/*
 * Copyright 2013 (c) Anna Schumaker.
 */
#include <core/collection.h>
#include <core/idle.h>
#include <core/playlist.h>

#include <glib.h>
#include <stdlib.h>
#include <unistd.h>


static struct file  c_file = FILE_INIT("library.q", 0, 0);
static struct queue c_queue;

struct scan_data {
	struct library *sd_lib;
	gchar *sd_path;
};

static void __scan_dir(void *);


#ifdef CONFIG_TESTING
bool test_collection_error = false;
static inline int __g_access(const gchar *path)
{
	if (test_collection_error)
		return -1;
	return g_access(path, F_OK);
}
#else
#define __g_access(path) g_access(path, F_OK)
#endif /* CONFIG_TESTING */


static void __scan_dir_later(struct library *library, const gchar *dir)
{
	struct scan_data *data = g_malloc(sizeof(struct scan_data));

	data->sd_lib  = library;
	data->sd_path = g_strdup(dir);

	/* data is freed by __scan_dir() */
	idle_schedule(__scan_dir, data);
}

static void __scan_path(struct scan_data *scan, const gchar *name)
{
	gchar *path = g_strdup_printf("%s/%s", scan->sd_path, name);
	struct track *track;

	if (g_file_test(path, G_FILE_TEST_IS_DIR))
		__scan_dir_later(scan->sd_lib, path);
	else {
		track = track_add(scan->sd_lib, path);
		if (track)
			queue_add(&c_queue, track);
	}

	g_free(path);
}

static void __scan_dir(void *data)
{
	struct scan_data *scan = data;
	const char *name;
	GDir *dir;

	dir = g_dir_open(scan->sd_path, 0, NULL);
	if (dir == NULL)
		goto out;

	name = g_dir_read_name(dir);
	while (name != NULL) {
		__scan_path(scan, name);
		name = g_dir_read_name(dir);
	}

	g_dir_close(dir);
	track_db_commit();

out:
	/* Allocated by __scan_dir_later() */
	g_free(scan->sd_path);
	g_free(scan);
}

static void __validate_library(void *data)
{
	struct library *library = data;
	struct db_entry *dbe, *next;
	struct track *track;
	int access;
	gchar *path;

	db_for_each(dbe, next, track_db_get()) {
		track = TRACK(dbe);
		if (track->tr_library != library)
			continue;

		path   = track_path(track);
		access = __g_access(path);
		g_free(path);

		if (access < 0) {
			if (collection_check_library(library) < 0)
				return;
			queue_remove_all(&c_queue, track);
			track_remove(track);
		}
	}
}

void __collection_init_idle(void *data)
{
	struct db_entry *track, *next;
	unsigned int i, n = 0;
	int field, ascending;

	db_for_each(track, next, track_db_get()) {
		if (TRACK(track)->tr_library->li_enabled &&
		    !playlist_has(PL_HIDDEN, TRACK(track)))
			queue_add(&c_queue, TRACK(track));
	}
	queue_unset_flag(&c_queue, Q_ADD_FRONT);

	if (file_open(&c_file, OPEN_READ))
		file_readf(&c_file, "%u %u", &c_queue.q_flags, &n);

	for (i = 0; i < n; i++) {
		file_readf(&c_file, "%u %d", &field, &ascending);
		queue_sort(&c_queue, field + 1, (i == 0) ? true : false);
		if (ascending == false)
			queue_sort(&c_queue, field + 1, false);
	}
	file_close(&c_file);

	if (!c_queue.q_sort) {
		queue_sort(&c_queue, COMPARE_ARTIST, true);
		queue_sort(&c_queue, COMPARE_YEAR,   false);
		queue_sort(&c_queue, COMPARE_TRACK,  false);
	}

	queue_set_flag(&c_queue, Q_SAVE_SORT);
	queue_set_flag(&c_queue, Q_SAVE_FLAGS);

	collection_update_all();
}



/*
 * External API begins here
 */
void collection_init(struct queue_ops *ops)
{
	queue_init(&c_queue, Q_ENABLED | Q_REPEAT | Q_ADD_FRONT, ops);
	idle_schedule(__collection_init_idle, NULL);
}

void collection_deinit()
{
	queue_deinit(&c_queue);
}

void collection_save(struct queue *queue, enum queue_flags flag)
{
	GSList *cur = c_queue.q_sort;
	int field;

	if (&c_queue != queue)
		return;
	if (!file_open(&c_file, OPEN_WRITE))
		return;

	file_writef(&c_file, "%u %u", c_queue.q_flags, g_slist_length(cur));
	while (cur) {
		field = GPOINTER_TO_INT(cur->data);
		file_writef(&c_file, " %u %d", abs(field) - 1, field > 0);
		cur = g_slist_next(cur);
	}
	file_writef(&c_file, "\n");
	file_close(&c_file);
}

struct library *collection_add(const gchar *path)
{
	struct library *library = NULL;

	if (g_file_test(path, G_FILE_TEST_IS_DIR) == false)
		return library;

	library = library_find(path);
	if (library)
		collection_update(library);
	return library;
}

void collection_remove(struct library *library)
{
	if (library) {
		collection_set_enabled(library, false);
		track_remove_all(library);
		library_remove(library);
	}
}

void collection_update(struct library *library)
{
	if (!library)
		return;

	idle_schedule(__validate_library, library);
	__scan_dir_later(library, library->li_path);
}

void collection_update_all()
{
	struct db_entry *library, *next;

	db_for_each(library, next, library_db_get())
		collection_update(LIBRARY(library));
}

bool collection_ban(struct track *track)
{
	bool ret = playlist_add(PL_HIDDEN, track);
	if (ret)
		queue_remove_all(&c_queue, track);
	return ret;
}

bool collection_unban(struct track *track)
{
	bool ret = playlist_remove(PL_HIDDEN, track);
	if (ret)
		queue_add(&c_queue, track);
	return ret;
}

void collection_set_enabled(struct library *library, bool enabled)
{
	struct db_entry *dbe, *next;
	struct track *track;

	if (!library || (library->li_enabled == enabled))
		return;
	if (enabled && (collection_check_library(library) < 0))
		return;

	library_set_enabled(library, enabled);
	queue_set_flag(&c_queue, Q_ADD_FRONT);

	db_for_each(dbe, next, track_db_get()) {
		track = TRACK(dbe);
		if (track->tr_library == library) {
			if (enabled) {
				if (!playlist_has(PL_HIDDEN, track))
					queue_add(&c_queue, track);
			} else
				queue_remove_all(&c_queue, track);
		}
	}

	queue_unset_flag(&c_queue, Q_ADD_FRONT);
	queue_resort(&c_queue);
}

int collection_check_library(struct library *library)
{
	int ret = __g_access(library->li_path);
	if (ret < 0) {
		g_warning("Can't access library at %s/\n", library->li_path);
		collection_set_enabled(library, false);
	}
	return ret;
}

struct queue *collection_get_queue()
{
	return &c_queue;
}