/*

  * 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
  * Bauer stereo-to-binaural filter
  */
 
 #include <bs2b.h>
 
 #include "libavutil/channel_layout.h"
 #include "libavutil/common.h"
 #include "libavutil/opt.h"
 
 #include "audio.h"
 #include "avfilter.h"
 #include "formats.h"
 #include "internal.h"
 

 typedef void (*filter_func)(t_bs2bdp bs2bdp, uint8_t *sample, int n);
 

 typedef struct Bs2bContext {
     const AVClass *class;
 
     int profile;
     int fcut;
     int feed;
 
     t_bs2bdp bs2bp;
 

     filter_func filter;

 } Bs2bContext;
 
 #define OFFSET(x) offsetof(Bs2bContext, x)

 #define A AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_FILTERING_PARAM

 static const AVOption bs2b_options[] = {

     { "profile", "Apply a pre-defined crossfeed level",
             OFFSET(profile), AV_OPT_TYPE_INT, { .i64 = BS2B_DEFAULT_CLEVEL }, 0, INT_MAX, A, "profile" },
         { "default", "default profile", 0, AV_OPT_TYPE_CONST, { .i64 = BS2B_DEFAULT_CLEVEL }, 0, 0, A, "profile" },
         { "cmoy",    "Chu Moy circuit", 0, AV_OPT_TYPE_CONST, { .i64 = BS2B_CMOY_CLEVEL    }, 0, 0, A, "profile" },
         { "jmeier",  "Jan Meier circuit", 0, AV_OPT_TYPE_CONST, { .i64 = BS2B_JMEIER_CLEVEL  }, 0, 0, A, "profile" },
     { "fcut", "Set cut frequency (in Hz)",
             OFFSET(fcut), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, BS2B_MAXFCUT, A },
     { "feed", "Set feed level (in Hz)",
             OFFSET(feed), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, BS2B_MAXFEED, A },
     { NULL },
 };
 

 AVFILTER_DEFINE_CLASS(bs2b);

 
 static av_cold int init(AVFilterContext *ctx)
 {
     Bs2bContext *bs2b = ctx->priv;
 
     if (!(bs2b->bs2bp = bs2b_open()))
         return AVERROR(ENOMEM);
 
     bs2b_set_level(bs2b->bs2bp, bs2b->profile);
 
     if (bs2b->fcut)
         bs2b_set_level_fcut(bs2b->bs2bp, bs2b->fcut);
 
     if (bs2b->feed)
         bs2b_set_level_feed(bs2b->bs2bp, bs2b->feed);
 
     return 0;
 }
 
 static av_cold void uninit(AVFilterContext *ctx)
 {
     Bs2bContext *bs2b = ctx->priv;
 
     if (bs2b->bs2bp)
         bs2b_close(bs2b->bs2bp);
 }
 
 static int query_formats(AVFilterContext *ctx)
 {
     AVFilterFormats *formats = NULL;
     AVFilterChannelLayouts *layouts = NULL;
 
     static const enum AVSampleFormat sample_fmts[] = {
         AV_SAMPLE_FMT_U8,
         AV_SAMPLE_FMT_S16,
         AV_SAMPLE_FMT_S32,
         AV_SAMPLE_FMT_FLT,
         AV_SAMPLE_FMT_DBL,
         AV_SAMPLE_FMT_NONE,
     };

     int ret;

 
     if (ff_add_channel_layout(&layouts, AV_CH_LAYOUT_STEREO) != 0)
         return AVERROR(ENOMEM);

     ret = ff_set_common_channel_layouts(ctx, layouts);
     if (ret < 0)
         return ret;

 
     formats = ff_make_format_list(sample_fmts);
     if (!formats)
         return AVERROR(ENOMEM);

     ret = ff_set_common_formats(ctx, formats);
     if (ret < 0)
         return ret;

 
     formats = ff_all_samplerates();
     if (!formats)
         return AVERROR(ENOMEM);

     return ff_set_common_samplerates(ctx, formats);

 }
 
 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
 {
     int ret;
     AVFrame *out_frame;
 
     Bs2bContext     *bs2b = inlink->dst->priv;
     AVFilterLink *outlink = inlink->dst->outputs[0];
 
     if (av_frame_is_writable(frame)) {
         out_frame = frame;
     } else {
         out_frame = ff_get_audio_buffer(inlink, frame->nb_samples);

         if (!out_frame) {
             av_frame_free(&frame);

             return AVERROR(ENOMEM);

         }

         av_frame_copy(out_frame, frame);
         ret = av_frame_copy_props(out_frame, frame);
         if (ret < 0) {
             av_frame_free(&out_frame);
             av_frame_free(&frame);
             return ret;
         }
     }
 
     bs2b->filter(bs2b->bs2bp, out_frame->extended_data[0], out_frame->nb_samples);
 
     if (frame != out_frame)
         av_frame_free(&frame);
 
     return ff_filter_frame(outlink, out_frame);
 }
 
 static int config_output(AVFilterLink *outlink)
 {
     AVFilterContext *ctx = outlink->src;
     Bs2bContext    *bs2b = ctx->priv;
     AVFilterLink *inlink = ctx->inputs[0];
 
     int srate = inlink->sample_rate;
 
     switch (inlink->format) {
     case AV_SAMPLE_FMT_U8:

         bs2b->filter = (filter_func) bs2b_cross_feed_u8;

         break;
     case AV_SAMPLE_FMT_S16:

         bs2b->filter = (filter_func) bs2b_cross_feed_s16;

         break;
     case AV_SAMPLE_FMT_S32:

         bs2b->filter = (filter_func) bs2b_cross_feed_s32;

         break;
     case AV_SAMPLE_FMT_FLT:

         bs2b->filter = (filter_func) bs2b_cross_feed_f;

         break;
     case AV_SAMPLE_FMT_DBL:

         bs2b->filter = (filter_func) bs2b_cross_feed_d;

         break;
     default:
         return AVERROR_BUG;
     }
 
     if ((srate < BS2B_MINSRATE) || (srate > BS2B_MAXSRATE))
         return AVERROR(ENOSYS);
 
     bs2b_set_srate(bs2b->bs2bp, srate);
 
     return 0;
 }
 
 static const AVFilterPad bs2b_inputs[] = {
     {
         .name           = "default",
         .type           = AVMEDIA_TYPE_AUDIO,
         .filter_frame   = filter_frame,
     },
     { NULL }
 };
 
 static const AVFilterPad bs2b_outputs[] = {
     {
         .name           = "default",
         .type           = AVMEDIA_TYPE_AUDIO,
         .config_props   = config_output,
     },
     { NULL }
 };
 
 AVFilter ff_af_bs2b = {
     .name           = "bs2b",
     .description    = NULL_IF_CONFIG_SMALL("Bauer stereo-to-binaural filter."),
     .query_formats  = query_formats,
     .priv_size      = sizeof(Bs2bContext),
     .priv_class     = &bs2b_class,
     .init           = init,
     .uninit         = uninit,
     .inputs         = bs2b_inputs,
     .outputs        = bs2b_outputs,
 };