package handler

import (
	"encoding/json"
	"fmt"
	"fusenapi/constants"
	"fusenapi/server/websocket/internal/svc"
	"fusenapi/server/websocket/internal/types"
	"fusenapi/utils/auth"
	"github.com/google/uuid"
	"github.com/gorilla/websocket"
	"github.com/zeromicro/go-zero/core/logx"
	"net/http"
	"sync"
	"time"
)

var (
	//升级
	upgrade = websocket.Upgrader{
		//允许跨域
		CheckOrigin: func(r *http.Request) bool {
			return true
		},
	}
	//连接map池
	mapConn = sync.Map{}
)

// 每个连接的连接属性
type wsConnectItem struct {
	conn      *websocket.Conn //websocket的连接
	closeChan chan struct{}   //关闭chan
	isClose   bool            //是否已经关闭
	flag      string
	inChan    chan interface{} //接受消息缓冲通道
	property  interface{}      //属性
}

func DataTransferHandler(svcCtx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		//升级websocket
		conn, err := upgrade.Upgrade(w, r, nil)
		if err != nil {
			logx.Error("http upgrade websocket err:", err)
			return
		}
		defer conn.Close()
		rsp := types.DataTransferRsp{}
		// 解析JWT token,并对空用户进行判断
		claims, err := svcCtx.ParseJwtToken(r)
		// 如果解析JWT token出错,则返回未授权的JSON响应并记录错误消息
		if err != nil {
			rsp.MsgType = constants.WEBSOCKET_UNAUTH
			rsp.Message = "unAuth"
			b, _ := json.Marshal(rsp)
			_ = conn.WriteMessage(websocket.TextMessage, b)
			return
		}
		if claims != nil {
			// 从token中获取对应的用户信息
			_, err = auth.GetUserInfoFormMapClaims(claims)
			// 如果获取用户信息出错,则返回未授权的JSON响应并记录错误消息
			if err != nil {
				rsp.MsgType = constants.WEBSOCKET_UNAUTH
				rsp.Message = "unAuth!!"
				b, _ := json.Marshal(rsp)
				_ = conn.WriteMessage(websocket.TextMessage, b)
				return
			}
		} else {
			// 如果claims为nil,则认为用户身份为白板用户
			rsp.MsgType = constants.WEBSOCKET_UNAUTH
			rsp.Message = "unAuth!!!"
			b, _ := json.Marshal(rsp)
			_ = conn.WriteMessage(websocket.TextMessage, b)
			return
		}
		//生成连接唯一标识
		flag := uuid.New().String() + time.Now().Format("20060102150405")
		ws := wsConnectItem{
			conn:      conn,
			flag:      flag,
			closeChan: make(chan struct{}, 1),
			inChan:    make(chan interface{}, 1000),
			isClose:   false,
		}
		//保存连接
		mapConn.Store(flag, ws)
		defer ws.close()
		//把连接成功消息发回去
		rsp.MsgType = constants.WEBSOCKET_CONNECT_SUCCESS
		rsp.Message = flag
		b, _ := json.Marshal(rsp)
		conn.WriteMessage(websocket.TextMessage, b)
		//循环读客户端信息
		go ws.readLoop()
		//推消息到云渲染
		go ws.sendLoop()
		//心跳
		for {
			time.Sleep(time.Second * 3)
			select {
			case <-ws.closeChan:
				return
			default:
				//发送心跳信息
				rsp.MsgType = constants.WEBSOCKET_HEARTBEAT
				rsp.Message = "heartbeat"
				b, _ = json.Marshal(rsp)
				if err = conn.WriteMessage(websocket.TextMessage, b); err != nil {
					logx.Error("发送心跳信息异常，关闭连接:", flag, err)
					ws.close()
					return
				}
			}
		}

	}
}

// 关闭连接
func (w *wsConnectItem) close() {
	logx.Info("websocket:", w.flag, " is closing...")
	w.conn.Close()
	mapConn.Delete(w.flag)
	if !w.isClose {
		w.isClose = true
		close(w.closeChan)
		close(w.inChan)
	}
	logx.Info("websocket:", w.flag, " is closed")
}

// 接受客户端发来的消息
func (w *wsConnectItem) readLoop() {
	for {
		select {
		case <-w.closeChan: //如果关闭了
			return
		default:
			_, data, err := w.conn.ReadMessage()
			if err != nil {
				logx.Error("接受信息错误:", err)
				//关闭连接
				w.close()
				return
			}
			//消息传入缓冲通道
			w.inChan <- data
		}
	}
}

// 把收到的消息发往不同的地方处理
func (w *wsConnectItem) sendLoop() {
	for {
		select {
		case <-w.closeChan:
			return
		case data := <-w.inChan:
			fmt.Println(data)
		}
	}
}