/*
  * Copyright (c) 2015  Ganesh Ajjanagadde
  *
  * 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
  * G.729 audio parser
  *
  * Splits packets into individual blocks.
  */
 

 #include "libavutil/avassert.h"

 #include "parser.h"
 #include "g729.h"
 
 typedef struct G729ParseContext {
     ParseContext pc;
     int block_size;
     int duration;
     int remaining;
 } G729ParseContext;
 
 static int g729_parse(AVCodecParserContext *s1, AVCodecContext *avctx,
                      const uint8_t **poutbuf, int *poutbuf_size,
                      const uint8_t *buf, int buf_size)
 {
     G729ParseContext *s = s1->priv_data;
     ParseContext *pc = &s->pc;
     int next;
 
     if (!s->block_size) {

         av_assert1(avctx->codec_id == AV_CODEC_ID_G729);
         /* FIXME: replace this heuristic block_size with more precise estimate */
         s->block_size = (avctx->bit_rate < 8000) ? G729D_6K4_BLOCK_SIZE : G729_8K_BLOCK_SIZE;
         s->duration   = avctx->frame_size;

     }
 
     if (!s->remaining)
         s->remaining = s->block_size;
     if (s->remaining <= buf_size) {
         next = s->remaining;
         s->remaining = 0;
     } else {
         next = END_NOT_FOUND;
         s->remaining -= buf_size;
     }
 
     if (ff_combine_frame(pc, next, &buf, &buf_size) < 0 || !buf_size) {
         *poutbuf      = NULL;
         *poutbuf_size = 0;
         return buf_size;
     }
 
     s1->duration = s->duration;
 
     *poutbuf      = buf;
     *poutbuf_size = buf_size;
     return next;
 }
 
 AVCodecParser ff_g729_parser = {
     .codec_ids      = { AV_CODEC_ID_G729 },
     .priv_data_size = sizeof(G729ParseContext),
     .parser_parse   = g729_parse,
     .parser_close   = ff_parse_close,
 };