hello-agents/code/chapter15/Helloagents-AI-Town/helloagents-ai-town/scripts/api_client.gd

# API客户端 - 与FastAPI后端通信
extends Node

# 信号定义
signal chat_response_received(npc_name: String, message: String)
signal chat_error(error_message: String)
signal npc_status_received(dialogues: Dictionary)
signal npc_list_received(npcs: Array)

# HTTP请求节点
var http_chat: HTTPRequest
var http_status: HTTPRequest
var http_npcs: HTTPRequest

func _ready():
	# 创建HTTP请求节点
	http_chat = HTTPRequest.new()
	http_status = HTTPRequest.new()
	http_npcs = HTTPRequest.new()
	
	add_child(http_chat)
	add_child(http_status)
	add_child(http_npcs)
	
	# 连接信号
	http_chat.request_completed.connect(_on_chat_request_completed)
	http_status.request_completed.connect(_on_status_request_completed)
	http_npcs.request_completed.connect(_on_npcs_request_completed)
	
	print("[INFO] API客户端初始化完成")

# ==================== 对话API ====================
func send_chat(npc_name: String, message: String) -> void:
	"""发送对话请求"""
	var data = {
		"npc_name": npc_name,
		"message": message
	}
	
	var json_string = JSON.stringify(data)
	var headers = ["Content-Type: application/json"]
	
	print("[API] POST /chat -> ", data)
	
	var error = http_chat.request(
		Config.API_CHAT,
		headers,
		HTTPClient.METHOD_POST,
		json_string
	)
	
	if error != OK:
		print("[ERROR] 发送对话请求失败: ", error)
		chat_error.emit("网络请求失败")

func _on_chat_request_completed(_result: int, response_code: int, _headers: PackedStringArray, body: PackedByteArray) -> void:
	"""处理对话响应"""
	if response_code != 200:
		print("[ERROR] 对话请求失败: HTTP ", response_code)
		chat_error.emit("服务器错误: " + str(response_code))
		return
	
	var json = JSON.new()
	var parse_result = json.parse(body.get_string_from_utf8())
	
	if parse_result != OK:
		print("[ERROR] 解析响应失败")
		chat_error.emit("响应解析失败")
		return
	
	var response = json.data
	
	if response.has("success") and response["success"]:
		var npc_name = response["npc_name"]
		var msg = response["message"]
		print("[INFO] 收到NPC回复: ", npc_name, " -> ", msg)
		chat_response_received.emit(npc_name, msg)
	else:
		chat_error.emit("对话失败")

# ==================== NPC状态API ====================
func get_npc_status() -> void:
	"""获取NPC状态"""
	# 检查是否正在处理请求
	if http_status.get_http_client_status() != HTTPClient.STATUS_DISCONNECTED:
		print("[WARN] NPC状态请求正在处理中,跳过本次请求")
		return

	print("[API] GET /npcs/status")

	var error = http_status.request(Config.API_NPC_STATUS)

	if error != OK:
		print("[ERROR] 获取NPC状态失败: ", error)

func _on_status_request_completed(_result: int, response_code: int, _headers: PackedStringArray, body: PackedByteArray) -> void:
	"""处理NPC状态响应"""
	if response_code != 200:
		print("[ERROR] NPC状态请求失败: HTTP ", response_code)
		return
	
	var json = JSON.new()
	var parse_result = json.parse(body.get_string_from_utf8())
	
	if parse_result != OK:
		print("[ERROR] 解析NPC状态失败")
		return
	
	var response = json.data
	
	if response.has("dialogues"):
		var dialogues = response["dialogues"]
		print("[INFO] 收到NPC状态更新: ", dialogues.size(), "个NPC")
		npc_status_received.emit(dialogues)

# ==================== NPC列表API ====================
func get_npc_list() -> void:
	"""获取NPC列表"""
	print("[API] GET /npcs")
	
	var error = http_npcs.request(Config.API_NPCS)
	
	if error != OK:
		print("[ERROR] 获取NPC列表失败: ", error)

func _on_npcs_request_completed(_result: int, response_code: int, _headers: PackedStringArray, body: PackedByteArray) -> void:
	"""处理NPC列表响应"""
	if response_code != 200:
		print("[ERROR] NPC列表请求失败: HTTP ", response_code)
		return
	
	var json = JSON.new()
	var parse_result = json.parse(body.get_string_from_utf8())
	
	if parse_result != OK:
		print("[ERROR] 解析NPC列表失败")
		return
	
	var response = json.data
	
	if response.has("npcs"):
		var npcs = response["npcs"]
		print("[INFO] 收到NPC列表: ", npcs.size(), "个NPC")
		npc_list_received.emit(npcs)