class_name Game
extends Node

## TODO: sicherungskasten minigames (Kabel verbinden, oder draufhauen und geht wieder)


const SAVE_DIR: String = "user://saves/%s/"
const SAVE_PATH: String = SAVE_DIR + "%s"
const INITIAL_SAVE_DATA: SaveData = preload("res://src/initial_save_data.tres")

static var is_debug: bool = true

@export_file("*.tscn", "*.scn") var main_menu_path: String = "uid://7v62dybcabgw"

var current_save_slot: int = 0
var current_save_data: SaveData = INITIAL_SAVE_DATA.duplicate()
var world: World
var main_menu: MainMenu

@onready var loading_screen: LoadingScreen = $LoadingScreen
@onready var world_container: Node = $WorldContainer


static func _static_init() -> void:
	is_debug = OS.is_debug_build() or Engine.is_editor_hint()


static func debug_draw(draw_shape: String, args: Array) -> void:
	if is_debug and Engine.has_singleton(&"DebugDraw3D"):
		Engine.get_singleton(&"DebugDraw3D").callv("draw_" + draw_shape, args)


func _ready() -> void:
	load_main_menu()


func load_game(save_data: SaveData, save_slot: int) -> void:
	current_save_data = save_data.duplicate()
	current_save_slot = save_slot
	load_world(current_save_data.current_world, false)


func save_game() -> Error:
	if not is_instance_valid(world):
		return ERR_DOES_NOT_EXIST

	var save_slot: String = str(current_save_slot)
	var file_name: String = "save_data.tres"

	if is_instance_valid(world):
		current_save_data.current_world = ResourceUID.path_to_uid(world.scene_file_path)

	DirAccess.make_dir_recursive_absolute(SAVE_DIR % save_slot)
	return ResourceSaver.save(current_save_data, SAVE_PATH % [save_slot, file_name])


#func _ready() -> void:
	#await load_world("res://src/worlds/exposition/exposition.tscn")
	#await get_tree().create_timer(5.0, false).timeout
	#await unload_world()
	#await loading_screen.fade_out()
	#await get_tree().create_timer(3.0, false).timeout
	#_ready()


func load_world(world_path: String, save_previous: bool = true, load_from_save: bool = true) -> Error:
	if not ResourceLoader.exists(world_path, "PackedScene"):
		return ERR_FILE_NOT_FOUND

	await loading_screen.fade_in()

	unload_main_menu()
	unload_world(save_previous)

	var loader := InteractiveLoader.create_oneshot(self)
	var loaded_scene: PackedScene = await loader.load_threaded(world_path)
	world = loaded_scene.instantiate() as World

	if not is_instance_valid(world):
		loading_screen.fade_out()
		return ERR_INVALID_DATA

	if load_from_save:
		world.world_state = load_world_state(world_path)

	world.change_world_requested.connect(load_world)
	world.world_unload_requested.connect(_on_unload_world_request)

	world_container.add_child.call_deferred(world)
	await world.loaded
	loading_screen.fade_out()
	return OK


func unload_world(do_save: bool = true) -> void:
	if not is_instance_valid(world):
		return

	if do_save:
		save_world_state()

	world.process_mode = Node.PROCESS_MODE_DISABLED
	await loading_screen.fade_in()
	world.queue_free()


func save_world_state() -> Error:
	if not is_instance_valid(world):
		return ERR_DOES_NOT_EXIST

	world.update_world_state()
	var world_state: WorldState = world.world_state
	var save_slot: String = str(current_save_slot)
	var file_name: String = _get_world_save_file_name_from_world_path(world_state.world_path)
	print("File name: ", file_name)
	print(SAVE_PATH % [save_slot, file_name])
	DirAccess.make_dir_recursive_absolute(SAVE_DIR % save_slot)
	save_game()
	return ResourceSaver.save(world_state, SAVE_PATH % [save_slot, file_name])


func load_world_state(world_path: String) -> WorldState:
	var save_slot: String = str(current_save_slot)
	var file_name: String = _get_world_save_file_name_from_world_path(world_path)
	var file_path: String = SAVE_PATH % [save_slot, file_name]
	if not ResourceLoader.exists(file_path):
		return null

	return ResourceLoader.load(file_path)


func load_main_menu() -> void:
	var loader := InteractiveLoader.create_oneshot(self)
	var loaded_scene: PackedScene = await loader.load_threaded(main_menu_path)
	var _main_menu: MainMenu = loaded_scene.instantiate()
	_main_menu.load_game_request.connect(load_game)
	_main_menu.quit_request.connect(quit_game)
	main_menu = _main_menu
	world_container.add_child(main_menu)


func unload_main_menu() -> void:
	if is_instance_valid(main_menu):
		main_menu.queue_free()


func quit_game() -> void:
	await loading_screen.fade_in()
	get_tree().quit()


func _on_unload_world_request(do_save: bool) -> void:
	await unload_world(do_save)

	if do_save:
		save_game()

	await load_main_menu()
	loading_screen.fade_out()


func _get_world_save_file_name_from_world_path(world_path: String) -> String:
	world_path = ResourceUID.path_to_uid(world_path)
	print("World path: ", world_path)

	if world_path.begins_with("res://"):
		return world_path.get_file().replace(".tscn", ".tres").replace(".scn", ".res")

	return world_path.replace("uid://", "") + ".tres"