/*
  * AMR Audio encoder stub
  * Copyright (c) 2003 the ffmpeg project
  *

  * 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 <vo-amrwbenc/enc_if.h>

 #include <stdio.h>
 #include <stdlib.h>

 #include "libavutil/avstring.h"

 #include "libavutil/internal.h"
 #include "libavutil/mem.h"

 #include "libavutil/opt.h"

 #include "avcodec.h"
 #include "internal.h"
 
 #define MAX_PACKET_SIZE  (1 + (477 + 7) / 8)

 
 typedef struct AMRWBContext {

     AVClass *av_class;

     void  *state;
     int    mode;

     int    last_bitrate;

     int    allow_dtx;
 } AMRWBContext;
 

 static const AVOption options[] = {

     { "dtx", "Allow DTX (generate comfort noise)", offsetof(AMRWBContext, allow_dtx), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM },

     { NULL }
 };
 

 static const AVClass amrwb_class = {

     "libvo_amrwbenc", av_default_item_name, options, LIBAVUTIL_VERSION_INT
 };
 

 static int get_wb_bitrate_mode(int bitrate, void *log_ctx)

 {
     /* make the correspondance between bitrate and mode */

     static const int rates[] = {  6600,  8850, 12650, 14250, 15850, 18250,
                                  19850, 23050, 23850 };

     int i, best = -1, min_diff = 0;
     char log_buf[200];

     for (i = 0; i < 9; i++) {

         if (rates[i] == bitrate)
             return i;

         if (best < 0 || abs(rates[i] - bitrate) < min_diff) {
             best     = i;
             min_diff = abs(rates[i] - bitrate);
         }
     }
     /* no bitrate matching exactly, log a warning */
     snprintf(log_buf, sizeof(log_buf), "bitrate not supported: use one of ");
     for (i = 0; i < 9; i++)
         av_strlcatf(log_buf, sizeof(log_buf), "%.2fk, ", rates[i]    / 1000.f);
     av_strlcatf(log_buf, sizeof(log_buf), "using %.2fk", rates[best] / 1000.f);
     av_log(log_ctx, AV_LOG_WARNING, "%s\n", log_buf);
 
     return best;

 }
 
 static av_cold int amr_wb_encode_init(AVCodecContext *avctx)
 {
     AMRWBContext *s = avctx->priv_data;
 

     if (avctx->sample_rate != 16000 && avctx->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL) {

         av_log(avctx, AV_LOG_ERROR, "Only 16000Hz sample rate supported\n");

         return AVERROR(ENOSYS);

     }
 
     if (avctx->channels != 1) {
         av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");

         return AVERROR(ENOSYS);

     }
 

     s->mode            = get_wb_bitrate_mode(avctx->bit_rate, avctx);
     s->last_bitrate    = avctx->bit_rate;

 
     avctx->frame_size  = 320;

     avctx->delay       =  80;

 
     s->state     = E_IF_init();
 
     return 0;
 }
 
 static int amr_wb_encode_close(AVCodecContext *avctx)
 {
     AMRWBContext *s = avctx->priv_data;
 
     E_IF_exit(s->state);
     return 0;
 }
 

 static int amr_wb_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
                                const AVFrame *frame, int *got_packet_ptr)

 {
     AMRWBContext *s = avctx->priv_data;

     const int16_t *samples = (const int16_t *)frame->data[0];
     int size, ret;
 

     if ((ret = ff_alloc_packet2(avctx, avpkt, MAX_PACKET_SIZE)) < 0)

         return ret;

     if (s->last_bitrate != avctx->bit_rate) {
         s->mode         = get_wb_bitrate_mode(avctx->bit_rate, avctx);
         s->last_bitrate = avctx->bit_rate;
     }

     size = E_IF_encode(s->state, s->mode, samples, avpkt->data, s->allow_dtx);
     if (size <= 0 || size > MAX_PACKET_SIZE) {
         av_log(avctx, AV_LOG_ERROR, "Error encoding frame\n");
         return AVERROR(EINVAL);
     }
 
     if (frame->pts != AV_NOPTS_VALUE)
         avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->delay);
 
     avpkt->size = size;
     *got_packet_ptr = 1;
     return 0;

 }
 
 AVCodec ff_libvo_amrwbenc_encoder = {

     .name           = "libvo_amrwbenc",

     .long_name      = NULL_IF_CONFIG_SMALL("Android VisualOn AMR-WB "
                                            "(Adaptive Multi-Rate Wide-Band)"),

     .type           = AVMEDIA_TYPE_AUDIO,

     .id             = AV_CODEC_ID_AMR_WB,

     .priv_data_size = sizeof(AMRWBContext),
     .init           = amr_wb_encode_init,

     .encode2        = amr_wb_encode_frame,

     .close          = amr_wb_encode_close,

     .sample_fmts    = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
                                                      AV_SAMPLE_FMT_NONE },

     .priv_class     = &amrwb_class,

 };