/*
  * Copyright (c) 2013 Georg Martius <georg dot martius at web dot de>
  *
  * 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
  */
 
 #define DEFAULT_RESULT_NAME     "transforms.trf"
 
 #include <vid.stab/libvidstab.h>
 
 #include "libavutil/common.h"
 #include "libavutil/opt.h"
 #include "libavutil/imgutils.h"
 #include "avfilter.h"
 #include "internal.h"
 
 #include "vidstabutils.h"
 

 typedef struct StabData {

     const AVClass *class;

 
     VSMotionDetect md;
     VSMotionDetectConfig conf;
 

     char *result;
     FILE *f;

 } StabData;
 
 
 #define OFFSET(x) offsetof(StabData, x)
 #define OFFSETC(x) (offsetof(StabData, conf)+offsetof(VSMotionDetectConfig, x))
 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 

 static const AVOption vidstabdetect_options[] = {

     {"result",      "path to the file used to write the transforms",                 OFFSET(result),             AV_OPT_TYPE_STRING, {.str = DEFAULT_RESULT_NAME}, .flags = FLAGS},

     {"shakiness",   "how shaky is the video and how quick is the camera?"

                     " 1: little (fast) 10: very strong/quick (slow)",                OFFSETC(shakiness),         AV_OPT_TYPE_INT,    {.i64 = 5},      1,  10, FLAGS},

     {"accuracy",    "(>=shakiness) 1: low 15: high (slow)",                          OFFSETC(accuracy),          AV_OPT_TYPE_INT,    {.i64 = 15},     1,  15, FLAGS},

     {"stepsize",    "region around minimum is scanned with 1 pixel resolution",      OFFSETC(stepSize),          AV_OPT_TYPE_INT,    {.i64 = 6},      1,  32, FLAGS},
     {"mincontrast", "below this contrast a field is discarded (0-1)",                OFFSETC(contrastThreshold), AV_OPT_TYPE_DOUBLE, {.dbl = 0.25}, 0.0, 1.0, FLAGS},
     {"show",        "0: draw nothing; 1,2: show fields and transforms",              OFFSETC(show),              AV_OPT_TYPE_INT,    {.i64 = 0},      0,   2, FLAGS},

     {"tripod",      "virtual tripod mode (if >0): motion is compared to a reference"

                     " reference frame (frame # is the value)",                       OFFSETC(virtualTripod),     AV_OPT_TYPE_INT,    {.i64 = 0}, 0, INT_MAX, FLAGS},

     {NULL}

 };
 
 AVFILTER_DEFINE_CLASS(vidstabdetect);
 
 static av_cold int init(AVFilterContext *ctx)
 {

     StabData *s = ctx->priv;

     ff_vs_init();

     s->class = &vidstabdetect_class;

     av_log(ctx, AV_LOG_VERBOSE, "vidstabdetect filter: init %s\n", LIBVIDSTAB_VERSION);
     return 0;
 }
 
 static av_cold void uninit(AVFilterContext *ctx)
 {

     StabData *s = ctx->priv;
     VSMotionDetect *md = &(s->md);

     if (s->f) {
         fclose(s->f);
         s->f = NULL;

     }
 
     vsMotionDetectionCleanup(md);
 }
 
 static int query_formats(AVFilterContext *ctx)
 {
     // If you add something here also add it in vidstabutils.c
     static const enum AVPixelFormat pix_fmts[] = {
         AV_PIX_FMT_YUV444P,  AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV420P,
         AV_PIX_FMT_YUV411P,  AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUVA420P,
         AV_PIX_FMT_YUV440P,  AV_PIX_FMT_GRAY8,
         AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24, AV_PIX_FMT_RGBA,
         AV_PIX_FMT_NONE
     };
 

     AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
     if (!fmts_list)
         return AVERROR(ENOMEM);
     return ff_set_common_formats(ctx, fmts_list);

 }
 
 static int config_input(AVFilterLink *inlink)
 {
     AVFilterContext *ctx = inlink->dst;

     StabData *s = ctx->priv;

     VSMotionDetect* md = &(s->md);

     VSFrameInfo fi;
     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
 

     vsFrameInfoInit(&fi, inlink->w, inlink->h,
                     ff_av2vs_pixfmt(ctx, inlink->format));

     if (fi.bytesPerPixel != av_get_bits_per_pixel(desc)/8) {

         av_log(ctx, AV_LOG_ERROR, "pixel-format error: wrong bits/per/pixel, please report a BUG");
         return AVERROR(EINVAL);
     }

     if (fi.log2ChromaW != desc->log2_chroma_w) {

         av_log(ctx, AV_LOG_ERROR, "pixel-format error: log2_chroma_w, please report a BUG");
         return AVERROR(EINVAL);
     }
 

     if (fi.log2ChromaH != desc->log2_chroma_h) {

         av_log(ctx, AV_LOG_ERROR, "pixel-format error: log2_chroma_h, please report a BUG");
         return AVERROR(EINVAL);
     }
 

     // set values that are not initialized by the options

     s->conf.algo     = 1;
     s->conf.modName  = "vidstabdetect";
     if (vsMotionDetectInit(md, &s->conf, &fi) != VS_OK) {

         av_log(ctx, AV_LOG_ERROR, "initialization of Motion Detection failed, please report a BUG");
         return AVERROR(EINVAL);
     }
 

     vsMotionDetectGetConfig(&s->conf, md);

     av_log(ctx, AV_LOG_INFO, "Video stabilization settings (pass 1/2):\n");

     av_log(ctx, AV_LOG_INFO, "     shakiness = %d\n", s->conf.shakiness);
     av_log(ctx, AV_LOG_INFO, "      accuracy = %d\n", s->conf.accuracy);
     av_log(ctx, AV_LOG_INFO, "      stepsize = %d\n", s->conf.stepSize);
     av_log(ctx, AV_LOG_INFO, "   mincontrast = %f\n", s->conf.contrastThreshold);
     av_log(ctx, AV_LOG_INFO, "        tripod = %d\n", s->conf.virtualTripod);
     av_log(ctx, AV_LOG_INFO, "          show = %d\n", s->conf.show);
     av_log(ctx, AV_LOG_INFO, "        result = %s\n", s->result);
 
     s->f = fopen(s->result, "w");
     if (s->f == NULL) {
         av_log(ctx, AV_LOG_ERROR, "cannot open transform file %s\n", s->result);

         return AVERROR(EINVAL);

     } else {

         if (vsPrepareFile(md, s->f) != VS_OK) {
             av_log(ctx, AV_LOG_ERROR, "cannot write to transform file %s\n", s->result);

             return AVERROR(EINVAL);
         }
     }
     return 0;
 }
 
 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
 {
     AVFilterContext *ctx = inlink->dst;

     StabData *s = ctx->priv;
     VSMotionDetect *md = &(s->md);

     LocalMotions localmotions;
 
     AVFilterLink *outlink = inlink->dst->outputs[0];
     VSFrame frame;
     int plane;
 

     if (s->conf.show > 0 && !av_frame_is_writable(in))

         av_frame_make_writable(in);

     for (plane = 0; plane < md->fi.planes; plane++) {

         frame.data[plane] = in->data[plane];
         frame.linesize[plane] = in->linesize[plane];
     }

     if (vsMotionDetection(md, &localmotions, &frame) != VS_OK) {

         av_log(ctx, AV_LOG_ERROR, "motion detection failed");
         return AVERROR(AVERROR_EXTERNAL);
     } else {

         if (vsWriteToFile(md, s->f, &localmotions) != VS_OK) {

             int ret = AVERROR(errno);

             av_log(ctx, AV_LOG_ERROR, "cannot write to transform file");

             return ret;

         }
         vs_vector_del(&localmotions);
     }
 

     return ff_filter_frame(outlink, in);

 }
 
 static const AVFilterPad avfilter_vf_vidstabdetect_inputs[] = {
     {

         .name         = "default",
         .type         = AVMEDIA_TYPE_VIDEO,
         .filter_frame = filter_frame,
         .config_props = config_input,

     },
     { NULL }
 };
 
 static const AVFilterPad avfilter_vf_vidstabdetect_outputs[] = {
     {

         .name = "default",
         .type = AVMEDIA_TYPE_VIDEO,

     },
     { NULL }
 };
 

 AVFilter ff_vf_vidstabdetect = {

     .name          = "vidstabdetect",

     .description   = NULL_IF_CONFIG_SMALL("Extract relative transformations, "
                                           "pass 1 of 2 for stabilization "
                                           "(see vidstabtransform for pass 2)."),

     .priv_size     = sizeof(StabData),
     .init          = init,
     .uninit        = uninit,
     .query_formats = query_formats,
     .inputs        = avfilter_vf_vidstabdetect_inputs,
     .outputs       = avfilter_vf_vidstabdetect_outputs,
     .priv_class    = &vidstabdetect_class,
 };