/*
  * Copyright (c) 2011 Stefano Sabatini
  *
  * 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
  * libSDL output device
  */
 
 #include <SDL.h>

 #include <SDL_thread.h>
 

 #include "libavutil/avstring.h"

 #include "libavutil/imgutils.h"

 #include "libavutil/opt.h"
 #include "libavutil/parseutils.h"
 #include "libavutil/pixdesc.h"

 #include "libavutil/time.h"

 #include "avdevice.h"
 
 typedef struct {
     AVClass *class;
     SDL_Surface *surface;
     SDL_Overlay *overlay;
     char *window_title;
     char *icon_title;

     int window_width,  window_height;  /**< size of the window */

     int window_fullscreen;

 
     SDL_Rect overlay_rect;

     int overlay_fmt;

     int sdl_was_already_inited;

     SDL_Thread *event_thread;
     SDL_mutex *mutex;
     SDL_cond *init_cond;
     int init_ret; /* return code used to signal initialization errors */
     int inited;
     int quit;

 } SDLContext;
 

 static const struct sdl_overlay_pix_fmt_entry {

     enum AVPixelFormat pix_fmt; int overlay_fmt;

 } sdl_overlay_pix_fmt_map[] = {

     { AV_PIX_FMT_YUV420P, SDL_IYUV_OVERLAY },
     { AV_PIX_FMT_YUYV422, SDL_YUY2_OVERLAY },
     { AV_PIX_FMT_UYVY422, SDL_UYVY_OVERLAY },
     { AV_PIX_FMT_NONE,    0                },

 };
 
 static int sdl_write_trailer(AVFormatContext *s)
 {
     SDLContext *sdl = s->priv_data;
 

     sdl->quit = 1;
 
     if (sdl->overlay)

         SDL_FreeYUVOverlay(sdl->overlay);

     sdl->overlay = NULL;

     if (sdl->event_thread)
         SDL_WaitThread(sdl->event_thread, NULL);

     sdl->event_thread = NULL;

     if (sdl->mutex)
         SDL_DestroyMutex(sdl->mutex);

     sdl->mutex = NULL;

     if (sdl->init_cond)
         SDL_DestroyCond(sdl->init_cond);

     sdl->init_cond = NULL;

     if (!sdl->sdl_was_already_inited)
         SDL_Quit();
 
     return 0;
 }
 

 static void compute_overlay_rect(AVFormatContext *s)
 {
     AVRational sar, dar; /* sample and display aspect ratios */
     SDLContext *sdl = s->priv_data;
     AVStream *st = s->streams[0];
     AVCodecContext *encctx = st->codec;
     SDL_Rect *overlay_rect = &sdl->overlay_rect;
 
     /* compute overlay width and height from the codec context information */
     sar = st->sample_aspect_ratio.num ? st->sample_aspect_ratio : (AVRational){ 1, 1 };
     dar = av_mul_q(sar, (AVRational){ encctx->width, encctx->height });
 
     /* we suppose the screen has a 1/1 sample aspect ratio */
     if (sdl->window_width && sdl->window_height) {
         /* fit in the window */
         if (av_cmp_q(dar, (AVRational){ sdl->window_width, sdl->window_height }) > 0) {
             /* fit in width */
             overlay_rect->w = sdl->window_width;
             overlay_rect->h = av_rescale(overlay_rect->w, dar.den, dar.num);
         } else {
             /* fit in height */
             overlay_rect->h = sdl->window_height;
             overlay_rect->w = av_rescale(overlay_rect->h, dar.num, dar.den);
         }
     } else {
         if (sar.num > sar.den) {
             overlay_rect->w = encctx->width;
             overlay_rect->h = av_rescale(overlay_rect->w, dar.den, dar.num);
         } else {
             overlay_rect->h = encctx->height;
             overlay_rect->w = av_rescale(overlay_rect->h, dar.num, dar.den);
         }
         sdl->window_width  = overlay_rect->w;
         sdl->window_height = overlay_rect->h;
     }
 
     overlay_rect->x = (sdl->window_width  - overlay_rect->w) / 2;
     overlay_rect->y = (sdl->window_height - overlay_rect->h) / 2;
 }
 

 #define SDL_BASE_FLAGS (SDL_SWSURFACE|SDL_RESIZABLE)
 

 static int event_thread(void *arg)
 {
     AVFormatContext *s = arg;
     SDLContext *sdl = s->priv_data;

     int flags = SDL_BASE_FLAGS | (sdl->window_fullscreen ? SDL_FULLSCREEN : 0);

     AVStream *st = s->streams[0];
     AVCodecContext *encctx = st->codec;
 
     /* initialization */
     if (SDL_Init(SDL_INIT_VIDEO) != 0) {
         av_log(s, AV_LOG_ERROR, "Unable to initialize SDL: %s\n", SDL_GetError());
         sdl->init_ret = AVERROR(EINVAL);
         goto init_end;
     }
 
     SDL_WM_SetCaption(sdl->window_title, sdl->icon_title);
     sdl->surface = SDL_SetVideoMode(sdl->window_width, sdl->window_height,
                                     24, flags);
     if (!sdl->surface) {
         av_log(sdl, AV_LOG_ERROR, "Unable to set video mode: %s\n", SDL_GetError());
         sdl->init_ret = AVERROR(EINVAL);
         goto init_end;
     }
 
     sdl->overlay = SDL_CreateYUVOverlay(encctx->width, encctx->height,
                                         sdl->overlay_fmt, sdl->surface);
     if (!sdl->overlay || sdl->overlay->pitches[0] < encctx->width) {
         av_log(s, AV_LOG_ERROR,
                "SDL does not support an overlay with size of %dx%d pixels\n",
                encctx->width, encctx->height);
         sdl->init_ret = AVERROR(EINVAL);
         goto init_end;
     }
 
     sdl->init_ret = 0;
     av_log(s, AV_LOG_VERBOSE, "w:%d h:%d fmt:%s -> w:%d h:%d\n",
            encctx->width, encctx->height, av_get_pix_fmt_name(encctx->pix_fmt),

            sdl->overlay_rect.w, sdl->overlay_rect.h);

 
 init_end:
     SDL_LockMutex(sdl->mutex);
     sdl->inited = 1;
     SDL_UnlockMutex(sdl->mutex);
     SDL_CondSignal(sdl->init_cond);
 
     if (sdl->init_ret < 0)
         return sdl->init_ret;
 
     /* event loop */
     while (!sdl->quit) {
         int ret;
         SDL_Event event;
         SDL_PumpEvents();
         ret = SDL_PeepEvents(&event, 1, SDL_GETEVENT, SDL_ALLEVENTS);

         if (ret < 0) {

             av_log(s, AV_LOG_ERROR, "Error when getting SDL event: %s\n", SDL_GetError());
             continue;

         }
         if (ret == 0) {
             SDL_Delay(10);
             continue;
         }

 
         switch (event.type) {
         case SDL_KEYDOWN:
             switch (event.key.keysym.sym) {
             case SDLK_ESCAPE:
             case SDLK_q:
                 sdl->quit = 1;
                 break;
             }
             break;
         case SDL_QUIT:
             sdl->quit = 1;
             break;

 
         case SDL_VIDEORESIZE:
             sdl->window_width  = event.resize.w;
             sdl->window_height = event.resize.h;
 
             SDL_LockMutex(sdl->mutex);
             sdl->surface = SDL_SetVideoMode(sdl->window_width, sdl->window_height, 24, SDL_BASE_FLAGS);
             if (!sdl->surface) {
                 av_log(s, AV_LOG_ERROR, "Failed to set SDL video mode: %s\n", SDL_GetError());
                 sdl->quit = 1;
             } else {
                 compute_overlay_rect(s);
             }
             SDL_UnlockMutex(sdl->mutex);
             break;
 

         default:
             break;
         }
     }
 
     return 0;
 }
 

 static int sdl_write_header(AVFormatContext *s)
 {
     SDLContext *sdl = s->priv_data;
     AVStream *st = s->streams[0];
     AVCodecContext *encctx = st->codec;
     int i, ret;
 

     if (!sdl->window_title)
         sdl->window_title = av_strdup(s->filename);

     if (!sdl->icon_title)
         sdl->icon_title = av_strdup(sdl->window_title);
 
     if (SDL_WasInit(SDL_INIT_VIDEO)) {
         av_log(s, AV_LOG_ERROR,

                "SDL video subsystem was already inited, aborting\n");

         sdl->sdl_was_already_inited = 1;
         ret = AVERROR(EINVAL);
         goto fail;
     }
 
     if (   s->nb_streams > 1
         || encctx->codec_type != AVMEDIA_TYPE_VIDEO

         || encctx->codec_id   != AV_CODEC_ID_RAWVIDEO) {

         av_log(s, AV_LOG_ERROR, "Only supports one rawvideo stream\n");
         ret = AVERROR(EINVAL);
         goto fail;
     }
 

     for (i = 0; sdl_overlay_pix_fmt_map[i].pix_fmt != AV_PIX_FMT_NONE; i++) {

         if (sdl_overlay_pix_fmt_map[i].pix_fmt == encctx->pix_fmt) {
             sdl->overlay_fmt = sdl_overlay_pix_fmt_map[i].overlay_fmt;
             break;
         }
     }
 
     if (!sdl->overlay_fmt) {
         av_log(s, AV_LOG_ERROR,

                "Unsupported pixel format '%s', choose one of yuv420p, yuyv422, or uyvy422\n",

                av_get_pix_fmt_name(encctx->pix_fmt));
         ret = AVERROR(EINVAL);
         goto fail;
     }
 
     /* compute overlay width and height from the codec context information */

     compute_overlay_rect(s);

     sdl->init_cond = SDL_CreateCond();
     if (!sdl->init_cond) {
         av_log(s, AV_LOG_ERROR, "Could not create SDL condition variable: %s\n", SDL_GetError());
         ret = AVERROR_EXTERNAL;

         goto fail;
     }

     sdl->mutex = SDL_CreateMutex();
     if (!sdl->mutex) {
         av_log(s, AV_LOG_ERROR, "Could not create SDL mutex: %s\n", SDL_GetError());
         ret = AVERROR_EXTERNAL;
         goto fail;
     }
     sdl->event_thread = SDL_CreateThread(event_thread, s);
     if (!sdl->event_thread) {
         av_log(s, AV_LOG_ERROR, "Could not create SDL event thread: %s\n", SDL_GetError());
         ret = AVERROR_EXTERNAL;

         goto fail;
     }
 

     /* wait until the video system has been inited */
     SDL_LockMutex(sdl->mutex);

     while (!sdl->inited) {

         SDL_CondWait(sdl->init_cond, sdl->mutex);
     }
     SDL_UnlockMutex(sdl->mutex);
     if (sdl->init_ret < 0) {
         ret = sdl->init_ret;
         goto fail;
     }

     return 0;
 
 fail:
     sdl_write_trailer(s);
     return ret;
 }
 
 static int sdl_write_packet(AVFormatContext *s, AVPacket *pkt)
 {
     SDLContext *sdl = s->priv_data;
     AVCodecContext *encctx = s->streams[0]->codec;

     uint8_t *data[4];
     int linesize[4];

     int i;
 

     if (sdl->quit) {
         sdl_write_trailer(s);

         return AVERROR(EIO);

     }

     av_image_fill_arrays(data, linesize, pkt->data, encctx->pix_fmt, encctx->width, encctx->height, 1);

     SDL_LockMutex(sdl->mutex);

     SDL_FillRect(sdl->surface, &sdl->surface->clip_rect,
                  SDL_MapRGB(sdl->surface->format, 0, 0, 0));
     SDL_LockYUVOverlay(sdl->overlay);
     for (i = 0; i < 3; i++) {

         sdl->overlay->pixels [i] = data    [i];
         sdl->overlay->pitches[i] = linesize[i];

     }

     SDL_DisplayYUVOverlay(sdl->overlay, &sdl->overlay_rect);

     SDL_UnlockYUVOverlay(sdl->overlay);
 

     SDL_UpdateRect(sdl->surface,
                    sdl->overlay_rect.x, sdl->overlay_rect.y,
                    sdl->overlay_rect.w, sdl->overlay_rect.h);

     SDL_UnlockMutex(sdl->mutex);

 
     return 0;
 }
 
 #define OFFSET(x) offsetof(SDLContext,x)
 
 static const AVOption options[] = {

     { "window_title", "set SDL window title",           OFFSET(window_title), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
     { "icon_title",   "set SDL iconified window title", OFFSET(icon_title)  , AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
     { "window_size",  "set SDL window forced size",     OFFSET(window_width), AV_OPT_TYPE_IMAGE_SIZE, { .str = NULL }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM },
     { "window_fullscreen", "set SDL window fullscreen", OFFSET(window_fullscreen), AV_OPT_TYPE_INT, { .i64 = 0 }, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM },

     { NULL },
 };
 
 static const AVClass sdl_class = {
     .class_name = "sdl outdev",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,

     .category   = AV_CLASS_CATEGORY_DEVICE_VIDEO_OUTPUT,

 };
 
 AVOutputFormat ff_sdl_muxer = {
     .name           = "sdl",
     .long_name      = NULL_IF_CONFIG_SMALL("SDL output device"),
     .priv_data_size = sizeof(SDLContext),

     .audio_codec    = AV_CODEC_ID_NONE,
     .video_codec    = AV_CODEC_ID_RAWVIDEO,

     .write_header   = sdl_write_header,
     .write_packet   = sdl_write_packet,
     .write_trailer  = sdl_write_trailer,

     .flags          = AVFMT_NOFILE | AVFMT_VARIABLE_FPS | AVFMT_NOTIMESTAMPS,

     .priv_class     = &sdl_class,
 };