/*
  * WavPack demuxer

  * Copyright (c) 2006 Konstantin Shishkov

  *

  * 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/intreadwrite.h"

 #include "avformat.h"
 
 // specs say that maximum block size is 1Mb
 #define WV_BLOCK_LIMIT 1047576
 
 #define WV_EXTRA_SIZE 12
 
 enum WV_FLAGS{
     WV_MONO   = 0x0004,
     WV_HYBRID = 0x0008,
     WV_JOINT  = 0x0010,
     WV_CROSSD = 0x0020,
     WV_HSHAPE = 0x0040,
     WV_FLOAT  = 0x0080,
     WV_INT32  = 0x0100,
     WV_HBR    = 0x0200,
     WV_HBAL   = 0x0400,
     WV_MCINIT = 0x0800,
     WV_MCEND  = 0x1000,
 };
 
 static const int wv_rates[16] = {
      6000,  8000,  9600, 11025, 12000, 16000, 22050, 24000,
     32000, 44100, 48000, 64000, 88200, 96000, 192000, -1
 };
 
 typedef struct{
     uint32_t blksize, flags;
     int rate, chan, bpp;

     uint32_t samples, soff;

     int block_parsed;
     uint8_t extra[WV_EXTRA_SIZE];

     int64_t pos;

 }WVContext;
 
 static int wv_probe(AVProbeData *p)
 {
     /* check file header */
     if (p->buf_size <= 32)
         return 0;
     if (p->buf[0] == 'w' && p->buf[1] == 'v' &&
         p->buf[2] == 'p' && p->buf[3] == 'k')
         return AVPROBE_SCORE_MAX;
     else
         return 0;
 }
 
 static int wv_read_block_header(AVFormatContext *ctx, ByteIOContext *pb)
 {
     WVContext *wc = ctx->priv_data;
     uint32_t tag, ver;
     int size;
     int rate, bpp, chan;
 

     wc->pos = url_ftell(pb);

     tag = get_le32(pb);
     if (tag != MKTAG('w', 'v', 'p', 'k'))
         return -1;
     size = get_le32(pb);
     if(size < 24 || size > WV_BLOCK_LIMIT){
         av_log(ctx, AV_LOG_ERROR, "Incorrect block size %i\n", size);
         return -1;
     }
     wc->blksize = size;
     ver = get_le16(pb);

     if(ver < 0x402 || ver > 0x410){

         av_log(ctx, AV_LOG_ERROR, "Unsupported version %03X\n", ver);
         return -1;
     }
     get_byte(pb); // track no
     get_byte(pb); // track sub index

     wc->samples = get_le32(pb); // total samples in file
     wc->soff = get_le32(pb); // offset in samples of current block

     get_buffer(pb, wc->extra, WV_EXTRA_SIZE);

     wc->flags = AV_RL32(wc->extra + 4);

     //parse flags
     if(wc->flags & WV_FLOAT){
         av_log(ctx, AV_LOG_ERROR, "Floating point data is not supported\n");
         return -1;
     }
 
     bpp = ((wc->flags & 3) + 1) << 3;
     chan = 1 + !(wc->flags & WV_MONO);
     rate = wv_rates[(wc->flags >> 23) & 0xF];
     if(rate == -1){
         av_log(ctx, AV_LOG_ERROR, "Unknown sampling rate\n");
         return -1;
     }
     if(!wc->bpp) wc->bpp = bpp;
     if(!wc->chan) wc->chan = chan;
     if(!wc->rate) wc->rate = rate;
 

     if(wc->flags && bpp != wc->bpp){

         av_log(ctx, AV_LOG_ERROR, "Bits per sample differ, this block: %i, header block: %i\n", bpp, wc->bpp);
         return -1;
     }

     if(wc->flags && chan != wc->chan){

         av_log(ctx, AV_LOG_ERROR, "Channels differ, this block: %i, header block: %i\n", chan, wc->chan);
         return -1;
     }

     if(wc->flags && rate != wc->rate){

         av_log(ctx, AV_LOG_ERROR, "Sampling rate differ, this block: %i, header block: %i\n", rate, wc->rate);
         return -1;
     }
     wc->blksize = size - 24;
     return 0;
 }
 
 static int wv_read_header(AVFormatContext *s,
                           AVFormatParameters *ap)
 {

     ByteIOContext *pb = s->pb;

     WVContext *wc = s->priv_data;
     AVStream *st;
 
     if(wv_read_block_header(s, pb) < 0)
         return -1;
 
     wc->block_parsed = 0;
     /* now we are ready: build format streams */
     st = av_new_stream(s, 0);
     if (!st)
         return -1;
     st->codec->codec_type = CODEC_TYPE_AUDIO;
     st->codec->codec_id = CODEC_ID_WAVPACK;
     st->codec->channels = wc->chan;
     st->codec->sample_rate = wc->rate;

     st->codec->bits_per_coded_sample = wc->bpp;

     av_set_pts_info(st, 64, 1, wc->rate);

     s->start_time = 0;
     s->duration = (int64_t)wc->samples * AV_TIME_BASE / st->codec->sample_rate;

     return 0;
 }
 
 static int wv_read_packet(AVFormatContext *s,
                           AVPacket *pkt)
 {
     WVContext *wc = s->priv_data;

     int ret;

     if (url_feof(s->pb))

         return AVERROR(EIO);

     if(wc->block_parsed){

         if(wv_read_block_header(s, s->pb) < 0)

             return -1;
     }
 
     if(av_new_packet(pkt, wc->blksize + WV_EXTRA_SIZE) < 0)

         return AVERROR(ENOMEM);

     memcpy(pkt->data, wc->extra, WV_EXTRA_SIZE);

     ret = get_buffer(s->pb, pkt->data + WV_EXTRA_SIZE, wc->blksize);

     if(ret != wc->blksize){
         av_free_packet(pkt);

         return AVERROR(EIO);

     }
     pkt->stream_index = 0;
     wc->block_parsed = 1;
     pkt->size = ret + WV_EXTRA_SIZE;

     pkt->pts = wc->soff;
     av_add_index_entry(s->streams[0], wc->pos, pkt->pts, 0, 0, AVINDEX_KEYFRAME);

     return 0;
 }
 

 static int wv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
 {
     AVStream *st = s->streams[stream_index];
     WVContext *wc = s->priv_data;
     AVPacket pkt1, *pkt = &pkt1;
     int ret;
     int index = av_index_search_timestamp(st, timestamp, flags);
     int64_t pos, pts;
 
     /* if found, seek there */
     if (index >= 0){
         wc->block_parsed = 1;

         url_fseek(s->pb, st->index_entries[index].pos, SEEK_SET);

         return 0;
     }
     /* if timestamp is out of bounds, return error */
     if(timestamp < 0 || timestamp >= s->duration)
         return -1;
 

     pos = url_ftell(s->pb);

     do{
         ret = av_read_frame(s, pkt);
         if (ret < 0){

             url_fseek(s->pb, pos, SEEK_SET);

             return -1;
         }
         pts = pkt->pts;
         av_free_packet(pkt);
     }while(pts < timestamp);
     return 0;
 }
 

 AVInputFormat wv_demuxer = {
     "wv",

     NULL_IF_CONFIG_SMALL("WavPack"),

     sizeof(WVContext),
     wv_probe,
     wv_read_header,
     wv_read_packet,

     NULL,

     wv_read_seek,

 };