import asyncio
import json

import uvicorn
from fastapi import FastAPI
import paho.mqtt.client as mqtt
from pydantic import BaseModel
from starlette.middleware.cors import CORSMiddleware


class BaseResponse(BaseModel):
    code: int = 200
    msg: str = "success"


app = FastAPI()

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

class MQTTClient:
    def __init__(self, broker, port, topic, username, password):
        self.broker = broker
        self.port = port
        self.topic = topic
        self.username = username
        self.password = password
        # 千万不要指定client_id 不然死翘翘
        self.client = mqtt.Client()
        self.client.username_pw_set(self.username, self.password)

    def push(self):
        self.client.publish(self.topic, payload=json.dumps({"msg": "open_led"}, ensure_ascii=False),
                            qos=0)
        self.client.publish(self.topic, payload=json.dumps({"msg": "push_stream"}, ensure_ascii=False),
                            qos=0)

    def close(self):
        self.client.publish(self.topic, payload=json.dumps({"msg": "close_stream"}, ensure_ascii=False),
                            qos=0)
        self.client.publish(self.topic, payload=json.dumps({"msg": "close_led"}, ensure_ascii=False),
                            qos=0)

    def start(self):
        self.client.connect(self.broker, self.port)


user_sched = {}

async def close(username, device):
    # 倒计时600秒
    await asyncio.sleep(35)
    print(username + "结束推流")
    user_sched.pop(username)
    close_stream(username, device)


async def task_start(username, device):
    print(username + "创建结束推流定时任务")
    task = asyncio.create_task(close(username, device))
    user_sched[username] = task


@app.get("/start/video/{username}/{device}")
async def start(username, device):
    try:
        # 如果定时任务不存在，那么直接进行推流。当用户退出界面时，创建任务
        if username not in user_sched:
            print(username + "开始推流")
            push_stream(username, device)
        # 如果定时任务存在，那么取消上次的任务。当用户退出界面时，创建任务
        else:
            t = user_sched[username]
            # 取消任务
            if t is not None:
                print(username + "取消定时任务")
                t.cancel()
        return BaseResponse(code=200, msg="success")
    except Exception as e:
        return BaseResponse(code=500, msg=str(e))


@app.get("/stop/video/{username}/{device}")
async def stop(username, device):
    try:
        await task_start(username, device)
        return BaseResponse(code=200, msg="success")
    except Exception as e:
        return BaseResponse(code=500, msg=str(e))


def push_stream(username, device):
    MQTT = MQTTClient(broker, port, device, username, username)
    MQTT.start()
    MQTT.push()


def close_stream(username, device):
    MQTT = MQTTClient(broker, port, device, username, username)
    MQTT.start()
    MQTT.close()


if __name__ == '__main__':
    broker = 'mqtt.lihaink.cn'
    port = 1883
    uvicorn.run(app, host="0.0.0.0", port=8000)