class_name SettingsPopup
extends BasePopup
## The application settings: which MusicServer or music folder to play from, the theme,
## fullscreen, fewer animations, how many songs to download ahead, how random songs are
## picked and whether plays count in the statistics, and a button that opens the folder
## the settings are kept in. Opened from the Settings button in the top bar.
##
## A music folder (see [MusicFolder]) is used instead of the server until Use server is
## pressed or the game is closed. The settings that need the server are off meanwhile.
## A folder of characters (see [FolderCharacters]) is used the same way; without one, a
## music folder's own [code]characters[/code] folder is used, or else the server's.
##
## The quiz settings, such as the winning score, are in [QuizSettingsCard].

## Emitted when another MusicServer or music folder is picked, or a prepared quiz's play
## order is changed. A new game starts.
signal server_changed

## Emitted when a folder of characters is picked or Use server is pressed for them.
signal characters_changed
## Emitted when Clear cache is pressed, for the caches to delete their files.
signal clear_cache_requested

## Space between the rows and the panel's edges.
const PADDING: Vector2 = Vector2(20, 12)

@onready var settings_panel: Panel = %SettingsPanel
@onready var select_server_button: OptionButton = %SelectServerButton
@onready var fullscreen_button: CheckButton = %FullscreenButton
@onready var reduce_animations_button: CheckButton = %ReduceAnimationsButton
@onready var theme_button: OptionButton = %ThemeButton
@onready var cache_label: Label = %CacheLabel
@onready var lower_cache_button: Button = %LowerCacheButton
@onready var increase_cache_button: Button = %IncreaseCacheButton
@onready var random_mode_button: OptionButton = %RandomModeButton
@onready var add_to_database_button: CheckButton = %AddToDatabaseCheckButton
@onready var rows: VBoxContainer = %VBoxContainer
@onready var folder_label: Label = %FolderLabel
@onready var choose_folder_button: Button = %ChooseFolderButton
@onready var use_server_button: Button = %UseServerButton
@onready var folder_error_label: Label = %FolderErrorLabel
@onready var play_order_row: HBoxContainer = %PlayOrderRow
@onready var play_order_button: OptionButton = %PlayOrderButton
@onready var folder_dialog: FileDialog = %FolderDialog
@onready var characters_label: Label = %CharactersLabel
@onready var choose_characters_button: Button = %ChooseCharactersButton
@onready var use_server_characters_button: Button = %UseServerCharactersButton
@onready var characters_error_label: Label = %CharactersErrorLabel
@onready var character_folder_dialog: FileDialog = %CharacterFolderDialog
@onready var open_config_folder_button: Button = %OpenConfigFolderButton
@onready var cache_size_label: Label = %CacheSizeLabel
@onready var clear_cache_button: Button = %ClearCacheButton

## Shows a folder in the system's file manager. The tests replace it, so no file manager
## opens while they run.
var show_folder: Callable = _show_in_file_manager

# Where the panel's middle is, so it stays centred when rows are shown or hidden
var _panel_middle_y: float = 0.0


func _ready() -> void:
	for server: String in Settings.servers:
		select_server_button.add_item(server)
	for entry: Dictionary in Settings.THEMES:
		theme_button.add_item(entry.name)
	theme_button.select(Settings.THEMES.find(Settings.theme_entry(Settings.theme_id)))
	theme_button.item_selected.connect(select_theme)
	fullscreen_button.button_pressed = Settings.fullscreen
	select_server_button.select(Settings.selected_server)
	cache_label.text = str(Playlist.number_of_tracks_to_preload)

	fullscreen_button.pressed.connect(fullscreen)
	reduce_animations_button.button_pressed = Settings.reduce_animations
	reduce_animations_button.toggled.connect(set_reduce_animations)
	choose_folder_button.pressed.connect(folder_dialog.popup_centered)
	folder_dialog.dir_selected.connect(use_music_folder)
	use_server_button.pressed.connect(use_server)
	choose_characters_button.pressed.connect(character_folder_dialog.popup_centered)
	character_folder_dialog.dir_selected.connect(use_character_folder)
	use_server_characters_button.pressed.connect(use_server_characters)
	open_config_folder_button.pressed.connect(open_config_folder)
	open_config_folder_button.tooltip_text = Settings.config_dir()
	clear_cache_button.pressed.connect(clear_cache)
	play_order_button.item_selected.connect(_on_play_order_selected)
	lower_cache_button.pressed.connect(lower_cache)
	increase_cache_button.pressed.connect(increase_cache)
	select_server_button.item_selected.connect(select_server)
	random_mode_button.item_selected.connect(
			func(mode: int) -> void: Settings.random_mode = mode as Settings.RandomMode)
	add_to_database_button.toggled.connect(func(on: bool) -> void: Settings.add_to_stats = on)
	visibility_changed.connect(_on_visibility_changed)
	# Alt+Enter switches fullscreen from the main window, which resizes the window
	get_window().size_changed.connect(_update_fullscreen_button)
	_panel_middle_y = settings_panel.position.y + settings_panel.size.y / 2
	_show_music_source()


## Switches to the theme at [param index] in [constant Settings.THEMES] at once.
func select_theme(index: int) -> void:
	Settings.apply_theme(Settings.THEMES[index].id)


## Turns every animation off or on, and saves it.
func set_reduce_animations(on: bool) -> void:
	Settings.reduce_animations = on
	Settings.save_settings()


func fullscreen() -> void:
	Settings.set_fullscreen(!Settings.fullscreen)


## Plays songs from the folder at [param path] instead of the server's. A folder with
## nothing to play is not used, and the popup says so.
func use_music_folder(path: String) -> void:
	var folder: MusicFolder = MusicFolder.scan(path)
	if folder.kind == MusicFolder.Kind.EMPTY:
		folder_error_label.text = "No songs found in " + folder.display_name()
		folder_error_label.visible = true
		_fit_to_rows()
		return
	folder.set_play_order(play_order_button.selected as MusicFolder.PlayOrder)
	Settings.music_folder = folder
	_show_music_source()
	server_changed.emit()


## Plays from the server again instead of the music folder.
func use_server() -> void:
	Settings.music_folder = null
	_show_music_source()
	server_changed.emit()


## Shows the folder with the config file, the saved settings and the cached characters
## and songs in the system's file manager.
func open_config_folder() -> void:
	var dir: String = Settings.config_dir()
	DirAccess.make_dir_recursive_absolute(dir)
	show_folder.call(dir)


## Deletes the downloaded character pictures, covers and songs, except the songs the
## quiz uses, and shows how much space that freed.
func clear_cache() -> void:
	var freed: int = cache_size()
	clear_cache_requested.emit()
	Playlist.clear_song_files(Playlist.song_files_in_use())
	cache_size_label.text = "Cleared " + size_text(freed)
	clear_cache_button.disabled = true


## Shows how much space the downloaded files take.
func show_cache_size() -> void:
	var size: int = cache_size()
	cache_size_label.text = size_text(size)
	clear_cache_button.disabled = size == 0


## How many bytes the downloaded character pictures, covers and songs take, leaving out
## the songs the quiz uses, which clearing keeps.
static func cache_size() -> int:
	return FileCache.folder_size(CharacterCache.folder()) \
			+ FileCache.folder_size(CoverCache.folder()) \
			+ FileCache.folder_size(Playlist.songs_folder(), Playlist.song_files_in_use())


## [param bytes] for people, e.g. "350 KB" or "14.2 MB".
static func size_text(bytes: int) -> String:
	if bytes == 0:
		return "Nothing"
	if bytes < 1 << 20:
		return "%d KB" % ceili(bytes / 1024.0)
	return "%.1f MB" % (bytes / float(1 << 20))


## Reads the characters from the folder at [param path] instead of the server. A folder
## without pictures is not used, and the popup says so.
func use_character_folder(path: String) -> void:
	if FolderCharacters.picture_names(path).is_empty():
		characters_error_label.text = "No pictures found in " + path.trim_suffix("/").get_file()
		characters_error_label.visible = true
		_fit_to_rows()
		return
	Settings.character_folder = path.trim_suffix("/")
	_show_music_source()
	characters_changed.emit()


## Uses the server's characters again, or the music folder's own if it has them.
func use_server_characters() -> void:
	Settings.character_folder = ""
	_show_music_source()
	characters_changed.emit()


func lower_cache() -> void:
	Playlist.number_of_tracks_to_preload = maxi(Playlist.number_of_tracks_to_preload - 1, 1)
	cache_label.text = str(Playlist.number_of_tracks_to_preload)


func increase_cache() -> void:
	Playlist.number_of_tracks_to_preload += 1
	cache_label.text = str(Playlist.number_of_tracks_to_preload)


func select_server(new_server: int) -> void:
	GameLog.debug("select_server")
	_use_server(new_server)


## Picks [param new_server] in the list and uses it.
func set_selected_server(new_server: int) -> void:
	GameLog.debug("set_selected_server")
	select_server_button.select(new_server)
	_use_server(new_server)


func _use_server(new_server: int) -> void:
	Settings.default_path = Settings.servers[new_server]
	Settings.selected_server = new_server
	GameLog.debug("Settings.default_path: " + Settings.default_path)
	server_changed.emit()


# Winning a game turns statistics off, so the toggles are refreshed every time this opens
func _on_visibility_changed() -> void:
	if visible:
		_update_fullscreen_button()
		show_cache_size()
		random_mode_button.select(Settings.random_mode)
		add_to_database_button.set_pressed_no_signal(Settings.add_to_stats)
	else:
		folder_error_label.visible = false
		characters_error_label.visible = false
		_fit_to_rows()


func _on_play_order_selected(order: int) -> void:
	if Settings.is_offline():
		Settings.music_folder.set_play_order(order as MusicFolder.PlayOrder)
		server_changed.emit()


# Shows where songs come from, and turns off what needs the server while offline
func _show_music_source() -> void:
	var folder: MusicFolder = Settings.music_folder
	folder_error_label.visible = false
	use_server_button.visible = folder != null
	if folder == null:
		folder_label.text = "None, using the server"
		folder_label.tooltip_text = ""
	else:
		folder_label.text = folder.display_name()
		folder_label.tooltip_text = folder.path
	play_order_row.visible = folder != null && folder.kind == MusicFolder.Kind.PREPARED_QUIZ
	characters_error_label.visible = false
	use_server_characters_button.visible = !Settings.character_folder.is_empty()
	characters_label.tooltip_text = Settings.characters_dir()
	if !Settings.character_folder.is_empty():
		characters_label.text = Settings.character_folder.get_file()
	elif !Settings.characters_dir().is_empty():
		characters_label.text = "From " + folder.display_name()
	else:
		characters_label.text = "From the server"
	for control: BaseButton in [select_server_button, random_mode_button, add_to_database_button]:
		control.disabled = folder != null
	_fit_to_rows()


# Grows or shrinks the panel to fit the rows shown, keeping it centred
func _fit_to_rows() -> void:
	var height: float = rows.get_combined_minimum_size().y + PADDING.y * 2
	settings_panel.size.y = height
	settings_panel.position.y = floorf(_panel_middle_y - height / 2)
	rows.position = PADDING
	rows.size = Vector2(settings_panel.size.x - PADDING.x * 2, height - PADDING.y * 2)


func _show_in_file_manager(dir: String) -> void:
	var error: Error = OS.shell_show_in_file_manager(dir)
	if error != OK:
		# Not every platform has a file manager to show a folder in; open it instead
		error = OS.shell_open(dir)
	if error != OK:
		GameLog.warning("Could not open %s: %s" % [dir, error_string(error)])


func _update_fullscreen_button() -> void:
	fullscreen_button.set_pressed_no_signal(Settings.fullscreen)