21강게임 상태 관리와 저장

타이틀 → 스테이지 1 → 결과 → 스테이지 2 → ... → 엔딩

# res://autoload/game.gd
extends Node

signal score_changed(value: int)
signal gold_changed(value: int)

var score := 0:
	set(v):
		score = v
		score_changed.emit(score)

var gold := 0:
	set(v):
		gold = v
		gold_changed.emit(gold)

var current_stage := 1
var best_score := 0

func add_score(v: int) -> void:
	score += v

func add_gold(v: int) -> void:
	gold += v

func reset_run() -> void:
	score = 0
	gold = 0
	current_stage = 1

Game.add_score(100)
print(Game.gold)
Game.score_changed.connect(_on_score_changed)

get_tree().change_scene_to_file("res://scenes/stage_1.tscn")

# res://autoload/scene_manager.gd
extends CanvasLayer

@onready var fade: ColorRect = $Fade

var _loading_path := ""

func _ready() -> void:
	layer = 128                     # 항상 맨 위
	fade.color = Color(0, 0, 0, 0)
	fade.mouse_filter = Control.MOUSE_FILTER_IGNORE
	fade.visible = false

func goto(path: String, fade_time := 0.3) -> void:
	if _loading_path != "":
		return  # 전환 중이면 무시
	_loading_path = path

	# 1) 어두워지기
	fade.visible = true
	var tw := create_tween()
	tw.tween_property(fade, "color:a", 1.0, fade_time)
	await tw.finished

	# 2) 백그라운드 로딩 시작
	ResourceLoader.load_threaded_request(path)
	while true:
		var progress: Array = []
		var st := ResourceLoader.load_threaded_get_status(
			path, progress)
		if st == ResourceLoader.THREAD_LOAD_LOADED:
			break
		if st == ResourceLoader.THREAD_LOAD_FAILED:
			push_error("씬 로드 실패: " + path)
			_loading_path = ""
			return
		# progress[0] 이 0.0~1.0 진행률
		await get_tree().process_frame

	# 3) 교체
	var packed: PackedScene = \
		ResourceLoader.load_threaded_get(path)
	get_tree().change_scene_to_packed(packed)
	await get_tree().process_frame

	# 4) 밝아지기
	var tw2 := create_tween()
	tw2.tween_property(fade, "color:a", 0.0, fade_time)
	await tw2.finished
	fade.visible = false
	_loading_path = ""

# res://autoload/save_system.gd
extends Node

const PATH := "user://save.json"
const VERSION := 2

func save_game() -> bool:
	var data := {
		"version": VERSION,
		"saved_at": Time.get_unix_time_from_system(),
		"score": Game.score,
		"gold": Game.gold,
		"stage": Game.current_stage,
		"best_score": Game.best_score,
		"unlocked": Game.unlocked_items,
	}
	var f := FileAccess.open(PATH, FileAccess.WRITE)
	if f == null:
		push_error("저장 실패: %d" % FileAccess.get_open_error())
		return false
	f.store_string(JSON.stringify(data, "\t"))
	return true

func load_game() -> bool:
	if not FileAccess.file_exists(PATH):
		return false
	var f := FileAccess.open(PATH, FileAccess.READ)
	if f == null:
		return false
	var parsed = JSON.parse_string(f.get_as_text())
	if typeof(parsed) != TYPE_DICTIONARY:
		push_error("세이브 파일이 손상되었습니다")
		return false

	var d: Dictionary = parsed
	var v: int = d.get("version", 1)
	if v < VERSION:
		d = _migrate(d, v)

	Game.score = d.get("score", 0)
	Game.gold = d.get("gold", 0)
	Game.current_stage = d.get("stage", 1)
	Game.best_score = d.get("best_score", 0)
	return true

func _migrate(d: Dictionary, from: int) -> Dictionary:
	# 버전 1에는 gold가 없었다 → 기본값을 넣어준다.
	if from < 2:
		d["gold"] = d.get("gold", 0)
		d["version"] = 2
	return d

const CFG := "user://settings.cfg"

func save_settings() -> void:
	var c := ConfigFile.new()
	c.set_value("audio", "master", 0.8)
	c.set_value("audio", "bgm", 0.6)
	c.set_value("video", "fullscreen", false)
	c.set_value("game", "shake_scale", 1.0)
	c.save(CFG)

func load_settings() -> void:
	var c := ConfigFile.new()
	if c.load(CFG) != OK:
		return
	var master: float = c.get_value("audio", "master", 1.0)
	AudioServer.set_bus_volume_db(0, linear_to_db(master))

res://scenes/
├─ title.tscn      타이틀 화면
├─ stage.tscn      실제 게임
├─ result.tscn     결과 화면
└─ main_menu.tscn  설정, 도감

# 타이틀에서
func _on_start_pressed() -> void:
	Game.reset_run()
	SceneManager.goto("res://scenes/stage.tscn")

# 게임 오버 시
func _on_player_died() -> void:
	Game.best_score = maxi(Game.best_score, Game.score)
	SaveSystem.save_game()
	await get_tree().create_timer(1.2).timeout
	SceneManager.goto("res://scenes/result.tscn")

# 결과 화면에서
func _on_retry_pressed() -> void:
	Game.reset_run()
	SceneManager.goto("res://scenes/stage.tscn")