/*
  * Chromaprint fingerprinting muxer
  * Copyright (c) 2015 Rodger Combs
  *
  * 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 "avformat.h"
 #include "libavutil/opt.h"
 #include "libavcodec/internal.h"
 #include <chromaprint.h>
 
 #define CPR_VERSION_INT AV_VERSION_INT(CHROMAPRINT_VERSION_MAJOR, \
                                        CHROMAPRINT_VERSION_MINOR, \
                                        CHROMAPRINT_VERSION_PATCH)
 
 typedef enum FingerprintFormat {
     FINGERPRINT_RAW,
     FINGERPRINT_COMPRESSED,
     FINGERPRINT_BASE64,
 } FingerprintFormat;
 
 typedef struct ChromaprintMuxContext {
     const AVClass *class;
     int silence_threshold;
     int algorithm;
     FingerprintFormat fp_format;

 #if CPR_VERSION_INT >= AV_VERSION_INT(1, 4, 0)
     ChromaprintContext *ctx;
 #else

     ChromaprintContext ctx;

 #endif

 } ChromaprintMuxContext;
 
 static void cleanup(ChromaprintMuxContext *cpr)
 {
     if (cpr->ctx) {
         avpriv_lock_avformat();
         chromaprint_free(cpr->ctx);
         avpriv_unlock_avformat();
     }
 }
 
 static int write_header(AVFormatContext *s)
 {
     ChromaprintMuxContext *cpr = s->priv_data;
     AVStream *st;
 
     avpriv_lock_avformat();
     cpr->ctx = chromaprint_new(cpr->algorithm);
     avpriv_unlock_avformat();
 
     if (!cpr->ctx) {
         av_log(s, AV_LOG_ERROR, "Failed to create chromaprint context.\n");
         return AVERROR(ENOMEM);
     }
 
     if (cpr->silence_threshold != -1) {
 #if CPR_VERSION_INT >= AV_VERSION_INT(0, 7, 0)
         if (!chromaprint_set_option(cpr->ctx, "silence_threshold", cpr->silence_threshold)) {
             av_log(s, AV_LOG_ERROR, "Failed to set silence threshold.\n");
             goto fail;
         }
 #else
         av_log(s, AV_LOG_ERROR, "Setting the silence threshold requires Chromaprint "
                                 "version 0.7.0 or later.\n");
         goto fail;
 #endif
     }
 
     if (s->nb_streams != 1) {
         av_log(s, AV_LOG_ERROR, "Only one stream is supported\n");
         goto fail;
     }
 
     st = s->streams[0];
 

     if (st->codecpar->channels > 2) {

         av_log(s, AV_LOG_ERROR, "Only up to 2 channels are supported\n");
         goto fail;
     }
 

     if (st->codecpar->sample_rate < 1000) {

         av_log(s, AV_LOG_ERROR, "Sampling rate must be at least 1000\n");
         goto fail;
     }
 

     if (!chromaprint_start(cpr->ctx, st->codecpar->sample_rate, st->codecpar->channels)) {

         av_log(s, AV_LOG_ERROR, "Failed to start chromaprint\n");
         goto fail;
     }
 
     return 0;
 fail:
     cleanup(cpr);
     return AVERROR(EINVAL);
 }
 
 static int write_packet(AVFormatContext *s, AVPacket *pkt)
 {
     ChromaprintMuxContext *cpr = s->priv_data;
     return chromaprint_feed(cpr->ctx, pkt->data, pkt->size / 2) ? 0 : AVERROR(EINVAL);
 }
 
 static int write_trailer(AVFormatContext *s)
 {
     ChromaprintMuxContext *cpr = s->priv_data;
     AVIOContext *pb = s->pb;
     void *fp = NULL, *enc_fp = NULL;
     int size, enc_size, ret = AVERROR(EINVAL);
 
     if (!chromaprint_finish(cpr->ctx)) {
         av_log(s, AV_LOG_ERROR, "Failed to generate fingerprint\n");
         goto fail;
     }
 
     if (!chromaprint_get_raw_fingerprint(cpr->ctx, &fp, &size)) {
         av_log(s, AV_LOG_ERROR, "Failed to retrieve fingerprint\n");
         goto fail;
     }
 
     switch (cpr->fp_format) {
     case FINGERPRINT_RAW:
         avio_write(pb, fp, size);
         break;
     case FINGERPRINT_COMPRESSED:
     case FINGERPRINT_BASE64:
         if (!chromaprint_encode_fingerprint(fp, size, cpr->algorithm, &enc_fp, &enc_size,
                                             cpr->fp_format == FINGERPRINT_BASE64)) {
             av_log(s, AV_LOG_ERROR, "Failed to encode fingerprint\n");
             goto fail;
         }
         avio_write(pb, enc_fp, enc_size);
         break;
     }
 
     ret = 0;
 fail:
     if (fp)
         chromaprint_dealloc(fp);
     if (enc_fp)
         chromaprint_dealloc(enc_fp);
     cleanup(cpr);
     return ret;
 }
 
 #define OFFSET(x) offsetof(ChromaprintMuxContext, x)
 #define FLAGS AV_OPT_FLAG_ENCODING_PARAM
 static const AVOption options[] = {
     { "silence_threshold", "threshold for detecting silence", OFFSET(silence_threshold), AV_OPT_TYPE_INT, { .i64 = -1 }, -1, 32767, FLAGS },
     { "algorithm", "version of the fingerprint algorithm", OFFSET(algorithm), AV_OPT_TYPE_INT, { .i64 = CHROMAPRINT_ALGORITHM_DEFAULT }, CHROMAPRINT_ALGORITHM_TEST1, INT_MAX, FLAGS },
     { "fp_format", "fingerprint format to write", OFFSET(fp_format), AV_OPT_TYPE_INT, { .i64 = FINGERPRINT_BASE64 }, FINGERPRINT_RAW, FINGERPRINT_BASE64, FLAGS },
     { "raw", "binary raw fingerprint", 0, AV_OPT_TYPE_CONST, {.i64 = FINGERPRINT_RAW }, INT_MIN, INT_MAX, FLAGS, "fp_format"},
     { "compressed", "binary compressed fingerprint", 0, AV_OPT_TYPE_CONST, {.i64 = FINGERPRINT_COMPRESSED }, INT_MIN, INT_MAX, FLAGS, "fp_format"},
     { "base64", "Base64 compressed fingerprint", 0, AV_OPT_TYPE_CONST, {.i64 = FINGERPRINT_BASE64 }, INT_MIN, INT_MAX, FLAGS, "fp_format"},
     { NULL },
 };
 
 static const AVClass chromaprint_class = {
     .class_name = "chromaprint muxer",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
 AVOutputFormat ff_chromaprint_muxer = {
     .name              = "chromaprint",
     .long_name         = NULL_IF_CONFIG_SMALL("Chromaprint"),
     .priv_data_size    = sizeof(ChromaprintMuxContext),
     .audio_codec       = AV_NE(AV_CODEC_ID_PCM_S16BE, AV_CODEC_ID_PCM_S16LE),
     .write_header      = write_header,
     .write_packet      = write_packet,
     .write_trailer     = write_trailer,
     .flags             = AVFMT_NOTIMESTAMPS,
     .priv_class        = &chromaprint_class,
 };