import paho.mqtt.client as mqtt
import json
from datetime import datetime

# MQTT 配置
MQTT_BROKER = "localhost"  # 本地MQTT代理地址
MQTT_PORT = 1883  # 默认MQTT端口
MQTT_TOPIC = "test/topic"  # 订阅的主题
MQTT_CLIENT_ID = "message_processor"  # 客户端ID


def on_connect(client, userdata, flags, rc):
    """连接回调函数"""
    print(f"Connected to MQTT broker with result code {rc}")
    # 订阅主题
    client.subscribe(MQTT_TOPIC)
    print(f"Subscribed to topic: {MQTT_TOPIC}")


def on_message(client, userdata, msg):
    """消息接收回调函数"""
    try:
        # 1. 接收原始消息
        raw_message = msg.payload.decode('utf-8')
        print(f"\n[{datetime.now()}] Received raw message:")
        print(raw_message)

        # 2. 二次处理 - 这里示例处理JSON格式消息
        processed_data = process_message(raw_message)

        # 3. 输出处理结果
        print("\nProcessed result:")
        print(json.dumps(processed_data, indent=2, ensure_ascii=False))

    except Exception as e:
        print(f"Error processing message: {e}")


def process_message(raw_message):
    """
    消息二次处理函数
    这里可以根据实际需求实现各种处理逻辑
    """
    try:
        # 尝试解析为JSON
        data = json.loads(raw_message)

        # 示例处理：添加处理时间戳
        processed = {
            "original_data": data,
            "processing_timestamp": datetime.now().isoformat(),
            "status": "processed"
        }

        # 可以在这里添加更多处理逻辑
        # 例如：数据转换、计算、过滤等

        return processed

    except json.JSONDecodeError:
        # 如果不是JSON，按文本处理
        return {
            "text_content": raw_message,
            "word_count": len(raw_message.split()),
            "char_count": len(raw_message)
        }


def main():
    # 创建MQTT客户端
    client = mqtt.Client(client_id=MQTT_CLIENT_ID, clean_session=True)

    # 设置回调函数
    client.on_connect = on_connect
    client.on_message = on_message

    try:
        # 连接到MQTT代理
        client.connect(MQTT_BROKER, MQTT_PORT, keepalive=60)

        print(f"Starting MQTT client to listen on {MQTT_BROKER}:{MQTT_PORT}, topic: {MQTT_TOPIC}")
        print("Waiting for messages...")

        # 启动网络循环
        client.loop_forever()

    except KeyboardInterrupt:
        print("\nDisconnecting from MQTT broker...")
        client.disconnect()
    except Exception as e:
        print(f"Error: {e}")


if __name__ == "__main__":
    main()