import json
import os
import socket
import ssl
import sys
import uuid

from aiomqtt import Client

from config.redis import redis_client
from models.MqttTopic import MqttTopic

# ================= 配置区域 =================
MQTT_BROKER = "ai.ronsunny.cn"
MQTT_PORT = 8093
MQTT_PASSWORD = "123456"
TLS_CONTEXT = ssl.create_default_context()

# 默认连接后要订阅的 topic 配置
DEFAULT_SUBSCRIPTIONS = [
    MqttTopic.from_parts(
        project=None,
        domain="status",
        device_type="edge",
        device_id=None,
        resource="info",
    )
]
# ===========================================

DEVICE_ID = None
MQTT_CLIENT: Client | None = None  # 全局客户端

# Windows 平台下切换到 SelectorEventLoop
if sys.platform.lower() == "win32" or os.name.lower() == "nt":
    from asyncio import set_event_loop_policy, WindowsSelectorEventLoopPolicy

    set_event_loop_policy(WindowsSelectorEventLoopPolicy())


def get_device_id_simple():
    try:
        with open("/etc/machine-id") as f:
            mid = f.read().strip()
            if mid:
                return mid
    except Exception:
        pass
    hostname = socket.gethostname()
    mac = uuid.getnode()
    mac_str = ":".join(f"{(mac >> ele) & 0xff:02x}" for ele in range(40, -1, -8))
    return f"{hostname}|{mac_str}"


# todo  这里需要订阅状态信息 设备发送信息 这里回复 vue前端发送指令 后端发送指令 设备接收指令
# ------------------ MQTT 封装 ------------------


async def mqtt_publish(
    project: str,
    domain: str,
    device_type: str,
    device_id: str,
    resource: str,
    payload: str,
    qos: int = 1,
):
    """发布消息（使用全局客户端）"""
    if not MQTT_CLIENT:
        raise RuntimeError("MQTT client is not initialized")
    topic = f"{project}/{domain}/{device_type}/{device_id}/{resource}"
    await MQTT_CLIENT.publish(topic, payload, qos=qos)
    print(f"Published to {topic}: {payload}")


async def mqtt_publish_multiple(
    targets: list[dict], resource: str, payload: str, qos: int = 1
):
    """群发消息"""
    for target in targets:
        await mqtt_publish(
            domain=target["domain"],
            device_type=target["device_type"],
            device_id=target["device_id"],
            resource=resource,
            payload=payload,
            qos=qos,
        )


async def _mqtt_handle_messages():
    """后台循环处理消息"""
    if not MQTT_CLIENT:
        return
    async for message in MQTT_CLIENT.messages:
        topic = MqttTopic(message.topic)
        print("收到消息：" + str(topic))

        # 处理基础状态信息
        if topic.domain == "status" and topic.resource == "info":
            payload = json.loads(message.payload.decode())
            redis_client.set_device_info(topic.device_id, payload)


async def mqtt_client_async():
    global DEVICE_ID, MQTT_CLIENT
    DEVICE_ID = get_device_id_simple()
    print("服务端EMQX账号：", DEVICE_ID)
    async with Client(
        MQTT_BROKER,
        port=MQTT_PORT,
        username=DEVICE_ID,
        password=MQTT_PASSWORD,
        tls_context=TLS_CONTEXT,
        identifier=DEVICE_ID,
    ) as client:
        MQTT_CLIENT = client  # 保存全局客户端
        print("MQTT client connected")

        # 订阅默认 topic
        for topic in DEFAULT_SUBSCRIPTIONS:
            await MQTT_CLIENT.subscribe(topic.to_topic())
            print(f"Subscribed to default topic: {topic.to_topic()}")

        # 启动消息处理循环
        await _mqtt_handle_messages()


# ------------------ 示例主程序 ------------------


# async def main():
#     await mqtt_client_async()
#
#     # 示例：发布消息
#     await mqtt_publish("status", "edge", DEVICE_ID, "heartbeat", '{"alive":true}')
#
#     # 示例：群发
#     targets = [
#         {"domain": "cmd", "device_type": "edge", "device_id": "edge01"},
#         {"domain": "cmd", "device_type": "edge", "device_id": "edge02"},
#     ]
#     await mqtt_publish_multiple(targets, "restart", '{"action":"restart"}')