/*

  * 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 <stdint.h>
 
 #include "libavutil/common.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/log.h"
 #include "libavutil/opt.h"
 
 #include "avcodec.h"
 #include "bsf.h"
 #include "h2645_parse.h"
 #include "h264.h"
 #include "hevc.h"
 #include "vc1_common.h"
 
 typedef struct ExtractExtradataContext {
     const AVClass *class;
 
     int (*extract)(AVBSFContext *ctx, AVPacket *pkt,
                    uint8_t **data, int *size);
 

     /* H264/HEVC specifc fields */
     H2645Packet h2645_pkt;
 

     /* AVOptions */
     int remove;
 } ExtractExtradataContext;
 
 static int val_in_array(const int *arr, int len, int val)
 {
     int i;
     for (i = 0; i < len; i++)
         if (arr[i] == val)
             return 1;
     return 0;
 }
 
 static int extract_extradata_h2645(AVBSFContext *ctx, AVPacket *pkt,
                                    uint8_t **data, int *size)
 {
     static const int extradata_nal_types_hevc[] = {
         HEVC_NAL_VPS, HEVC_NAL_SPS, HEVC_NAL_PPS,
     };
     static const int extradata_nal_types_h264[] = {
         H264_NAL_SPS, H264_NAL_PPS,
     };
 
     ExtractExtradataContext *s = ctx->priv_data;
 

     int extradata_size = 0, filtered_size = 0;

     const int *extradata_nal_types;
     int nb_extradata_nal_types;

     int i, has_sps = 0, has_vps = 0, ret = 0;

 
     if (ctx->par_in->codec_id == AV_CODEC_ID_HEVC) {
         extradata_nal_types    = extradata_nal_types_hevc;
         nb_extradata_nal_types = FF_ARRAY_ELEMS(extradata_nal_types_hevc);
     } else {
         extradata_nal_types    = extradata_nal_types_h264;
         nb_extradata_nal_types = FF_ARRAY_ELEMS(extradata_nal_types_h264);
     }
 

     ret = ff_h2645_packet_split(&s->h2645_pkt, pkt->data, pkt->size,

                                 ctx, 0, 0, ctx->par_in->codec_id, 1);

     if (ret < 0)

         return ret;

     for (i = 0; i < s->h2645_pkt.nb_nals; i++) {
         H2645NAL *nal = &s->h2645_pkt.nals[i];

         if (val_in_array(extradata_nal_types, nb_extradata_nal_types, nal->type)) {

             extradata_size += nal->raw_size + 3;

             if (ctx->par_in->codec_id == AV_CODEC_ID_HEVC) {
                 if (nal->type == HEVC_NAL_SPS) has_sps = 1;
                 if (nal->type == HEVC_NAL_VPS) has_vps = 1;
             } else {
                 if (nal->type == H264_NAL_SPS) has_sps = 1;
             }

         } else if (s->remove) {
             filtered_size += nal->raw_size + 3;

         }

     }
 

     if (extradata_size &&
         ((ctx->par_in->codec_id == AV_CODEC_ID_HEVC && has_sps && has_vps) ||
          (ctx->par_in->codec_id == AV_CODEC_ID_H264 && has_sps))) {

         AVBufferRef *filtered_buf;
         uint8_t *extradata, *filtered_data;
 
         if (s->remove) {

             filtered_buf = av_buffer_alloc(filtered_size + AV_INPUT_BUFFER_PADDING_SIZE);

             if (!filtered_buf) {

                 return AVERROR(ENOMEM);

             }

             memset(filtered_buf->data + filtered_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
 

             filtered_data = filtered_buf->data;
         }
 
         extradata = av_malloc(extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
         if (!extradata) {
             av_buffer_unref(&filtered_buf);

             return AVERROR(ENOMEM);

         }

         memset(extradata + extradata_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);

 
         *data = extradata;
         *size = extradata_size;
 

         for (i = 0; i < s->h2645_pkt.nb_nals; i++) {
             H2645NAL *nal = &s->h2645_pkt.nals[i];

             if (val_in_array(extradata_nal_types, nb_extradata_nal_types,
                              nal->type)) {
                 AV_WB24(extradata, 1); // startcode
                 memcpy(extradata + 3, nal->raw_data, nal->raw_size);
                 extradata += 3 + nal->raw_size;
             } else if (s->remove) {
                 AV_WB24(filtered_data, 1); // startcode
                 memcpy(filtered_data + 3, nal->raw_data, nal->raw_size);
                 filtered_data += 3 + nal->raw_size;
             }
         }
 
         if (s->remove) {
             av_buffer_unref(&pkt->buf);
             pkt->buf  = filtered_buf;
             pkt->data = filtered_buf->data;

             pkt->size = filtered_size;

         }
     }
 

     return 0;

 }
 
 static int extract_extradata_vc1(AVBSFContext *ctx, AVPacket *pkt,
                                  uint8_t **data, int *size)
 {
     ExtractExtradataContext *s = ctx->priv_data;

     const uint8_t *ptr = pkt->data, *end = pkt->data + pkt->size;

     uint32_t state = UINT32_MAX;
     int has_extradata = 0, extradata_size = 0;
 

     while (ptr < end) {
         ptr = avpriv_find_start_code(ptr, end, &state);
         if (state == VC1_CODE_SEQHDR || state == VC1_CODE_ENTRYPOINT) {
             has_extradata = 1;

         } else if (has_extradata && IS_MARKER(state)) {

             extradata_size = ptr - 4 - pkt->data;

             break;
         }

     }
 
     if (extradata_size) {
         *data = av_malloc(extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
         if (!*data)
             return AVERROR(ENOMEM);
 
         memcpy(*data, pkt->data, extradata_size);

         memset(*data + extradata_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);

         *size = extradata_size;
 
         if (s->remove) {
             pkt->data += extradata_size;
             pkt->size -= extradata_size;
         }
     }
 
     return 0;
 }
 

 static int extract_extradata_mpeg12(AVBSFContext *ctx, AVPacket *pkt,

                                      uint8_t **data, int *size)
 {
     ExtractExtradataContext *s = ctx->priv_data;

     uint32_t state = UINT32_MAX;
     int i, found = 0;
 
     for (i = 0; i < pkt->size; i++) {
         state = (state << 8) | pkt->data[i];
         if (state == 0x1B3)
             found = 1;
         else if (found && state != 0x1B5 && state < 0x200 && state >= 0x100) {
             if (i > 3) {
                 *size = i - 3;
                 *data = av_malloc(*size + AV_INPUT_BUFFER_PADDING_SIZE);
                 if (!*data)
                     return AVERROR(ENOMEM);
 
                 memcpy(*data, pkt->data, *size);

                 memset(*data + *size, 0, AV_INPUT_BUFFER_PADDING_SIZE);

 
                 if (s->remove) {
                     pkt->data += *size;
                     pkt->size -= *size;
                 }
             }
             break;
         }
     }
     return 0;
 }
 
 static int extract_extradata_mpeg4(AVBSFContext *ctx, AVPacket *pkt,
                                    uint8_t **data, int *size)
 {
     ExtractExtradataContext *s = ctx->priv_data;

     const uint8_t *ptr = pkt->data, *end = pkt->data + pkt->size;

     uint32_t state = UINT32_MAX;
 

     while (ptr < end) {
         ptr = avpriv_find_start_code(ptr, end, &state);
         if (state == 0x1B3 || state == 0x1B6) {
             if (ptr - pkt->data > 4) {
                 *size = ptr - 4 - pkt->data;

                 *data = av_malloc(*size + AV_INPUT_BUFFER_PADDING_SIZE);
                 if (!*data)
                     return AVERROR(ENOMEM);
 
                 memcpy(*data, pkt->data, *size);

                 memset(*data + *size, 0, AV_INPUT_BUFFER_PADDING_SIZE);

 
                 if (s->remove) {
                     pkt->data += *size;
                     pkt->size -= *size;
                 }
             }
             break;
         }
     }
     return 0;
 }
 
 static const struct {
     enum AVCodecID id;
     int (*extract)(AVBSFContext *ctx, AVPacket *pkt,
                    uint8_t **data, int *size);
 } extract_tab[] = {

     { AV_CODEC_ID_CAVS,       extract_extradata_mpeg4   },

     { AV_CODEC_ID_H264,       extract_extradata_h2645   },
     { AV_CODEC_ID_HEVC,       extract_extradata_h2645   },

     { AV_CODEC_ID_MPEG1VIDEO, extract_extradata_mpeg12  },
     { AV_CODEC_ID_MPEG2VIDEO, extract_extradata_mpeg12  },
     { AV_CODEC_ID_MPEG4,      extract_extradata_mpeg4   },

     { AV_CODEC_ID_VC1,        extract_extradata_vc1     },
 };
 
 static int extract_extradata_init(AVBSFContext *ctx)
 {
     ExtractExtradataContext *s = ctx->priv_data;
     int i;
 
     for (i = 0; i < FF_ARRAY_ELEMS(extract_tab); i++) {
         if (extract_tab[i].id == ctx->par_in->codec_id) {
             s->extract = extract_tab[i].extract;
             break;
         }
     }
     if (!s->extract)
         return AVERROR_BUG;
 
     return 0;
 }
 

 static int extract_extradata_filter(AVBSFContext *ctx, AVPacket *pkt)

 {
     ExtractExtradataContext *s = ctx->priv_data;
     uint8_t *extradata = NULL;
     int extradata_size;
     int ret = 0;
 

     ret = ff_bsf_get_packet_ref(ctx, pkt);

     if (ret < 0)
         return ret;
 

     ret = s->extract(ctx, pkt, &extradata, &extradata_size);

     if (ret < 0)
         goto fail;
 
     if (extradata) {

         ret = av_packet_add_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA,

                                       extradata, extradata_size);
         if (ret < 0) {
             av_freep(&extradata);
             goto fail;
         }
     }
 

     return 0;

 
 fail:

     av_packet_unref(pkt);

     return ret;
 }
 

 static void extract_extradata_close(AVBSFContext *ctx)
 {
     ExtractExtradataContext *s = ctx->priv_data;
     ff_h2645_packet_uninit(&s->h2645_pkt);
 }
 

 static const enum AVCodecID codec_ids[] = {
     AV_CODEC_ID_CAVS,
     AV_CODEC_ID_H264,
     AV_CODEC_ID_HEVC,
     AV_CODEC_ID_MPEG1VIDEO,
     AV_CODEC_ID_MPEG2VIDEO,
     AV_CODEC_ID_MPEG4,
     AV_CODEC_ID_VC1,
     AV_CODEC_ID_NONE,
 };
 
 #define OFFSET(x) offsetof(ExtractExtradataContext, x)

 #define FLAGS (AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_BSF_PARAM)

 static const AVOption options[] = {
     { "remove", "remove the extradata from the bitstream", OFFSET(remove), AV_OPT_TYPE_INT,

         { .i64 = 0 }, 0, 1, FLAGS },

     { NULL },
 };
 
 static const AVClass extract_extradata_class = {
     .class_name = "extract_extradata",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
 const AVBitStreamFilter ff_extract_extradata_bsf = {
     .name           = "extract_extradata",
     .codec_ids      = codec_ids,
     .priv_data_size = sizeof(ExtractExtradataContext),
     .priv_class     = &extract_extradata_class,
     .init           = extract_extradata_init,
     .filter         = extract_extradata_filter,

     .close          = extract_extradata_close,

 };