/*
  * AVS encoding using the xavs library
  * Copyright (C) 2010 Amanda, Y.N. Wu <amanda11192003@gmail.com>
  *
  * 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 <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <math.h>
 #include <stdint.h>

 #include <float.h>

 #include <xavs.h>
 #include "avcodec.h"

 #include "internal.h"

 #include "libavutil/internal.h"
 #include "libavutil/mem.h"

 #include "libavutil/opt.h"

 
 #define END_OF_STREAM 0x001
 
 #define XAVS_PART_I8X8 0x002 /* Analyze i8x8 (requires 8x8 transform) */
 #define XAVS_PART_P8X8 0x010 /* Analyze p16x8, p8x16 and p8x8 */
 #define XAVS_PART_B8X8 0x100 /* Analyze b16x8, b*/
 
 typedef struct XavsContext {

     AVClass        *class;

     xavs_param_t    params;
     xavs_t         *enc;
     xavs_picture_t  pic;
     uint8_t        *sei;
     int             sei_size;
     AVFrame         out_pic;
     int             end_of_stream;

     float crf;
     int cqp;
     int b_bias;
     float cplxblur;
     int direct_pred;
     int aud;
     int fast_pskip;
     int mbtree;
     int mixed_refs;

 
     int64_t *pts_buffer;
     int out_frame_count;

 } XavsContext;
 
 static void XAVS_log(void *p, int level, const char *fmt, va_list args)
 {
     static const int level_map[] = {
         [XAVS_LOG_ERROR]   = AV_LOG_ERROR,
         [XAVS_LOG_WARNING] = AV_LOG_WARNING,
         [XAVS_LOG_INFO]    = AV_LOG_INFO,
         [XAVS_LOG_DEBUG]   = AV_LOG_DEBUG
     };
 
     if (level < 0 || level > XAVS_LOG_DEBUG)
         return;
 
     av_vlog(p, level_map[level], fmt, args);
 }
 

 static int encode_nals(AVCodecContext *ctx, AVPacket *pkt,
                        xavs_nal_t *nals, int nnal)

 {
     XavsContext *x4 = ctx->priv_data;

     uint8_t *p;
     int i, s, ret, size = x4->sei_size + FF_MIN_BUFFER_SIZE;
 
     if (!nnal)
         return 0;
 
     for (i = 0; i < nnal; i++)
         size += nals[i].i_payload;
 

     if ((ret = ff_alloc_packet2(ctx, pkt, size)) < 0)

         return ret;
     p = pkt->data;

 
     /* Write the SEI as part of the first frame. */
     if (x4->sei_size > 0 && nnal > 0) {
         memcpy(p, x4->sei, x4->sei_size);
         p += x4->sei_size;
         x4->sei_size = 0;
     }
 
     for (i = 0; i < nnal; i++) {
         s = xavs_nal_encode(p, &size, 1, nals + i);
         if (s < 0)
             return -1;
         p += s;
     }

     pkt->size = p - pkt->data;

     return 1;

 }
 

 static int XAVS_frame(AVCodecContext *ctx, AVPacket *pkt,
                       const AVFrame *frame, int *got_packet)

 {
     XavsContext *x4 = ctx->priv_data;
     xavs_nal_t *nal;

     int nnal, i, ret;

     xavs_picture_t pic_out;
 
     x4->pic.img.i_csp   = XAVS_CSP_I420;
     x4->pic.img.i_plane = 3;
 
     if (frame) {
        for (i = 0; i < 3; i++) {
             x4->pic.img.plane[i] = frame->data[i];
             x4->pic.img.i_stride[i] = frame->linesize[i];
        }
 
         x4->pic.i_pts  = frame->pts;
         x4->pic.i_type = XAVS_TYPE_AUTO;

         x4->pts_buffer[ctx->frame_number % (ctx->max_b_frames+1)] = frame->pts;

     }
 
     if (xavs_encoder_encode(x4->enc, &nal, &nnal,
                             frame? &x4->pic: NULL, &pic_out) < 0)
     return -1;
 

     ret = encode_nals(ctx, pkt, nal, nnal);

     if (ret < 0)

         return -1;
 

     if (!ret) {
         if (!frame && !(x4->end_of_stream)) {

             if ((ret = ff_alloc_packet2(ctx, pkt, 4)) < 0)

                 return ret;
 
             pkt->data[0] = 0x0;
             pkt->data[1] = 0x0;
             pkt->data[2] = 0x01;
             pkt->data[3] = 0xb1;
             pkt->dts = 2*x4->pts_buffer[(x4->out_frame_count-1)%(ctx->max_b_frames+1)] -
                        x4->pts_buffer[(x4->out_frame_count-2)%(ctx->max_b_frames+1)];
             x4->end_of_stream = END_OF_STREAM;
             *got_packet = 1;
         }
         return 0;

     }

     x4->out_pic.pts = pic_out.i_pts;

     pkt->pts = pic_out.i_pts;
     if (ctx->has_b_frames) {
         if (!x4->out_frame_count)
             pkt->dts = pkt->pts - (x4->pts_buffer[1] - x4->pts_buffer[0]);
         else
             pkt->dts = x4->pts_buffer[(x4->out_frame_count-1)%(ctx->max_b_frames+1)];
     } else
         pkt->dts = pkt->pts;

 
     switch (pic_out.i_type) {
     case XAVS_TYPE_IDR:
     case XAVS_TYPE_I:

         x4->out_pic.pict_type = AV_PICTURE_TYPE_I;

         break;
     case XAVS_TYPE_P:

         x4->out_pic.pict_type = AV_PICTURE_TYPE_P;

         break;
     case XAVS_TYPE_B:
     case XAVS_TYPE_BREF:

         x4->out_pic.pict_type = AV_PICTURE_TYPE_B;

         break;
     }
 
     /* There is no IDR frame in AVS JiZhun */
     /* Sequence header is used as a flag */

     if (pic_out.i_type == XAVS_TYPE_I) {
         x4->out_pic.key_frame = 1;
         pkt->flags |= AV_PKT_FLAG_KEY;
     }

 
     x4->out_pic.quality   = (pic_out.i_qpplus1 - 1) * FF_QP2LAMBDA;
 

     x4->out_frame_count++;
     *got_packet = ret;
     return 0;

 }
 
 static av_cold int XAVS_close(AVCodecContext *avctx)
 {
     XavsContext *x4 = avctx->priv_data;
 
     av_freep(&avctx->extradata);
     av_free(x4->sei);

     av_freep(&x4->pts_buffer);

 
     if (x4->enc)
         xavs_encoder_close(x4->enc);
 
     return 0;
 }
 
 static av_cold int XAVS_init(AVCodecContext *avctx)
 {
     XavsContext *x4 = avctx->priv_data;
 
     x4->sei_size = 0;
     xavs_param_default(&x4->params);
 
     x4->params.pf_log               = XAVS_log;
     x4->params.p_log_private        = avctx;
     x4->params.i_keyint_max         = avctx->gop_size;

     if (avctx->bit_rate) {
         x4->params.rc.i_bitrate   = avctx->bit_rate / 1000;
         x4->params.rc.i_rc_method = XAVS_RC_ABR;
     }

     x4->params.rc.i_vbv_buffer_size = avctx->rc_buffer_size / 1000;
     x4->params.rc.i_vbv_max_bitrate = avctx->rc_max_rate    / 1000;
     x4->params.rc.b_stat_write      = avctx->flags & CODEC_FLAG_PASS1;
     if (avctx->flags & CODEC_FLAG_PASS2) {
         x4->params.rc.b_stat_read = 1;
     } else {

         if (x4->crf >= 0) {
             x4->params.rc.i_rc_method   = XAVS_RC_CRF;
             x4->params.rc.f_rf_constant = x4->crf;
         } else if (x4->cqp >= 0) {
             x4->params.rc.i_rc_method   = XAVS_RC_CQP;
             x4->params.rc.i_qp_constant = x4->cqp;
         }

     }
 

     if (x4->aud >= 0)
         x4->params.b_aud                      = x4->aud;
     if (x4->mbtree >= 0)
         x4->params.rc.b_mb_tree               = x4->mbtree;
     if (x4->direct_pred >= 0)
         x4->params.analyse.i_direct_mv_pred   = x4->direct_pred;
     if (x4->fast_pskip >= 0)
         x4->params.analyse.b_fast_pskip       = x4->fast_pskip;
     if (x4->mixed_refs >= 0)
         x4->params.analyse.b_mixed_references = x4->mixed_refs;
     if (x4->b_bias != INT_MIN)
         x4->params.i_bframe_bias              = x4->b_bias;
     if (x4->cplxblur >= 0)
         x4->params.rc.f_complexity_blur = x4->cplxblur;

 
     x4->params.i_bframe          = avctx->max_b_frames;
     /* cabac is not included in AVS JiZhun Profile */
     x4->params.b_cabac           = 0;
 
     x4->params.i_bframe_adaptive = avctx->b_frame_strategy;
 
     avctx->has_b_frames          = !!avctx->max_b_frames;
 
     /* AVS doesn't allow B picture as reference */
     /* The max allowed reference frame number of B is 2 */
     x4->params.i_keyint_min      = avctx->keyint_min;
     if (x4->params.i_keyint_min > x4->params.i_keyint_max)
         x4->params.i_keyint_min = x4->params.i_keyint_max;
 
     x4->params.i_scenecut_threshold        = avctx->scenechange_threshold;
 
    // x4->params.b_deblocking_filter       = avctx->flags & CODEC_FLAG_LOOP_FILTER;
 
     x4->params.rc.i_qp_min                 = avctx->qmin;
     x4->params.rc.i_qp_max                 = avctx->qmax;
     x4->params.rc.i_qp_step                = avctx->max_qdiff;
 
     x4->params.rc.f_qcompress       = avctx->qcompress; /* 0.0 => cbr, 1.0 => constant qp */
     x4->params.rc.f_qblur           = avctx->qblur;     /* temporally blur quants */
 
     x4->params.i_frame_reference    = avctx->refs;
 
     x4->params.i_width              = avctx->width;
     x4->params.i_height             = avctx->height;
     x4->params.vui.i_sar_width      = avctx->sample_aspect_ratio.num;
     x4->params.vui.i_sar_height     = avctx->sample_aspect_ratio.den;
     /* This is only used for counting the fps */
     x4->params.i_fps_num            = avctx->time_base.den;
     x4->params.i_fps_den            = avctx->time_base.num;
     x4->params.analyse.inter        = XAVS_ANALYSE_I8x8 |XAVS_ANALYSE_PSUB16x16| XAVS_ANALYSE_BSUB16x16;
 
     switch (avctx->me_method) {
          case  ME_EPZS:
                x4->params.analyse.i_me_method = XAVS_ME_DIA;
                break;
          case  ME_HEX:
                x4->params.analyse.i_me_method = XAVS_ME_HEX;
                break;
          case  ME_UMH:
                x4->params.analyse.i_me_method = XAVS_ME_UMH;
                break;
          case  ME_FULL:
                x4->params.analyse.i_me_method = XAVS_ME_ESA;
                break;
          case  ME_TESA:
                x4->params.analyse.i_me_method = XAVS_ME_TESA;
                break;
          default:
                x4->params.analyse.i_me_method = XAVS_ME_HEX;
     }
 
     x4->params.analyse.i_me_range = avctx->me_range;
     x4->params.analyse.i_subpel_refine    = avctx->me_subpel_quality;
 
     x4->params.analyse.b_chroma_me        = avctx->me_cmp & FF_CMP_CHROMA;
     /* AVS P2 only enables 8x8 transform */
     x4->params.analyse.b_transform_8x8    = 1; //avctx->flags2 & CODEC_FLAG2_8X8DCT;
 
     x4->params.analyse.i_trellis          = avctx->trellis;
     x4->params.analyse.i_noise_reduction  = avctx->noise_reduction;
 
     if (avctx->level > 0)
         x4->params.i_level_idc = avctx->level;
 
     x4->params.rc.f_rate_tolerance =
         (float)avctx->bit_rate_tolerance/avctx->bit_rate;
 
     if ((avctx->rc_buffer_size) &&
         (avctx->rc_initial_buffer_occupancy <= avctx->rc_buffer_size)) {
         x4->params.rc.f_vbv_buffer_init =
             (float)avctx->rc_initial_buffer_occupancy / avctx->rc_buffer_size;
     } else
         x4->params.rc.f_vbv_buffer_init = 0.9;
 
     /* TAG:do we have MB tree RC method */
     /* what is the RC method we are now using? Default NO */
     x4->params.rc.f_ip_factor             = 1 / fabs(avctx->i_quant_factor);
     x4->params.rc.f_pb_factor             = avctx->b_quant_factor;
     x4->params.analyse.i_chroma_qp_offset = avctx->chromaoffset;
 
     x4->params.analyse.b_psnr = avctx->flags & CODEC_FLAG_PSNR;
     x4->params.i_log_level    = XAVS_LOG_DEBUG;
     x4->params.i_threads      = avctx->thread_count;
     x4->params.b_interlaced   = avctx->flags & CODEC_FLAG_INTERLACED_DCT;
 
     if (avctx->flags & CODEC_FLAG_GLOBAL_HEADER)
         x4->params.b_repeat_headers = 0;
 
     x4->enc = xavs_encoder_open(&x4->params);
     if (!x4->enc)
         return -1;
 

     if (!(x4->pts_buffer = av_mallocz((avctx->max_b_frames+1) * sizeof(*x4->pts_buffer))))
         return AVERROR(ENOMEM);
 

     avctx->coded_frame = &x4->out_pic;
     /* TAG: Do we have GLOBAL HEADER in AVS */
     /* We Have PPS and SPS in AVS */
     if (avctx->flags & CODEC_FLAG_GLOBAL_HEADER) {
         xavs_nal_t *nal;

         int nnal, s, i, size;
         uint8_t *p;

 
         s = xavs_encoder_headers(x4->enc, &nal, &nnal);
 

         avctx->extradata = p = av_malloc(s);
         for (i = 0; i < nnal; i++) {
             /* Don't put the SEI in extradata. */
             if (nal[i].i_type == NAL_SEI) {
                 x4->sei = av_malloc( 5 + nal[i].i_payload * 4 / 3 );
                 if (xavs_nal_encode(x4->sei, &x4->sei_size, 1, nal + i) < 0)
                     return -1;
 
                 continue;
             }
             size = xavs_nal_encode(p, &s, 1, nal + i);
             if (size < 0)
                 return -1;
             p += size;
         }
         avctx->extradata_size = p - avctx->extradata;

     }
     return 0;
 }
 

 #define OFFSET(x) offsetof(XavsContext, x)
 #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
 static const AVOption options[] = {

     { "crf",           "Select the quality for constant quality mode",    OFFSET(crf),           AV_OPT_TYPE_FLOAT,  {.dbl = -1 }, -1, FLT_MAX, VE },

     { "qp",            "Constant quantization parameter rate control method",OFFSET(cqp),        AV_OPT_TYPE_INT,    {.i64 = -1 }, -1, INT_MAX, VE },
     { "b-bias",        "Influences how often B-frames are used",          OFFSET(b_bias),        AV_OPT_TYPE_INT,    {.i64 = INT_MIN}, INT_MIN, INT_MAX, VE },

     { "cplxblur",      "Reduce fluctuations in QP (before curve compression)", OFFSET(cplxblur), AV_OPT_TYPE_FLOAT,  {.dbl = -1 }, -1, FLT_MAX, VE},

     { "direct-pred",   "Direct MV prediction mode",                       OFFSET(direct_pred),   AV_OPT_TYPE_INT,    {.i64 = -1 }, -1, INT_MAX, VE, "direct-pred" },

     { "none",          NULL,      0,    AV_OPT_TYPE_CONST, { .i64 = XAVS_DIRECT_PRED_NONE },     0, 0, VE, "direct-pred" },
     { "spatial",       NULL,      0,    AV_OPT_TYPE_CONST, { .i64 = XAVS_DIRECT_PRED_SPATIAL },  0, 0, VE, "direct-pred" },
     { "temporal",      NULL,      0,    AV_OPT_TYPE_CONST, { .i64 = XAVS_DIRECT_PRED_TEMPORAL }, 0, 0, VE, "direct-pred" },
     { "auto",          NULL,      0,    AV_OPT_TYPE_CONST, { .i64 = XAVS_DIRECT_PRED_AUTO },     0, 0, VE, "direct-pred" },

     { "aud",           "Use access unit delimiters.",                     OFFSET(aud),           AV_OPT_TYPE_INT,    {.i64 = -1 }, -1, 1, VE},
     { "mbtree",        "Use macroblock tree ratecontrol.",                OFFSET(mbtree),        AV_OPT_TYPE_INT,    {.i64 = -1 }, -1, 1, VE},
     { "mixed-refs",    "One reference per partition, as opposed to one reference per macroblock", OFFSET(mixed_refs), AV_OPT_TYPE_INT, {.i64 = -1}, -1, 1, VE },
     { "fast-pskip",    NULL,                                              OFFSET(fast_pskip),    AV_OPT_TYPE_INT,    {.i64 = -1 }, -1, 1, VE},

     { NULL },
 };
 
 static const AVClass class = {
     .class_name = "libxavs",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
 static const AVCodecDefault xavs_defaults[] = {
     { "b",                "0" },
     { NULL },
 };
 

 AVCodec ff_libxavs_encoder = {

     .name           = "libxavs",

     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_CAVS,

     .priv_data_size = sizeof(XavsContext),
     .init           = XAVS_init,

     .encode2        = XAVS_frame,

     .close          = XAVS_close,

     .capabilities   = CODEC_CAP_DELAY | CODEC_CAP_AUTO_THREADS,

     .pix_fmts       = (const enum AVPixelFormat[]) { AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE },

     .long_name      = NULL_IF_CONFIG_SMALL("libxavs Chinese AVS (Audio Video Standard)"),

     .priv_class     = &class,
     .defaults       = xavs_defaults,

 };