class_name BaseLevel
extends Node2D

# 基础关卡脚本
# 负责处理通用的关卡逻辑，如玩家生成
const CHAT_UI_SCENE: PackedScene = preload("res://scenes/ui/ChatUI.tscn")
const CHAT_UI_NODE_NAME: String = "ChatUI"
const UI_LAYER_NODE_NAME: String = "UILayer"
const UI_LAYER_ORDER: int = 10

func _ready():
	_ensure_chat_ui()

	# 延时一帧确保所有子节点就绪
	call_deferred("_spawn_player")
	
	# 连接到多人会话
	# 获取当前场景名字作为 Session ID
	_current_session_id = SceneManager.get_current_scene_name()
	if _current_session_id == "":
		_current_session_id = "square"
	
	# 如果是私人场景，生成唯一的 Session ID (e.g., room_123)
	if _current_session_id in PRIVATE_SCENES:
		_current_session_id = _current_session_id + "_" + str(AuthManager.current_user_id)
	
	# 如果 WebSocket 已连接，直接加入
	if LocationManager._socket.get_ready_state() == WebSocketPeer.STATE_OPEN:

		_join_session_with_player(_current_session_id)
	else:
		# 否则等待连接成功信号
		LocationManager.connected_to_server.connect(func(): _join_session_with_player(_current_session_id))

	# 连接远程玩家相关信号
	LocationManager.session_joined.connect(_on_session_joined)
	LocationManager.user_joined.connect(_on_user_joined)
	LocationManager.user_left.connect(_on_user_left)
	LocationManager.position_updated.connect(_on_position_updated)

func _ensure_chat_ui() -> void:
	var ui_layer := get_node_or_null(UI_LAYER_NODE_NAME) as CanvasLayer
	if ui_layer == null:
		ui_layer = CanvasLayer.new()
		ui_layer.name = UI_LAYER_NODE_NAME
		ui_layer.layer = UI_LAYER_ORDER
		add_child(ui_layer)

	var chat_ui := ui_layer.get_node_or_null(CHAT_UI_NODE_NAME)
	if chat_ui == null:
		chat_ui = CHAT_UI_SCENE.instantiate()
		chat_ui.name = CHAT_UI_NODE_NAME
		ui_layer.add_child(chat_ui)

	if chat_ui.has_method("hide_chat"):
		chat_ui.call_deferred("hide_chat")

var remote_players: Dictionary = {} # userId -> RemotePlayer instance
var remote_player_scene = preload("res://scenes/characters/remote_player.tscn")
var _player_spawned: bool = false # Track if local player has been spawned
var _local_player: Node = null # Reference to the local player node
var _position_update_timer: float = 0.0 # Throttle timer for position updates
var _current_session_id: String = "" # Cache session ID to avoid race condition on exit
const POSITION_UPDATE_INTERVAL: float = 0.125 # Send at most 8 times per second
const PRIVATE_SCENES = ["room"] # List of scenes that should be private instances

func _on_session_joined(data: Dictionary):
	# 对账远程玩家列表，使用 position.mapId 过滤
	if not data.has("users"):
		return
	
	var current_map = _current_session_id
	if current_map == "":
		current_map = SceneManager.get_current_scene_name()
		if current_map == "":
			current_map = "square"
	
	# 1. 收集服务器返回的、且 mapId 匹配当前场景的用户ID
	var valid_user_ids: Array = []
	var valid_users: Dictionary = {}  # userId -> user data
	
	for user in data.users:
		if not user.has("userId") or str(user.userId) == str(AuthManager.current_user_id):
			continue
		
		# 检查 position.mapId 是否匹配当前场景
		var user_map_id = ""
		if user.has("position") and user.position != null:
			if typeof(user.position) == TYPE_DICTIONARY and user.position.has("mapId"):
				user_map_id = str(user.position.mapId)
		
		if user_map_id == current_map:
			var uid = str(user.userId)
			valid_user_ids.append(uid)
			valid_users[uid] = user
	
	# 2. 清理幽灵：移除本地有但不在有效列表中的玩家
	var local_user_ids = remote_players.keys()
	for user_id in local_user_ids:
		if str(user_id) not in valid_user_ids:
			_remove_remote_player(user_id)
	
	# 3. 添加或更新有效的玩家
	for uid in valid_user_ids:
		var user = valid_users[uid]
		if remote_players.has(uid):
			# 已存在，更新位置
			_update_remote_player_position(user)
		else:
			_add_remote_player(user)

func _on_user_joined(data: Dictionary):
	var user = data.get("user", {})
	if user.has("userId"):
		if user.userId == AuthManager.current_user_id:
			return
		
		# 将 position 数据合并到 user 字典中，以便 _add_remote_player 统一处理
		if data.has("position"):
			user["position"] = data.position
			
		_add_remote_player(user)

func _on_user_left(data: Dictionary):
	var user_id = data.get("userId")
	if user_id:
		_remove_remote_player(user_id)

func _on_position_updated(data: Dictionary):
	var user_id = data.get("userId")
	
	if user_id and remote_players.has(user_id):
		var player = remote_players[user_id]
		# 数据可能直接是位置（扁平）或者包含在 position 字段中
		# 根据后端协议: { userId:..., position: {x,y...}, ... }
		var pos_data = data.get("position", {})
		if pos_data.is_empty():
			pos_data = data
		
		# 检查 mapId 是否匹配当前场景
		if pos_data.has("mapId") and str(pos_data.mapId) != "":
			var current_map = _current_session_id
			if current_map == "":
				current_map = "square"
			
			if str(pos_data.mapId) != current_map:
				_remove_remote_player(user_id)
				return
			
		if player.has_method("update_position") and pos_data.has("x") and pos_data.has("y"):
			player.update_position(Vector2(pos_data.x, pos_data.y))

func _add_remote_player(user_data: Dictionary):
	var user_id = str(user_data.get("userId", ""))
	if user_id == "":
		return
	
	# 防止重复创建
	if remote_players.has(user_id):
		return
		
	var remote_player = remote_player_scene.instantiate()
	
	# 使用统一的 setup 方法
	if remote_player.has_method("setup"):
		remote_player.setup(user_data)
	else:
		# 回退到手动设置位置
		remote_player.position = Vector2.ZERO
		if user_data.has("position"):
			var p = user_data.position
			if p.has("x") and p.has("y"):
				remote_player.position = Vector2(p.x, p.y)
	
	# 添加到场景玩家容器
	if has_node("Objects/Players"):
		$Objects/Players.add_child(remote_player)
	else:
		add_child(remote_player)
		
	remote_players[user_id] = remote_player

func _remove_remote_player(user_id):
	var uid = str(user_id)
	if remote_players.has(uid):
		var player = remote_players[uid]
		if is_instance_valid(player):
			player.queue_free()
		remote_players.erase(uid)

func _update_remote_player_position(user: Dictionary):
	var user_id = str(user.get("userId", ""))
	var player = remote_players.get(user_id)
	if not player or not is_instance_valid(player):
		return
	if user.has("position"):
		var pos = user.position
		if pos.has("x") and pos.has("y") and player.has_method("update_position"):
			player.update_position(Vector2(pos.x, pos.y))

func _join_session_with_player(session_id: String):
	# 检查是否有Token，如果没有则等待
	if LocationManager._auth_token == "":
		# 轮询等待Token就绪 (简单重试机制)
		await get_tree().create_timer(0.5).timeout
		_join_session_with_player(session_id)
		return

	# 等待玩家生成完毕
	if not _player_spawned or not _local_player:
		await get_tree().process_frame
		_join_session_with_player(session_id)
		return

	var pos = _local_player.global_position if is_instance_valid(_local_player) else Vector2.ZERO

	LocationManager.join_session(session_id, pos)

	# 进入会话后立即同步一次位置
	await get_tree().create_timer(0.1).timeout
	LocationManager.send_position_update(session_id, pos)

func _process(delta):
	# 发送位置更新 (节流机制)
	if not _player_spawned or not _local_player:
		return # Wait for player to be spawned

	if LocationManager._socket.get_ready_state() != WebSocketPeer.STATE_OPEN:
		return # WebSocket not connected

	if not is_instance_valid(_local_player):
		return # Player was freed

	# 检查 velocity 属性
	if not "velocity" in _local_player:
		return

	# 只有在移动时才更新计时器和发送
	if _local_player.velocity.length() > 0:
		_position_update_timer += delta
		if _position_update_timer >= POSITION_UPDATE_INTERVAL:
			_position_update_timer = 0.0
			var map_id = _current_session_id if _current_session_id != "" else "square"
			LocationManager.send_position_update(map_id, _local_player.global_position)
			
func _spawn_player():
	# 1. 确定出生位置
	var spawn_pos = Vector2.ZERO
	var spawn_name = SceneManager.get_next_spawn_name()
	
	# 查找逻辑：优先查找名为 spawn_name 的节点，其次找 DefaultSpawn
	var target_node_name = spawn_name if spawn_name != "" else "DefaultSpawn"
	var marker_node = null
	
	# 策略 A: 在 SpawnPoints 容器中查找
	if has_node("SpawnPoints"):
		marker_node = $SpawnPoints.get_node_or_null(target_node_name)
	
	# 策略 B: 如果没找到，在当前节点(根节点)下查找
	if marker_node == null:
		marker_node = get_node_or_null(target_node_name)
		
	# 如果找到了标记点，使用其位置
	if marker_node:
		spawn_pos = marker_node.global_position
	else:
		# 策略 C: 检查 SceneManager 是否有备用坐标
		var pos_param = SceneManager.get_next_scene_position()
		if pos_param != null:
			spawn_pos = pos_param
		else:
			push_warning("BaseLevel: 出生点 '%s' 不存在，使用默认坐标 (0, 0)" % target_node_name)
	
	# 2. 实例化玩家
	var player_scene = preload("res://scenes/characters/player.tscn")
	var player = player_scene.instantiate()
	player.global_position = spawn_pos
	
	# 添加到场景
	# 如果有Objects/Players容器则添加进去，否则直接添加到当前节点
	if has_node("Objects/Players"):
		$Objects/Players.add_child(player)
	else:
		add_child(player)
	
	_local_player = player
	_player_spawned = true