/*
  * Copyright (C) 2016 foo86
  *
  * 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/opt.h"
 #include "libavutil/channel_layout.h"
 
 #include "dcadec.h"

 #include "dcahuff.h"

 #include "dca_syncwords.h"
 #include "profiles.h"
 
 #define MIN_PACKET_SIZE     16
 #define MAX_PACKET_SIZE     0x104000
 
 int ff_dca_set_channel_layout(AVCodecContext *avctx, int *ch_remap, int dca_mask)
 {
     static const uint8_t dca2wav_norm[28] = {
          2,  0, 1, 9, 10,  3,  8,  4,  5,  9, 10, 6, 7, 12,
         13, 14, 3, 6,  7, 11, 12, 14, 16, 15, 17, 8, 4,  5,
     };
 
     static const uint8_t dca2wav_wide[28] = {
          2,  0, 1, 4,  5,  3,  8,  4,  5,  9, 10, 6, 7, 12,
         13, 14, 3, 9, 10, 11, 12, 14, 16, 15, 17, 8, 4,  5,
     };
 
     int dca_ch, wav_ch, nchannels = 0;
 
     if (avctx->request_channel_layout & AV_CH_LAYOUT_NATIVE) {
         for (dca_ch = 0; dca_ch < DCA_SPEAKER_COUNT; dca_ch++)
             if (dca_mask & (1U << dca_ch))
                 ch_remap[nchannels++] = dca_ch;
         avctx->channel_layout = dca_mask;
     } else {
         int wav_mask = 0;
         int wav_map[18];
         const uint8_t *dca2wav;
         if (dca_mask == DCA_SPEAKER_LAYOUT_7POINT0_WIDE ||
             dca_mask == DCA_SPEAKER_LAYOUT_7POINT1_WIDE)
             dca2wav = dca2wav_wide;
         else
             dca2wav = dca2wav_norm;
         for (dca_ch = 0; dca_ch < 28; dca_ch++) {
             if (dca_mask & (1 << dca_ch)) {
                 wav_ch = dca2wav[dca_ch];
                 if (!(wav_mask & (1 << wav_ch))) {
                     wav_map[wav_ch] = dca_ch;
                     wav_mask |= 1 << wav_ch;
                 }
             }
         }
         for (wav_ch = 0; wav_ch < 18; wav_ch++)
             if (wav_mask & (1 << wav_ch))
                 ch_remap[nchannels++] = wav_map[wav_ch];
         avctx->channel_layout = wav_mask;
     }
 
     avctx->channels = nchannels;
     return nchannels;
 }
 
 void ff_dca_downmix_to_stereo_fixed(DCADSPContext *dcadsp, int32_t **samples,
                                     int *coeff_l, int nsamples, int ch_mask)
 {
     int pos, spkr, max_spkr = av_log2(ch_mask);
     int *coeff_r = coeff_l + av_popcount(ch_mask);
 
     av_assert0(DCA_HAS_STEREO(ch_mask));
 
     // Scale left and right channels
     pos = (ch_mask & DCA_SPEAKER_MASK_C);
     dcadsp->dmix_scale(samples[DCA_SPEAKER_L], coeff_l[pos    ], nsamples);
     dcadsp->dmix_scale(samples[DCA_SPEAKER_R], coeff_r[pos + 1], nsamples);
 
     // Downmix remaining channels
     for (spkr = 0; spkr <= max_spkr; spkr++) {
         if (!(ch_mask & (1U << spkr)))
             continue;
 
         if (*coeff_l && spkr != DCA_SPEAKER_L)
             dcadsp->dmix_add(samples[DCA_SPEAKER_L], samples[spkr],
                              *coeff_l, nsamples);
 
         if (*coeff_r && spkr != DCA_SPEAKER_R)
             dcadsp->dmix_add(samples[DCA_SPEAKER_R], samples[spkr],
                              *coeff_r, nsamples);
 
         coeff_l++;
         coeff_r++;
     }
 }
 
 void ff_dca_downmix_to_stereo_float(AVFloatDSPContext *fdsp, float **samples,
                                     int *coeff_l, int nsamples, int ch_mask)
 {
     int pos, spkr, max_spkr = av_log2(ch_mask);
     int *coeff_r = coeff_l + av_popcount(ch_mask);
     const float scale = 1.0f / (1 << 15);
 
     av_assert0(DCA_HAS_STEREO(ch_mask));
 
     // Scale left and right channels
     pos = (ch_mask & DCA_SPEAKER_MASK_C);
     fdsp->vector_fmul_scalar(samples[DCA_SPEAKER_L], samples[DCA_SPEAKER_L],
                              coeff_l[pos    ] * scale, nsamples);
     fdsp->vector_fmul_scalar(samples[DCA_SPEAKER_R], samples[DCA_SPEAKER_R],
                              coeff_r[pos + 1] * scale, nsamples);
 
     // Downmix remaining channels
     for (spkr = 0; spkr <= max_spkr; spkr++) {
         if (!(ch_mask & (1U << spkr)))
             continue;
 
         if (*coeff_l && spkr != DCA_SPEAKER_L)
             fdsp->vector_fmac_scalar(samples[DCA_SPEAKER_L], samples[spkr],
                                      *coeff_l * scale, nsamples);
 
         if (*coeff_r && spkr != DCA_SPEAKER_R)
             fdsp->vector_fmac_scalar(samples[DCA_SPEAKER_R], samples[spkr],
                                      *coeff_r * scale, nsamples);
 
         coeff_l++;
         coeff_r++;
     }
 }
 
 static int dcadec_decode_frame(AVCodecContext *avctx, void *data,
                                int *got_frame_ptr, AVPacket *avpkt)
 {
     DCAContext *s = avctx->priv_data;
     AVFrame *frame = data;
     uint8_t *input = avpkt->data;
     int input_size = avpkt->size;
     int i, ret, prev_packet = s->packet;

     uint32_t mrk;

 
     if (input_size < MIN_PACKET_SIZE || input_size > MAX_PACKET_SIZE) {
         av_log(avctx, AV_LOG_ERROR, "Invalid packet size\n");
         return AVERROR_INVALIDDATA;
     }
 

     // Convert input to BE format
     mrk = AV_RB32(input);
     if (mrk != DCA_SYNCWORD_CORE_BE && mrk != DCA_SYNCWORD_SUBSTREAM) {
         av_fast_padded_malloc(&s->buffer, &s->buffer_size, input_size);
         if (!s->buffer)
             return AVERROR(ENOMEM);

         for (i = 0, ret = AVERROR_INVALIDDATA; i < input_size - MIN_PACKET_SIZE + 1 && ret < 0; i++)
             ret = avpriv_dca_convert_bitstream(input + i, input_size - i, s->buffer, s->buffer_size);

         if (ret < 0) {
             av_log(avctx, AV_LOG_ERROR, "Not a valid DCA frame\n");
             return ret;
         }

         input      = s->buffer;
         input_size = ret;
     }

 
     s->packet = 0;
 
     // Parse backward compatible core sub-stream
     if (AV_RB32(input) == DCA_SYNCWORD_CORE_BE) {
         int frame_size;
 

         if ((ret = ff_dca_core_parse(&s->core, input, input_size)) < 0)

             return ret;
 
         s->packet |= DCA_PACKET_CORE;
 
         // EXXS data must be aligned on 4-byte boundary
         frame_size = FFALIGN(s->core.frame_size, 4);
         if (input_size - 4 > frame_size) {
             input      += frame_size;
             input_size -= frame_size;
         }
     }
 
     if (!s->core_only) {
         DCAExssAsset *asset = NULL;
 
         // Parse extension sub-stream (EXSS)
         if (AV_RB32(input) == DCA_SYNCWORD_SUBSTREAM) {
             if ((ret = ff_dca_exss_parse(&s->exss, input, input_size)) < 0) {
                 if (avctx->err_recognition & AV_EF_EXPLODE)
                     return ret;
             } else {
                 s->packet |= DCA_PACKET_EXSS;
                 asset = &s->exss.assets[0];
             }
         }
 
         // Parse XLL component in EXSS
         if (asset && (asset->extension_mask & DCA_EXSS_XLL)) {
             if ((ret = ff_dca_xll_parse(&s->xll, input, asset)) < 0) {
                 // Conceal XLL synchronization error
                 if (ret == AVERROR(EAGAIN)
                     && (prev_packet & DCA_PACKET_XLL)
                     && (s->packet & DCA_PACKET_CORE))
                     s->packet |= DCA_PACKET_XLL | DCA_PACKET_RECOVERY;
                 else if (ret == AVERROR(ENOMEM) || (avctx->err_recognition & AV_EF_EXPLODE))
                     return ret;
             } else {
                 s->packet |= DCA_PACKET_XLL;
             }
         }
 

         // Parse LBR component in EXSS
         if (asset && (asset->extension_mask & DCA_EXSS_LBR)) {
             if ((ret = ff_dca_lbr_parse(&s->lbr, input, asset)) < 0) {
                 if (ret == AVERROR(ENOMEM) || (avctx->err_recognition & AV_EF_EXPLODE))
                     return ret;
             } else {
                 s->packet |= DCA_PACKET_LBR;
             }
         }
 

         // Parse core extensions in EXSS or backward compatible core sub-stream
         if ((s->packet & DCA_PACKET_CORE)
             && (ret = ff_dca_core_parse_exss(&s->core, input, asset)) < 0)
             return ret;
     }
 
     // Filter the frame

     if (s->packet & DCA_PACKET_LBR) {
         if ((ret = ff_dca_lbr_filter_frame(&s->lbr, frame)) < 0)
             return ret;
     } else if (s->packet & DCA_PACKET_XLL) {

         if (s->packet & DCA_PACKET_CORE) {
             int x96_synth = -1;
 
             // Enable X96 synthesis if needed
             if (s->xll.chset[0].freq == 96000 && s->core.sample_rate == 48000)
                 x96_synth = 1;
 

             if ((ret = ff_dca_core_filter_fixed(&s->core, x96_synth)) < 0)

                 return ret;
 
             // Force lossy downmixed output on the first core frame filtered.
             // This prevents audible clicks when seeking and is consistent with
             // what reference decoder does when there are multiple channel sets.

             if (!(prev_packet & DCA_PACKET_RESIDUAL) && s->xll.nreschsets > 0
                 && s->xll.nchsets > 1) {
                 av_log(avctx, AV_LOG_VERBOSE, "Forcing XLL recovery mode\n");
                 s->packet |= DCA_PACKET_RECOVERY;

             }

 
             // Set 'residual ok' flag for the next frame
             s->packet |= DCA_PACKET_RESIDUAL;

         }
 
         if ((ret = ff_dca_xll_filter_frame(&s->xll, frame)) < 0) {
             // Fall back to core unless hard error
             if (!(s->packet & DCA_PACKET_CORE))
                 return ret;
             if (ret != AVERROR_INVALIDDATA || (avctx->err_recognition & AV_EF_EXPLODE))
                 return ret;

             if ((ret = ff_dca_core_filter_frame(&s->core, frame)) < 0)

                 return ret;
         }
     } else if (s->packet & DCA_PACKET_CORE) {

         if ((ret = ff_dca_core_filter_frame(&s->core, frame)) < 0)

             return ret;

         if (s->core.filter_mode & DCA_FILTER_MODE_FIXED)
             s->packet |= DCA_PACKET_RESIDUAL;

     } else {

         av_log(avctx, AV_LOG_ERROR, "No valid DCA sub-stream found\n");
         if (s->core_only)
             av_log(avctx, AV_LOG_WARNING, "Consider disabling 'core_only' option\n");

         return AVERROR_INVALIDDATA;
     }
 
     *got_frame_ptr = 1;
 
     return avpkt->size;
 }
 
 static av_cold void dcadec_flush(AVCodecContext *avctx)
 {
     DCAContext *s = avctx->priv_data;
 
     ff_dca_core_flush(&s->core);
     ff_dca_xll_flush(&s->xll);

     ff_dca_lbr_flush(&s->lbr);

     s->packet &= DCA_PACKET_MASK;

 }
 
 static av_cold int dcadec_close(AVCodecContext *avctx)
 {
     DCAContext *s = avctx->priv_data;
 
     ff_dca_core_close(&s->core);
     ff_dca_xll_close(&s->xll);

     ff_dca_lbr_close(&s->lbr);

 
     av_freep(&s->buffer);
     s->buffer_size = 0;
 
     return 0;
 }
 
 static av_cold int dcadec_init(AVCodecContext *avctx)
 {
     DCAContext *s = avctx->priv_data;
 
     s->avctx = avctx;
     s->core.avctx = avctx;
     s->exss.avctx = avctx;
     s->xll.avctx = avctx;

     s->lbr.avctx = avctx;

     ff_dca_init_vlcs();
 

     if (ff_dca_core_init(&s->core) < 0)
         return AVERROR(ENOMEM);
 

     if (ff_dca_lbr_init(&s->lbr) < 0)
         return AVERROR(ENOMEM);
 

     ff_dcadsp_init(&s->dcadsp);
     s->core.dcadsp = &s->dcadsp;
     s->xll.dcadsp = &s->dcadsp;

     s->lbr.dcadsp = &s->dcadsp;

     s->crctab = av_crc_get_table(AV_CRC_16_CCITT);
 

     switch (avctx->request_channel_layout & ~AV_CH_LAYOUT_NATIVE) {
     case 0:
         s->request_channel_layout = 0;
         break;
     case AV_CH_LAYOUT_STEREO:
     case AV_CH_LAYOUT_STEREO_DOWNMIX:
         s->request_channel_layout = DCA_SPEAKER_LAYOUT_STEREO;
         break;
     case AV_CH_LAYOUT_5POINT0:
         s->request_channel_layout = DCA_SPEAKER_LAYOUT_5POINT0;
         break;
     case AV_CH_LAYOUT_5POINT1:
         s->request_channel_layout = DCA_SPEAKER_LAYOUT_5POINT1;
         break;
     default:
         av_log(avctx, AV_LOG_WARNING, "Invalid request_channel_layout\n");
         break;
     }
 
     return 0;
 }
 
 #define OFFSET(x) offsetof(DCAContext, x)
 #define PARAM AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_DECODING_PARAM
 
 static const AVOption dcadec_options[] = {
     { "core_only", "Decode core only without extensions", OFFSET(core_only), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, PARAM },
     { NULL }
 };
 
 static const AVClass dcadec_class = {
     .class_name = "DCA decoder",
     .item_name  = av_default_item_name,
     .option     = dcadec_options,
     .version    = LIBAVUTIL_VERSION_INT,
     .category   = AV_CLASS_CATEGORY_DECODER,
 };
 
 AVCodec ff_dca_decoder = {
     .name           = "dca",
     .long_name      = NULL_IF_CONFIG_SMALL("DCA (DTS Coherent Acoustics)"),
     .type           = AVMEDIA_TYPE_AUDIO,
     .id             = AV_CODEC_ID_DTS,
     .priv_data_size = sizeof(DCAContext),
     .init           = dcadec_init,
     .decode         = dcadec_decode_frame,
     .close          = dcadec_close,
     .flush          = dcadec_flush,
     .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_CHANNEL_CONF,
     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P, AV_SAMPLE_FMT_S32P,
                                                       AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_NONE },
     .priv_class     = &dcadec_class,
     .profiles       = NULL_IF_CONFIG_SMALL(ff_dca_profiles),
     .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,
 };