/*
 * Copyright 2016 (c) Anna Schumaker.
 */
#include <core/idle.h>
#include <core/playlists/system.h>
#include <core/string.h>

static bool pl_system_add_track(const gchar *, struct track *);
static bool pl_system_remove_track(const gchar *, struct track *);
static inline struct queue *__sys_pl_queue(enum sys_playlist_t);
static void __sys_pl_save();

static struct file sys_file         = FILE_INIT("playlist.db", 0, 0);
static struct file sys_collection_f = FILE_INIT("library.q",   0, 0);
static struct sys_playlist *sys_playlists[SYS_PL_NUM_PLAYLISTS];


/*
 * Generic system playlist operations.
 */
static void sys_pl_generic_init(struct playlist *playlist, unsigned int flags,
				struct queue_ops *ops)
{
	playlist_generic_init(playlist, Q_REPEAT | Q_ADD_FRONT, ops);
}

static bool sys_pl_generic_add(struct playlist *playlist, struct track *track)
{
	if (queue_has(__sys_pl_queue(SYS_PL_HIDDEN), track))
		return false;
	return playlist_generic_add_track(playlist, track);
}


/*
 * Favorite tracks playlist operations.
 */
static bool sys_pl_favorites_add(struct playlist *playlist, struct track *track)
{
	bool ret = playlist_generic_add_track(playlist, track);
	__sys_pl_save();
	return ret;
}

static bool sys_pl_favorites_remove(struct playlist *playlist, struct track *track)
{
	bool ret = playlist_generic_remove_track(playlist, track);
	__sys_pl_save();
	return ret;
}

static struct sys_playlist sys_favorites = {
	.spl_playlist = DEFINE_PLAYLIST(PL_SYSTEM, "Favorites"),
	.spl_init     = playlist_generic_init,
	.spl_add      = sys_pl_favorites_add,
	.spl_remove   = sys_pl_favorites_remove,
	.spl_set_flag = playlist_generic_set_flag,
	.spl_sort     = playlist_generic_sort,
};


/*
 * Hidden tracks playlist operations.
 */
static bool sys_pl_hidden_add(struct playlist *playlist, struct track *track)
{
	bool ret = playlist_generic_add_track(playlist, track);
	pl_system_remove_track("Collection",   track);
	pl_system_remove_track("Unplayed",     track);
	pl_system_remove_track("Most Played",  track);
	pl_system_remove_track("Least Played", track);
	__sys_pl_save();
	return ret;
}

static bool sys_pl_hidden_remove(struct playlist *playlist, struct track *track)
{
	bool ret = playlist_generic_remove_track(playlist, track);
	pl_system_add_track("Collection",   track);
	pl_system_add_track("Unplayed",     track);
	pl_system_add_track("Most Played",  track);
	pl_system_add_track("Least Played", track);
	__sys_pl_save();
	return ret;
}

static struct sys_playlist sys_hidden = {
	.spl_playlist = DEFINE_PLAYLIST(PL_SYSTEM, "Hidden"),
	.spl_init     = playlist_generic_init,
	.spl_add      = sys_pl_hidden_add,
	.spl_remove   = sys_pl_hidden_remove,
	.spl_set_flag = playlist_generic_set_flag,
	.spl_sort     = playlist_generic_sort,
};


/*
 * Collection playlist operations.
 */
static void sys_pl_collection_save(struct playlist *playlist)
{
	if (file_open(&sys_collection_f, OPEN_WRITE)) {
		queue_save_flags(&playlist->pl_queue, &sys_collection_f);
		file_close(&sys_collection_f);
	}
}

static void sys_pl_collection_load(struct playlist *playlist)
{
	if (file_open(&sys_collection_f, OPEN_READ)) {
		queue_load_flags(&playlist->pl_queue, &sys_collection_f);
		queue_unset_flag(&playlist->pl_queue, Q_SAVE_FLAGS);
		queue_unset_flag(&playlist->pl_queue, Q_SAVE_SORT);
		file_close(&sys_collection_f);
	}
}

static bool sys_pl_collection_add(struct playlist *playlist, struct track *track)
{
	if (track->tr_library->li_enabled != true)
		return false;
	return sys_pl_generic_add(playlist, track);
}

static bool sys_pl_collection_update(struct playlist *playlist,
				     struct track *track)
{
	if (track->tr_library->li_enabled != true)
		return false;
	return sys_pl_generic_add(playlist, track) || true;
}

static void sys_pl_collection_set_flag(struct playlist *playlist,
				       enum queue_flags flag, bool enabled)
{
	playlist_generic_set_flag(playlist, flag, enabled);
	sys_pl_collection_save(playlist);
}

static void sys_pl_collection_sort(struct playlist *playlist,
				   enum compare_t sort, bool reset)
{
	playlist_generic_sort(playlist, sort, reset);
	sys_pl_collection_save(playlist);
}

static struct sys_playlist sys_collection = {
	.spl_playlist = DEFINE_PLAYLIST(PL_SYSTEM, "Collection"),
	.spl_init     = sys_pl_generic_init,
	.spl_add      = sys_pl_collection_add,
	.spl_remove   = playlist_generic_remove_track,
	.spl_update   = sys_pl_collection_update,
	.spl_set_flag = sys_pl_collection_set_flag,
	.spl_sort     = sys_pl_collection_sort,
};


/*
 * History playlist operations.
 */
static void sys_pl_history_init(struct playlist *playlist,
				 unsigned int flags, struct queue_ops *ops)
{
	queue_init(&playlist->pl_queue,
		   Q_ENABLED | Q_REPEAT | Q_ADD_FRONT | Q_NO_SORT,
		   ops, playlist);
}

static bool sys_pl_history_add(struct playlist *playlist, struct track *track)
{
	queue_add(&playlist->pl_queue, track);
	queue_iter_set(&playlist->pl_queue, &playlist->pl_queue.q_cur, 0);
	return true;
}

static struct sys_playlist sys_history = {
	.spl_playlist = DEFINE_PLAYLIST(PL_SYSTEM, "History"),
	.spl_init     = sys_pl_history_init,
	.spl_add      = sys_pl_history_add,
	.spl_remove   = playlist_generic_remove_track,
	.spl_set_flag = playlist_noop_set_flag,
	.spl_sort     = playlist_noop_sort,
};


/*
 * Unplayed tracks playlist operations.
 */
static bool sys_pl_unplayed_add(struct playlist *playlist, struct track *track)
{
	if (track->tr_count > 0)
		return false;
	return sys_pl_generic_add(playlist, track);
}

static bool sys_pl_unplayed_update(struct playlist *playlist,
				   struct track *track)
{
	if (track->tr_count > 0)
		return false;
	return sys_pl_generic_add(playlist, track) || true;
}

static struct sys_playlist sys_unplayed = {
	.spl_playlist = DEFINE_PLAYLIST(PL_SYSTEM, "Unplayed"),
	.spl_init     = sys_pl_generic_init,
	.spl_add      = sys_pl_unplayed_add,
	.spl_remove   = playlist_generic_remove_track,
	.spl_update   = sys_pl_unplayed_update,
	.spl_set_flag = playlist_generic_set_flag,
	.spl_sort     = playlist_generic_sort,
};


/*
 * Most played tracks playlist operations.
 */
static bool sys_pl_most_played_add(struct playlist *playlist, struct track *track)
{
	unsigned int average = track_db_average_plays();
	if (track->tr_count <= average)
		return false;
	return sys_pl_generic_add(playlist, track);
}

static bool sys_pl_most_played_update(struct playlist *playlist,
				      struct track *track)
{
	unsigned int average = track_db_average_plays();
	if (track->tr_count <= average)
		return false;
	return sys_pl_generic_add(playlist, track) || true;
}

static struct sys_playlist sys_most_played = {
	.spl_playlist = DEFINE_PLAYLIST(PL_SYSTEM, "Most Played"),
	.spl_init     = sys_pl_generic_init,
	.spl_add      = sys_pl_most_played_add,
	.spl_remove   = playlist_generic_remove_track,
	.spl_update   = sys_pl_most_played_update,
	.spl_set_flag = playlist_generic_set_flag,
	.spl_sort     = playlist_generic_sort,
};


/*
 * Least played tracks playlist operations.
 */
static bool sys_pl_least_played_add(struct playlist *playlist, struct track *track)
{
	unsigned int average = track_db_average_plays();
	if (!track->tr_count || track->tr_count > average)
		return false;
	return sys_pl_generic_add(playlist, track);
}

static bool sys_pl_least_played_update(struct playlist *playlist,
				       struct track *track)
{
	unsigned int average = track_db_average_plays();
	if (!track->tr_count || track->tr_count > average)
		return false;
	return sys_pl_generic_add(playlist, track) || true;
}

static struct sys_playlist sys_least_played = {
	.spl_playlist = DEFINE_PLAYLIST(PL_SYSTEM, "Least Played"),
	.spl_init     = sys_pl_generic_init,
	.spl_add      = sys_pl_least_played_add,
	.spl_remove   = playlist_generic_remove_track,
	.spl_update   = sys_pl_least_played_update,
	.spl_set_flag = playlist_generic_set_flag,
	.spl_sort     = playlist_generic_sort,
};


static struct sys_playlist *sys_playlists[SYS_PL_NUM_PLAYLISTS] = {
	[SYS_PL_FAVORITES]    = &sys_favorites,
	[SYS_PL_HIDDEN]       = &sys_hidden,
	[SYS_PL_COLLECTION]   = &sys_collection,
	[SYS_PL_HISTORY]      = &sys_history,
	[SYS_PL_UNPLAYED]     = &sys_unplayed,
	[SYS_PL_MOST_PLAYED]  = &sys_most_played,
	[SYS_PL_LEAST_PLAYED] = &sys_least_played,
};


static struct sys_playlist * __sys_pl_lookup(const gchar *name)
{
	if (string_match(name, "Favorites"))
		return &sys_favorites;
	else if (string_match(name, "Hidden") || string_match(name, "Banned"))
		return &sys_hidden;
	else if (string_match(name, "Collection"))
		return &sys_collection;
	else if (string_match(name, "History"))
		return &sys_history;
	else if (string_match(name, "Unplayed"))
		return &sys_unplayed;
	else if (string_match(name, "Most Played"))
		return &sys_most_played;
	else if (string_match(name, "Least Played"))
		return &sys_least_played;
	return NULL;
}

static inline struct queue *__sys_pl_queue(enum sys_playlist_t plist)
{
	return &sys_playlists[plist]->spl_playlist.pl_queue;
}

static void __sys_pl_save()
{
	if (!file_open(&sys_file, OPEN_WRITE))
		return;

	file_writef(&sys_file, "%u\n 1 %s\n", 2, "Favorites");
	queue_save_tracks(__sys_pl_queue(SYS_PL_FAVORITES), &sys_file);
	file_writef(&sys_file, "\n1 %s\n", "Banned");
	queue_save_tracks(__sys_pl_queue(SYS_PL_HIDDEN), &sys_file);
	file_writef(&sys_file, "\n");

	file_close(&sys_file);
}

static void __sys_pl_load_playlists()
{
	struct sys_playlist *plist;
	unsigned int i, n;
	gchar *name;

	if (!file_open(&sys_file, OPEN_READ))
		return;

	file_readf(&sys_file, "%u\n", &n);
	for (i = 0; i < n; i++) {
		file_readf(&sys_file, "%*u %m[^\n]\n", &name);

		plist = __sys_pl_lookup(name);
		if (plist)
			queue_load_tracks(&plist->spl_playlist.pl_queue, &sys_file);
		g_free(name);
	}

	file_close(&sys_file);
	return;
}

static bool __sys_pl_load()
{
	__sys_pl_load_playlists();
	sys_pl_collection_load(&__sys_pl_lookup("Collection")->spl_playlist);
	return true;
}


static struct queue *pl_system_get_queue(const gchar *name)
{
	struct sys_playlist *sys_pl = __sys_pl_lookup(name);
	return sys_pl ? &sys_pl->spl_playlist.pl_queue : NULL;
}

static bool pl_system_new_delete(const gchar *name)
{
	return false;
}

static bool pl_system_add_track(const gchar *name, struct track *track)
{
	struct sys_playlist *sys_pl = __sys_pl_lookup(name);
	return sys_pl ? sys_pl->spl_add(&sys_pl->spl_playlist, track) : false;
}

static bool pl_system_remove_track(const gchar *name, struct track *track)
{
	struct sys_playlist *sys_pl = __sys_pl_lookup(name);
	return sys_pl ? sys_pl->spl_remove(&sys_pl->spl_playlist, track) : false;
}

static void pl_system_update(const gchar *name)
{
	struct sys_playlist *sys_pl = __sys_pl_lookup(name);
	if (sys_pl)
		playlist_generic_update(&sys_pl->spl_playlist, sys_pl->spl_update);
}

static void pl_system_set_flag(const gchar *name, enum queue_flags flag,
			       bool enabled)
{
	struct sys_playlist *sys_pl = __sys_pl_lookup(name);
	if (sys_pl)
		sys_pl->spl_set_flag(&sys_pl->spl_playlist, flag, enabled);
}

static void pl_system_sort(const gchar *name, enum compare_t sort, bool reset)
{
	struct sys_playlist *sys_pl = __sys_pl_lookup(name);
	if (sys_pl)
		sys_pl->spl_sort(&sys_pl->spl_playlist, sort, reset);
}


struct playlist_type pl_system = {
	.pl_get_queue    = pl_system_get_queue,
	.pl_new          = pl_system_new_delete,
	.pl_delete       = pl_system_new_delete,
	.pl_add_track    = pl_system_add_track,
	.pl_remove_track = pl_system_remove_track,
	.pl_update       = pl_system_update,
	.pl_set_flag     = pl_system_set_flag,
	.pl_sort         = pl_system_sort,
};


void pl_system_init(struct queue_ops *ops)
{
	struct sys_playlist *sys_pl;
	unsigned int i;

	for (i = 0; i < SYS_PL_NUM_PLAYLISTS; i++) {
		sys_pl = sys_playlists[i];
		sys_pl->spl_init(&sys_pl->spl_playlist, 0, ops);
	}

	idle_schedule(IDLE_SYNC, __sys_pl_load,   NULL);
	pl_system_update("Collection");
	pl_system_update("Unplayed");
	pl_system_update("Most Played");
	pl_system_update("Least Played");
}

void pl_system_deinit()
{
	unsigned int i;

	for (i = 0; i < SYS_PL_NUM_PLAYLISTS; i++)
		queue_deinit(__sys_pl_queue(i));
}

void pl_system_new_track(struct track *track)
{
	pl_system_add_track("Collection", track);
	pl_system_add_track("Unplayed",   track);
}

void pl_system_delete_track(struct track *track)
{
	struct sys_playlist *sys_pl;
	unsigned int i;

	for (i = 0; i < SYS_PL_NUM_PLAYLISTS; i++) {
		sys_pl = sys_playlists[i];
		sys_pl->spl_remove(&sys_pl->spl_playlist, track);
	}
}