/*
  * DXVA2 HEVC HW acceleration.
  *
  * copyright (c) 2014 - 2015 Hendrik Leppkes
  *
  * 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/avassert.h"
 
 #include "hevc.h"
 

 // The headers above may include w32threads.h, which uses the original
 // _WIN32_WINNT define, while dxva2_internal.h redefines it to target a
 // potentially newer version.
 #include "dxva2_internal.h"
 

 #define MAX_SLICES 256
 
 struct hevc_dxva2_picture_context {
     DXVA_PicParams_HEVC   pp;
     DXVA_Qmatrix_HEVC     qm;
     unsigned              slice_count;
     DXVA_Slice_HEVC_Short slice_short[MAX_SLICES];
     const uint8_t         *bitstream;
     unsigned              bitstream_size;
 };
 
 static void fill_picture_entry(DXVA_PicEntry_HEVC *pic,
                                unsigned index, unsigned flag)
 {
     av_assert0((index & 0x7f) == index && (flag & 0x01) == flag);
     pic->bPicEntry = index | (flag << 7);
 }
 
 static int get_refpic_index(const DXVA_PicParams_HEVC *pp, int surface_index)
 {
     int i;
     for (i = 0; i < FF_ARRAY_ELEMS(pp->RefPicList); i++) {
         if ((pp->RefPicList[i].bPicEntry & 0x7f) == surface_index)
           return i;
     }
     return 0xff;
 }
 

 static void fill_picture_parameters(const AVCodecContext *avctx, AVDXVAContext *ctx, const HEVCContext *h,

                                     DXVA_PicParams_HEVC *pp)
 {
     const HEVCFrame *current_picture = h->ref;

     const HEVCSPS *sps = h->ps.sps;
     const HEVCPPS *pps = h->ps.pps;

     int i, j;

 
     memset(pp, 0, sizeof(*pp));
 

     pp->PicWidthInMinCbsY  = sps->min_cb_width;
     pp->PicHeightInMinCbsY = sps->min_cb_height;

     pp->wFormatAndSequenceInfoFlags = (sps->chroma_format_idc             <<  0) |
                                       (sps->separate_colour_plane_flag    <<  2) |
                                       ((sps->bit_depth - 8)               <<  3) |
                                       ((sps->bit_depth - 8)               <<  6) |
                                       ((sps->log2_max_poc_lsb - 4)        <<  9) |

                                       (0                                  << 13) |
                                       (0                                  << 14) |
                                       (0                                  << 15);
 

     fill_picture_entry(&pp->CurrPic, ff_dxva2_get_surface_index(avctx, ctx, current_picture->frame), 0);

     pp->sps_max_dec_pic_buffering_minus1         = sps->temporal_layer[sps->max_sub_layers - 1].max_dec_pic_buffering - 1;
     pp->log2_min_luma_coding_block_size_minus3   = sps->log2_min_cb_size - 3;
     pp->log2_diff_max_min_luma_coding_block_size = sps->log2_diff_max_min_coding_block_size;
     pp->log2_min_transform_block_size_minus2     = sps->log2_min_tb_size - 2;
     pp->log2_diff_max_min_transform_block_size   = sps->log2_max_trafo_size  - sps->log2_min_tb_size;
     pp->max_transform_hierarchy_depth_inter      = sps->max_transform_hierarchy_depth_inter;
     pp->max_transform_hierarchy_depth_intra      = sps->max_transform_hierarchy_depth_intra;
     pp->num_short_term_ref_pic_sets              = sps->nb_st_rps;
     pp->num_long_term_ref_pics_sps               = sps->num_long_term_ref_pics_sps;

     pp->num_ref_idx_l0_default_active_minus1     = pps->num_ref_idx_l0_default_active - 1;
     pp->num_ref_idx_l1_default_active_minus1     = pps->num_ref_idx_l1_default_active - 1;
     pp->init_qp_minus26                          = pps->pic_init_qp_minus26;

 
     if (h->sh.short_term_ref_pic_set_sps_flag == 0 && h->sh.short_term_rps) {

         pp->ucNumDeltaPocsOfRefRpsIdx            = h->sh.short_term_rps->rps_idx_num_delta_pocs;

         pp->wNumBitsForShortTermRPSInSlice       = h->sh.short_term_ref_pic_set_size;
     }
 

     pp->dwCodingParamToolFlags = (sps->scaling_list_enable_flag                  <<  0) |
                                  (sps->amp_enabled_flag                          <<  1) |
                                  (sps->sao_enabled                               <<  2) |
                                  (sps->pcm_enabled_flag                          <<  3) |
                                  ((sps->pcm_enabled_flag ? (sps->pcm.bit_depth - 1) : 0)            <<  4) |
                                  ((sps->pcm_enabled_flag ? (sps->pcm.bit_depth_chroma - 1) : 0)     <<  8) |
                                  ((sps->pcm_enabled_flag ? (sps->pcm.log2_min_pcm_cb_size - 3) : 0) << 12) |
                                  ((sps->pcm_enabled_flag ? (sps->pcm.log2_max_pcm_cb_size - sps->pcm.log2_min_pcm_cb_size) : 0) << 14) |
                                  (sps->pcm.loop_filter_disable_flag              << 16) |
                                  (sps->long_term_ref_pics_present_flag           << 17) |
                                  (sps->sps_temporal_mvp_enabled_flag             << 18) |
                                  (sps->sps_strong_intra_smoothing_enable_flag    << 19) |
                                  (pps->dependent_slice_segments_enabled_flag     << 20) |
                                  (pps->output_flag_present_flag                  << 21) |
                                  (pps->num_extra_slice_header_bits               << 22) |
                                  (pps->sign_data_hiding_flag                     << 25) |
                                  (pps->cabac_init_present_flag                   << 26) |

                                  (0                                              << 27);
 

     pp->dwCodingSettingPicturePropertyFlags = (pps->constrained_intra_pred_flag                   <<  0) |
                                               (pps->transform_skip_enabled_flag                   <<  1) |
                                               (pps->cu_qp_delta_enabled_flag                      <<  2) |
                                               (pps->pic_slice_level_chroma_qp_offsets_present_flag <<  3) |
                                               (pps->weighted_pred_flag                            <<  4) |
                                               (pps->weighted_bipred_flag                          <<  5) |
                                               (pps->transquant_bypass_enable_flag                 <<  6) |
                                               (pps->tiles_enabled_flag                            <<  7) |
                                               (pps->entropy_coding_sync_enabled_flag              <<  8) |
                                               (pps->uniform_spacing_flag                          <<  9) |
                                               ((pps->tiles_enabled_flag ? pps->loop_filter_across_tiles_enabled_flag : 0) << 10) |
                                               (pps->seq_loop_filter_across_slices_enabled_flag    << 11) |
                                               (pps->deblocking_filter_override_enabled_flag       << 12) |
                                               (pps->disable_dbf                                   << 13) |
                                               (pps->lists_modification_present_flag               << 14) |
                                               (pps->slice_header_extension_present_flag           << 15) |

                                               (IS_IRAP(h)                                         << 16) |
                                               (IS_IDR(h)                                          << 17) |
                                               /* IntraPicFlag */
                                               (IS_IRAP(h)                                         << 18) |
                                               (0                                                  << 19);

     pp->pps_cb_qp_offset            = pps->cb_qp_offset;
     pp->pps_cr_qp_offset            = pps->cr_qp_offset;
     if (pps->tiles_enabled_flag) {
         pp->num_tile_columns_minus1 = pps->num_tile_columns - 1;
         pp->num_tile_rows_minus1    = pps->num_tile_rows - 1;
 
         if (!pps->uniform_spacing_flag) {
             for (i = 0; i < pps->num_tile_columns; i++)
                 pp->column_width_minus1[i] = pps->column_width[i] - 1;
 
             for (i = 0; i < pps->num_tile_rows; i++)
                 pp->row_height_minus1[i] = pps->row_height[i] - 1;

         }
     }
 

     pp->diff_cu_qp_delta_depth           = pps->diff_cu_qp_delta_depth;
     pp->pps_beta_offset_div2             = pps->beta_offset / 2;
     pp->pps_tc_offset_div2               = pps->tc_offset / 2;
     pp->log2_parallel_merge_level_minus2 = pps->log2_parallel_merge_level - 2;

     pp->CurrPicOrderCntVal               = h->poc;
 
     // fill RefPicList from the DPB

     for (i = 0, j = 0; i < FF_ARRAY_ELEMS(pp->RefPicList); i++) {
         const HEVCFrame *frame = NULL;
         while (!frame && j < FF_ARRAY_ELEMS(h->DPB)) {
             if (&h->DPB[j] != current_picture && (h->DPB[j].flags & (HEVC_FRAME_FLAG_LONG_REF | HEVC_FRAME_FLAG_SHORT_REF)))
                 frame = &h->DPB[j];

             j++;
         }

 
         if (frame) {
             fill_picture_entry(&pp->RefPicList[i], ff_dxva2_get_surface_index(avctx, ctx, frame->frame), !!(frame->flags & HEVC_FRAME_FLAG_LONG_REF));
             pp->PicOrderCntValList[i] = frame->poc;
         } else {
             pp->RefPicList[i].bPicEntry = 0xff;
             pp->PicOrderCntValList[i]   = 0;
         }

     }
 
     #define DO_REF_LIST(ref_idx, ref_list) { \
         const RefPicList *rpl = &h->rps[ref_idx]; \

         for (i = 0, j = 0; i < FF_ARRAY_ELEMS(pp->ref_list); i++) { \
             const HEVCFrame *frame = NULL; \
             while (!frame && j < rpl->nb_refs) \
                 frame = rpl->ref[j++]; \
             if (frame) \
                 pp->ref_list[i] = get_refpic_index(pp, ff_dxva2_get_surface_index(avctx, ctx, frame->frame)); \
             else \
                 pp->ref_list[i] = 0xff; \

         } \
     }
 
     // Fill short term and long term lists
     DO_REF_LIST(ST_CURR_BEF, RefPicSetStCurrBefore);
     DO_REF_LIST(ST_CURR_AFT, RefPicSetStCurrAfter);
     DO_REF_LIST(LT_CURR, RefPicSetLtCurr);
 

     pp->StatusReportFeedbackNumber = 1 + DXVA_CONTEXT_REPORT_ID(avctx, ctx)++;

 }
 

 static void fill_scaling_lists(AVDXVAContext *ctx, const HEVCContext *h, DXVA_Qmatrix_HEVC *qm)

 {

     unsigned i, j, pos;

     const ScalingList *sl = h->ps.pps->scaling_list_data_present_flag ?
                             &h->ps.pps->scaling_list : &h->ps.sps->scaling_list;

     memset(qm, 0, sizeof(*qm));
     for (i = 0; i < 6; i++) {

         for (j = 0; j < 16; j++) {
             pos = 4 * ff_hevc_diag_scan4x4_y[j] + ff_hevc_diag_scan4x4_x[j];
             qm->ucScalingLists0[i][j] = sl->sl[0][i][pos];
         }

 
         for (j = 0; j < 64; j++) {

             pos = 8 * ff_hevc_diag_scan8x8_y[j] + ff_hevc_diag_scan8x8_x[j];
             qm->ucScalingLists1[i][j] = sl->sl[1][i][pos];
             qm->ucScalingLists2[i][j] = sl->sl[2][i][pos];

 
             if (i < 2)

                 qm->ucScalingLists3[i][j] = sl->sl[3][i * 3][pos];

         }
 

         qm->ucScalingListDCCoefSizeID2[i] = sl->sl_dc[0][i];

         if (i < 2)

             qm->ucScalingListDCCoefSizeID3[i] = sl->sl_dc[1][i * 3];

     }
 }
 
 static void fill_slice_short(DXVA_Slice_HEVC_Short *slice,
                              unsigned position, unsigned size)
 {
     memset(slice, 0, sizeof(*slice));
     slice->BSNALunitDataLocation = position;
     slice->SliceBytesInBuffer    = size;
     slice->wBadSliceChopping     = 0;
 }
 
 static int commit_bitstream_and_slice_buffer(AVCodecContext *avctx,

                                              DECODER_BUFFER_DESC *bs,
                                              DECODER_BUFFER_DESC *sc)

 {
     const HEVCContext *h = avctx->priv_data;

     AVDXVAContext *ctx = avctx->hwaccel_context;

     const HEVCFrame *current_picture = h->ref;
     struct hevc_dxva2_picture_context *ctx_pic = current_picture->hwaccel_picture_private;
     DXVA_Slice_HEVC_Short *slice = NULL;
     void     *dxva_data_ptr;
     uint8_t  *dxva_data, *current, *end;
     unsigned dxva_size;
     void     *slice_data;
     unsigned slice_size;
     unsigned padding;
     unsigned i;

     unsigned type;

 
     /* Create an annex B bitstream buffer with only slice NAL and finalize slice */

 #if CONFIG_D3D11VA
     if (avctx->pix_fmt == AV_PIX_FMT_D3D11VA_VLD) {
         type = D3D11_VIDEO_DECODER_BUFFER_BITSTREAM;
         if (FAILED(ID3D11VideoContext_GetDecoderBuffer(D3D11VA_CONTEXT(ctx)->video_context,
                                                        D3D11VA_CONTEXT(ctx)->decoder,
                                                        type,
                                                        &dxva_size, &dxva_data_ptr)))
             return -1;
     }
 #endif
 #if CONFIG_DXVA2
     if (avctx->pix_fmt == AV_PIX_FMT_DXVA2_VLD) {
         type = DXVA2_BitStreamDateBufferType;
         if (FAILED(IDirectXVideoDecoder_GetBuffer(DXVA2_CONTEXT(ctx)->decoder,
                                                   type,
                                                   &dxva_data_ptr, &dxva_size)))
             return -1;
     }
 #endif

 
     dxva_data = dxva_data_ptr;
     current = dxva_data;
     end = dxva_data + dxva_size;
 
     for (i = 0; i < ctx_pic->slice_count; i++) {
         static const uint8_t start_code[] = { 0, 0, 1 };
         static const unsigned start_code_size = sizeof(start_code);
         unsigned position, size;
 
         slice = &ctx_pic->slice_short[i];
 
         position = slice->BSNALunitDataLocation;
         size     = slice->SliceBytesInBuffer;
         if (start_code_size + size > end - current) {
             av_log(avctx, AV_LOG_ERROR, "Failed to build bitstream");
             break;
         }
 
         slice->BSNALunitDataLocation = current - dxva_data;
         slice->SliceBytesInBuffer    = start_code_size + size;
 
         memcpy(current, start_code, start_code_size);
         current += start_code_size;
 
         memcpy(current, &ctx_pic->bitstream[position], size);
         current += size;
     }
     padding = FFMIN(128 - ((current - dxva_data) & 127), end - current);
     if (slice && padding > 0) {
         memset(current, 0, padding);
         current += padding;
 
         slice->SliceBytesInBuffer += padding;
     }

 #if CONFIG_D3D11VA
     if (avctx->pix_fmt == AV_PIX_FMT_D3D11VA_VLD)
         if (FAILED(ID3D11VideoContext_ReleaseDecoderBuffer(D3D11VA_CONTEXT(ctx)->video_context, D3D11VA_CONTEXT(ctx)->decoder, type)))
             return -1;
 #endif
 #if CONFIG_DXVA2
     if (avctx->pix_fmt == AV_PIX_FMT_DXVA2_VLD)
         if (FAILED(IDirectXVideoDecoder_ReleaseBuffer(DXVA2_CONTEXT(ctx)->decoder, type)))
             return -1;
 #endif

     if (i < ctx_pic->slice_count)
         return -1;
 

 #if CONFIG_D3D11VA
     if (avctx->pix_fmt == AV_PIX_FMT_D3D11VA_VLD) {
         D3D11_VIDEO_DECODER_BUFFER_DESC *dsc11 = bs;
         memset(dsc11, 0, sizeof(*dsc11));
         dsc11->BufferType           = type;
         dsc11->DataSize             = current - dxva_data;
         dsc11->NumMBsInBuffer       = 0;
 
         type = D3D11_VIDEO_DECODER_BUFFER_SLICE_CONTROL;
     }
 #endif
 #if CONFIG_DXVA2
     if (avctx->pix_fmt == AV_PIX_FMT_DXVA2_VLD) {
         DXVA2_DecodeBufferDesc *dsc2 = bs;
         memset(dsc2, 0, sizeof(*dsc2));
         dsc2->CompressedBufferType = type;
         dsc2->DataSize             = current - dxva_data;
         dsc2->NumMBsInBuffer       = 0;
 
         type = DXVA2_SliceControlBufferType;
     }
 #endif

 
     slice_data = ctx_pic->slice_short;
     slice_size = ctx_pic->slice_count * sizeof(*ctx_pic->slice_short);
 

     av_assert0(((current - dxva_data) & 127) == 0);

     return ff_dxva2_commit_buffer(avctx, ctx, sc,

                                   type,

                                   slice_data, slice_size, 0);
 }
 
 
 static int dxva2_hevc_start_frame(AVCodecContext *avctx,
                                   av_unused const uint8_t *buffer,
                                   av_unused uint32_t size)
 {
     const HEVCContext *h = avctx->priv_data;

     AVDXVAContext *ctx = avctx->hwaccel_context;

     struct hevc_dxva2_picture_context *ctx_pic = h->ref->hwaccel_picture_private;
 

     if (DXVA_CONTEXT_DECODER(avctx, ctx) == NULL ||
         DXVA_CONTEXT_CFG(avctx, ctx) == NULL ||
         DXVA_CONTEXT_COUNT(avctx, ctx) <= 0)

         return -1;
     av_assert0(ctx_pic);
 
     /* Fill up DXVA_PicParams_HEVC */

     fill_picture_parameters(avctx, ctx, h, &ctx_pic->pp);

 
     /* Fill up DXVA_Qmatrix_HEVC */
     fill_scaling_lists(ctx, h, &ctx_pic->qm);
 
     ctx_pic->slice_count    = 0;
     ctx_pic->bitstream_size = 0;
     ctx_pic->bitstream      = NULL;
     return 0;
 }
 
 static int dxva2_hevc_decode_slice(AVCodecContext *avctx,
                                    const uint8_t *buffer,
                                    uint32_t size)
 {
     const HEVCContext *h = avctx->priv_data;
     const HEVCFrame *current_picture = h->ref;
     struct hevc_dxva2_picture_context *ctx_pic = current_picture->hwaccel_picture_private;
     unsigned position;
 
     if (ctx_pic->slice_count >= MAX_SLICES)
         return -1;
 
     if (!ctx_pic->bitstream)
         ctx_pic->bitstream = buffer;
     ctx_pic->bitstream_size += size;
 
     position = buffer - ctx_pic->bitstream;
     fill_slice_short(&ctx_pic->slice_short[ctx_pic->slice_count], position, size);
     ctx_pic->slice_count++;
 
     return 0;
 }
 
 static int dxva2_hevc_end_frame(AVCodecContext *avctx)
 {
     HEVCContext *h = avctx->priv_data;
     struct hevc_dxva2_picture_context *ctx_pic = h->ref->hwaccel_picture_private;
     int scale = ctx_pic->pp.dwCodingParamToolFlags & 1;
     int ret;
 
     if (ctx_pic->slice_count <= 0 || ctx_pic->bitstream_size <= 0)
         return -1;
 
     ret = ff_dxva2_common_end_frame(avctx, h->ref->frame,
                                     &ctx_pic->pp, sizeof(ctx_pic->pp),
                                     scale ? &ctx_pic->qm : NULL, scale ? sizeof(ctx_pic->qm) : 0,
                                     commit_bitstream_and_slice_buffer);
     return ret;
 }
 

 #if CONFIG_HEVC_DXVA2_HWACCEL

 AVHWAccel ff_hevc_dxva2_hwaccel = {
     .name           = "hevc_dxva2",
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_HEVC,
     .pix_fmt        = AV_PIX_FMT_DXVA2_VLD,
     .start_frame    = dxva2_hevc_start_frame,
     .decode_slice   = dxva2_hevc_decode_slice,
     .end_frame      = dxva2_hevc_end_frame,
     .frame_priv_data_size = sizeof(struct hevc_dxva2_picture_context),
 };

 #endif
 
 #if CONFIG_HEVC_D3D11VA_HWACCEL
 AVHWAccel ff_hevc_d3d11va_hwaccel = {
     .name           = "hevc_d3d11va",
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_HEVC,
     .pix_fmt        = AV_PIX_FMT_D3D11VA_VLD,
     .start_frame    = dxva2_hevc_start_frame,
     .decode_slice   = dxva2_hevc_decode_slice,
     .end_frame      = dxva2_hevc_end_frame,
     .frame_priv_data_size = sizeof(struct hevc_dxva2_picture_context),
 };
 #endif