import json
import threading
import time
from json import JSONDecodeError
from typing import Callable, Optional

import websocket


class ServerException(Exception):
    pass


class Device:
    def __init__(self, device_id: str, device_key: str,
                 on_msg_callback: Optional[Callable[[str, any], None]] = lambda point, value : print(point, value),
                 on_error_callback: Optional[Callable[[Exception], None]] = lambda error: print(error),
                 base_url: str = "wss://api.makergen.cn"):
        """
        创建一个设备对象。需要调用connect方法才能真正连接。
        :param device_id: 设备ID，在控制台设备管理中显示
        :param device_key: Device Key，在控制台设备管理中显示
        :param on_msg_callback: 当收到消息后的回调。接收两个参数，第一个参数为控制点，字符串型；第二个参数为控制值，任意类型
        :param on_error_callback: 当遇到错误时的回调。接收一个参数，为错误对象；若遇到服务器或页面发送的消息不合规，传入ServerException对象
        :param base_url: makergen的基础URL，通常为wss://api.makergen.cn
        """
        url = f"{base_url if base_url[-1] == '/' else base_url + '/'}ws/device/{device_id}?key={device_key}"
        print(url)
        self.ws = websocket.WebSocketApp(
            url,
            on_open=self._on_open,
            on_message=self._on_message,
            on_close=self._on_close,
            on_error=self._on_error,
        )
        self.on_msg_callback = on_msg_callback if on_msg_callback is not None else lambda _, __ : None
        self.on_error_callback = on_error_callback if on_error_callback is not None else lambda _ : None
        self.is_connected = False
        self._connect_event = threading.Event()

    def _on_open(self, ws):
        self.is_connected = True
        self._connect_event.set()

    def _on_close(self, ws, close_status_code, close_msg):
        self.is_connected = False
        self._connect_event.clear()

    def _on_message(self, ws, message):
        try:
            message_str = json.loads(message)["payload"]
            self.on_msg_callback(message_str["point"], message_str["value"])
        except (KeyError, JSONDecodeError):
            self.on_error_callback(ServerException("Page or server sent an invalid message"))
        except Exception as e:
            self.on_error_callback(e)

    def _on_error(self, ws, error):
        self.on_error_callback(error)

    def send_data(self, point: str, value: str):
        self.ws.send(json.dumps({
            "type": "data",
            "payload": {
                "point": point,
                "value": value
            },
            "timestamp": int(time.time() * 1000)
        }))

    def connect(self, timeout: float = 5.0):
        """
        在新线程中运行客户端循环（推荐）
        """
        self._connect_event.clear()
        wst = threading.Thread(target=self.ws.run_forever)
        wst.daemon = True
        wst.start()
        start_time = time.time()
        if not self._connect_event.wait(timeout=timeout):
            self.on_error_callback(TimeoutError(f"WebSocket connection timed out after {timeout} seconds"))

def main_loop(self):
        """
        在当前线程中运行客户端循环（不推荐）
        """
        self.ws.run_forever()