/*
  * 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"
 
 static void free_lines(SwsSlice *s)
 {
     int i;
     for (i = 0; i < 2; ++i) {
         int n = s->plane[i].available_lines;
         int j;
         for (j = 0; j < n; ++j) {
             av_freep(&s->plane[i].line[j]);
             if (s->is_ring)
                s->plane[i].line[j+n] = NULL;
         }
     }
 
     for (i = 0; i < 4; ++i)
         memset(s->plane[i].line, 0, sizeof(uint8_t*) * s->plane[i].available_lines * (s->is_ring ? 3 : 1));
     s->should_free_lines = 0;
 }
 
 /*

  slice lines contains extra bytes for vectorial code thus @size

  is the allocated memory size and @width is the number of pixels
 */
 static int alloc_lines(SwsSlice *s, int size, int width)
 {
     int i;
     int idx[2] = {3, 2};
 
     s->should_free_lines = 1;
     s->width = width;
 
     for (i = 0; i < 2; ++i) {
         int n = s->plane[i].available_lines;
         int j;
         int ii = idx[i];
 
         av_assert0(n == s->plane[ii].available_lines);
         for (j = 0; j < n; ++j) {
             // chroma plane line U and V are expected to be contiguous in memory
             // by mmx vertical scaler code
             s->plane[i].line[j] = av_malloc(size * 2 + 32);
             if (!s->plane[i].line[j]) {
                 free_lines(s);
                 return AVERROR(ENOMEM);
             }
             s->plane[ii].line[j] = s->plane[i].line[j] + size + 16;
             if (s->is_ring) {
                s->plane[i].line[j+n] = s->plane[i].line[j];
                s->plane[ii].line[j+n] = s->plane[ii].line[j];
             }
         }
     }
 
     return 0;
 }
 
 static int alloc_slice(SwsSlice *s, enum AVPixelFormat fmt, int lumLines, int chrLines, int h_sub_sample, int v_sub_sample, int ring)
 {
     int i;
     int size[4] = { lumLines,
                     chrLines,
                     chrLines,
                     lumLines };
 
     s->h_chr_sub_sample = h_sub_sample;
     s->v_chr_sub_sample = v_sub_sample;
     s->fmt = fmt;
     s->is_ring = ring;
     s->should_free_lines = 0;
 
     for (i = 0; i < 4; ++i) {
         int n = size[i] * ( ring == 0 ? 1 : 3);
         s->plane[i].line = av_mallocz_array(sizeof(uint8_t*), n);
         if (!s->plane[i].line)
             return AVERROR(ENOMEM);
 
         s->plane[i].tmp = ring ? s->plane[i].line + size[i] * 2 : NULL;
         s->plane[i].available_lines = size[i];
         s->plane[i].sliceY = 0;
         s->plane[i].sliceH = 0;
     }
     return 0;
 }
 
 static void free_slice(SwsSlice *s)
 {
     int i;
     if (s) {
         if (s->should_free_lines)
             free_lines(s);
         for (i = 0; i < 4; ++i) {
             av_freep(&s->plane[i].line);
             s->plane[i].tmp = NULL;
         }
     }
 }
 
 int ff_rotate_slice(SwsSlice *s, int lum, int chr)
 {
     int i;
     if (lum) {
         for (i = 0; i < 4; i+=3) {
             int n = s->plane[i].available_lines;
             int l = lum - s->plane[i].sliceY;
 
             if (l >= n * 2) {
                 s->plane[i].sliceY += n;
                 s->plane[i].sliceH -= n;
             }
         }
     }
     if (chr) {
         for (i = 1; i < 3; ++i) {
             int n = s->plane[i].available_lines;
             int l = chr - s->plane[i].sliceY;
 
             if (l >= n * 2) {
                 s->plane[i].sliceY += n;
                 s->plane[i].sliceH -= n;
             }
         }
     }
     return 0;
 }
 

 int ff_init_slice_from_src(SwsSlice * s, uint8_t *src[4], int stride[4], int srcW, int lumY, int lumH, int chrY, int chrH, int relative)

 {
     int i = 0;
 
     const int start[4] = {lumY,

                           chrY,
                           chrY,
                           lumY};

 
     const int end[4] = {lumY +lumH,
                         chrY + chrH,
                         chrY + chrH,
                         lumY + lumH};
 

     uint8_t *const src_[4] = {src[0] + (relative ? 0 : start[0]) * stride[0],

                               src[1] + (relative ? 0 : start[1]) * stride[1],
                               src[2] + (relative ? 0 : start[2]) * stride[2],
                               src[3] + (relative ? 0 : start[3]) * stride[3]};

     s->width = srcW;
 
     for (i = 0; i < 4; ++i) {
         int j;

         int first = s->plane[i].sliceY;
         int n = s->plane[i].available_lines;
         int lines = end[i] - start[i];
         int tot_lines = end[i] - first;

         if (start[i] >= first && n >= tot_lines) {
             s->plane[i].sliceH = FFMAX(tot_lines, s->plane[i].sliceH);
             for (j = 0; j < lines; j+= 1)
                 s->plane[i].line[start[i] - first + j] = src_[i] +  j * stride[i];

         } else {
             s->plane[i].sliceY = start[i];

             lines = lines > n ? n : lines;
             s->plane[i].sliceH = lines;
             for (j = 0; j < lines; j+= 1)
                 s->plane[i].line[j] = src_[i] +  j * stride[i];

         }
 
     }
 
     return 0;
 }
 
 static void fill_ones(SwsSlice *s, int n, int is16bit)
 {
     int i;
     for (i = 0; i < 4; ++i) {
         int j;
         int size = s->plane[i].available_lines;
         for (j = 0; j < size; ++j) {
             int k;
             int end = is16bit ? n>>1: n;
             // fill also one extra element
             end += 1;
             if (is16bit)
                 for (k = 0; k < end; ++k)
                     ((int32_t*)(s->plane[i].line[j]))[k] = 1<<18;
             else
                 for (k = 0; k < end; ++k)
                     ((int16_t*)(s->plane[i].line[j]))[k] = 1<<14;
         }
     }
 }
 

 /*
  Calculates the minimum ring buffer size, it should be able to store vFilterSize
  more n lines where n is the max difference between each adjacent slice which
  outputs a line.
  The n lines are needed only when there is not enough src lines to output a single
  dst line, then we should buffer these lines to process them on the next call to scale.
 */
 static void get_min_buffer_size(SwsContext *c, int *out_lum_size, int *out_chr_size)
 {
     int lumY;
     int dstH = c->dstH;
     int chrDstH = c->chrDstH;
     int *lumFilterPos = c->vLumFilterPos;
     int *chrFilterPos = c->vChrFilterPos;
     int lumFilterSize = c->vLumFilterSize;
     int chrFilterSize = c->vChrFilterSize;
     int chrSubSample = c->chrSrcVSubSample;
 
     *out_lum_size = lumFilterSize;
     *out_chr_size = chrFilterSize;
 
     for (lumY = 0; lumY < dstH; lumY++) {
         int chrY      = (int64_t)lumY * chrDstH / dstH;
         int nextSlice = FFMAX(lumFilterPos[lumY] + lumFilterSize - 1,
                               ((chrFilterPos[chrY] + chrFilterSize - 1)
                                << chrSubSample));
 
         nextSlice >>= chrSubSample;
         nextSlice <<= chrSubSample;
         (*out_lum_size) = FFMAX((*out_lum_size), nextSlice - lumFilterPos[lumY]);
         (*out_chr_size) = FFMAX((*out_chr_size), (nextSlice >> chrSubSample) - chrFilterPos[chrY]);
     }
 }
 
 
 

 int ff_init_filters(SwsContext * c)
 {
     int i;
     int index;
     int num_ydesc;
     int num_cdesc;

     int num_vdesc = isPlanarYUV(c->dstFormat) && !isGray(c->dstFormat) ? 2 : 1;

     int need_lum_conv = c->lumToYV12 || c->readLumPlanar || c->alpToYV12 || c->readAlpPlanar;
     int need_chr_conv = c->chrToYV12 || c->readChrPlanar;

     int need_gamma = c->is_internal_gamma;

     int srcIdx, dstIdx;
     int dst_stride = FFALIGN(c->dstW * sizeof(int16_t) + 66, 16);
 
     uint32_t * pal = usePal(c->srcFormat) ? c->pal_yuv : (uint32_t*)c->input_rgb2yuv_table;
     int res = 0;
 

     int lumBufSize;
     int chrBufSize;
 
     get_min_buffer_size(c, &lumBufSize, &chrBufSize);
     lumBufSize = FFMAX(lumBufSize, c->vLumFilterSize + MAX_LINES_AHEAD);
     chrBufSize = FFMAX(chrBufSize, c->vChrFilterSize + MAX_LINES_AHEAD);
 

     if (c->dstBpc == 16)
         dst_stride <<= 1;
 
     num_ydesc = need_lum_conv ? 2 : 1;
     num_cdesc = need_chr_conv ? 2 : 1;
 

     c->numSlice = FFMAX(num_ydesc, num_cdesc) + 2;

     c->numDesc = num_ydesc + num_cdesc + num_vdesc + (need_gamma ? 2 : 0);
     c->descIndex[0] = num_ydesc + (need_gamma ? 1 : 0);
     c->descIndex[1] = num_ydesc + num_cdesc + (need_gamma ? 1 : 0);

 
 
 
     c->desc = av_mallocz_array(sizeof(SwsFilterDescriptor), c->numDesc);
     if (!c->desc)
         return AVERROR(ENOMEM);
     c->slice = av_mallocz_array(sizeof(SwsSlice), c->numSlice);
 
 
     res = alloc_slice(&c->slice[0], c->srcFormat, c->srcH, c->chrSrcH, c->chrSrcHSubSample, c->chrSrcVSubSample, 0);
     if (res < 0) goto cleanup;

     for (i = 1; i < c->numSlice-2; ++i) {

         res = alloc_slice(&c->slice[i], c->srcFormat, lumBufSize, chrBufSize, c->chrSrcHSubSample, c->chrSrcVSubSample, 0);

         if (res < 0) goto cleanup;
         res = alloc_lines(&c->slice[i], FFALIGN(c->srcW*2+78, 16), c->srcW);
         if (res < 0) goto cleanup;
     }

     // horizontal scaler output

     res = alloc_slice(&c->slice[i], c->srcFormat, lumBufSize, chrBufSize, c->chrDstHSubSample, c->chrDstVSubSample, 1);

     if (res < 0) goto cleanup;
     res = alloc_lines(&c->slice[i], dst_stride, c->dstW);
     if (res < 0) goto cleanup;
 
     fill_ones(&c->slice[i], dst_stride>>1, c->dstBpc == 16);
 

     // vertical scaler output
     ++i;
     res = alloc_slice(&c->slice[i], c->dstFormat, c->dstH, c->chrDstH, c->chrDstHSubSample, c->chrDstVSubSample, 0);
     if (res < 0) goto cleanup;
 

     index = 0;
     srcIdx = 0;
     dstIdx = 1;
 

     if (need_gamma) {
         res = ff_init_gamma_convert(c->desc + index, c->slice + srcIdx, c->inv_gamma);
         if (res < 0) goto cleanup;
         ++index;
     }
 

     if (need_lum_conv) {

         res = ff_init_desc_fmt_convert(&c->desc[index], &c->slice[srcIdx], &c->slice[dstIdx], pal);
         if (res < 0) goto cleanup;

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

         ++index;
         srcIdx = dstIdx;
     }
 
 
     dstIdx = FFMAX(num_ydesc, num_cdesc);

     res = ff_init_desc_hscale(&c->desc[index], &c->slice[srcIdx], &c->slice[dstIdx], c->hLumFilter, c->hLumFilterPos, c->hLumFilterSize, c->lumXInc);
     if (res < 0) goto cleanup;

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

 
 
     ++index;
     {
         srcIdx = 0;
         dstIdx = 1;
         if (need_chr_conv) {

             res = ff_init_desc_cfmt_convert(&c->desc[index], &c->slice[srcIdx], &c->slice[dstIdx], pal);
             if (res < 0) goto cleanup;

             ++index;
             srcIdx = dstIdx;
         }
 
         dstIdx = FFMAX(num_ydesc, num_cdesc);
         if (c->needs_hcscale)

             res = ff_init_desc_chscale(&c->desc[index], &c->slice[srcIdx], &c->slice[dstIdx], c->hChrFilter, c->hChrFilterPos, c->hChrFilterSize, c->chrXInc);

         else

             res = ff_init_desc_no_chr(&c->desc[index], &c->slice[srcIdx], &c->slice[dstIdx]);
         if (res < 0) goto cleanup;

     }
 

     ++index;
     {
         srcIdx = c->numSlice - 2;
         dstIdx = c->numSlice - 1;

         res = ff_init_vscale(c, c->desc + index, c->slice + srcIdx, c->slice + dstIdx);
         if (res < 0) goto cleanup;

     }
 

     ++index;
     if (need_gamma) {
         res = ff_init_gamma_convert(c->desc + index, c->slice + dstIdx, c->gamma);
         if (res < 0) goto cleanup;
     }
 

     return 0;
 
 cleanup:
     ff_free_filters(c);
     return res;
 }
 
 int ff_free_filters(SwsContext *c)
 {
     int i;
     if (c->desc) {
         for (i = 0; i < c->numDesc; ++i)
             av_freep(&c->desc[i].instance);
         av_freep(&c->desc);
     }
 
     if (c->slice) {
         for (i = 0; i < c->numSlice; ++i)
             free_slice(&c->slice[i]);
         av_freep(&c->slice);
     }
     return 0;
 }