/*
  * 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/opt.h"
 #include "libavutil/time.h"
 #include "avfilter.h"
 #include "formats.h"
 #include "internal.h"
 
 enum BenchAction {
     ACTION_START,
     ACTION_STOP,
     NB_ACTION
 };
 

 typedef struct BenchContext {

     const AVClass *class;
     int action;
     int64_t max, min;
     int64_t sum;
     int n;
 } BenchContext;
 
 #define OFFSET(x) offsetof(BenchContext, x)
 #define DEFINE_OPTIONS(filt_name, FLAGS)                                                                                \
 static const AVOption filt_name##_options[] = {                                                                         \
     { "action", "set action", OFFSET(action), AV_OPT_TYPE_INT, {.i64=ACTION_START}, 0, NB_ACTION-1, FLAGS, "action" },  \
         { "start", "start timer",  0, AV_OPT_TYPE_CONST, {.i64=ACTION_START}, INT_MIN, INT_MAX, FLAGS, "action" },      \
         { "stop",  "stop timer",   0, AV_OPT_TYPE_CONST, {.i64=ACTION_STOP},  INT_MIN, INT_MAX, FLAGS, "action" },      \
     { NULL }                                                                                                            \
 }
 
 #define START_TIME_KEY "lavfi.bench.start_time"
 #define T2F(v) ((v) / 1000000.)
 
 static av_cold int init(AVFilterContext *ctx)
 {
     BenchContext *s = ctx->priv;
     s->min = INT64_MAX;
     s->max = INT64_MIN;
     return 0;
 }
 
 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
 {
     AVFilterContext *ctx = inlink->dst;
     BenchContext *s = ctx->priv;
     AVFilterLink *outlink = ctx->outputs[0];
     const int64_t t = av_gettime();
 
     if (t < 0)
         return ff_filter_frame(outlink, in);
 
     if (s->action == ACTION_START) {
         av_dict_set_int(&in->metadata, START_TIME_KEY, t, 0);

     } else if (s->action == ACTION_STOP) {

         AVDictionaryEntry *e = av_dict_get(in->metadata, START_TIME_KEY, NULL, 0);
         if (e) {
             const int64_t start = strtoll(e->value, NULL, 0);
             const int64_t diff = t - start;
             s->sum += diff;
             s->n++;
             s->min = FFMIN(s->min, diff);
             s->max = FFMAX(s->max, diff);
             av_log(s, AV_LOG_INFO, "t:%f avg:%f max:%f min:%f\n",
                    T2F(diff), T2F(s->sum / s->n), T2F(s->max), T2F(s->min));
         }
         av_dict_set(&in->metadata, START_TIME_KEY, NULL, 0);
     }
 
     return ff_filter_frame(outlink, in);
 }
 
 #if CONFIG_BENCH_FILTER
 DEFINE_OPTIONS(bench, AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM);
 AVFILTER_DEFINE_CLASS(bench);
 
 static const AVFilterPad bench_inputs[] = {
     {
         .name         = "default",
         .type         = AVMEDIA_TYPE_VIDEO,
         .filter_frame = filter_frame,
     },
     { NULL }
 };
 
 static const AVFilterPad bench_outputs[] = {
     {
         .name = "default",
         .type = AVMEDIA_TYPE_VIDEO,
     },
     { NULL }
 };
 
 AVFilter ff_vf_bench = {
     .name          = "bench",
     .description   = NULL_IF_CONFIG_SMALL("Benchmark part of a filtergraph."),
     .priv_size     = sizeof(BenchContext),
     .init          = init,
     .inputs        = bench_inputs,
     .outputs       = bench_outputs,
     .priv_class    = &bench_class,
 };
 #endif /* CONFIG_BENCH_FILTER */
 
 #if CONFIG_ABENCH_FILTER
 DEFINE_OPTIONS(abench, AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_AUDIO_PARAM);
 AVFILTER_DEFINE_CLASS(abench);
 
 static const AVFilterPad abench_inputs[] = {
     {
         .name         = "default",
         .type         = AVMEDIA_TYPE_AUDIO,
         .filter_frame = filter_frame,
     },
     { NULL }
 };
 
 static const AVFilterPad abench_outputs[] = {
     {
         .name = "default",
         .type = AVMEDIA_TYPE_AUDIO,
     },
     { NULL }
 };
 
 AVFilter ff_af_abench = {
     .name          = "abench",
     .description   = NULL_IF_CONFIG_SMALL("Benchmark part of a filtergraph."),
     .priv_size     = sizeof(BenchContext),
     .init          = init,
     .inputs        = abench_inputs,
     .outputs       = abench_outputs,
     .priv_class    = &abench_class,
 };
 #endif /* CONFIG_ABENCH_FILTER */