/*
  * Copyright (c) 2019 Paul B Mahol
  *
  * 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 "libavutil/imgutils.h"
 #include "libavutil/pixdesc.h"
 #include "libavutil/opt.h"
 #include "avfilter.h"
 #include "formats.h"
 #include "internal.h"
 #include "video.h"
 #include "framesync.h"
 
 #define OFFSET(x) offsetof(MaskedMinMaxContext, x)
 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 
 typedef struct ThreadData {
     AVFrame *src, *f1, *f2, *dst;
 } ThreadData;
 
 typedef struct MaskedMinMaxContext {
     const AVClass *class;
 
     int planes;
     int maskedmin;
 
     int linesize[4];
     int planewidth[4], planeheight[4];
     int nb_planes;
     int depth;
     FFFrameSync fs;
 
     void (*maskedminmax)(const uint8_t *src, uint8_t *dst, const uint8_t *f1, const uint8_t *f2, int w);
 } MaskedMinMaxContext;
 
 static const AVOption maskedminmax_options[] = {
     { "planes",     "set planes",     OFFSET(planes),     AV_OPT_TYPE_INT, {.i64=0xF}, 0, 0xF,        FLAGS },
     { NULL }
 };
 
 static av_cold int init(AVFilterContext *ctx)
 {
     MaskedMinMaxContext *s = ctx->priv;
 
     s->maskedmin = !strcmp(ctx->filter->name, "maskedmin");
 
     return 0;
 }
 
 static int query_formats(AVFilterContext *ctx)
 {
     static const enum AVPixelFormat pix_fmts[] = {
         AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV440P,
         AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P,
         AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUV420P,
         AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P,
         AV_PIX_FMT_YUVJ411P, AV_PIX_FMT_YUV411P, AV_PIX_FMT_YUV410P,
         AV_PIX_FMT_YUV420P9, AV_PIX_FMT_YUV422P9, AV_PIX_FMT_YUV444P9,
         AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV444P10,
         AV_PIX_FMT_YUV420P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV444P12, AV_PIX_FMT_YUV440P12,
         AV_PIX_FMT_YUV420P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV444P14,
         AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
         AV_PIX_FMT_YUVA420P9, AV_PIX_FMT_YUVA422P9, AV_PIX_FMT_YUVA444P9,
         AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA444P10,

         AV_PIX_FMT_YUVA422P12, AV_PIX_FMT_YUVA444P12,

         AV_PIX_FMT_YUVA420P16, AV_PIX_FMT_YUVA422P16, AV_PIX_FMT_YUVA444P16,
         AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRP9, AV_PIX_FMT_GBRP10,
         AV_PIX_FMT_GBRP12, AV_PIX_FMT_GBRP14, AV_PIX_FMT_GBRP16,
         AV_PIX_FMT_GBRAP, AV_PIX_FMT_GBRAP10, AV_PIX_FMT_GBRAP12, AV_PIX_FMT_GBRAP16,
         AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY9, AV_PIX_FMT_GRAY10, AV_PIX_FMT_GRAY12, AV_PIX_FMT_GRAY14, AV_PIX_FMT_GRAY16,
         AV_PIX_FMT_NONE
     };
 
     return ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
 }
 
 static void maskedmin8(const uint8_t *src, uint8_t *dst, const uint8_t *f1, const uint8_t *f2, int w)
 {
     for (int x = 0; x < w; x++)
         dst[x] = FFABS(src[x] - f2[x]) < FFABS(src[x] - f1[x]) ? f2[x] : f1[x];
 }
 
 static void maskedmax8(const uint8_t *src, uint8_t *dst, const uint8_t *f1, const uint8_t *f2, int w)
 {
     for (int x = 0; x < w; x++)
         dst[x] = FFABS(src[x] - f2[x]) > FFABS(src[x] - f1[x]) ? f2[x] : f1[x];
 }
 
 static void maskedmin16(const uint8_t *ssrc, uint8_t *ddst, const uint8_t *ff1, const uint8_t *ff2, int w)
 {
     const uint16_t *src = (const uint16_t *)ssrc;
     const uint16_t *f1 = (const uint16_t *)ff1;
     const uint16_t *f2 = (const uint16_t *)ff2;
     uint16_t *dst = (uint16_t *)ddst;
 
     for (int x = 0; x < w; x++)
         dst[x] = FFABS(src[x] - f2[x]) < FFABS(src[x] - f1[x]) ? f2[x] : f1[x];
 }
 
 static void maskedmax16(const uint8_t *ssrc, uint8_t *ddst, const uint8_t *ff1, const uint8_t *ff2, int w)
 {
     const uint16_t *src = (const uint16_t *)ssrc;
     const uint16_t *f1 = (const uint16_t *)ff1;
     const uint16_t *f2 = (const uint16_t *)ff2;
     uint16_t *dst = (uint16_t *)ddst;
 
     for (int x = 0; x < w; x++)
         dst[x] = FFABS(src[x] - f2[x]) > FFABS(src[x] - f1[x]) ? f2[x] : f1[x];
 }
 
 static int config_input(AVFilterLink *inlink)
 {
     AVFilterContext *ctx = inlink->dst;
     MaskedMinMaxContext *s = ctx->priv;
     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
     int vsub, hsub, ret;
 
     s->nb_planes = av_pix_fmt_count_planes(inlink->format);
 
     if ((ret = av_image_fill_linesizes(s->linesize, inlink->format, inlink->w)) < 0)
         return ret;
 
     hsub = desc->log2_chroma_w;
     vsub = desc->log2_chroma_h;
     s->planeheight[1] = s->planeheight[2] = AV_CEIL_RSHIFT(inlink->h, vsub);
     s->planeheight[0] = s->planeheight[3] = inlink->h;
     s->planewidth[1]  = s->planewidth[2]  = AV_CEIL_RSHIFT(inlink->w, hsub);
     s->planewidth[0]  = s->planewidth[3]  = inlink->w;
 
     s->depth = desc->comp[0].depth;
 
     if (desc->comp[0].depth == 8)
         s->maskedminmax = s->maskedmin ? maskedmin8  : maskedmax8;
     else
         s->maskedminmax = s->maskedmin ? maskedmin16 : maskedmax16;
 
     return 0;
 }
 
 static int maskedminmax_slice(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs)
 {
     MaskedMinMaxContext *s = ctx->priv;
     ThreadData *td = arg;
 
     for (int p = 0; p < s->nb_planes; p++) {
         const ptrdiff_t src_linesize = td->src->linesize[p];
         const ptrdiff_t f1_linesize = td->f1->linesize[p];
         const ptrdiff_t f2_linesize = td->f2->linesize[p];
         const ptrdiff_t dst_linesize = td->dst->linesize[p];
         const int w = s->planewidth[p];
         const int h = s->planeheight[p];
         const int slice_start = (h * jobnr) / nb_jobs;
         const int slice_end = (h * (jobnr+1)) / nb_jobs;
         const uint8_t *src = td->src->data[p] + slice_start * src_linesize;
         const uint8_t *f1 = td->f1->data[p] + slice_start * f1_linesize;
         const uint8_t *f2 = td->f2->data[p] + slice_start * f2_linesize;
         uint8_t *dst = td->dst->data[p] + slice_start * dst_linesize;
 
         if (!((1 << p) & s->planes)) {
             av_image_copy_plane(dst, dst_linesize, src, src_linesize,
                                 s->linesize[p], slice_end - slice_start);
             continue;
         }
 
         for (int y = slice_start; y < slice_end; y++) {
             s->maskedminmax(src, dst, f1, f2, w);
 
             dst += dst_linesize;
             src += src_linesize;
             f1  += f1_linesize;
             f2  += f2_linesize;
         }
     }
 
     return 0;
 }
 
 static int process_frame(FFFrameSync *fs)
 {
     AVFilterContext *ctx = fs->parent;
     MaskedMinMaxContext *s = fs->opaque;
     AVFilterLink *outlink = ctx->outputs[0];
     AVFrame *out, *src, *f1, *f2;
     int ret;
 
     if ((ret = ff_framesync_get_frame(&s->fs, 0, &src, 0)) < 0 ||
         (ret = ff_framesync_get_frame(&s->fs, 1, &f1,  0)) < 0 ||
         (ret = ff_framesync_get_frame(&s->fs, 2, &f2,  0)) < 0)
         return ret;
 
     if (ctx->is_disabled) {
         out = av_frame_clone(src);
         if (!out)
             return AVERROR(ENOMEM);
     } else {
         ThreadData td;
 
         out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
         if (!out)
             return AVERROR(ENOMEM);
         av_frame_copy_props(out, src);
 
         td.src = src;
         td.f1 = f1;
         td.f2 = f2;
         td.dst = out;
 
         ctx->internal->execute(ctx, maskedminmax_slice, &td, NULL, FFMIN(s->planeheight[0],
                                                                    ff_filter_get_nb_threads(ctx)));
     }
     out->pts = av_rescale_q(s->fs.pts, s->fs.time_base, outlink->time_base);
 
     return ff_filter_frame(outlink, out);
 }
 
 static int config_output(AVFilterLink *outlink)
 {
     AVFilterContext *ctx = outlink->src;
     MaskedMinMaxContext *s = ctx->priv;
     AVFilterLink *source = ctx->inputs[0];
     AVFilterLink *f1 = ctx->inputs[1];
     AVFilterLink *f2 = ctx->inputs[2];
     FFFrameSyncIn *in;
     int ret;
 
     if (source->format != f1->format ||
         source->format != f2->format) {
         av_log(ctx, AV_LOG_ERROR, "inputs must be of same pixel format\n");
         return AVERROR(EINVAL);
     }
     if (source->w != f1->w || source->h != f1->h ||
         source->w != f2->w || source->h != f2->h) {
         av_log(ctx, AV_LOG_ERROR, "First input link %s parameters "
                "(size %dx%d) do not match the corresponding "
                "second input link %s parameters (%dx%d) "
                "and/or third input link %s parameters (size %dx%d)\n",
                ctx->input_pads[0].name, source->w, source->h,
                ctx->input_pads[1].name, f1->w, f1->h,
                ctx->input_pads[2].name, f2->w, f2->h);
         return AVERROR(EINVAL);
     }
 
     outlink->w = source->w;
     outlink->h = source->h;
     outlink->sample_aspect_ratio = source->sample_aspect_ratio;
     outlink->frame_rate = source->frame_rate;
 
     if ((ret = ff_framesync_init(&s->fs, ctx, 3)) < 0)
         return ret;
 
     in = s->fs.in;
     in[0].time_base = source->time_base;
     in[1].time_base = f1->time_base;
     in[2].time_base = f2->time_base;
     in[0].sync   = 1;
     in[0].before = EXT_STOP;
     in[0].after  = EXT_INFINITY;
     in[1].sync   = 1;
     in[1].before = EXT_STOP;
     in[1].after  = EXT_INFINITY;
     in[2].sync   = 1;
     in[2].before = EXT_STOP;
     in[2].after  = EXT_INFINITY;
     s->fs.opaque   = s;
     s->fs.on_event = process_frame;
 
     ret = ff_framesync_configure(&s->fs);
     outlink->time_base = s->fs.time_base;
 
     return ret;
 }
 
 static int activate(AVFilterContext *ctx)
 {
     MaskedMinMaxContext *s = ctx->priv;
     return ff_framesync_activate(&s->fs);
 }
 
 static av_cold void uninit(AVFilterContext *ctx)
 {
     MaskedMinMaxContext *s = ctx->priv;
 
     ff_framesync_uninit(&s->fs);
 }
 
 static const AVFilterPad maskedminmax_inputs[] = {
     {
         .name         = "source",
         .type         = AVMEDIA_TYPE_VIDEO,
         .config_props = config_input,
     },
     {
         .name         = "filter1",
         .type         = AVMEDIA_TYPE_VIDEO,
     },
     {
         .name         = "filter2",
         .type         = AVMEDIA_TYPE_VIDEO,
     },
     { NULL }
 };
 
 static const AVFilterPad maskedminmax_outputs[] = {
     {
         .name          = "default",
         .type          = AVMEDIA_TYPE_VIDEO,
         .config_props  = config_output,
     },
     { NULL }
 };
 
 #define maskedmin_options maskedminmax_options
 AVFILTER_DEFINE_CLASS(maskedmin);
 
 AVFilter ff_vf_maskedmin = {
     .name          = "maskedmin",
     .description   = NULL_IF_CONFIG_SMALL("Apply filtering with minimum difference of two streams."),
     .priv_class    = &maskedmin_class,
     .priv_size     = sizeof(MaskedMinMaxContext),
     .init          = init,
     .uninit        = uninit,
     .activate      = activate,
     .query_formats = query_formats,
     .inputs        = maskedminmax_inputs,
     .outputs       = maskedminmax_outputs,
     .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL | AVFILTER_FLAG_SLICE_THREADS,
 };
 
 #define maskedmax_options maskedminmax_options
 AVFILTER_DEFINE_CLASS(maskedmax);
 
 AVFilter ff_vf_maskedmax = {
     .name          = "maskedmax",
     .description   = NULL_IF_CONFIG_SMALL("Apply filtering with maximum difference of two streams."),
     .priv_class    = &maskedmax_class,
     .priv_size     = sizeof(MaskedMinMaxContext),
     .init          = init,
     .uninit        = uninit,
     .activate      = activate,
     .query_formats = query_formats,
     .inputs        = maskedminmax_inputs,
     .outputs       = maskedminmax_outputs,
     .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL | AVFILTER_FLAG_SLICE_THREADS,
 };