/*
 * Copyright 2014 (c) Anna Schumaker.
 */
#include <core/string.h>
#include <core/tags/track.h>

#include <glib.h>
#include <taglib/tag_c.h>

#define TRACK_DB_MIN 0 /* Ocarina 6.0 */
static struct database track_db;
static unsigned int unplayed_count = 0;
static unsigned int play_count     = 0;

static gchar *__track_key(struct library *library, gchar *path)
{
	gchar *res;

	if (library)
		res = g_strdup_printf("%u/%s", library_index(library), path);
	else
		res = g_strdup("");

	g_free(path);
	return res;
}

static gchar *__track_path(struct track *track)
{
	gchar *path;

	sscanf(track->tr_path, "%*u/%m[^\n]", &path);
	return path;
}

static struct track *__track_alloc()
{
	struct track *track = g_malloc(sizeof(struct track));

	dbe_init(&track->tr_dbe, track);
	return track;
}

static struct track *__track_alloc_filepath(const gchar *filepath)
{
	TagLib_File *file = taglib_file_new(filepath);
	const TagLib_AudioProperties *audio;
	struct track *track = NULL;
	struct artist *artist;
	struct genre *genre;
	TagLib_Tag *tag;

	if (!file || !taglib_file_is_valid(file)) {
		g_printerr("WARNING: Could not read tags for: %s\n", filepath);
		return NULL;
	}

	track  = __track_alloc();
	tag    = taglib_file_tag(file);
	audio  = taglib_file_audioproperties(file);
	artist = artist_find(taglib_tag_artist(tag));
	genre  = genre_find(taglib_tag_genre(tag));

	track->tr_album = album_find(artist, genre, taglib_tag_album(tag),
						    taglib_tag_year(tag));

	track->tr_count  = 0;
	track->tr_length = taglib_audioproperties_length(audio);
	track->tr_track  = taglib_tag_track(tag);
	date_set(&track->tr_date, 0, 0, 0);

	track->tr_title  = g_strdup(taglib_tag_title(tag));
	track->tr_tokens = g_str_tokenize_and_fold(track->tr_title, NULL,
						   &track->tr_alts);

	taglib_tag_free_strings();
	taglib_file_free(file);
	return track;
}

static void __track_free(struct track *track)
{
	g_strfreev(track->tr_tokens);
	g_strfreev(track->tr_alts);
	g_free(track->tr_title);
	g_free(track);
}


struct db_entry *track_alloc(const gchar *key, unsigned int index)
{
	struct library *library;
	char *fullpath, *path;
	struct track *track;
	unsigned int lib_id;

	sscanf(key, "%u/%m[^\n]", &lib_id, &path);
	library  = library_get(lib_id);
	fullpath = library_file(library, path);
	track    = __track_alloc_filepath(fullpath);

	if (track) {
		track->tr_library = library;
		track->tr_path    = g_strdup(key);
		unplayed_count++;
	}

	g_free(path);
	g_free(fullpath);
	return track ? &track->tr_dbe : NULL;
}

static void track_free(struct db_entry *dbe)
{
	struct track *track = TRACK(dbe);

	play_count -= track->tr_count;
	if (track->tr_count == 0)
		unplayed_count--;

	__track_free(track);
}

static gchar *track_key(struct db_entry *dbe)
{
	return TRACK(dbe)->tr_path;
}

static void track_read_v0(struct file *file, struct track *track)
{
	struct artist *artist = artist_get(file_readu(file));
	struct album  *album  = album_get( file_readu(file));
	struct genre  *genre  = genre_get( file_readu(file));

	track->tr_track = file_readhu(file);
	date_read(file, &track->tr_date);

	if (album->al_artist != artist || album->al_genre != genre)
		album = album_find(artist, genre, album->al_name, album->al_year);

	track->tr_album = album;
}

static struct db_entry *track_read(struct file *file, unsigned int index)
{
	struct track *track = __track_alloc();

	track->tr_library = library_get(file_readu(file));

	if (file_version(file) == 0)
		track_read_v0(file, track);
	else {
		track->tr_album = album_get(file_readu(file));
		track->tr_track = file_readhu(file);
		date_read_stamp(file, &track->tr_date);
	}

	track->tr_count  = file_readhu(file);
	track->tr_length = file_readhu(file);

	play_count += track->tr_count;
	if (track->tr_count == 0)
		unplayed_count++;

	track->tr_title  = file_readl(file);
	track->tr_tokens = g_str_tokenize_and_fold(track->tr_title, NULL,
						   &track->tr_alts);
	track->tr_path  = __track_key(track->tr_library, file_readl(file));
	return &track->tr_dbe;

}

static void track_write(struct file *file, struct db_entry *dbe)
{
	struct track *track = TRACK(dbe);
	gchar *path = __track_path(track);

	file_writef(file, "%u %u %hu ", library_index(track->tr_library),
					album_index(track->tr_album),
					track->tr_track);
	date_write_stamp(file, &track->tr_date);
	file_writef(file, " %hu %hu %s\n%s", track->tr_count,
					     track->tr_length,
					     track->tr_title,
					     path);

	g_free(path);
}


static const struct db_ops track_ops = {
	.dbe_alloc = track_alloc,
	.dbe_free  = track_free,
	.dbe_key   = track_key,
	.dbe_read  = track_read,
	.dbe_write = track_write,
};


void track_db_init()
{
	db_init(&track_db, "track.db", false, &track_ops, TRACK_DB_MIN);
	db_load(&track_db);
}

void track_db_deinit()
{
	db_deinit(&track_db);
}

void track_db_commit()
{
	db_save(&track_db);
}

bool track_db_defrag()
{
	return db_defrag(&track_db);
}

void track_db_rekey()
{
	struct db_entry *dbe, *next;
	struct track *track;
	unsigned int lib;
	gchar *path;

	db_for_each(dbe, next, &track_db) {
		track = TRACK(dbe);

		sscanf(track->tr_path, "%u/%m[^\n]", &lib, &path);
		if (lib != library_index(track->tr_library)) {
			track->tr_path = __track_key(track->tr_library, path);
			db_rekey(&track_db, dbe);
		} else
			g_free(path);
	}
}

const struct database *track_db_get()
{
	return &track_db;
}

unsigned int track_db_count_unplayed()
{
	return unplayed_count;
}

unsigned int track_db_count_plays()
{
	return play_count;
}

unsigned int track_db_average_plays()
{
	if (unplayed_count == track_db.db_size)
		return 0;
	return play_count / (track_db.db_size - unplayed_count);
}

struct track *track_alloc_external(const gchar *filepath)
{
	struct track *track = __track_alloc_filepath(filepath);
	if (track) {
		track->tr_library = NULL;
		track->tr_path    = g_strdup(filepath);
	}
	return track;
}

void track_free_external(struct track *track)
{
	if (TRACK_IS_EXTERNAL(track)) {
		g_free(track->tr_path);
		__track_free(track);
	}
}

struct track *track_add(struct library *library, const gchar *filepath)
{
	unsigned int offset = strlen(library->li_path) + 1;
	gchar *key = __track_key(library, g_strdup(filepath + offset));
	struct track *track = NULL;

	if (!db_get(&track_db, key))
		track = TRACK(db_insert(&track_db, key));

	g_free(key);
	return track;
}

void track_remove(struct track *track)
{
	db_remove(&track_db, &track->tr_dbe);
}

void track_remove_all(struct library *library)
{
	struct db_entry *it, *next;

	db_for_each(it, next, &track_db) {
		if (TRACK(it)->tr_library == library)
			db_remove(&track_db, it);
	}
	track_db_commit();
}

struct track *track_get(const unsigned int index)
{
	return TRACK(db_at(&track_db, index));
}

struct track *track_lookup(const gchar *filepath)
{
	struct library *library = library_lookup(filepath);
	unsigned int offset;
	struct track *track;
	gchar *key;

	if (!library)
		return NULL;

	offset = strlen(library->li_path) + 1;
	key    = __track_key(library, g_strdup(filepath + offset));
	track  = TRACK(db_get(&track_db, key));
	g_free(key);
	return track;
}

int track_compare(struct track *lhs, struct track *rhs, enum compare_t compare)
{
	switch (compare) {
	case COMPARE_ARTIST:
		return artist_compare(lhs->tr_album->al_artist,
				      rhs->tr_album->al_artist);
	case COMPARE_ALBUM:
		return album_compare(lhs->tr_album, rhs->tr_album);
	case COMPARE_COUNT:
		return lhs->tr_count - rhs->tr_count;
	case COMPARE_GENRE:
		return genre_compare(lhs->tr_album->al_genre,
				     rhs->tr_album->al_genre);
	case COMPARE_LENGTH:
		return lhs->tr_length - rhs->tr_length;
	case COMPARE_PLAYED:
		return date_compare(&lhs->tr_date, &rhs->tr_date);
	case COMPARE_TITLE:
		return string_compare_tokens(lhs->tr_tokens, rhs->tr_tokens);
	case COMPARE_TRACK:
		return lhs->tr_track - rhs->tr_track;
	case COMPARE_YEAR:
		return album_compare_year(lhs->tr_album, rhs->tr_album);
	}

	return 0; /* We should never get here. */
}

bool track_match_token(struct track *track, const gchar *token)
{
	return  string_match_token(token, track->tr_tokens) ||
		string_match_token(token, track->tr_alts);
}

gchar *track_path(struct track *track)
{
	gchar *path, *res;

	if (track->tr_library) {
		path = __track_path(track);
		res  = library_file(track->tr_library, path);
		g_free(path);
		return res;
	}
	return g_strdup(track->tr_path);
}

void track_played(struct track *track)
{
	if (TRACK_IS_EXTERNAL(track))
		return;
	if (track->tr_count == 0)
		unplayed_count--;
	track->tr_count++;
	play_count++;
	date_today(&track->tr_date);
	track_db_commit();
}

gchar *track_last_play(struct track *track)
{
	if (track->tr_count > 0)
		return date_string(&track->tr_date);
	return g_strdup("Never");
}

#ifdef CONFIG_TESTING
const struct db_ops *test_track_ops() { return &track_ops; }
#endif /* CONFIG_TESTING */