extends Node

# ============================================================================
# SettingsManager.gd - 游戏设置偏好管理器
# ============================================================================
# 统一应用账号级设置，并向运行中的 UI、聊天和角色系统广播变更。
# 设置持久化以后端账号 profile 为准，本管理器不再读写 user:// 配置文件。
# ============================================================================

const BASE_VIEWPORT_SIZE: Vector2i = Vector2i(1920, 1440)

const DEFAULT_SETTINGS: Dictionary = {
	"master_volume": 0.80,
	"music_volume": 0.60,
	"effects_volume": 0.90,
	"ui_scale": 1.00,
	"fullscreen": false,
	"show_interaction_hints": false,
	"show_name_always": false,
	"show_chat_bubbles": true,
	"world_notifications": true,
	"private_notifications": true,
	"friend_request_notifications": true,
	"allow_nearby_private": true,
	"allow_nearby_friend_requests": true,
	"mute_ui_sfx": false,
}

var _settings: Dictionary = DEFAULT_SETTINGS.duplicate(true)

func _ready() -> void:
	_connect_auth_events()
	reset_to_defaults(false)
	apply_all_settings()

func load_settings() -> void:
	_settings = DEFAULT_SETTINGS.duplicate(true)
	apply_all_settings()
	_emit_settings_changed()

func save_settings() -> bool:
	_emit_settings_changed()
	return true

func get_default_settings() -> Dictionary:
	return DEFAULT_SETTINGS.duplicate(true)

func get_settings() -> Dictionary:
	return _settings.duplicate(true)

func set_settings(settings: Dictionary, saveImmediately: bool = true) -> void:
	for key in DEFAULT_SETTINGS.keys():
		if settings.has(key):
			_settings[key] = settings[key]
	apply_all_settings()
	if saveImmediately:
		save_settings()
	else:
		_emit_settings_changed()

func apply_account_settings(settings: Dictionary) -> void:
	set_settings(settings, false)

func reset_to_defaults(emitChanged: bool = true) -> void:
	_settings = DEFAULT_SETTINGS.duplicate(true)
	apply_all_settings()
	if emitChanged:
		_emit_settings_changed()

func set_setting(key: String, value: Variant, saveImmediately: bool = true) -> void:
	if not DEFAULT_SETTINGS.has(key):
		return
	_settings[key] = value
	apply_all_settings()
	if saveImmediately:
		save_settings()
	else:
		_emit_settings_changed()

func get_setting(key: String, fallback: Variant = null) -> Variant:
	return _settings.get(key, fallback if fallback != null else DEFAULT_SETTINGS.get(key))

func get_bool(key: String) -> bool:
	return bool(_settings.get(key, DEFAULT_SETTINGS.get(key, false)))

func get_float(key: String) -> float:
	return float(_settings.get(key, DEFAULT_SETTINGS.get(key, 0.0)))

func apply_all_settings() -> void:
	_apply_fullscreen_setting()
	_apply_audio_settings()
	_apply_ui_scale_setting()

func _apply_audio_settings() -> void:
	_apply_bus_volume("Master", get_float("master_volume"))
	_apply_bus_volume("Music", get_float("music_volume"))
	_apply_bus_volume("SFX", get_float("effects_volume"))

func _apply_bus_volume(busName: String, value: float) -> void:
	var busIndex := AudioServer.get_bus_index(busName)
	if busIndex < 0:
		return
	var clamped := clampf(value, 0.0, 1.0)
	AudioServer.set_bus_mute(busIndex, clamped <= 0.001)
	if clamped > 0.001:
		AudioServer.set_bus_volume_db(busIndex, linear_to_db(clamped))

func _apply_fullscreen_setting() -> void:
	if DisplayServer.get_name() == "headless":
		return
	var fullscreen := get_bool("fullscreen")
	DisplayServer.window_set_mode(DisplayServer.WINDOW_MODE_FULLSCREEN if fullscreen else DisplayServer.WINDOW_MODE_WINDOWED)

func _apply_ui_scale_setting() -> void:
	var viewport := get_tree().root
	if viewport == null:
		return
	var scale := clampf(get_float("ui_scale"), 0.8, 1.2)
	viewport.content_scale_size = Vector2i(
		int(round(float(BASE_VIEWPORT_SIZE.x) / scale)),
		int(round(float(BASE_VIEWPORT_SIZE.y) / scale))
	)

func _emit_settings_changed() -> void:
	var eventSystem := get_node_or_null("/root/EventSystem")
	if eventSystem != null:
		eventSystem.call("emit_event", EventNames.SETTINGS_CHANGED, get_settings())

func _connect_auth_events() -> void:
	var eventSystem := get_node_or_null("/root/EventSystem")
	if eventSystem == null:
		return
	eventSystem.call("connect_event", EventNames.AUTH_LOGOUT, _on_auth_logout, self)

func _on_auth_logout(_data: Variant = null) -> void:
	reset_to_defaults()