/*
  * True Audio (TTA) muxer
  * Copyright (c) 2016 James Almer
  *
  * 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 "libavutil/crc.h"
 #include "libavutil/intreadwrite.h"
 
 #include "apetag.h"
 #include "avformat.h"
 #include "avio_internal.h"
 #include "internal.h"
 
 typedef struct TTAMuxContext {
     AVIOContext *seek_table;

     AVPacketList *queue, *queue_end;

     uint32_t nb_samples;
     int frame_size;
     int last_frame;
 } TTAMuxContext;
 

 static int tta_init(AVFormatContext *s)

 {
     TTAMuxContext *tta = s->priv_data;

     AVCodecParameters *par;

 
     if (s->nb_streams != 1) {
         av_log(s, AV_LOG_ERROR, "Only one stream is supported\n");
         return AVERROR(EINVAL);
     }

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

     if (par->codec_id != AV_CODEC_ID_TTA) {
         av_log(s, AV_LOG_ERROR, "Unsupported codec\n");
         return AVERROR(EINVAL);
     }
     if (par->extradata && par->extradata_size < 22) {
         av_log(s, AV_LOG_ERROR, "Invalid TTA extradata\n");
         return AVERROR_INVALIDDATA;
     }
 

     /* Prevent overflow */
     if (par->sample_rate > 0x7FFFFFu) {
         av_log(s, AV_LOG_ERROR, "Sample rate too large\n");
         return AVERROR(EINVAL);
     }
     tta->frame_size = par->sample_rate * 256 / 245;
     avpriv_set_pts_info(s->streams[0], 64, 1, par->sample_rate);
 
     return 0;
 }
 
 static int tta_write_header(AVFormatContext *s)
 {
     TTAMuxContext *tta = s->priv_data;
     AVCodecParameters *par = s->streams[0]->codecpar;
     int ret;
 

     if ((ret = avio_open_dyn_buf(&tta->seek_table)) < 0)
         return ret;
 
     /* Ignore most extradata information if present. It can be innacurate
        if for example remuxing from Matroska */
     ffio_init_checksum(s->pb, ff_crcEDB88320_update, UINT32_MAX);
     ffio_init_checksum(tta->seek_table, ff_crcEDB88320_update, UINT32_MAX);
     avio_write(s->pb, "TTA1", 4);
     avio_wl16(s->pb, par->extradata ? AV_RL16(par->extradata + 4) : 1);
     avio_wl16(s->pb, par->channels);
     avio_wl16(s->pb, par->bits_per_raw_sample);
     avio_wl32(s->pb, par->sample_rate);
 
     return 0;
 }
 
 static int tta_write_packet(AVFormatContext *s, AVPacket *pkt)
 {
     TTAMuxContext *tta = s->priv_data;

     AVPacketList *pktl = av_mallocz(sizeof(*pktl));
     int ret;
 
     if (!pktl)
         return AVERROR(ENOMEM);
 
     ret = av_packet_ref(&pktl->pkt, pkt);
     if (ret < 0) {
         av_free(pktl);
         return ret;
     }
     if (tta->queue_end)
         tta->queue_end->next = pktl;
     else
         tta->queue = pktl;
     tta->queue_end = pktl;

 
     avio_wl32(tta->seek_table, pkt->size);
     tta->nb_samples += pkt->duration;
 
     if (tta->frame_size != pkt->duration) {
         if (tta->last_frame) {
             /* Two frames with a different duration than the default frame
                size means the TTA stream comes from a faulty container, and
                there's no way the last frame duration will be correct. */
             av_log(s, AV_LOG_ERROR, "Invalid frame durations\n");
 
             return AVERROR_INVALIDDATA;
         }
         /* First frame with a different duration than the default frame size.
            Assume it's the last frame in the stream and continue. */
         tta->last_frame++;
     }
 
     return 0;
 }
 

 static void tta_queue_flush(AVFormatContext *s)
 {
     TTAMuxContext *tta = s->priv_data;
     AVPacketList *pktl;
 
     while (pktl = tta->queue) {
         AVPacket *pkt = &pktl->pkt;
         avio_write(s->pb, pkt->data, pkt->size);
         av_packet_unref(pkt);
         tta->queue = pktl->next;
         av_free(pktl);
     }
     tta->queue_end = NULL;
 }
 

 static int tta_write_trailer(AVFormatContext *s)
 {
     TTAMuxContext *tta = s->priv_data;
     uint8_t *ptr;
     unsigned int crc;
     int size;
 
     avio_wl32(s->pb, tta->nb_samples);
     crc = ffio_get_checksum(s->pb) ^ UINT32_MAX;
     avio_wl32(s->pb, crc);
 
     /* Write Seek table */
     crc = ffio_get_checksum(tta->seek_table) ^ UINT32_MAX;
     avio_wl32(tta->seek_table, crc);
     size = avio_close_dyn_buf(tta->seek_table, &ptr);
     avio_write(s->pb, ptr, size);
     av_free(ptr);
 
     /* Write audio data */

     tta_queue_flush(s);

 
     ff_ape_write_tag(s);
     avio_flush(s->pb);
 
     return 0;
 }
 
 AVOutputFormat ff_tta_muxer = {
     .name              = "tta",
     .long_name         = NULL_IF_CONFIG_SMALL("TTA (True Audio)"),
     .mime_type         = "audio/x-tta",
     .extensions        = "tta",
     .priv_data_size    = sizeof(TTAMuxContext),
     .audio_codec       = AV_CODEC_ID_TTA,
     .video_codec       = AV_CODEC_ID_NONE,

     .init              = tta_init,

     .write_header      = tta_write_header,
     .write_packet      = tta_write_packet,
     .write_trailer     = tta_write_trailer,
 };