/*

  * HEVC video decoder

  *
  * Copyright (C) 2012 - 2013 Guillaume Martres
  *
  * 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
  */
 

 #ifndef AVCODEC_HEVCDEC_H
 #define AVCODEC_HEVCDEC_H

 #include <stdatomic.h>
 

 #include "libavutil/buffer.h"

 #include "libavutil/md5.h"

 
 #include "avcodec.h"

 #include "bswapdsp.h"

 #include "cabac.h"
 #include "get_bits.h"
 #include "hevcpred.h"

 #include "h2645_parse.h"

 #include "hevc.h"

 #include "hevc_ps.h"

 #include "hevc_sei.h"

 #include "hevcdsp.h"
 #include "internal.h"
 #include "thread.h"
 #include "videodsp.h"
 

 #define MAX_NB_THREADS 16
 #define SHIFT_CTB_WPP 2
 

 //TODO: check if this is really the maximum
 #define MAX_TRANSFORM_DEPTH 5
 
 #define MAX_TB_SIZE 32
 #define MAX_QP 51
 #define DEFAULT_INTRA_TC_OFFSET 2
 

 #define HEVC_CONTEXTS 199

 
 #define MRG_MAX_NUM_CANDS     5
 
 #define L0 0
 #define L1 1
 
 #define EPEL_EXTRA_BEFORE 1
 #define EPEL_EXTRA_AFTER  2
 #define EPEL_EXTRA        3

 #define QPEL_EXTRA_BEFORE 3
 #define QPEL_EXTRA_AFTER  4
 #define QPEL_EXTRA        7

 #define EDGE_EMU_BUFFER_STRIDE 80
 

 /**
  * Value of the luma sample at position (x, y) in the 2D array tab.
  */
 #define SAMPLE(tab, x, y) ((tab)[(y) * s->sps->width + (x)])

 #define SAMPLE_CTB(tab, x, y) ((tab)[(y) * min_cb_width + (x)])

 #define IS_IDR(s) ((s)->nal_unit_type == HEVC_NAL_IDR_W_RADL || (s)->nal_unit_type == HEVC_NAL_IDR_N_LP)
 #define IS_BLA(s) ((s)->nal_unit_type == HEVC_NAL_BLA_W_RADL || (s)->nal_unit_type == HEVC_NAL_BLA_W_LP || \
                    (s)->nal_unit_type == HEVC_NAL_BLA_N_LP)

 #define IS_IRAP(s) ((s)->nal_unit_type >= 16 && (s)->nal_unit_type <= 23)

 
 enum RPSType {
     ST_CURR_BEF = 0,
     ST_CURR_AFT,
     ST_FOLL,
     LT_CURR,
     LT_FOLL,
     NB_RPS_TYPE,
 };
 
 enum SyntaxElement {
     SAO_MERGE_FLAG = 0,
     SAO_TYPE_IDX,
     SAO_EO_CLASS,
     SAO_BAND_POSITION,
     SAO_OFFSET_ABS,
     SAO_OFFSET_SIGN,
     END_OF_SLICE_FLAG,
     SPLIT_CODING_UNIT_FLAG,
     CU_TRANSQUANT_BYPASS_FLAG,
     SKIP_FLAG,
     CU_QP_DELTA,
     PRED_MODE_FLAG,
     PART_MODE,
     PCM_FLAG,
     PREV_INTRA_LUMA_PRED_FLAG,
     MPM_IDX,
     REM_INTRA_LUMA_PRED_MODE,
     INTRA_CHROMA_PRED_MODE,
     MERGE_FLAG,
     MERGE_IDX,
     INTER_PRED_IDC,
     REF_IDX_L0,
     REF_IDX_L1,
     ABS_MVD_GREATER0_FLAG,
     ABS_MVD_GREATER1_FLAG,
     ABS_MVD_MINUS2,
     MVD_SIGN_FLAG,
     MVP_LX_FLAG,
     NO_RESIDUAL_DATA_FLAG,
     SPLIT_TRANSFORM_FLAG,
     CBF_LUMA,
     CBF_CB_CR,
     TRANSFORM_SKIP_FLAG,

     EXPLICIT_RDPCM_FLAG,
     EXPLICIT_RDPCM_DIR_FLAG,

     LAST_SIGNIFICANT_COEFF_X_PREFIX,
     LAST_SIGNIFICANT_COEFF_Y_PREFIX,
     LAST_SIGNIFICANT_COEFF_X_SUFFIX,
     LAST_SIGNIFICANT_COEFF_Y_SUFFIX,
     SIGNIFICANT_COEFF_GROUP_FLAG,
     SIGNIFICANT_COEFF_FLAG,
     COEFF_ABS_LEVEL_GREATER1_FLAG,
     COEFF_ABS_LEVEL_GREATER2_FLAG,
     COEFF_ABS_LEVEL_REMAINING,
     COEFF_SIGN_FLAG,

     LOG2_RES_SCALE_ABS,
     RES_SCALE_SIGN_FLAG,
     CU_CHROMA_QP_OFFSET_FLAG,
     CU_CHROMA_QP_OFFSET_IDX,

 };
 
 enum PartMode {
     PART_2Nx2N = 0,
     PART_2NxN  = 1,
     PART_Nx2N  = 2,
     PART_NxN   = 3,
     PART_2NxnU = 4,
     PART_2NxnD = 5,
     PART_nLx2N = 6,
     PART_nRx2N = 7,
 };
 
 enum PredMode {
     MODE_INTER = 0,
     MODE_INTRA,
     MODE_SKIP,
 };
 
 enum InterPredIdc {
     PRED_L0 = 0,
     PRED_L1,
     PRED_BI,
 };
 

 enum PredFlag {
     PF_INTRA = 0,
     PF_L0,
     PF_L1,
     PF_BI,
 };
 

 enum IntraPredMode {
     INTRA_PLANAR = 0,
     INTRA_DC,
     INTRA_ANGULAR_2,
     INTRA_ANGULAR_3,
     INTRA_ANGULAR_4,
     INTRA_ANGULAR_5,
     INTRA_ANGULAR_6,
     INTRA_ANGULAR_7,
     INTRA_ANGULAR_8,
     INTRA_ANGULAR_9,
     INTRA_ANGULAR_10,
     INTRA_ANGULAR_11,
     INTRA_ANGULAR_12,
     INTRA_ANGULAR_13,
     INTRA_ANGULAR_14,
     INTRA_ANGULAR_15,
     INTRA_ANGULAR_16,
     INTRA_ANGULAR_17,
     INTRA_ANGULAR_18,
     INTRA_ANGULAR_19,
     INTRA_ANGULAR_20,
     INTRA_ANGULAR_21,
     INTRA_ANGULAR_22,
     INTRA_ANGULAR_23,
     INTRA_ANGULAR_24,
     INTRA_ANGULAR_25,
     INTRA_ANGULAR_26,
     INTRA_ANGULAR_27,
     INTRA_ANGULAR_28,
     INTRA_ANGULAR_29,
     INTRA_ANGULAR_30,
     INTRA_ANGULAR_31,
     INTRA_ANGULAR_32,
     INTRA_ANGULAR_33,
     INTRA_ANGULAR_34,
 };
 
 enum SAOType {
     SAO_NOT_APPLIED = 0,
     SAO_BAND,
     SAO_EDGE,

     SAO_APPLIED

 };
 
 enum SAOEOClass {
     SAO_EO_HORIZ = 0,
     SAO_EO_VERT,
     SAO_EO_135D,
     SAO_EO_45D,
 };
 
 enum ScanType {
     SCAN_DIAG = 0,
     SCAN_HORIZ,
     SCAN_VERT,
 };
 
 typedef struct RefPicList {

     struct HEVCFrame *ref[HEVC_MAX_REFS];
     int list[HEVC_MAX_REFS];
     int isLongTerm[HEVC_MAX_REFS];

     int nb_refs;
 } RefPicList;
 
 typedef struct RefPicListTab {
     RefPicList refPicList[2];
 } RefPicListTab;
 
 typedef struct CodingUnit {

     int x;
     int y;

     enum PredMode pred_mode;    ///< PredMode
     enum PartMode part_mode;    ///< PartMode

     // Inferred parameters

     uint8_t intra_split_flag;   ///< IntraSplitFlag
     uint8_t max_trafo_depth;    ///< MaxTrafoDepth

     uint8_t cu_transquant_bypass_flag;

 } CodingUnit;
 
 typedef struct Mv {

     int16_t x;  ///< horizontal component of motion vector
     int16_t y;  ///< vertical component of motion vector

 } Mv;
 
 typedef struct MvField {

     DECLARE_ALIGNED(4, Mv, mv)[2];

     int8_t ref_idx[2];

     int8_t pred_flag;

 } MvField;
 
 typedef struct NeighbourAvailable {
     int cand_bottom_left;
     int cand_left;
     int cand_up;
     int cand_up_left;
     int cand_up_right;
     int cand_up_right_sap;
 } NeighbourAvailable;
 
 typedef struct PredictionUnit {
     int mpm_idx;
     int rem_intra_luma_pred_mode;
     uint8_t intra_pred_mode[4];
     Mv mvd;

     uint8_t merge_flag;

     uint8_t intra_pred_mode_c[4];
     uint8_t chroma_mode_c[4];

 } PredictionUnit;
 
 typedef struct TransformUnit {
     int cu_qp_delta;
 

     int res_scale_val;
 

     // Inferred parameters;

     int intra_pred_mode;
     int intra_pred_mode_c;
     int chroma_mode_c;

     uint8_t is_cu_qp_delta_coded;

     uint8_t is_cu_chroma_qp_offset_coded;
     int8_t  cu_qp_offset_cb;
     int8_t  cu_qp_offset_cr;
     uint8_t cross_pf;

 } TransformUnit;
 
 typedef struct DBParams {
     int beta_offset;
     int tc_offset;
 } DBParams;
 
 #define HEVC_FRAME_FLAG_OUTPUT    (1 << 0)
 #define HEVC_FRAME_FLAG_SHORT_REF (1 << 1)
 #define HEVC_FRAME_FLAG_LONG_REF  (1 << 2)

 #define HEVC_FRAME_FLAG_BUMPING   (1 << 3)

 
 typedef struct HEVCFrame {
     AVFrame *frame;
     ThreadFrame tf;
     MvField *tab_mvf;
     RefPicList *refPicList;
     RefPicListTab **rpl_tab;
     int ctb_count;

     int poc;

     struct HEVCFrame *collocated_ref;
 

     AVBufferRef *tab_mvf_buf;
     AVBufferRef *rpl_tab_buf;
     AVBufferRef *rpl_buf;

     AVBufferRef *hwaccel_priv_buf;
     void *hwaccel_picture_private;
 

     /**
      * A sequence counter, so that old frames are output first
      * after a POC reset
      */
     uint16_t sequence;
 

     /**
      * A combination of HEVC_FRAME_FLAG_*
      */
     uint8_t flags;

 } HEVCFrame;
 
 typedef struct HEVCLocalContext {
     uint8_t cabac_state[HEVC_CONTEXTS];

     uint8_t stat_coeff[4];
 

     uint8_t first_qp_group;
 

     GetBitContext gb;
     CABACContext cc;

     int8_t qp_y;
     int8_t curr_qp_y;

     int qPy_pred;
 

     TransformUnit tu;
 

     uint8_t ctb_left_flag;
     uint8_t ctb_up_flag;
     uint8_t ctb_up_right_flag;
     uint8_t ctb_up_left_flag;
     int     end_of_tiles_x;
     int     end_of_tiles_y;

     /* +7 is for subpixel interpolation, *2 for high bit depths */
     DECLARE_ALIGNED(32, uint8_t, edge_emu_buffer)[(MAX_PB_SIZE + 7) * EDGE_EMU_BUFFER_STRIDE * 2];

     /* The extended size between the new edge emu buffer is abused by SAO */

     DECLARE_ALIGNED(32, uint8_t, edge_emu_buffer2)[(MAX_PB_SIZE + 7) * EDGE_EMU_BUFFER_STRIDE * 2];

     DECLARE_ALIGNED(32, int16_t, tmp)[MAX_PB_SIZE * MAX_PB_SIZE];

     int ct_depth;

     CodingUnit cu;
     PredictionUnit pu;
     NeighbourAvailable na;

 #define BOUNDARY_LEFT_SLICE     (1 << 0)
 #define BOUNDARY_LEFT_TILE      (1 << 1)
 #define BOUNDARY_UPPER_SLICE    (1 << 2)
 #define BOUNDARY_UPPER_TILE     (1 << 3)
     /* properties of the boundary of the current CTB for the purposes
      * of the deblocking filter */
     int boundary_flags;

 } HEVCLocalContext;
 
 typedef struct HEVCContext {
     const AVClass *c;  // needed by private avoptions

     AVCodecContext *avctx;

     struct HEVCContext  *sList[MAX_NB_THREADS];

     HEVCLocalContext    *HEVClcList[MAX_NB_THREADS];
     HEVCLocalContext    *HEVClc;

 
     uint8_t             threads_type;
     uint8_t             threads_number;

 
     int                 width;
     int                 height;
 

     uint8_t *cabac_state;

     /** 1 if the independent slice segment header was successfully parsed */
     uint8_t slice_initialized;
 

     AVFrame *frame;
     AVFrame *output_frame;

     uint8_t *sao_pixel_buffer_h[3];
     uint8_t *sao_pixel_buffer_v[3];

     HEVCParamSets ps;

     HEVCSEI sei;

     struct AVMD5 *md5_ctx;

     AVBufferPool *tab_mvf_pool;
     AVBufferPool *rpl_tab_pool;
 

     ///< candidate references for the current frame
     RefPicList rps[5];
 
     SliceHeader sh;
     SAOParams *sao;
     DBParams *deblock;

     enum HEVCNALUnitType nal_unit_type;

     int temporal_id;  ///< temporal_id_plus1 - 1
     HEVCFrame *ref;
     HEVCFrame DPB[32];
     int poc;
     int pocTid0;
     int slice_idx; ///< number of the slice being currently decoded
     int eos;       ///< current packet contains an EOS/EOB NAL

     int last_eos;  ///< last packet contains an EOS/EOB NAL

     int max_ra;
     int bs_width;
     int bs_height;
 
     int is_decoded;

     int no_rasl_output_flag;

 
     HEVCPredContext hpc;
     HEVCDSPContext hevcdsp;
     VideoDSPContext vdsp;

     BswapDSPContext bdsp;

     int8_t *qp_y_tab;
     uint8_t *horizontal_bs;
     uint8_t *vertical_bs;
 
     int32_t *tab_slice_address;
 
     //  CU
     uint8_t *skip_flag;
     uint8_t *tab_ct_depth;
     // PU
     uint8_t *tab_ipm;
 
     uint8_t *cbf_luma; // cbf_luma of colocated TU
     uint8_t *is_pcm;
 
     // CTB-level flags affecting loop filter operation
     uint8_t *filter_slice_edges;
 
     /** used on BE to byteswap the lines for checksumming */
     uint8_t *checksum_buf;
     int      checksum_buf_size;
 
     /**
      * Sequence counters for decoded and output frames, so that old
      * frames are output first after a POC reset
      */
     uint16_t seq_decode;
     uint16_t seq_output;
 

     int enable_parallel_tiles;

     atomic_int wpp_err;

     const uint8_t *data;

     H2645Packet pkt;

     // type of the first VCL NAL of the current frame

     enum HEVCNALUnitType first_nal_type;

     uint8_t context_initialized;

     int is_nalff;           ///< this flag is != 0 if bitstream is encapsulated

                             ///< as a format defined in 14496-15
     int apply_defdispwin;

     int nal_length_size;    ///< Number of bytes used for nal length (1, 2 or 4)

     int nuh_layer_id;

 } HEVCContext;
 
 /**
  * Mark all frames in DPB as unused for reference.
  */
 void ff_hevc_clear_refs(HEVCContext *s);
 
 /**
  * Drop all frames currently in DPB.
  */
 void ff_hevc_flush_dpb(HEVCContext *s);
 

 RefPicList *ff_hevc_get_ref_list(HEVCContext *s, HEVCFrame *frame,
                                  int x0, int y0);

 
 /**
  * Construct the reference picture sets for the current frame.
  */
 int ff_hevc_frame_rps(HEVCContext *s);
 
 /**
  * Construct the reference picture list(s) for the current slice.
  */
 int ff_hevc_slice_rpl(HEVCContext *s);
 
 void ff_hevc_save_states(HEVCContext *s, int ctb_addr_ts);

 int ff_hevc_cabac_init(HEVCContext *s, int ctb_addr_ts);

 int ff_hevc_sao_merge_flag_decode(HEVCContext *s);
 int ff_hevc_sao_type_idx_decode(HEVCContext *s);
 int ff_hevc_sao_band_position_decode(HEVCContext *s);
 int ff_hevc_sao_offset_abs_decode(HEVCContext *s);
 int ff_hevc_sao_offset_sign_decode(HEVCContext *s);
 int ff_hevc_sao_eo_class_decode(HEVCContext *s);
 int ff_hevc_end_of_slice_flag_decode(HEVCContext *s);
 int ff_hevc_cu_transquant_bypass_flag_decode(HEVCContext *s);

 int ff_hevc_skip_flag_decode(HEVCContext *s, int x0, int y0,
                              int x_cb, int y_cb);

 int ff_hevc_pred_mode_decode(HEVCContext *s);

 int ff_hevc_split_coding_unit_flag_decode(HEVCContext *s, int ct_depth,
                                           int x0, int y0);

 int ff_hevc_part_mode_decode(HEVCContext *s, int log2_cb_size);
 int ff_hevc_pcm_flag_decode(HEVCContext *s);
 int ff_hevc_prev_intra_luma_pred_flag_decode(HEVCContext *s);
 int ff_hevc_mpm_idx_decode(HEVCContext *s);
 int ff_hevc_rem_intra_luma_pred_mode_decode(HEVCContext *s);
 int ff_hevc_intra_chroma_pred_mode_decode(HEVCContext *s);
 int ff_hevc_merge_idx_decode(HEVCContext *s);
 int ff_hevc_merge_flag_decode(HEVCContext *s);
 int ff_hevc_inter_pred_idc_decode(HEVCContext *s, int nPbW, int nPbH);
 int ff_hevc_ref_idx_lx_decode(HEVCContext *s, int num_ref_idx_lx);
 int ff_hevc_mvp_lx_flag_decode(HEVCContext *s);
 int ff_hevc_no_residual_syntax_flag_decode(HEVCContext *s);
 int ff_hevc_split_transform_flag_decode(HEVCContext *s, int log2_trafo_size);
 int ff_hevc_cbf_cb_cr_decode(HEVCContext *s, int trafo_depth);
 int ff_hevc_cbf_luma_decode(HEVCContext *s, int trafo_depth);

 int ff_hevc_log2_res_scale_abs(HEVCContext *s, int idx);
 int ff_hevc_res_scale_sign_flag(HEVCContext *s, int idx);

 
 /**
  * Get the number of candidate references for the current frame.
  */
 int ff_hevc_frame_nb_refs(HEVCContext *s);

 int ff_hevc_set_new_ref(HEVCContext *s, AVFrame **frame, int poc);
 
 /**
  * Find next frame in output order and put a reference to it in frame.
  * @return 1 if a frame was output, 0 otherwise
  */
 int ff_hevc_output_frame(HEVCContext *s, AVFrame *frame, int flush);
 

 void ff_hevc_bump_frame(HEVCContext *s);
 

 void ff_hevc_unref_frame(HEVCContext *s, HEVCFrame *frame, int flags);
 

 void ff_hevc_set_neighbour_available(HEVCContext *s, int x0, int y0,
                                      int nPbW, int nPbH);
 void ff_hevc_luma_mv_merge_mode(HEVCContext *s, int x0, int y0,
                                 int nPbW, int nPbH, int log2_cb_size,
                                 int part_idx, int merge_idx, MvField *mv);
 void ff_hevc_luma_mv_mvp_mode(HEVCContext *s, int x0, int y0,
                               int nPbW, int nPbH, int log2_cb_size,
                               int part_idx, int merge_idx,
                               MvField *mv, int mvp_lx_flag, int LX);

 void ff_hevc_set_qPy(HEVCContext *s, int xBase, int yBase,

                      int log2_cb_size);
 void ff_hevc_deblocking_boundary_strengths(HEVCContext *s, int x0, int y0,

                                            int log2_trafo_size);

 int ff_hevc_cu_qp_delta_sign_flag(HEVCContext *s);
 int ff_hevc_cu_qp_delta_abs(HEVCContext *s);

 int ff_hevc_cu_chroma_qp_offset_flag(HEVCContext *s);
 int ff_hevc_cu_chroma_qp_offset_idx(HEVCContext *s);

 void ff_hevc_hls_filter(HEVCContext *s, int x, int y, int ctb_size);

 void ff_hevc_hls_filters(HEVCContext *s, int x_ctb, int y_ctb, int ctb_size);

 void ff_hevc_hls_residual_coding(HEVCContext *s, int x0, int y0,
                                  int log2_trafo_size, enum ScanType scan_idx,
                                  int c_idx);

 void ff_hevc_hls_mvd_coding(HEVCContext *s, int x0, int y0, int log2_cb_size);
 

 extern const uint8_t ff_hevc_qpel_extra_before[4];
 extern const uint8_t ff_hevc_qpel_extra_after[4];
 extern const uint8_t ff_hevc_qpel_extra[4];
 

 #endif /* AVCODEC_HEVCDEC_H */