/*

 * 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/log.h"

#include "libavutil/mem.h"

#include "libavutil/opt.h"

#include "av1.h"

#include "av1_parse.h"

#include "bsf.h"

#include "bsf_internal.h"

#include "bytestream.h"

#include "h2645_parse.h"

#include "h264.h"

#include "startcode.h"

#include "vc1_common.h"

#include "vvc.h"

#include "hevc/hevc.h"

typedef struct ExtractExtradataContext {

    const AVClass *class;

    int (*extract)(AVBSFContext *ctx, AVPacket *pkt,

                   uint8_t **data, int *size);

    /* AV1 specific fields */

    AV1Packet av1_pkt;

    /* H264/HEVC specific fields */

    H2645Packet h2645_pkt;

    /* AVOptions */

    int remove;

} ExtractExtradataContext;

static int val_in_array(const int *arr, size_t len, int val)

{

    for (size_t i = 0; i < len; i++)

        if (arr[i] == val)

            return 1;

    return 0;

}

static int metadata_is_global(const AV1OBU *obu)

{

    static const int metadata_obu_types[] = {

        AV1_METADATA_TYPE_HDR_CLL, AV1_METADATA_TYPE_HDR_MDCV,

    };

    GetBitContext gb;

    int metadata_type;

    if (init_get_bits(&gb, obu->data, obu->size_bits) < 0)

        return 0;

    metadata_type = get_leb(&gb);

    return val_in_array(metadata_obu_types, FF_ARRAY_ELEMS(metadata_obu_types),

                        metadata_type);

}

static int obu_is_global(const AV1OBU *obu)

{

    static const int extradata_obu_types[] = {

        AV1_OBU_SEQUENCE_HEADER, AV1_OBU_METADATA,

    };

    if (!val_in_array(extradata_obu_types, FF_ARRAY_ELEMS(extradata_obu_types),

                      obu->type))

        return 0;

    if (obu->type != AV1_OBU_METADATA)

        return 1;

    return metadata_is_global(obu);

}

static int extract_extradata_av1(AVBSFContext *ctx, AVPacket *pkt,

                                 uint8_t **data, int *size)

{

    ExtractExtradataContext *s = ctx->priv_data;

    int extradata_size = 0, filtered_size = 0;

    int i, has_seq = 0, ret = 0;

    ret = ff_av1_packet_split(&s->av1_pkt, pkt->data, pkt->size, ctx);

    if (ret < 0)

        return ret;

    for (i = 0; i < s->av1_pkt.nb_obus; i++) {

        AV1OBU *obu = &s->av1_pkt.obus[i];

        if (obu_is_global(obu)) {

            extradata_size += obu->raw_size;

            if (obu->type == AV1_OBU_SEQUENCE_HEADER)

                has_seq = 1;

        } else if (s->remove) {

            filtered_size += obu->raw_size;

        }

    }

    if (extradata_size && has_seq) {

        AVBufferRef *filtered_buf = NULL;

        PutByteContext pb_filtered_data, pb_extradata;

        uint8_t *extradata;

        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);

        }

        extradata = av_malloc(extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);

        if (!extradata) {

            av_buffer_unref(&filtered_buf);

            return AVERROR(ENOMEM);

        }

        *data = extradata;

        *size = extradata_size;

        bytestream2_init_writer(&pb_extradata, extradata, extradata_size);

        if (s->remove)

            bytestream2_init_writer(&pb_filtered_data, filtered_buf->data, filtered_size);

        for (i = 0; i < s->av1_pkt.nb_obus; i++) {

            AV1OBU *obu = &s->av1_pkt.obus[i];

            if (obu_is_global(obu)) {

                bytestream2_put_bufferu(&pb_extradata, obu->raw_data, obu->raw_size);

            } else if (s->remove) {

                bytestream2_put_bufferu(&pb_filtered_data, obu->raw_data, obu->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_h2645(AVBSFContext *ctx, AVPacket *pkt,

                                   uint8_t **data, int *size)

{

    static const int extradata_nal_types_vvc[] = {

        VVC_VPS_NUT, VVC_SPS_NUT, VVC_PPS_NUT,

    };

    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;

    size_t nb_extradata_nal_types;

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

    if (ctx->par_in->codec_id == AV_CODEC_ID_VVC) {

        extradata_nal_types    = extradata_nal_types_vvc;

        nb_extradata_nal_types = FF_ARRAY_ELEMS(extradata_nal_types_vvc);

    } else 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, ctx->par_in->codec_id, H2645_FLAG_SMALL_PADDING);

    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_VVC) {

                if (nal->type == VVC_SPS_NUT) has_sps = 1;

                if (nal->type == VVC_VPS_NUT) has_vps = 1;

            } else 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_VVC  && has_sps) ||

         (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 = NULL;

        PutByteContext pb_filtered_data, pb_extradata;

        uint8_t *extradata;

        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);

        }

        extradata = av_malloc(extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);

        if (!extradata) {

            av_buffer_unref(&filtered_buf);

            return AVERROR(ENOMEM);

        }

        *data = extradata;

        *size = extradata_size;

        bytestream2_init_writer(&pb_extradata, extradata, extradata_size);

        if (s->remove)

            bytestream2_init_writer(&pb_filtered_data, filtered_buf->data, filtered_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)) {

                bytestream2_put_be24u(&pb_extradata, 1); //startcode

                bytestream2_put_bufferu(&pb_extradata, nal->raw_data, nal->raw_size);

            } else if (s->remove) {

                bytestream2_put_be24u(&pb_filtered_data, 1); // startcode

                bytestream2_put_bufferu(&pb_filtered_data, nal->raw_data, 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);

        *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) {

            *size = i - 3;

            *data = av_malloc(*size + AV_INPUT_BUFFER_PADDING_SIZE);

            if (!*data)

                return AVERROR(ENOMEM);

            memcpy(*data, pkt->data, *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);

                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_AV1,        extract_extradata_av1     },

    { AV_CODEC_ID_AVS2,       extract_extradata_mpeg4   },

    { AV_CODEC_ID_AVS3,       extract_extradata_mpeg4   },

    { 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     },

    { AV_CODEC_ID_VVC,        extract_extradata_h2645   },

};

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) {

        memset(extradata + extradata_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);

        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_av1_packet_uninit(&s->av1_pkt);

    ff_h2645_packet_uninit(&s->h2645_pkt);

}

static const enum AVCodecID codec_ids[] = {

    AV_CODEC_ID_AV1,

    AV_CODEC_ID_AVS2,

    AV_CODEC_ID_AVS3,

    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_VVC,

    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 FFBitStreamFilter ff_extract_extradata_bsf = {

    .p.name         = "extract_extradata",

    .p.codec_ids    = codec_ids,

    .p.priv_class   = &extract_extradata_class,

    .priv_data_size = sizeof(ExtractExtradataContext),

    .init           = extract_extradata_init,

    .filter         = extract_extradata_filter,

    .close          = extract_extradata_close,

};