extends GdUnitTestSuite
## Downloaded songs are kept in files in the songs folder, not in memory.

var _snapshot: AutoloadSnapshot
var _config_dir_before: String
var _mp3: PackedByteArray


func before_test() -> void:
	_snapshot = AutoloadSnapshot.take([Playlist])
	_config_dir_before = OS.get_environment(Settings.CONFIG_DIR_ENV)
	OS.set_environment(Settings.CONFIG_DIR_ENV, create_temp_dir("song_files"))
	Playlist.clear_song_files()
	Playlist.song_object_array.clear()
	_mp3 = FileAccess.get_file_as_bytes("res://tests/data/short.mp3")


func after_test() -> void:
	Playlist.clear_song_files()
	OS.set_environment(Settings.CONFIG_DIR_ENV, _config_dir_before)
	_snapshot.restore()


func _add_song() -> SongObject:
	var song_object: SongObject = SongObject.new()
	Playlist.store_song(song_object, _mp3)
	Playlist.add_to_playlist(song_object)
	return song_object


func test_stored_song_is_a_file_and_plays_back() -> void:
	var song_object: SongObject = _add_song()

	assert_object(song_object.song).is_null()
	assert_bool(FileAccess.file_exists(song_object.song_path)).is_true()
	var stream: AudioStream = Playlist.get_song(0)
	assert_object(stream).is_instanceof(AudioStreamMP3)
	assert_float(stream.get_length()).is_greater(0.0)


func test_every_song_gets_a_file_of_its_own() -> void:
	var first: SongObject = _add_song()
	var second: SongObject = _add_song()

	assert_str(first.song_path).is_not_equal(second.song_path)
	assert_array(DirAccess.get_files_at(Playlist.songs_folder())).has_size(2)


func test_downloading_a_song_again_replaces_its_file() -> void:
	var song_object: SongObject = _add_song()
	var old_path: String = song_object.song_path

	Playlist.add_song_to_song_object(0, _mp3)

	assert_str(song_object.song_path).is_not_equal(old_path)
	assert_object(Playlist.get_song(0)).is_not_null()


func test_resetting_the_playlist_deletes_the_files() -> void:
	_add_song()
	_add_song()

	Playlist.reset_playlist()

	assert_array(DirAccess.get_files_at(Playlist.songs_folder())).is_empty()


func test_missing_file_gives_no_song_so_it_is_downloaded_again() -> void:
	var song_object: SongObject = _add_song()

	DirAccess.remove_absolute(song_object.song_path)

	assert_object(Playlist.get_song(0)).is_null()


func test_song_stays_in_memory_when_it_cannot_be_saved() -> void:
	# A file where the folder should be, so the folder can't be made
	var blocker: String = create_temp_dir("song_files_blocked").path_join("not_a_folder")
	FileAccess.open(blocker, FileAccess.WRITE).store_string("x")
	OS.set_environment(Settings.CONFIG_DIR_ENV, blocker)

	var song_object: SongObject = _add_song()

	assert_str(song_object.song_path).is_empty()
	assert_object(Playlist.get_song(0)).is_instanceof(AudioStreamMP3)


func test_new_songs_never_write_over_files_kept_from_a_saved_quiz() -> void:
	var kept: SongObject = _add_song()
	var kept_bytes: PackedByteArray = FileAccess.get_file_as_bytes(kept.song_path)
	# As after a restart: the count of files written starts over
	Playlist._song_files_written = 0

	var new_song: SongObject = _add_song()

	assert_str(new_song.song_path).is_not_equal(kept.song_path)
	assert_array(FileAccess.get_file_as_bytes(kept.song_path)).is_equal(kept_bytes)
	assert_array(DirAccess.get_files_at(Playlist.songs_folder())).has_size(2)


func test_clearing_can_keep_the_files_a_saved_quiz_uses() -> void:
	var kept: SongObject = _add_song()
	var dropped: SongObject = _add_song()

	Playlist.clear_song_files(PackedStringArray([kept.song_path]))

	assert_bool(FileAccess.file_exists(kept.song_path)).is_true()
	assert_bool(FileAccess.file_exists(dropped.song_path)).is_false()