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

static struct file  sys_file = FILE_INIT("playlist.db", 0, 0);
static struct queue sys_playlists[SYS_PL_NUM_PLAYLISTS];
static bool __sys_pl_remove(enum sys_playlist_t, struct track *);

static enum sys_playlist_t __sys_pl_convert(const gchar *name)
{
	if (string_match(name, "Favorites"))
		return SYS_PL_FAVORITES;
	else if (string_match(name, "Hidden") || string_match(name, "Banned"))
		return SYS_PL_HIDDEN;
	else if (string_match(name, "Unplayed"))
		return SYS_PL_UNPLAYED;
	return SYS_PL_NUM_PLAYLISTS;
}

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_playlists[SYS_PL_FAVORITES], &sys_file);
	file_writef(&sys_file, "\n1 %s\n", "Banned");
	queue_save_tracks(&sys_playlists[SYS_PL_HIDDEN], &sys_file);
	file_writef(&sys_file, "\n");

	file_close(&sys_file);
}

static bool __sys_pl_load()
{
	enum sys_playlist_t plist;
	unsigned int i, n;
	gchar *name;

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

	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_convert(name);
		queue_load_tracks(&sys_playlists[plist], &sys_file);
		g_free(name);
	}

	file_close(&sys_file);
	return true;
}

static bool __sys_pl_can_add(enum sys_playlist_t plist, struct track *track)
{
	if (track->tr_count == 0)
		return plist == SYS_PL_UNPLAYED;
	return false;
}

static bool __sys_pl_add(enum sys_playlist_t plist, struct track *track)
{
	if (plist != SYS_PL_FAVORITES && plist != SYS_PL_HIDDEN) {
		if (!__sys_pl_can_add(plist, track))
			return false;
		if (queue_has(&sys_playlists[SYS_PL_HIDDEN], track))
			return false;
	}

	if (queue_has(&sys_playlists[plist], track))
		return false;
	queue_add(&sys_playlists[plist], track);

	switch (plist) {
	case SYS_PL_HIDDEN:
		__sys_pl_remove(SYS_PL_UNPLAYED, track);
	case SYS_PL_FAVORITES:
		__sys_pl_save();
	default:
		break;
	}
	return true;
}

static bool __sys_pl_remove(enum sys_playlist_t plist, struct track *track)
{
	if (!queue_remove_all(&sys_playlists[plist], track))
		return false;

	switch (plist) {
	case SYS_PL_HIDDEN:
		__sys_pl_add(SYS_PL_UNPLAYED, track);
	case SYS_PL_FAVORITES:
		__sys_pl_save();
	default:
		break;
	}
	return true;
}

static bool __sys_pl_update(enum sys_playlist_t plist)
{
	struct db_entry *dbe, *next;

	db_for_each(dbe, next, track_db_get()) {
		if (TRACK(dbe)->tr_count == 0)
			__sys_pl_add(SYS_PL_UNPLAYED, TRACK(dbe));
		else
			__sys_pl_remove(SYS_PL_UNPLAYED, TRACK(dbe));
	}

	queue_unset_flag(&sys_playlists[plist], Q_ADD_FRONT);
	return true;
}


static struct queue *pl_system_get_queue(const gchar *name)
{
	enum sys_playlist_t plist = __sys_pl_convert(name);
	if (plist == SYS_PL_NUM_PLAYLISTS)
		return NULL;
	return &sys_playlists[plist];
}

static bool pl_system_add_track(const gchar *name, struct track *track)
{
	enum sys_playlist_t plist = __sys_pl_convert(name);
	if (plist == SYS_PL_NUM_PLAYLISTS)
		return false;
	return __sys_pl_add(plist, track);
}

static bool pl_system_remove_track(const gchar *name, struct track *track)
{
	enum sys_playlist_t plist = __sys_pl_convert(name);
	if (plist == SYS_PL_NUM_PLAYLISTS)
		return false;
	return __sys_pl_remove(plist, track);
}

static void pl_system_update(const gchar *name)
{
	enum sys_playlist_t plist = __sys_pl_convert(name);
	if (plist != SYS_PL_FAVORITES && plist != SYS_PL_HIDDEN)
		idle_schedule(IDLE_SYNC, IDLE_FUNC(__sys_pl_update),
					 GUINT_TO_POINTER(plist));
}


struct playlist_type pl_system = {
	.pl_get_queue    = pl_system_get_queue,
	.pl_add_track    = pl_system_add_track,
	.pl_remove_track = pl_system_remove_track,
	.pl_update       = pl_system_update,
};


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

	for (i = 0; i < SYS_PL_NUM_PLAYLISTS; i++) {
		queue_init(&sys_playlists[i], Q_ENABLED | Q_REPEAT, ops);
		queue_sort(&sys_playlists[i], COMPARE_ARTIST, true);
		queue_sort(&sys_playlists[i], COMPARE_YEAR,   false);
		queue_sort(&sys_playlists[i], COMPARE_TRACK,  false);
		if (i >= SYS_PL_UNPLAYED)
			queue_set_flag(&sys_playlists[i], Q_ADD_FRONT);
	}

	idle_schedule(IDLE_SYNC, __sys_pl_load,   NULL);
	pl_system_update("Unplayed");
}

void pl_system_deinit()
{
	unsigned int i;

	for (i = 0; i < SYS_PL_NUM_PLAYLISTS; i++)
		queue_deinit(&sys_playlists[i]);
}