extends Node
class_name DialogueHistoryManager
## 对话历史管理器
## 负责保存、加载和管理对话历史记录

# 历史记录存储
var dialogue_histories: Dictionary = {}  # character_id -> Array[Dictionary]
var max_history_per_character: int = 100
var history_file_path: String = "user://dialogue_history.json"

# 信号
signal history_loaded()
signal history_saved()

func _ready():
	"""初始化对话历史管理器"""
	load_history()
	print("DialogueHistoryManager initialized")

## 添加消息到历史记录
func add_message_to_history(character_id: String, sender: String, message: String, timestamp: float = 0.0) -> void:
	"""
	添加消息到指定角色的对话历史
	@param character_id: 角色ID
	@param sender: 发送者（"player" 或角色ID）
	@param message: 消息内容
	@param timestamp: 时间戳（0表示使用当前时间）
	"""
	if timestamp <= 0:
		timestamp = Time.get_unix_time_from_system()
	
	# 确保角色历史记录存在
	if not dialogue_histories.has(character_id):
		dialogue_histories[character_id] = []
	
	var history = dialogue_histories[character_id]
	
	# 创建消息记录
	var message_record = {
		"sender": sender,
		"message": message,
		"timestamp": timestamp,
		"id": generate_message_id()
	}
	
	# 添加到历史记录
	history.append(message_record)
	
	# 限制历史记录长度
	if history.size() > max_history_per_character:
		history.pop_front()
	
	# 自动保存（异步）
	call_deferred("save_history")

## 获取角色的对话历史
func get_character_history(character_id: String, limit: int = 0) -> Array[Dictionary]:
	"""
	获取指定角色的对话历史
	@param character_id: 角色ID
	@param limit: 限制返回的消息数量（0表示返回全部）
	@return: 消息历史数组
	"""
	if not dialogue_histories.has(character_id):
		return []
	
	var history = dialogue_histories[character_id]
	
	if limit <= 0 or limit >= history.size():
		return history.duplicate()
	
	# 返回最近的消息
	return history.slice(history.size() - limit, history.size())

## 获取最近的对话记录
func get_recent_conversations(limit: int = 10) -> Array[Dictionary]:
	"""
	获取最近的对话记录（按时间排序）
	@param limit: 限制返回的对话数量
	@return: 最近对话的摘要数组
	"""
	var recent_conversations = []
	
	for character_id in dialogue_histories:
		var history = dialogue_histories[character_id]
		if history.size() > 0:
			var last_message = history[-1]  # 最后一条消息
			recent_conversations.append({
				"character_id": character_id,
				"last_message": last_message.message,
				"last_sender": last_message.sender,
				"timestamp": last_message.timestamp,
				"message_count": history.size()
			})
	
	# 按时间戳排序（最新的在前）
	recent_conversations.sort_custom(func(a, b): return a.timestamp > b.timestamp)
	
	# 限制数量
	if limit > 0 and recent_conversations.size() > limit:
		recent_conversations = recent_conversations.slice(0, limit)
	
	return recent_conversations

## 搜索对话历史
func search_messages(query: String, character_id: String = "") -> Array[Dictionary]:
	"""
	在对话历史中搜索消息
	@param query: 搜索关键词
	@param character_id: 指定角色ID（空字符串表示搜索所有角色）
	@return: 匹配的消息数组
	"""
	var results = []
	var search_query = query.to_lower()
	
	var characters_to_search = []
	if character_id.is_empty():
		characters_to_search = dialogue_histories.keys()
	else:
		characters_to_search = [character_id]
	
	for char_id in characters_to_search:
		if not dialogue_histories.has(char_id):
			continue
		
		var history = dialogue_histories[char_id]
		for message_record in history:
			if message_record.message.to_lower().contains(search_query):
				var result = message_record.duplicate()
				result["character_id"] = char_id
				results.append(result)
	
	# 按时间戳排序（最新的在前）
	results.sort_custom(func(a, b): return a.timestamp > b.timestamp)
	
	return results

## 清除角色的对话历史
func clear_character_history(character_id: String) -> void:
	"""
	清除指定角色的对话历史
	@param character_id: 角色ID
	"""
	if dialogue_histories.has(character_id):
		dialogue_histories.erase(character_id)
		save_history()

## 清除所有对话历史
func clear_all_history() -> void:
	"""清除所有对话历史"""
	dialogue_histories.clear()
	save_history()

## 保存历史记录到文件
func save_history() -> void:
	"""保存对话历史到本地文件"""
	var file = FileAccess.open(history_file_path, FileAccess.WRITE)
	if file:
		var json_string = JSON.stringify(dialogue_histories)
		file.store_string(json_string)
		file.close()
		history_saved.emit()
		print("Dialogue history saved")
	else:
		print("Failed to save dialogue history")

## 从文件加载历史记录
func load_history() -> void:
	"""从本地文件加载对话历史"""
	if not FileAccess.file_exists(history_file_path):
		print("No dialogue history file found, starting fresh")
		return
	
	var file = FileAccess.open(history_file_path, FileAccess.READ)
	if file:
		var json_string = file.get_as_text()
		file.close()
		
		var json = JSON.new()
		var parse_result = json.parse(json_string)
		
		if parse_result == OK:
			dialogue_histories = json.data
			history_loaded.emit()
			print("Dialogue history loaded: ", dialogue_histories.size(), " characters")
		else:
			print("Failed to parse dialogue history JSON")
	else:
		print("Failed to open dialogue history file")

## 生成消息ID
func generate_message_id() -> String:
	"""生成唯一的消息ID"""
	var timestamp = Time.get_unix_time_from_system()
	var random = randi()
	return "msg_%d_%d" % [timestamp, random]

## 获取统计信息
func get_statistics() -> Dictionary:
	"""
	获取对话历史统计信息
	@return: 统计信息字典
	"""
	var total_messages = 0
	var total_characters = dialogue_histories.size()
	var oldest_message_time = 0.0
	var newest_message_time = 0.0
	
	for character_id in dialogue_histories:
		var history = dialogue_histories[character_id]
		total_messages += history.size()
		
		if history.size() > 0:
			var first_msg_time = history[0].timestamp
			var last_msg_time = history[-1].timestamp
			
			if oldest_message_time == 0.0 or first_msg_time < oldest_message_time:
				oldest_message_time = first_msg_time
			
			if newest_message_time == 0.0 or last_msg_time > newest_message_time:
				newest_message_time = last_msg_time
	
	return {
		"total_messages": total_messages,
		"total_characters": total_characters,
		"oldest_message_time": oldest_message_time,
		"newest_message_time": newest_message_time,
		"file_path": history_file_path
	}

## 导出历史记录
func export_history(export_path: String, character_id: String = "") -> bool:
	"""
	导出对话历史到指定文件
	@param export_path: 导出文件路径
	@param character_id: 指定角色ID（空字符串表示导出所有）
	@return: 是否成功
	"""
	var export_data = {}
	
	if character_id.is_empty():
		export_data = dialogue_histories
	elif dialogue_histories.has(character_id):
		export_data[character_id] = dialogue_histories[character_id]
	else:
		print("Character not found: ", character_id)
		return false
	
	var file = FileAccess.open(export_path, FileAccess.WRITE)
	if file:
		var json_string = JSON.stringify(export_data)
		file.store_string(json_string)
		file.close()
		print("History exported to: ", export_path)
		return true
	else:
		print("Failed to export history to: ", export_path)
		return false