/*
  * Copyright (c) 2016 Floris Sluiter
  *
  * 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
  */
 
 /**
  * @file
  * Pixel remap filter
  * This filter copies pixel by pixel a source frame to a target frame.
  * It remaps the pixels to a new x,y destination based on two files ymap/xmap.
  * Map files are passed as a parameter and are in PGM format (P2 or P5),
  * where the values are y(rows)/x(cols) coordinates of the source_frame.
  * The *target* frame dimension is based on mapfile dimensions: specified in the
  * header of the mapfile and reflected in the number of datavalues.
  * Dimensions of ymap and xmap must be equal. Datavalues must be positive or zero.
  * Any datavalue in the ymap or xmap which value is higher
  * then the *source* frame height or width is silently ignored, leaving a
  * blank/chromakey pixel. This can safely be used as a feature to create overlays.
  *
  * Algorithm digest:
  * Target_frame[y][x] = Source_frame[ ymap[y][x] ][ [xmap[y][x] ];
  */
 
 #include "libavutil/imgutils.h"
 #include "libavutil/pixdesc.h"
 #include "libavutil/opt.h"
 #include "avfilter.h"
 #include "formats.h"
 #include "framesync.h"
 #include "internal.h"
 #include "video.h"
 
 typedef struct RemapContext {
     const AVClass *class;
     int nb_planes;
     int nb_components;
     int step;
     FFFrameSync fs;
 
     void (*remap)(struct RemapContext *s, const AVFrame *in,
                   const AVFrame *xin, const AVFrame *yin,
                   AVFrame *out);
 } RemapContext;
 
 #define OFFSET(x) offsetof(RemapContext, x)
 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 
 static const AVOption remap_options[] = {
     { NULL }
 };
 
 AVFILTER_DEFINE_CLASS(remap);
 
 static int query_formats(AVFilterContext *ctx)
 {
     static const enum AVPixelFormat pix_fmts[] = {
         AV_PIX_FMT_YUVA444P,
         AV_PIX_FMT_YUV444P,
         AV_PIX_FMT_YUVJ444P,
         AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
         AV_PIX_FMT_ARGB, AV_PIX_FMT_ABGR, AV_PIX_FMT_RGBA, AV_PIX_FMT_BGRA,
         AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP,

         AV_PIX_FMT_YUV444P9, AV_PIX_FMT_YUV444P10, AV_PIX_FMT_YUV444P12,
         AV_PIX_FMT_YUV444P14, AV_PIX_FMT_YUV444P16,
         AV_PIX_FMT_YUVA444P9, AV_PIX_FMT_YUVA444P10, AV_PIX_FMT_YUVA444P16,
         AV_PIX_FMT_GBRP9, AV_PIX_FMT_GBRP10, AV_PIX_FMT_GBRP12,
         AV_PIX_FMT_GBRP14, AV_PIX_FMT_GBRP16,
         AV_PIX_FMT_GBRAP10, AV_PIX_FMT_GBRAP12, AV_PIX_FMT_GBRAP16,
         AV_PIX_FMT_RGB48, AV_PIX_FMT_BGR48,
         AV_PIX_FMT_RGBA64, AV_PIX_FMT_BGRA64,

         AV_PIX_FMT_NONE
     };
     static const enum AVPixelFormat map_fmts[] = {
         AV_PIX_FMT_GRAY16,
         AV_PIX_FMT_NONE
     };
     AVFilterFormats *pix_formats = NULL, *map_formats = NULL;
     int ret;
 
     if (!(pix_formats = ff_make_format_list(pix_fmts)) ||
         !(map_formats = ff_make_format_list(map_fmts))) {
         ret = AVERROR(ENOMEM);
         goto fail;
     }
     if ((ret = ff_formats_ref(pix_formats, &ctx->inputs[0]->out_formats)) < 0 ||
         (ret = ff_formats_ref(map_formats, &ctx->inputs[1]->out_formats)) < 0 ||
         (ret = ff_formats_ref(map_formats, &ctx->inputs[2]->out_formats)) < 0 ||
         (ret = ff_formats_ref(pix_formats, &ctx->outputs[0]->in_formats)) < 0)
         goto fail;
     return 0;
 fail:
     if (pix_formats)
         av_freep(&pix_formats->formats);
     av_freep(&pix_formats);
     if (map_formats)
         av_freep(&map_formats->formats);
     av_freep(&map_formats);
     return ret;
 }
 
 /**
  * remap_planar algorithm expects planes of same size
  * pixels are copied from source to target using :
  * Target_frame[y][x] = Source_frame[ ymap[y][x] ][ [xmap[y][x] ];
  */
 static void remap_planar(RemapContext *s, const AVFrame *in,
                          const AVFrame *xin, const AVFrame *yin,
                          AVFrame *out)
 {
     const int xlinesize = xin->linesize[0] / 2;
     const int ylinesize = yin->linesize[0] / 2;
     int x , y, plane;
 
     for (plane = 0; plane < s->nb_planes ; plane++) {
         uint8_t *dst         = out->data[plane];
         const int dlinesize  = out->linesize[plane];
         const uint8_t *src   = in->data[plane];
         const int slinesize  = in->linesize[plane];
         const uint16_t *xmap = (const uint16_t *)xin->data[0];
         const uint16_t *ymap = (const uint16_t *)yin->data[0];
 
         for (y = 0; y < out->height; y++) {
             for (x = 0; x < out->width; x++) {
                 if (ymap[x] < in->height && xmap[x] < in->width) {
                     dst[x] = src[ymap[x] * slinesize + xmap[x]];
                 } else {
                     dst[x] = 0;
                 }
             }
             dst  += dlinesize;
             xmap += xlinesize;
             ymap += ylinesize;
         }
     }
 }
 

 static void remap_planar16(RemapContext *s, const AVFrame *in,
                            const AVFrame *xin, const AVFrame *yin,
                            AVFrame *out)
 {
     const int xlinesize = xin->linesize[0] / 2;
     const int ylinesize = yin->linesize[0] / 2;
     int x , y, plane;
 
     for (plane = 0; plane < s->nb_planes ; plane++) {
         uint16_t *dst        = (uint16_t *)out->data[plane];
         const int dlinesize  = out->linesize[plane] / 2;
         const uint16_t *src  = (const uint16_t *)in->data[plane];
         const int slinesize  = in->linesize[plane] / 2;
         const uint16_t *xmap = (const uint16_t *)xin->data[0];
         const uint16_t *ymap = (const uint16_t *)yin->data[0];
 
         for (y = 0; y < out->height; y++) {
             for (x = 0; x < out->width; x++) {
                 if (ymap[x] < in->height && xmap[x] < in->width) {
                     dst[x] = src[ymap[x] * slinesize + xmap[x]];
                 } else {
                     dst[x] = 0;
                 }
             }
             dst  += dlinesize;
             xmap += xlinesize;
             ymap += ylinesize;
         }
     }
 }
 

 /**
  * remap_packed algorithm expects pixels with both padded bits (step) and
  * number of components correctly set.
  * pixels are copied from source to target using :
  * Target_frame[y][x] = Source_frame[ ymap[y][x] ][ [xmap[y][x] ];
  */
 static void remap_packed(RemapContext *s, const AVFrame *in,
                          const AVFrame *xin, const AVFrame *yin,
                          AVFrame *out)
 {
     uint8_t *dst = out->data[0];
     const uint8_t *src  = in->data[0];
     const int dlinesize = out->linesize[0];
     const int slinesize = in->linesize[0];
     const int xlinesize = xin->linesize[0] / 2;
     const int ylinesize = yin->linesize[0] / 2;
     const uint16_t *xmap = (const uint16_t *)xin->data[0];
     const uint16_t *ymap = (const uint16_t *)yin->data[0];
     const int step = s->step;
     int c, x, y;
 
     for (y = 0; y < out->height; y++) {
         for (x = 0; x < out->width; x++) {
             for (c = 0; c < s->nb_components; c++) {
                 if (ymap[x] < in->height && xmap[x] < in->width) {
                     dst[x * step + c] = src[ymap[x] * slinesize + xmap[x] * step + c];
                 } else {
                     dst[x * step + c] = 0;
                 }
             }
         }
         dst  += dlinesize;
         xmap += xlinesize;
         ymap += ylinesize;
     }
 }
 

 static void remap_packed16(RemapContext *s, const AVFrame *in,
                            const AVFrame *xin, const AVFrame *yin,
                            AVFrame *out)
 {
     uint16_t *dst = (uint16_t *)out->data[0];
     const uint16_t *src  = (const uint16_t *)in->data[0];
     const int dlinesize = out->linesize[0] / 2;
     const int slinesize = in->linesize[0] / 2;
     const int xlinesize = xin->linesize[0] / 2;
     const int ylinesize = yin->linesize[0] / 2;
     const uint16_t *xmap = (const uint16_t *)xin->data[0];
     const uint16_t *ymap = (const uint16_t *)yin->data[0];
     const int step = s->step / 2;
     int c, x, y;
 
     for (y = 0; y < out->height; y++) {
         for (x = 0; x < out->width; x++) {
             for (c = 0; c < s->nb_components; c++) {
                 if (ymap[x] < in->height && xmap[x] < in->width) {
                     dst[x * step + c] = src[ymap[x] * slinesize + xmap[x] * step + c];
                 } else {
                     dst[x * step + c] = 0;
                 }
             }
         }
         dst  += dlinesize;
         xmap += xlinesize;
         ymap += ylinesize;
     }
 }
 

 static int config_input(AVFilterLink *inlink)
 {
     AVFilterContext *ctx = inlink->dst;
     RemapContext *s = ctx->priv;
     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
 
     s->nb_planes = av_pix_fmt_count_planes(inlink->format);
     s->nb_components = desc->nb_components;
 

     if (desc->comp[0].depth == 8) {
         if (s->nb_planes > 1 || s->nb_components == 1) {
             s->remap = remap_planar;
         } else {
             s->remap = remap_packed;
         }

     } else {

         if (s->nb_planes > 1 || s->nb_components == 1) {
             s->remap = remap_planar16;
         } else {
             s->remap = remap_packed16;
         }

     }
 
     s->step = av_get_padded_bits_per_pixel(desc) >> 3;
     return 0;
 }
 
 static int process_frame(FFFrameSync *fs)
 {
     AVFilterContext *ctx = fs->parent;
     RemapContext *s = fs->opaque;
     AVFilterLink *outlink = ctx->outputs[0];
     AVFrame *out, *in, *xpic, *ypic;
     int ret;
 
     if ((ret = ff_framesync_get_frame(&s->fs, 0, &in,   0)) < 0 ||
         (ret = ff_framesync_get_frame(&s->fs, 1, &xpic, 0)) < 0 ||
         (ret = ff_framesync_get_frame(&s->fs, 2, &ypic, 0)) < 0)
         return ret;
 
     if (ctx->is_disabled) {
         out = av_frame_clone(in);
         if (!out)
             return AVERROR(ENOMEM);
     } else {
         out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
         if (!out)
             return AVERROR(ENOMEM);
         av_frame_copy_props(out, in);
 
         s->remap(s, in, xpic, ypic, out);
     }
     out->pts = av_rescale_q(in->pts, s->fs.time_base, outlink->time_base);
 
     return ff_filter_frame(outlink, out);
 }
 
 static int config_output(AVFilterLink *outlink)
 {
     AVFilterContext *ctx = outlink->src;
     RemapContext *s = ctx->priv;
     AVFilterLink *srclink = ctx->inputs[0];
     AVFilterLink *xlink = ctx->inputs[1];
     AVFilterLink *ylink = ctx->inputs[2];
     FFFrameSyncIn *in;
     int ret;
 
     if (xlink->w != ylink->w || xlink->h != ylink->h) {
         av_log(ctx, AV_LOG_ERROR, "Second input link %s parameters "
                "(size %dx%d) do not match the corresponding "
                "third input link %s parameters (%dx%d)\n",
                ctx->input_pads[1].name, xlink->w, xlink->h,
                ctx->input_pads[2].name, ylink->w, ylink->h);
         return AVERROR(EINVAL);
     }
 
     outlink->w = xlink->w;
     outlink->h = xlink->h;
     outlink->time_base = srclink->time_base;
     outlink->sample_aspect_ratio = srclink->sample_aspect_ratio;
     outlink->frame_rate = srclink->frame_rate;
 
     ret = ff_framesync_init(&s->fs, ctx, 3);
     if (ret < 0)
         return ret;
 
     in = s->fs.in;
     in[0].time_base = srclink->time_base;
     in[1].time_base = xlink->time_base;
     in[2].time_base = ylink->time_base;
     in[0].sync   = 2;
     in[0].before = EXT_STOP;
     in[0].after  = EXT_STOP;
     in[1].sync   = 1;
     in[1].before = EXT_NULL;
     in[1].after  = EXT_INFINITY;
     in[2].sync   = 1;
     in[2].before = EXT_NULL;
     in[2].after  = EXT_INFINITY;
     s->fs.opaque   = s;
     s->fs.on_event = process_frame;
 
     return ff_framesync_configure(&s->fs);
 }
 
 static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
 {
     RemapContext *s = inlink->dst->priv;
     return ff_framesync_filter_frame(&s->fs, inlink, buf);
 }
 
 static int request_frame(AVFilterLink *outlink)
 {
     RemapContext *s = outlink->src->priv;
     return ff_framesync_request_frame(&s->fs, outlink);
 }
 
 static av_cold void uninit(AVFilterContext *ctx)
 {
     RemapContext *s = ctx->priv;
 
     ff_framesync_uninit(&s->fs);
 }
 
 static const AVFilterPad remap_inputs[] = {
     {
         .name         = "source",
         .type         = AVMEDIA_TYPE_VIDEO,
         .filter_frame = filter_frame,
         .config_props = config_input,
     },
     {
         .name         = "xmap",
         .type         = AVMEDIA_TYPE_VIDEO,
         .filter_frame = filter_frame,
     },
     {
         .name         = "ymap",
         .type         = AVMEDIA_TYPE_VIDEO,
         .filter_frame = filter_frame,
     },
     { NULL }
 };
 
 static const AVFilterPad remap_outputs[] = {
     {
         .name          = "default",
         .type          = AVMEDIA_TYPE_VIDEO,
         .config_props  = config_output,
         .request_frame = request_frame,
     },
     { NULL }
 };
 
 AVFilter ff_vf_remap = {
     .name          = "remap",
     .description   = NULL_IF_CONFIG_SMALL("Remap pixels"),
     .priv_size     = sizeof(RemapContext),
     .uninit        = uninit,
     .query_formats = query_formats,
     .inputs        = remap_inputs,
     .outputs       = remap_outputs,
     .priv_class    = &remap_class,
     .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
 };