0;
     float current_pts = 0;
 
     av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
 
     while (!url_feof(s->pb)) {
         char line[1024];
         float start, duration;
         int fps, len = ff_get_line(s->pb, line, sizeof(line));
 
         if (!len)
             break;
 
         line[strcspn(line, "\r\n")] = 0;
 
         if (sscanf(line, "FORMAT=%d", &fps) == 1 && fps > 3 && fps < 100) {
             /* frame based timing */
             pts_info = (AVRational){ fps, 1 };
             multiplier = 1.0;
         } else if (sscanf(line, "%f %f", &start, &duration) == 2) {
             AVPacket *sub;
             const int64_t pos = avio_tell(s->pb);
 
             ff_subtitles_read_chunk(s->pb, &buf);
             if (buf.len) {
                 sub = ff_subtitles_queue_insert(&mpsub->q, buf.str, buf.len, 0);
                 if (!sub) {
                     res = AVERROR(ENOMEM);
                     goto end;
                 }
                 sub->pts = (int64_t)(current_pts + start*multiplier);
                 sub->duration = (int)(duration * multiplier);
                 current_pts += (start + duration) * multiplier;
                 sub->pos = pos;
             }
         }
     }
 
     st = avformat_new_stream(s, NULL);
     if (!st)
         return AVERROR(ENOMEM);
     avpriv_set_pts_info(st, 64, pts_info.den, pts_info.num);
     st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
     st->codec->codec_id   = AV_CODEC_ID_TEXT;
 
     ff_subtitles_queue_finalize(&mpsub->q);
 
 end:
     av_bprint_finalize(&buf, NULL);
     return res;
 }
 
 static int mpsub_read_packet(AVFormatContext *s, AVPacket *pkt)
 {
     MPSubContext *mpsub = s->priv_data;
     return ff_subtitles_queue_read_packet(&mpsub->q, pkt);
 }
 
 static int mpsub_read_seek(AVFormatContext *s, int stream_index,
                            int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
 {
     MPSubContext *mpsub = s->priv_data;
     return ff_subtitles_queue_seek(&mpsub->q, s, stream_index,
                                    min_ts, ts, max_ts, flags);
 }
 
 static int mpsub_read_close(AVFormatContext *s)
 {
     MPSubContext *mpsub = s->priv_data;
     ff_subtitles_queue_clean(&mpsub->q);
     return 0;
 }
 
 AVInputFormat ff_mpsub_demuxer = {
     .name           = "mpsub",
     .long_name      = NULL_IF_CONFIG_SMALL("MPlayer subtitles"),
     .priv_data_size = sizeof(MPSubContext),
     .read_probe     = mpsub_probe,
     .read_header    = mpsub_read_header,
     .read_packet    = mpsub_read_packet,
     .read_seek2     = mpsub_read_seek,
     .read_close     = mpsub_read_close,
     .extensions     = "sub",
 };