#include <obs-module.h>
#include <util/deque.h>
#include <util/threading.h>
#include <util/platform.h>
#include <util/darray.h>
#include <util/dstr.h>
#include <util/task.h>

#include <inttypes.h>

#define do_log(level, format, ...)               \
	blog(level, "[slideshow: '%s'] " format, \
	     obs_source_get_name(ss->source), ##__VA_ARGS__)

#define warn(format, ...) do_log(LOG_WARNING, format, ##__VA_ARGS__)

/* clang-format off */

static const char *S_TR_SPEED                = "transition_speed";
static const char *S_CUSTOM_SIZE             = "use_custom_size";
static const char *S_SLIDE_TIME              = "slide_time";
static const char *S_TRANSITION              = "transition";
static const char *S_RANDOMIZE               = "randomize";
static const char *S_LOOP                    = "loop";
static const char *S_HIDE                    = "hide";
static const char *S_FILES                   = "files";
static const char *S_BEHAVIOR                = "playback_behavior";
static const char *S_BEHAVIOR_STOP_RESTART   = "stop_restart";
static const char *S_BEHAVIOR_PAUSE_UNPAUSE  = "pause_unpause";
static const char *S_BEHAVIOR_ALWAYS_PLAY    = "always_play";
static const char *S_MODE                    = "slide_mode";
static const char *S_MODE_AUTO               = "mode_auto";
static const char *S_MODE_MANUAL             = "mode_manual";

static const char *TR_CUT                    = "cut";
static const char *TR_FADE                   = "fade";
static const char *TR_SWIPE                  = "swipe";
static const char *TR_SLIDE                  = "slide";

#define T_(text) obs_module_text("SlideShow." text)
#define T_TR_SPEED                           T_("TransitionSpeed")
#define T_CUSTOM_SIZE                        T_("CustomSize")
#define T_SLIDE_TIME                         T_("SlideTime")
#define T_TRANSITION                         T_("Transition")
#define T_RANDOMIZE                          T_("Randomize")
#define T_LOOP                               T_("Loop")
#define T_HIDE                               T_("HideWhenDone")
#define T_FILES                              T_("Files")
#define T_BEHAVIOR                           T_("PlaybackBehavior")
#define T_BEHAVIOR_STOP_RESTART              T_("PlaybackBehavior.StopRestart")
#define T_BEHAVIOR_PAUSE_UNPAUSE             T_("PlaybackBehavior.PauseUnpause")
#define T_BEHAVIOR_ALWAYS_PLAY               T_("PlaybackBehavior.AlwaysPlay")
#define T_MODE                               T_("SlideMode")
#define T_MODE_AUTO                          T_("SlideMode.Auto")
#define T_MODE_MANUAL                        T_("SlideMode.Manual")

#define T_TR_(text) obs_module_text("SlideShow.Transition." text)
#define T_TR_CUT                             T_TR_("Cut")
#define T_TR_FADE                            T_TR_("Fade")
#define T_TR_SWIPE                           T_TR_("Swipe")
#define T_TR_SLIDE                           T_TR_("Slide")

/* clang-format on */

extern void image_source_preload_image(void *data);

/* ------------------------------------------------------------------------- */

struct image_file_data {
	char *path;
};

struct source_data {
	size_t slide_idx;
	const char *path;
	obs_source_t *source;
};

typedef DARRAY(struct image_file_data) image_file_array_t;

enum behavior {
	BEHAVIOR_STOP_RESTART,
	BEHAVIOR_PAUSE_UNPAUSE,
	BEHAVIOR_ALWAYS_PLAY,
};

#define SLIDE_BUFFER_COUNT 5

struct active_slides {
	struct deque prev;
	struct deque next;
	struct source_data cur;
};

struct slideshow_data {
	struct active_slides slides;
	image_file_array_t files;
	float slide_time;
	uint32_t tr_speed;
	const char *tr_name;
	bool manual;
	bool randomize;
	bool loop;
	bool restart_on_activate;
	bool pause_on_deactivate;
	bool restart;
	bool hide;
	bool use_cut;
	bool paused;
	bool stop;
	calldata_t cd;
	float elapsed;
	enum behavior behavior;

	enum obs_media_state state;
};

struct slideshow {
	obs_source_t *source;

	struct slideshow_data data;
	os_task_queue_t *queue;
	obs_source_t *transition;
	uint32_t cx;
	uint32_t cy;

	obs_hotkey_id play_pause_hotkey;
	obs_hotkey_id restart_hotkey;
	obs_hotkey_id stop_hotkey;
	obs_hotkey_id next_hotkey;
	obs_hotkey_id prev_hotkey;
};

static void set_media_state(void *data, enum obs_media_state state)
{
	struct slideshow *ss = data;
	ss->data.state = state;
}

static enum obs_media_state ss_get_state(void *data)
{
	struct slideshow *ss = data;
	return ss->data.state;
}

static inline obs_source_t *get_transition(struct slideshow *ss)
{
	return obs_source_get_ref(ss->transition);
}

static inline void free_source_data(struct source_data *sd)
{
	obs_source_release(sd->source);
}

static void free_active_slides(struct active_slides *slides)
{
	while (slides->prev.size) {
		struct source_data file;
		deque_pop_front(&slides->prev, &file, sizeof(file));
		free_source_data(&file);
	}

	while (slides->next.size) {
		struct source_data file;
		deque_pop_front(&slides->next, &file, sizeof(file));
		free_source_data(&file);
	}

	free_source_data(&slides->cur);

	deque_free(&slides->prev);
	deque_free(&slides->next);
}

static inline void free_slideshow_data(struct slideshow_data *ssd)
{
	free_active_slides(&ssd->slides);
	for (size_t i = 0; i < ssd->files.num; i++)
		bfree(ssd->files.array[i].path);
	calldata_free(&ssd->cd);
	da_free(ssd->files);
}

static size_t random_file(struct slideshow_data *ssd, size_t slide_idx)
{
	const size_t files = ssd->files.num;
	size_t next = slide_idx;

	if (ssd->files.num > 1) {
		while (next == slide_idx) {
			size_t threshold = (~files + 1) % files;
			size_t r;
			do {
				r = rand();
			} while (r < threshold);
			next = r % files;
		}
	}

	return next;
}

/* gets a new file idx based upon a prior index */
static inline size_t get_new_file(struct slideshow_data *ssd, size_t slide_idx,
				  bool next)
{
	if (ssd->randomize) {
		return random_file(ssd, slide_idx);
	} else if (next) {
		return (++slide_idx >= ssd->files.num) ? 0 : slide_idx;
	} else {
		return (slide_idx == 0) ? ssd->files.num - 1 : slide_idx - 1;
	}
}

/* ------------------------------------------------------------------------- */

static const char *ss_getname(void *unused)
{
	UNUSED_PARAMETER(unused);
	return obs_module_text("SlideShow");
}

/* adds a new file to the files list. used only in update */
static inline void add_file(image_file_array_t *new_files, const char *path)
{
	struct image_file_data data;
	data.path = bstrdup(path);
	da_push_back(*new_files, &data);
}

extern bool valid_extension(const char *ext);

/* transition to new source. assumes cur has already been set to new file */
static void do_transition(void *data, bool to_null)
{
	struct slideshow *ss = data;
	struct slideshow_data *ssd = &ss->data;
	bool valid = !!ss->data.files.num;

	if (valid && ssd->use_cut) {
		obs_transition_set(ss->transition, ssd->slides.cur.source);

	} else if (valid && !to_null) {
		obs_transition_start(ss->transition, OBS_TRANSITION_MODE_AUTO,
				     ssd->tr_speed, ssd->slides.cur.source);

	} else {
		obs_transition_start(ss->transition, OBS_TRANSITION_MODE_AUTO,
				     ssd->tr_speed, NULL);
		set_media_state(ss, OBS_MEDIA_STATE_ENDED);
		obs_source_media_ended(ss->source);
	}

	if (valid && !to_null) {
		calldata_set_int(&ssd->cd, "index", ssd->slides.cur.slide_idx);
		calldata_set_string(&ssd->cd, "path", ssd->slides.cur.path);

		signal_handler_t *sh =
			obs_source_get_signal_handler(ss->source);
		signal_handler_signal(sh, "slide_changed", &ssd->cd);
	}
}

/* get a source via its slide idx in one of slideshow_data's deques. *
 * only used in get_new_source().                                        */
static inline struct source_data *deque_get_source(struct deque *buf,
						   size_t slide_idx)
{
	struct source_data *cur;
	size_t count = buf->size / sizeof(*cur);

	for (size_t i = 0; i < count; i++) {
		cur = deque_data(buf, i * sizeof(struct source_data));
		if (cur->slide_idx == slide_idx)
			return cur;
	}

	return NULL;
}

static void decode_image(void *data)
{
	obs_weak_source_t *weak = data;

	obs_source_t *source = obs_weak_source_get_source(weak);
	if (source) {
		image_source_preload_image(obs_obj_get_data(source));
		obs_source_release(source);
	}

	obs_weak_source_release(weak);
}

/* creates source from a file path. only used in get_new_source(). */
static inline obs_source_t *create_source_from_file(struct slideshow *ss,
						    const char *file, bool now)
{
	obs_data_t *settings = obs_data_create();
	obs_source_t *source;

	obs_data_set_string(settings, "file", file);
	obs_data_set_bool(settings, "unload", false);
	obs_data_set_bool(settings, "is_slide", !now);
	source = obs_source_create_private("image_source", NULL, settings);

	obs_data_release(settings);

	os_task_queue_queue_task(ss->queue, decode_image,
				 obs_source_get_weak_source(source));

	return source;
}

/* searches the active slides for the same slide so we can reuse existing *
 * sources                                                                */
static struct source_data *find_existing_source(struct active_slides *as,
						size_t slide_idx)
{
	struct source_data *psd;

	if (as->cur.source && as->cur.slide_idx == slide_idx)
		return &as->cur;

	psd = deque_get_source(&as->prev, slide_idx);
	if (psd)
		return psd;

	psd = deque_get_source(&as->next, slide_idx);
	return psd;
}

/* get a new source_data structure and reuse existing sources if possible. *
 * use the 'new' parameter if you want to create a brand new list of       *
 * active sources while still reusing the old list as well.                */
static struct source_data get_new_source(struct slideshow *ss,
					 struct active_slides *new,
					 size_t slide_idx)
{
	struct slideshow_data *ssd = &ss->data;
	struct source_data *psd;
	struct source_data sd;

	/* ----------------------------------------------- */
	/* use existing source if we already have it       */

	psd = find_existing_source(&ssd->slides, slide_idx);
	if (psd) {
		sd = *psd;
		sd.source = obs_source_get_ref(sd.source);
		if (sd.source) {
			return sd;
		}
	}

	if (new) {
		psd = find_existing_source(new, slide_idx);
		if (psd) {
			sd = *psd;
			sd.source = obs_source_get_ref(sd.source);
			if (sd.source) {
				return sd;
			}
		}
	}

	/* ----------------------------------------------- */
	/* and then create a new one if we don't           */

	sd.path = ssd->files.array[slide_idx].path;
	sd.slide_idx = slide_idx;
	sd.source = create_source_from_file(ss, sd.path, false);
	return sd;
}

static void restart_slides(struct slideshow *ss)
{
	struct slideshow_data *ssd = &ss->data;
	size_t start_idx = 0;

	if (ssd->randomize && ssd->files.num > 0) {
		start_idx = (size_t)rand() % ssd->files.num;
	}

	struct active_slides new_slides = {0};

	if (ssd->files.num) {
		struct source_data sd;
		size_t idx;

		new_slides.cur = get_new_source(ss, &new_slides, start_idx);

		idx = start_idx;
		for (size_t i = 0; i < SLIDE_BUFFER_COUNT; i++) {
			idx = get_new_file(ssd, idx, true);
			sd = get_new_source(ss, &new_slides, idx);
			deque_push_back(&new_slides.next, &sd, sizeof(sd));
		}

		idx = start_idx;
		for (size_t i = 0; i < SLIDE_BUFFER_COUNT; i++) {
			idx = get_new_file(ssd, idx, false);
			sd = get_new_source(ss, &new_slides, idx);
			deque_push_front(&new_slides.prev, &sd, sizeof(sd));
		}
	}

	free_active_slides(&ssd->slides);
	ssd->slides = new_slides;
}

static void ss_update(void *data, obs_data_t *settings)
{
	struct slideshow *ss = data;
	struct slideshow_data new_data = {0};
	struct slideshow_data old_data = ss->data;
	obs_data_array_t *array;
	obs_source_t *new_tr = NULL;
	obs_source_t *old_tr = NULL;
	uint32_t new_duration;
	uint32_t cx = 0;
	uint32_t cy = 0;
	size_t count;
	const char *behavior;
	const char *tr_name;
	const char *mode;

	/* ------------------------------------- */
	/* get settings data                     */

	behavior = obs_data_get_string(settings, S_BEHAVIOR);

	if (astrcmpi(behavior, S_BEHAVIOR_PAUSE_UNPAUSE) == 0)
		new_data.behavior = BEHAVIOR_PAUSE_UNPAUSE;
	else if (astrcmpi(behavior, S_BEHAVIOR_ALWAYS_PLAY) == 0)
		new_data.behavior = BEHAVIOR_ALWAYS_PLAY;
	else /* S_BEHAVIOR_STOP_RESTART */
		new_data.behavior = BEHAVIOR_STOP_RESTART;

	mode = obs_data_get_string(settings, S_MODE);

	new_data.manual = (astrcmpi(mode, S_MODE_MANUAL) == 0);

	tr_name = obs_data_get_string(settings, S_TRANSITION);
	if (astrcmpi(tr_name, TR_CUT) == 0)
		tr_name = "cut_transition";
	else if (astrcmpi(tr_name, TR_SWIPE) == 0)
		tr_name = "swipe_transition";
	else if (astrcmpi(tr_name, TR_SLIDE) == 0)
		tr_name = "slide_transition";
	else
		tr_name = "fade_transition";

	new_data.randomize = obs_data_get_bool(settings, S_RANDOMIZE);
	new_data.loop = obs_data_get_bool(settings, S_LOOP);
	new_data.hide = obs_data_get_bool(settings, S_HIDE);

	if (!old_data.tr_name || strcmp(tr_name, old_data.tr_name) != 0)
		new_tr = obs_source_create_private(tr_name, NULL, NULL);

	new_duration = (uint32_t)obs_data_get_int(settings, S_SLIDE_TIME);
	new_data.tr_speed = (uint32_t)obs_data_get_int(settings, S_TR_SPEED);

	array = obs_data_get_array(settings, S_FILES);
	count = obs_data_array_count(array);

	if (strcmp(tr_name, "cut_transition") != 0) {
		if (new_duration < 100)
			new_duration = 100;

		new_duration += new_data.tr_speed;
	} else {
		if (new_duration < 50)
			new_duration = 50;
	}

	new_data.slide_time = (float)new_duration / 1000.0f;

	/* ------------------------------------- */
	/* create new list of sources            */

	for (size_t i = 0; i < count; i++) {
		obs_data_t *item = obs_data_array_item(array, i);
		const char *path = obs_data_get_string(item, "value");
		os_dir_t *dir = os_opendir(path);

		if (!path || !*path) {
			obs_data_release(item);
			continue;
		}

		if (dir) {
			struct dstr dir_path = {0};
			struct os_dirent *ent;

			for (;;) {
				const char *ext;

				ent = os_readdir(dir);
				if (!ent)
					break;
				if (ent->directory)
					continue;

				ext = os_get_path_extension(ent->d_name);
				if (!valid_extension(ext))
					continue;

				dstr_copy(&dir_path, path);
				dstr_cat_ch(&dir_path, '/');
				dstr_cat(&dir_path, ent->d_name);
				add_file(&new_data.files, dir_path.array);
			}

			dstr_free(&dir_path);
			os_closedir(dir);
		} else {
			add_file(&new_data.files, path);
		}

		obs_data_release(item);
	}

	/* ------------------------------------- */
	/* get new size                          */

	const char *res_str = obs_data_get_string(settings, S_CUSTOM_SIZE);
	bool valid = false;

	int ret = sscanf(res_str, "%" PRIu32 "x%" PRIu32, &cx, &cy);
	if (ret == 2) {
		valid = true;
	} else {
		cx = 0;
		cy = 0;
	}

	/* ------------------------------------- */
	/* update settings data                  */

	ss->data = new_data;
	if (new_tr) {
		old_tr = ss->transition;
		ss->transition = new_tr;
	}

	/* ------------------------------------- */
	/* clean up                              */

	if (old_tr)
		obs_source_release(old_tr);
	free_slideshow_data(&old_data);

	/* ------------------------------------- */
	/* update files                          */

	restart_slides(ss);

	/* ------------------------------------- */
	/* restart transition                    */

	ss->cx = cx;
	ss->cy = cy;
	obs_transition_set_size(ss->transition, cx, cy);
	obs_transition_set_alignment(ss->transition, OBS_ALIGN_CENTER);
	obs_transition_set_scale_type(ss->transition,
				      OBS_TRANSITION_SCALE_ASPECT);

	if (new_tr)
		obs_source_add_active_child(ss->source, new_tr);
	if (ss->data.files.num) {
		do_transition(ss, false);

		if (ss->data.manual)
			set_media_state(ss, OBS_MEDIA_STATE_PAUSED);
		else
			set_media_state(ss, OBS_MEDIA_STATE_PLAYING);

		obs_source_media_started(ss->source);
	}

	obs_data_array_release(array);
}

static void ss_play_pause(void *data, bool pause)
{
	struct slideshow *ss = data;

	if (ss->data.stop) {
		ss->data.stop = false;
		ss->data.paused = false;
		do_transition(ss, false);
	} else {
		ss->data.paused = pause;
		ss->data.manual = pause;
	}

	if (pause)
		set_media_state(ss, OBS_MEDIA_STATE_PAUSED);
	else
		set_media_state(ss, OBS_MEDIA_STATE_PLAYING);
}

static void ss_restart(void *data)
{
	struct slideshow *ss = data;

	restart_slides(ss);
	ss->data.elapsed = 0.0f;
	ss->data.stop = false;
	ss->data.paused = false;
	do_transition(ss, false);

	set_media_state(ss, OBS_MEDIA_STATE_PLAYING);
}

static void ss_stop(void *data)
{
	struct slideshow *ss = data;

	restart_slides(ss);
	ss->data.elapsed = 0.0f;
	ss->data.stop = true;
	ss->data.paused = false;
	do_transition(ss, true);

	set_media_state(ss, OBS_MEDIA_STATE_STOPPED);
}

static void ss_next_slide(void *data)
{
	struct slideshow *ss = data;
	struct slideshow_data *ssd = &ss->data;
	struct active_slides *slides = &ssd->slides;
	struct source_data sd;

	if (!ssd->files.num || obs_transition_get_time(ss->transition) < 1.0f)
		return;

	struct source_data *last = deque_data(
		&slides->next, (SLIDE_BUFFER_COUNT - 1) * sizeof(sd));

	size_t slide_idx = last->slide_idx;
	if (ss->data.randomize)
		slide_idx = random_file(&ss->data, slide_idx);
	else if (++slide_idx >= ssd->files.num)
		slide_idx = 0;

	sd = get_new_source(ss, NULL, slide_idx);
	deque_push_back(&slides->next, &sd, sizeof(sd));
	deque_push_back(&slides->prev, &slides->cur, sizeof(sd));
	deque_pop_front(&slides->next, &slides->cur, sizeof(sd));
	deque_pop_front(&slides->prev, &sd, sizeof(sd));
	free_source_data(&sd);

	do_transition(ss, false);
}

static void ss_previous_slide(void *data)
{
	struct slideshow *ss = data;
	struct slideshow_data *ssd = &ss->data;
	struct active_slides *slides = &ssd->slides;
	struct source_data sd;

	if (!ssd->files.num || obs_transition_get_time(ss->transition) < 1.0f)
		return;

	struct source_data *first = deque_data(&slides->prev, 0);

	size_t slide_idx = first->slide_idx;
	if (ss->data.randomize)
		slide_idx = random_file(&ss->data, slide_idx);
	else if (slide_idx == 0)
		slide_idx = ss->data.files.num - 1;
	else
		--slide_idx;

	sd = get_new_source(ss, NULL, slide_idx);
	deque_push_front(&slides->prev, &sd, sizeof(sd));
	deque_push_front(&slides->next, &slides->cur, sizeof(sd));
	deque_pop_back(&slides->prev, &slides->cur, sizeof(sd));
	deque_pop_back(&slides->next, &sd, sizeof(sd));
	free_source_data(&sd);

	do_transition(ss, false);
}

static void play_pause_hotkey(void *data, obs_hotkey_id id,
			      obs_hotkey_t *hotkey, bool pressed)
{
	UNUSED_PARAMETER(id);
	UNUSED_PARAMETER(hotkey);

	struct slideshow *ss = data;

	if (pressed && obs_source_showing(ss->source))
		obs_source_media_play_pause(ss->source, !ss->data.paused);
}

static void restart_hotkey(void *data, obs_hotkey_id id, obs_hotkey_t *hotkey,
			   bool pressed)
{
	UNUSED_PARAMETER(id);
	UNUSED_PARAMETER(hotkey);

	struct slideshow *ss = data;

	if (pressed && obs_source_showing(ss->source))
		obs_source_media_restart(ss->source);
}

static void stop_hotkey(void *data, obs_hotkey_id id, obs_hotkey_t *hotkey,
			bool pressed)
{
	UNUSED_PARAMETER(id);
	UNUSED_PARAMETER(hotkey);

	struct slideshow *ss = data;

	if (pressed && obs_source_showing(ss->source))
		obs_source_media_stop(ss->source);
}

static void next_slide_hotkey(void *data, obs_hotkey_id id,
			      obs_hotkey_t *hotkey, bool pressed)
{
	UNUSED_PARAMETER(id);
	UNUSED_PARAMETER(hotkey);

	struct slideshow *ss = data;

	if (!ss->data.manual)
		return;

	if (pressed && obs_source_showing(ss->source))
		obs_source_media_next(ss->source);
}

static void previous_slide_hotkey(void *data, obs_hotkey_id id,
				  obs_hotkey_t *hotkey, bool pressed)
{
	UNUSED_PARAMETER(id);
	UNUSED_PARAMETER(hotkey);

	struct slideshow *ss = data;

	if (!ss->data.manual)
		return;

	if (pressed && obs_source_showing(ss->source))
		obs_source_media_previous(ss->source);
}

static void current_slide_proc(void *data, calldata_t *cd)
{
	struct slideshow *ss = data;
	calldata_set_int(cd, "current_index", ss->data.slides.cur.slide_idx);
}

static void total_slides_proc(void *data, calldata_t *cd)
{
	struct slideshow *ss = data;
	calldata_set_int(cd, "total_files", ss->data.files.num);
}

static void ss_destroy(void *data)
{
	struct slideshow *ss = data;

	os_task_queue_destroy(ss->queue);
	obs_source_release(ss->transition);
	free_slideshow_data(&ss->data);
	bfree(ss);
}

static void *ss_create(obs_data_t *settings, obs_source_t *source)
{
	struct slideshow *ss = bzalloc(sizeof(*ss));
	proc_handler_t *ph = obs_source_get_proc_handler(source);

	ss->source = source;

	ss->data.manual = false;
	ss->data.paused = false;
	ss->data.stop = false;

	ss->queue = os_task_queue_create();

	ss->play_pause_hotkey = obs_hotkey_register_source(
		source, "SlideShow.PlayPause",
		obs_module_text("SlideShow.PlayPause"), play_pause_hotkey, ss);

	ss->restart_hotkey = obs_hotkey_register_source(
		source, "SlideShow.Restart",
		obs_module_text("SlideShow.Restart"), restart_hotkey, ss);

	ss->stop_hotkey = obs_hotkey_register_source(
		source, "SlideShow.Stop", obs_module_text("SlideShow.Stop"),
		stop_hotkey, ss);

	ss->next_hotkey = obs_hotkey_register_source(
		source, "SlideShow.NextSlide",
		obs_module_text("SlideShow.NextSlide"), next_slide_hotkey, ss);

	ss->prev_hotkey = obs_hotkey_register_source(
		source, "SlideShow.PreviousSlide",
		obs_module_text("SlideShow.PreviousSlide"),
		previous_slide_hotkey, ss);

	proc_handler_add(ph, "void current_index(out int current_index)",
			 current_slide_proc, ss);
	proc_handler_add(ph, "void total_files(out int total_files)",
			 total_slides_proc, ss);

	signal_handler_t *sh = obs_source_get_signal_handler(ss->source);
	signal_handler_add(sh, "void slide_changed(int index, string path)");

	obs_source_update(source, NULL);

	UNUSED_PARAMETER(settings);
	return ss;
}

static void ss_video_render(void *data, gs_effect_t *effect)
{
	struct slideshow *ss = data;
	obs_source_t *transition = get_transition(ss);

	if (transition) {
		obs_source_video_render(transition);
		obs_source_release(transition);
	}

	UNUSED_PARAMETER(effect);
}

static void ss_video_tick(void *data, float seconds)
{
	struct slideshow *ss = data;
	struct slideshow_data *ssd = &ss->data;

	if (!ss->transition || !ssd->slide_time)
		return;

	if (ssd->restart_on_activate && ssd->use_cut) {
		ssd->elapsed = 0.0f;
		restart_slides(ss);
		do_transition(ss, false);
		ssd->restart_on_activate = false;
		ssd->use_cut = false;
		ssd->stop = false;
		return;
	}

	if (ssd->pause_on_deactivate || ssd->manual || ssd->stop || ssd->paused)
		return;

	/* ----------------------------------------------------- */
	/* fade to transparency when the file list becomes empty */
	if (!ssd->files.num) {
		obs_source_t *active_transition_source =
			obs_transition_get_active_source(ss->transition);

		if (active_transition_source) {
			obs_source_release(active_transition_source);
			do_transition(ss, true);
		}
	}

	/* ----------------------------------------------------- */
	/* do transition when slide time reached                 */
	ssd->elapsed += seconds;

	if (ssd->elapsed > ssd->slide_time) {
		ssd->elapsed -= ssd->slide_time;

		if (!ssd->loop &&
		    ssd->slides.cur.slide_idx == ssd->files.num - 1) {
			if (ssd->hide)
				do_transition(ss, true);
			else
				do_transition(ss, false);

			return;
		}

		obs_source_media_next(ss->source);
	}
}

static inline bool ss_audio_render_(obs_source_t *transition, uint64_t *ts_out,
				    struct obs_source_audio_mix *audio_output,
				    uint32_t mixers, size_t channels,
				    size_t sample_rate)
{
	struct obs_source_audio_mix child_audio;
	uint64_t source_ts;

	if (obs_source_audio_pending(transition))
		return false;

	source_ts = obs_source_get_audio_timestamp(transition);
	if (!source_ts)
		return false;

	obs_source_get_audio_mix(transition, &child_audio);
	for (size_t mix = 0; mix < MAX_AUDIO_MIXES; mix++) {
		if ((mixers & (1 << mix)) == 0)
			continue;

		for (size_t ch = 0; ch < channels; ch++) {
			float *out = audio_output->output[mix].data[ch];
			float *in = child_audio.output[mix].data[ch];

			memcpy(out, in, AUDIO_OUTPUT_FRAMES * sizeof(float));
		}
	}

	*ts_out = source_ts;

	UNUSED_PARAMETER(sample_rate);
	return true;
}

static bool ss_audio_render(void *data, uint64_t *ts_out,
			    struct obs_source_audio_mix *audio_output,
			    uint32_t mixers, size_t channels,
			    size_t sample_rate)
{
	struct slideshow *ss = data;
	obs_source_t *transition = get_transition(ss);
	bool success;

	if (!transition)
		return false;

	success = ss_audio_render_(transition, ts_out, audio_output, mixers,
				   channels, sample_rate);

	obs_source_release(transition);
	return success;
}

static void ss_enum_sources(void *data, obs_source_enum_proc_t cb, void *param)
{
	struct slideshow *ss = data;

	if (ss->transition)
		cb(ss->source, ss->transition, param);
}

static uint32_t ss_width(void *data)
{
	struct slideshow *ss = data;
	return ss->transition ? ss->cx : 0;
}

static uint32_t ss_height(void *data)
{
	struct slideshow *ss = data;
	return ss->transition ? ss->cy : 0;
}

static void ss_defaults(obs_data_t *settings)
{
	obs_data_set_default_string(settings, S_TRANSITION, "fade");
	obs_data_set_default_int(settings, S_SLIDE_TIME, 2000); //8000);
	obs_data_set_default_int(settings, S_TR_SPEED, 700);
	obs_data_set_default_string(settings, S_CUSTOM_SIZE, "1920x1080");
	obs_data_set_default_string(settings, S_BEHAVIOR,
				    S_BEHAVIOR_ALWAYS_PLAY);
	obs_data_set_default_string(settings, S_MODE, S_MODE_AUTO);
	obs_data_set_default_bool(settings, S_LOOP, true);
}

static const char *file_filter = "Image files (*.bmp *.tga *.png *.jpeg *.jpg"
#ifdef _WIN32
				 " *.jxr"
#endif
				 " *.gif *.webp)";

static obs_properties_t *ss_properties(void *data)
{
	obs_properties_t *ppts = obs_properties_create();
	struct slideshow *ss = data;
	struct obs_video_info ovi;
	struct dstr path = {0};
	obs_property_t *p;
	int cx;
	int cy;

	/* ----------------- */

	obs_get_video_info(&ovi);
	cx = (int)ovi.base_width;
	cy = (int)ovi.base_height;

	/* ----------------- */

	p = obs_properties_add_list(ppts, S_BEHAVIOR, T_BEHAVIOR,
				    OBS_COMBO_TYPE_LIST,
				    OBS_COMBO_FORMAT_STRING);
	obs_property_list_add_string(p, T_BEHAVIOR_ALWAYS_PLAY,
				     S_BEHAVIOR_ALWAYS_PLAY);
	obs_property_list_add_string(p, T_BEHAVIOR_STOP_RESTART,
				     S_BEHAVIOR_STOP_RESTART);
	obs_property_list_add_string(p, T_BEHAVIOR_PAUSE_UNPAUSE,
				     S_BEHAVIOR_PAUSE_UNPAUSE);

	p = obs_properties_add_list(ppts, S_MODE, T_MODE, OBS_COMBO_TYPE_LIST,
				    OBS_COMBO_FORMAT_STRING);
	obs_property_list_add_string(p, T_MODE_AUTO, S_MODE_AUTO);
	obs_property_list_add_string(p, T_MODE_MANUAL, S_MODE_MANUAL);

	p = obs_properties_add_list(ppts, S_TRANSITION, T_TRANSITION,
				    OBS_COMBO_TYPE_LIST,
				    OBS_COMBO_FORMAT_STRING);
	obs_property_list_add_string(p, T_TR_CUT, TR_CUT);
	obs_property_list_add_string(p, T_TR_FADE, TR_FADE);
	obs_property_list_add_string(p, T_TR_SWIPE, TR_SWIPE);
	obs_property_list_add_string(p, T_TR_SLIDE, TR_SLIDE);

	p = obs_properties_add_int(ppts, S_SLIDE_TIME, T_SLIDE_TIME, 50,
				   3600000, 50);
	obs_property_int_set_suffix(p, " ms");

	p = obs_properties_add_int(ppts, S_TR_SPEED, T_TR_SPEED, 0, 3600000,
				   50);
	obs_property_int_set_suffix(p, " ms");

	obs_properties_add_bool(ppts, S_LOOP, T_LOOP);
	obs_properties_add_bool(ppts, S_HIDE, T_HIDE);
	obs_properties_add_bool(ppts, S_RANDOMIZE, T_RANDOMIZE);

	p = obs_properties_add_list(ppts, S_CUSTOM_SIZE, T_CUSTOM_SIZE,
				    OBS_COMBO_TYPE_EDITABLE,
				    OBS_COMBO_FORMAT_STRING);

	char str[32];
	snprintf(str, sizeof(str), "%dx%d", cx, cy);
	obs_property_list_add_string(p, str, str);

	if (ss) {
		if (ss->data.files.num) {
			struct image_file_data *last = da_end(ss->data.files);
			const char *slash;

			dstr_copy(&path, last->path);
			dstr_replace(&path, "\\", "/");
			slash = strrchr(path.array, '/');
			if (slash)
				dstr_resize(&path, slash - path.array + 1);
		}
	}

	obs_properties_add_editable_list(ppts, S_FILES, T_FILES,
					 OBS_EDITABLE_LIST_TYPE_FILES,
					 file_filter, path.array);
	dstr_free(&path);

	return ppts;
}

static void ss_activate(void *data)
{
	struct slideshow *ss = data;

	if (ss->data.behavior == BEHAVIOR_STOP_RESTART) {
		ss->data.restart_on_activate = true;
		ss->data.use_cut = true;
		set_media_state(ss, OBS_MEDIA_STATE_PLAYING);
	} else if (ss->data.behavior == BEHAVIOR_PAUSE_UNPAUSE) {
		ss->data.pause_on_deactivate = false;
		set_media_state(ss, OBS_MEDIA_STATE_PLAYING);
	}
}

static void ss_deactivate(void *data)
{
	struct slideshow *ss = data;

	if (ss->data.behavior == BEHAVIOR_PAUSE_UNPAUSE) {
		ss->data.pause_on_deactivate = true;
		set_media_state(ss, OBS_MEDIA_STATE_PAUSED);
	}
}

static void missing_file_callback(void *src, const char *new_path, void *data)
{
	struct slideshow *s = src;
	const char *orig_path = data;

	obs_source_t *source = s->source;
	obs_data_t *settings = obs_source_get_settings(source);
	obs_data_array_t *files = obs_data_get_array(settings, S_FILES);

	size_t l = obs_data_array_count(files);
	for (size_t i = 0; i < l; i++) {
		obs_data_t *file = obs_data_array_item(files, i);
		const char *path = obs_data_get_string(file, "value");

		if (strcmp(path, orig_path) == 0) {
			if (new_path && *new_path)
				obs_data_set_string(file, "value", new_path);
			else
				obs_data_array_erase(files, i);

			obs_data_release(file);
			break;
		}

		obs_data_release(file);
	}

	obs_source_update(source, settings);

	obs_data_array_release(files);
	obs_data_release(settings);
}

static obs_missing_files_t *ss_missingfiles(void *data)
{
	struct slideshow *s = data;
	obs_missing_files_t *missing_files = obs_missing_files_create();

	obs_source_t *source = s->source;
	obs_data_t *settings = obs_source_get_settings(source);
	obs_data_array_t *files = obs_data_get_array(settings, S_FILES);

	size_t l = obs_data_array_count(files);
	for (size_t i = 0; i < l; i++) {
		obs_data_t *item = obs_data_array_item(files, i);
		const char *path = obs_data_get_string(item, "value");

		if (*path != 0) {
			if (!os_file_exists(path)) {
				obs_missing_file_t *file =
					obs_missing_file_create(
						path, missing_file_callback,
						OBS_MISSING_FILE_SOURCE, source,
						(void *)path);

				obs_missing_files_add_file(missing_files, file);
			}
		}

		obs_data_release(item);
	}

	obs_data_array_release(files);
	obs_data_release(settings);

	return missing_files;
}

static enum gs_color_space
ss_video_get_color_space(void *data, size_t count,
			 const enum gs_color_space *preferred_spaces)
{
	enum gs_color_space space = GS_CS_SRGB;

	struct slideshow *ss = data;
	obs_source_t *transition = get_transition(ss);
	if (transition) {
		space = obs_source_get_color_space(transition, count,
						   preferred_spaces);
		obs_source_release(transition);
	}

	return space;
}

struct obs_source_info slideshow_info_mk2 = {
	.id = "slideshow",
	.version = 2,
	.type = OBS_SOURCE_TYPE_INPUT,
	.output_flags = OBS_SOURCE_VIDEO | OBS_SOURCE_CUSTOM_DRAW |
			OBS_SOURCE_COMPOSITE | OBS_SOURCE_CONTROLLABLE_MEDIA,
	.get_name = ss_getname,
	.create = ss_create,
	.destroy = ss_destroy,
	.update = ss_update,
	.activate = ss_activate,
	.deactivate = ss_deactivate,
	.video_render = ss_video_render,
	.video_tick = ss_video_tick,
	.audio_render = ss_audio_render,
	.enum_active_sources = ss_enum_sources,
	.get_width = ss_width,
	.get_height = ss_height,
	.get_defaults = ss_defaults,
	.get_properties = ss_properties,
	.missing_files = ss_missingfiles,
	.icon_type = OBS_ICON_TYPE_SLIDESHOW,
	.media_play_pause = ss_play_pause,
	.media_restart = ss_restart,
	.media_stop = ss_stop,
	.media_next = ss_next_slide,
	.media_previous = ss_previous_slide,
	.media_get_state = ss_get_state,
	.video_get_color_space = ss_video_get_color_space,
};