/*
  * Copyright (C) 2015 Pedro Arthur <bygrandao@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 "swscale_internal.h"
 

 typedef struct VScalerContext
 {
     uint16_t *filter[2];
     int32_t  *filter_pos;
     int filter_size;
     int isMMX;
     void *pfn;

     yuv2packedX_fn yuv2packedX;

 } VScalerContext;
 
 

 static int lum_planar_vscale(SwsContext *c, SwsFilterDescriptor *desc, int sliceY, int sliceH)
 {
     VScalerContext *inst = desc->instance;
     int dstW = desc->dst->width;
 
     int first = FFMAX(1-inst->filter_size, inst->filter_pos[sliceY]);
     int sp = first - desc->src->plane[0].sliceY;
     int dp = sliceY - desc->dst->plane[0].sliceY;
     uint8_t **src = desc->src->plane[0].line + sp;
     uint8_t **dst = desc->dst->plane[0].line + dp;
     uint16_t *filter = inst->filter[0] + (inst->isMMX ? 0 : sliceY * inst->filter_size);
 
     if (inst->filter_size == 1)
         ((yuv2planar1_fn)inst->pfn)((const int16_t*)src[0], dst[0], dstW, c->lumDither8, 0);
     else
         ((yuv2planarX_fn)inst->pfn)(filter, inst->filter_size, (const int16_t**)src, dst[0], dstW, c->lumDither8, 0);
 
     if (desc->alpha) {
         int sp = first - desc->src->plane[3].sliceY;
         int dp = sliceY - desc->dst->plane[3].sliceY;
         uint8_t **src = desc->src->plane[3].line + sp;
         uint8_t **dst = desc->dst->plane[3].line + dp;
         uint16_t *filter = inst->filter[1] + (inst->isMMX ? 0 : sliceY * inst->filter_size);
 
         if (inst->filter_size == 1)
             ((yuv2planar1_fn)inst->pfn)((const int16_t*)src[0], dst[0], dstW, c->lumDither8, 0);
         else
             ((yuv2planarX_fn)inst->pfn)(filter, inst->filter_size, (const int16_t**)src, dst[0], dstW, c->lumDither8, 0);
     }
 
     return 1;
 }
 
 static int chr_planar_vscale(SwsContext *c, SwsFilterDescriptor *desc, int sliceY, int sliceH)
 {
     const int chrSkipMask = (1 << desc->dst->v_chr_sub_sample) - 1;
     if (sliceY & chrSkipMask)
         return 0;
     else {
         VScalerContext *inst = desc->instance;

         int dstW = AV_CEIL_RSHIFT(desc->dst->width, desc->dst->h_chr_sub_sample);

         int chrSliceY = sliceY >> desc->dst->v_chr_sub_sample;
 
         int first = FFMAX(1-inst->filter_size, inst->filter_pos[chrSliceY]);
         int sp1 = first - desc->src->plane[1].sliceY;
         int sp2 = first - desc->src->plane[2].sliceY;
         int dp1 = chrSliceY - desc->dst->plane[1].sliceY;
         int dp2 = chrSliceY - desc->dst->plane[2].sliceY;
         uint8_t **src1 = desc->src->plane[1].line + sp1;
         uint8_t **src2 = desc->src->plane[2].line + sp2;
         uint8_t **dst1 = desc->dst->plane[1].line + dp1;
         uint8_t **dst2 = desc->dst->plane[2].line + dp2;
         uint16_t *filter = inst->filter[0] + (inst->isMMX ? 0 : chrSliceY * inst->filter_size);
 
         if (c->yuv2nv12cX) {
             ((yuv2interleavedX_fn)inst->pfn)(c, filter, inst->filter_size, (const int16_t**)src1, (const int16_t**)src2, dst1[0], dstW);
         } else if (inst->filter_size == 1) {
             ((yuv2planar1_fn)inst->pfn)((const int16_t*)src1[0], dst1[0], dstW, c->chrDither8, 0);
             ((yuv2planar1_fn)inst->pfn)((const int16_t*)src2[0], dst2[0], dstW, c->chrDither8, 3);
         } else {
             ((yuv2planarX_fn)inst->pfn)(filter, inst->filter_size, (const int16_t**)src1, dst1[0], dstW, c->chrDither8, 0);
             ((yuv2planarX_fn)inst->pfn)(filter, inst->filter_size, (const int16_t**)src2, dst2[0], dstW, c->chrDither8, inst->isMMX ? (c->uv_offx2 >> 1) : 3);
         }
     }
 
     return 1;
 }
 
 static int packed_vscale(SwsContext *c, SwsFilterDescriptor *desc, int sliceY, int sliceH)
 {
     VScalerContext *inst = desc->instance;
     int dstW = desc->dst->width;
     int chrSliceY = sliceY >> desc->dst->v_chr_sub_sample;
 
     int lum_fsize = inst[0].filter_size;
     int chr_fsize = inst[1].filter_size;
     uint16_t *lum_filter = inst[0].filter[0];
     uint16_t *chr_filter = inst[1].filter[0];
 

     int firstLum = FFMAX(1-lum_fsize, inst[0].filter_pos[   sliceY]);

     int firstChr = FFMAX(1-chr_fsize, inst[1].filter_pos[chrSliceY]);
 
     int sp0 = firstLum - desc->src->plane[0].sliceY;
     int sp1 = firstChr - desc->src->plane[1].sliceY;
     int sp2 = firstChr - desc->src->plane[2].sliceY;
     int sp3 = firstLum - desc->src->plane[3].sliceY;
     int dp = sliceY - desc->dst->plane[0].sliceY;
     uint8_t **src0 = desc->src->plane[0].line + sp0;
     uint8_t **src1 = desc->src->plane[1].line + sp1;
     uint8_t **src2 = desc->src->plane[2].line + sp2;
     uint8_t **src3 = desc->alpha ? desc->src->plane[3].line + sp3 : NULL;
     uint8_t **dst = desc->dst->plane[0].line + dp;
 
 

     if (c->yuv2packed1 && lum_fsize == 1 && chr_fsize == 1) { // unscaled RGB
         ((yuv2packed1_fn)inst->pfn)(c, (const int16_t*)*src0, (const int16_t**)src1, (const int16_t**)src2,
                                     (const int16_t*)(desc->alpha ? *src3 : NULL),  *dst, dstW, 0, sliceY);
     } else if (c->yuv2packed1 && lum_fsize == 1 && chr_fsize == 2 &&

                chr_filter[2 * chrSliceY + 1] + chr_filter[2 * chrSliceY] == 4096 &&
                chr_filter[2 * chrSliceY + 1] <= 4096U) { // unscaled RGB
         int chrAlpha = chr_filter[2 * chrSliceY + 1];

         ((yuv2packed1_fn)inst->pfn)(c, (const int16_t*)*src0, (const int16_t**)src1, (const int16_t**)src2,
                                     (const int16_t*)(desc->alpha ? *src3 : NULL),  *dst, dstW, chrAlpha, sliceY);
     } else if (c->yuv2packed2 && lum_fsize == 2 && chr_fsize == 2 &&
                lum_filter[2 * sliceY + 1] + lum_filter[2 * sliceY] == 4096 &&
                lum_filter[2 * sliceY + 1] <= 4096U &&
                chr_filter[2 * chrSliceY + 1] + chr_filter[2 * chrSliceY] == 4096 &&
                chr_filter[2 * chrSliceY + 1] <= 4096U
     ) { // bilinear upscale RGB

         int lumAlpha = lum_filter[2 * sliceY + 1];

         int chrAlpha = chr_filter[2 * chrSliceY + 1];

         c->lumMmxFilter[2] =
         c->lumMmxFilter[3] = lum_filter[2 * sliceY]    * 0x10001;
         c->chrMmxFilter[2] =
         c->chrMmxFilter[3] = chr_filter[2 * chrSliceY] * 0x10001;
         ((yuv2packed2_fn)inst->pfn)(c, (const int16_t**)src0, (const int16_t**)src1, (const int16_t**)src2, (const int16_t**)src3,
                     *dst, dstW, lumAlpha, chrAlpha, sliceY);
     } else { // general RGB

         if ((c->yuv2packed1 && lum_fsize == 1 && chr_fsize == 2) ||
             (c->yuv2packed2 && lum_fsize == 2 && chr_fsize == 2)) {
             if (!c->warned_unuseable_bilinear)
                 av_log(c, AV_LOG_INFO, "Optimized 2 tap filter code cannot be used\n");
             c->warned_unuseable_bilinear = 1;
         }
 
         inst->yuv2packedX(c, lum_filter + sliceY * lum_fsize,

                     (const int16_t**)src0, lum_fsize, chr_filter + chrSliceY * chr_fsize,

                     (const int16_t**)src1, (const int16_t**)src2, chr_fsize, (const int16_t**)src3, *dst, dstW, sliceY);
     }
     return 1;
 }
 
 static int any_vscale(SwsContext *c, SwsFilterDescriptor *desc, int sliceY, int sliceH)
 {
     VScalerContext *inst = desc->instance;
     int dstW = desc->dst->width;
     int chrSliceY = sliceY >> desc->dst->v_chr_sub_sample;
 
     int lum_fsize = inst[0].filter_size;
     int chr_fsize = inst[1].filter_size;
     uint16_t *lum_filter = inst[0].filter[0];
     uint16_t *chr_filter = inst[1].filter[0];
 

     int firstLum = FFMAX(1-lum_fsize, inst[0].filter_pos[   sliceY]);

     int firstChr = FFMAX(1-chr_fsize, inst[1].filter_pos[chrSliceY]);
 
     int sp0 = firstLum - desc->src->plane[0].sliceY;
     int sp1 = firstChr - desc->src->plane[1].sliceY;
     int sp2 = firstChr - desc->src->plane[2].sliceY;
     int sp3 = firstLum - desc->src->plane[3].sliceY;
     int dp0 = sliceY - desc->dst->plane[0].sliceY;
     int dp1 = chrSliceY - desc->dst->plane[1].sliceY;
     int dp2 = chrSliceY - desc->dst->plane[2].sliceY;
     int dp3 = sliceY - desc->dst->plane[3].sliceY;
 
     uint8_t **src0 = desc->src->plane[0].line + sp0;
     uint8_t **src1 = desc->src->plane[1].line + sp1;
     uint8_t **src2 = desc->src->plane[2].line + sp2;
     uint8_t **src3 = desc->alpha ? desc->src->plane[3].line + sp3 : NULL;
     uint8_t *dst[4] = { desc->dst->plane[0].line[dp0],
                         desc->dst->plane[1].line[dp1],
                         desc->dst->plane[2].line[dp2],
                         desc->alpha ? desc->dst->plane[3].line[dp3] : NULL };
 
     av_assert1(!c->yuv2packed1 && !c->yuv2packed2);
     ((yuv2anyX_fn)inst->pfn)(c, lum_filter + sliceY * lum_fsize,
              (const int16_t**)src0, lum_fsize, chr_filter + sliceY * chr_fsize,
              (const int16_t**)src1, (const int16_t**)src2, chr_fsize, (const int16_t**)src3, dst, dstW, sliceY);
 
     return 1;
 
 }
 
 int ff_init_vscale(SwsContext *c, SwsFilterDescriptor *desc, SwsSlice *src, SwsSlice *dst)
 {
     VScalerContext *lumCtx = NULL;
     VScalerContext *chrCtx = NULL;
 
     if (isPlanarYUV(c->dstFormat) || (isGray(c->dstFormat) && !isALPHA(c->dstFormat))) {
         lumCtx = av_mallocz(sizeof(VScalerContext));
         if (!lumCtx)
             return AVERROR(ENOMEM);
 
 
         desc[0].process = lum_planar_vscale;
         desc[0].instance = lumCtx;
         desc[0].src = src;
         desc[0].dst = dst;

         desc[0].alpha = c->needAlpha;

 
         if (!isGray(c->dstFormat)) {
             chrCtx = av_mallocz(sizeof(VScalerContext));
             if (!chrCtx)
                 return AVERROR(ENOMEM);
             desc[1].process = chr_planar_vscale;
             desc[1].instance = chrCtx;
             desc[1].src = src;
             desc[1].dst = dst;
         }
     } else {
         lumCtx = av_mallocz_array(sizeof(VScalerContext), 2);
         if (!lumCtx)
             return AVERROR(ENOMEM);
         chrCtx = &lumCtx[1];
 
         desc[0].process = c->yuv2packedX ? packed_vscale : any_vscale;
         desc[0].instance = lumCtx;
         desc[0].src = src;
         desc[0].dst = dst;

         desc[0].alpha = c->needAlpha;

     }
 
     ff_init_vscale_pfn(c, c->yuv2plane1, c->yuv2planeX, c->yuv2nv12cX,
         c->yuv2packed1, c->yuv2packed2, c->yuv2packedX, c->yuv2anyX, c->use_mmx_vfilter);
     return 0;
 }
 
 void ff_init_vscale_pfn(SwsContext *c,
     yuv2planar1_fn yuv2plane1,
     yuv2planarX_fn yuv2planeX,
     yuv2interleavedX_fn yuv2nv12cX,
     yuv2packed1_fn yuv2packed1,
     yuv2packed2_fn yuv2packed2,
     yuv2packedX_fn yuv2packedX,
     yuv2anyX_fn yuv2anyX, int use_mmx)
 {
     VScalerContext *lumCtx = NULL;
     VScalerContext *chrCtx = NULL;

     int idx = c->numDesc - (c->is_internal_gamma ? 2 : 1); //FIXME avoid hardcoding indexes

 
     if (isPlanarYUV(c->dstFormat) || (isGray(c->dstFormat) && !isALPHA(c->dstFormat))) {
         if (!isGray(c->dstFormat)) {
             chrCtx = c->desc[idx].instance;
 
             chrCtx->filter[0] = use_mmx ? (int16_t*)c->chrMmxFilter : c->vChrFilter;
             chrCtx->filter_size = c->vChrFilterSize;
             chrCtx->filter_pos = c->vChrFilterPos;
             chrCtx->isMMX = use_mmx;
 
             --idx;
             if (yuv2nv12cX)               chrCtx->pfn = yuv2nv12cX;
             else if (c->vChrFilterSize == 1) chrCtx->pfn = yuv2plane1;
             else                             chrCtx->pfn = yuv2planeX;
         }
 
         lumCtx = c->desc[idx].instance;
 
         lumCtx->filter[0] = use_mmx ? (int16_t*)c->lumMmxFilter : c->vLumFilter;
         lumCtx->filter[1] = use_mmx ? (int16_t*)c->alpMmxFilter : c->vLumFilter;
         lumCtx->filter_size = c->vLumFilterSize;
         lumCtx->filter_pos = c->vLumFilterPos;
         lumCtx->isMMX = use_mmx;
 
         if (c->vLumFilterSize == 1) lumCtx->pfn = yuv2plane1;
         else                        lumCtx->pfn = yuv2planeX;
 
     } else {
         lumCtx = c->desc[idx].instance;
         chrCtx = &lumCtx[1];
 
         lumCtx->filter[0] = c->vLumFilter;
         lumCtx->filter_size = c->vLumFilterSize;
         lumCtx->filter_pos = c->vLumFilterPos;
 
         chrCtx->filter[0] = c->vChrFilter;
         chrCtx->filter_size = c->vChrFilterSize;
         chrCtx->filter_pos = c->vChrFilterPos;
 
         lumCtx->isMMX = use_mmx;
         chrCtx->isMMX = use_mmx;
 
         if (yuv2packedX) {
             if (c->yuv2packed1 && c->vLumFilterSize == 1 && c->vChrFilterSize <= 2)
                 lumCtx->pfn = yuv2packed1;
             else if (c->yuv2packed2 && c->vLumFilterSize == 2 && c->vChrFilterSize == 2)
                 lumCtx->pfn = yuv2packed2;

             lumCtx->yuv2packedX = yuv2packedX;

         } else
             lumCtx->pfn = yuv2anyX;
     }
 }