/*
  * Copyright (c) 2015 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
  */
 
 /**
  * @file
  * audio to video multimedia aphasemeter filter
  */
 
 #include "libavutil/avassert.h"
 #include "libavutil/channel_layout.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/opt.h"
 #include "libavutil/parseutils.h"
 #include "avfilter.h"
 #include "formats.h"
 #include "audio.h"
 #include "video.h"
 #include "internal.h"
 
 typedef struct AudioPhaseMeterContext {
     const AVClass *class;
     AVFrame *out;

     int do_video;

     int w, h;
     AVRational frame_rate;
     int contrast[4];
     uint8_t *mpc_str;
     uint8_t mpc[4];
     int draw_median_phase;
 } AudioPhaseMeterContext;
 
 #define OFFSET(x) offsetof(AudioPhaseMeterContext, x)
 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 
 static const AVOption aphasemeter_options[] = {

     { "rate", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, INT_MAX, FLAGS },
     { "r",    "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, INT_MAX, FLAGS },

     { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="800x400"}, 0, 0, FLAGS },
     { "s",    "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="800x400"}, 0, 0, FLAGS },
     { "rc", "set red contrast",   OFFSET(contrast[0]), AV_OPT_TYPE_INT, {.i64=2}, 0, 255, FLAGS },
     { "gc", "set green contrast", OFFSET(contrast[1]), AV_OPT_TYPE_INT, {.i64=7}, 0, 255, FLAGS },
     { "bc", "set blue contrast",  OFFSET(contrast[2]), AV_OPT_TYPE_INT, {.i64=1}, 0, 255, FLAGS },
     { "mpc", "set median phase color", OFFSET(mpc_str), AV_OPT_TYPE_STRING, {.str = "none"}, 0, 0, FLAGS },

     { "video", "set video output", OFFSET(do_video), AV_OPT_TYPE_BOOL, {.i64 = 1}, 0, 1, FLAGS },

     { NULL }
 };
 
 AVFILTER_DEFINE_CLASS(aphasemeter);
 
 static int query_formats(AVFilterContext *ctx)
 {

     AudioPhaseMeterContext *s = ctx->priv;

     AVFilterFormats *formats = NULL;
     AVFilterChannelLayouts *layout = NULL;
     AVFilterLink *inlink = ctx->inputs[0];
     AVFilterLink *outlink = ctx->outputs[0];
     static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_NONE };
     static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_RGBA, AV_PIX_FMT_NONE };

     int ret;

 
     formats = ff_make_format_list(sample_fmts);

     if ((ret = ff_formats_ref         (formats, &inlink->out_formats        )) < 0 ||

         (ret = ff_formats_ref         (formats, &outlink->in_formats        )) < 0 ||

         (ret = ff_add_channel_layout  (&layout, AV_CH_LAYOUT_STEREO         )) < 0 ||

         (ret = ff_channel_layouts_ref (layout , &inlink->out_channel_layouts)) < 0 ||
         (ret = ff_channel_layouts_ref (layout , &outlink->in_channel_layouts)) < 0)

         return ret;

 
     formats = ff_all_samplerates();

     if ((ret = ff_formats_ref(formats, &inlink->out_samplerates)) < 0 ||
         (ret = ff_formats_ref(formats, &outlink->in_samplerates)) < 0)

         return ret;

     if (s->do_video) {
         AVFilterLink *outlink = ctx->outputs[1];
 
         formats = ff_make_format_list(pix_fmts);
         if ((ret = ff_formats_ref(formats, &outlink->in_formats)) < 0)
             return ret;
     }

 
     return 0;
 }
 
 static int config_input(AVFilterLink *inlink)
 {
     AVFilterContext *ctx = inlink->dst;
     AudioPhaseMeterContext *s = ctx->priv;
     int nb_samples;
 

     if (s->do_video) {
         nb_samples = FFMAX(1024, ((double)inlink->sample_rate / av_q2d(s->frame_rate)) + 0.5);
         inlink->partial_buf_size =
         inlink->min_samples =
         inlink->max_samples = nb_samples;
     }

 
     return 0;
 }
 

 static int config_video_output(AVFilterLink *outlink)

 {
     AVFilterContext *ctx = outlink->src;
     AudioPhaseMeterContext *s = ctx->priv;
 
     outlink->w = s->w;
     outlink->h = s->h;
     outlink->sample_aspect_ratio = (AVRational){1,1};
     outlink->frame_rate = s->frame_rate;
 
     if (!strcmp(s->mpc_str, "none"))
         s->draw_median_phase = 0;
     else if (av_parse_color(s->mpc, s->mpc_str, -1, ctx) >= 0)
         s->draw_median_phase = 1;
     else
         return AVERROR(EINVAL);
 
     return 0;
 }
 
 static inline int get_x(float phase, int w)
 {
   return (phase + 1.) / 2. * (w - 1);
 }
 
 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
 {
     AVFilterContext *ctx = inlink->dst;
     AudioPhaseMeterContext *s = ctx->priv;

     AVFilterLink *outlink = s->do_video ? ctx->outputs[1] : NULL;
     AVFilterLink *aoutlink = ctx->outputs[0];

     AVDictionary **metadata;
     const int rc = s->contrast[0];
     const int gc = s->contrast[1];
     const int bc = s->contrast[2];
     float fphase = 0;
     AVFrame *out;
     uint8_t *dst;
     int i;
 

     if (s->do_video && (!s->out || s->out->width  != outlink->w ||
                                    s->out->height != outlink->h)) {

         av_frame_free(&s->out);
         s->out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
         if (!s->out) {
             av_frame_free(&in);
             return AVERROR(ENOMEM);
         }
 
         out = s->out;
         for (i = 0; i < outlink->h; i++)
             memset(out->data[0] + i * out->linesize[0], 0, outlink->w * 4);

     } else if (s->do_video) {

         out = s->out;
         for (i = outlink->h - 1; i >= 10; i--)
             memmove(out->data[0] + (i  ) * out->linesize[0],
                     out->data[0] + (i-1) * out->linesize[0],
                     outlink->w * 4);
         for (i = 0; i < outlink->w; i++)
             AV_WL32(out->data[0] + i * 4, 0);
     }
 
     for (i = 0; i < in->nb_samples; i++) {
         const float *src = (float *)in->data[0] + i * 2;
         const float f = src[0] * src[1] / (src[0]*src[0] + src[1] * src[1]) * 2;
         const float phase = isnan(f) ? 1 : f;
         const int x = get_x(phase, s->w);
 

         if (s->do_video) {
             dst = out->data[0] + x * 4;
             dst[0] = FFMIN(255, dst[0] + rc);
             dst[1] = FFMIN(255, dst[1] + gc);
             dst[2] = FFMIN(255, dst[2] + bc);
             dst[3] = 255;
         }

         fphase += phase;
     }
     fphase /= in->nb_samples;
 

     if (s->do_video) {
         if (s->draw_median_phase) {
             dst = out->data[0] + get_x(fphase, s->w) * 4;
             AV_WL32(dst, AV_RL32(s->mpc));
         }

         for (i = 1; i < 10 && i < outlink->h; i++)
             memcpy(out->data[0] + i * out->linesize[0], out->data[0], outlink->w * 4);
     }

     metadata = &in->metadata;

     if (metadata) {
         uint8_t value[128];
 
         snprintf(value, sizeof(value), "%f", fphase);
         av_dict_set(metadata, "lavfi.aphasemeter.phase", value, 0);
     }
 

     if (s->do_video) {
         s->out->pts = in->pts;
         ff_filter_frame(outlink, av_frame_clone(s->out));
     }
     return ff_filter_frame(aoutlink, in);

 }
 
 static av_cold void uninit(AVFilterContext *ctx)
 {
     AudioPhaseMeterContext *s = ctx->priv;

     int i;

 
     av_frame_free(&s->out);

     for (i = 0; i < ctx->nb_outputs; i++)
         av_freep(&ctx->output_pads[i].name);

 }
 

 static av_cold int init(AVFilterContext *ctx)
 {
     AudioPhaseMeterContext *s = ctx->priv;
     AVFilterPad pad;
 
     pad = (AVFilterPad){
         .name         = av_strdup("out0"),
         .type         = AVMEDIA_TYPE_AUDIO,
     };
     if (!pad.name)
         return AVERROR(ENOMEM);
     ff_insert_outpad(ctx, 0, &pad);
 
     if (s->do_video) {
         pad = (AVFilterPad){
             .name         = av_strdup("out1"),
             .type         = AVMEDIA_TYPE_VIDEO,
             .config_props = config_video_output,
         };
         if (!pad.name)
             return AVERROR(ENOMEM);
         ff_insert_outpad(ctx, 1, &pad);
     }
 
     return 0;
 }
 

 static const AVFilterPad inputs[] = {
     {
         .name         = "default",
         .type         = AVMEDIA_TYPE_AUDIO,
         .config_props = config_input,
         .filter_frame = filter_frame,
     },
     { NULL }
 };
 
 AVFilter ff_avf_aphasemeter = {
     .name          = "aphasemeter",
     .description   = NULL_IF_CONFIG_SMALL("Convert input audio to phase meter video output."),

     .init          = init,

     .uninit        = uninit,
     .query_formats = query_formats,
     .priv_size     = sizeof(AudioPhaseMeterContext),
     .inputs        = inputs,

     .outputs       = NULL,

     .priv_class    = &aphasemeter_class,

     .flags         = AVFILTER_FLAG_DYNAMIC_OUTPUTS,

 };