package ws

import (
	"context"
	"github.com/fox/fox/ksync"
	"github.com/fox/fox/log"
	"github.com/gorilla/websocket"
	"net/http"
	"sync"
	"time"
)

type IOnFunc interface {
	OnMessage(msg []byte) error
}

type Client struct {
	conn     *websocket.Conn
	sendChan chan *wsMessage
	ctx      context.Context
	cancel   context.CancelFunc
	wg       sync.WaitGroup
	onFunc   IOnFunc
}

func NewClient(url string, onFunc IOnFunc) (*Client, error) {
	dialer := websocket.DefaultDialer
	dialer.HandshakeTimeout = 30 * time.Second
	conn, _, err := dialer.Dial(url, http.Header{"User-Agent": {"MyClient/1.0"}})
	if err != nil {
		return nil, err
	}

	ctx, cancel := context.WithCancel(context.Background())

	return &Client{
		conn:     conn,
		sendChan: make(chan *wsMessage, 100),
		ctx:      ctx,
		cancel:   cancel,
		onFunc:   onFunc,
	}, nil
}

func (c *Client) Start() {
	c.wg.Add(2)
	ksync.GoSafe(c.readLoop, nil)
	ksync.GoSafe(c.writeLoop, nil)
	ksync.GoSafe(c.heartbeatLoop, nil)
}

/*
readLoop暂时没有好的办法及时退出协程，c.conn.ReadMessage()是阻塞式，导致协程无法及时catch到关闭信号
如果在ReadMessage前调用SetReadDeadline设置超时，它会在超时后将底部连接状态标记为已损坏，后续ReadMessage会触发崩溃
*/
func (c *Client) readLoop() {
	//defer c.wg.Done()
	for {
		select {
		case <-c.ctx.Done():
			log.Debug("readLoop 收到关闭信号")
			return
		default:
			messageType, message, err := c.conn.ReadMessage()
			if err != nil {
				//log.Error(fmt.Sprintf("读取错误:%v", err))
				c.NotifyStop()
				return
			}

			switch messageType {
			case websocket.PingMessage:
				c.sendChan <- &wsMessage{messageType: websocket.PongMessage, data: []byte("pong")}
			case websocket.PongMessage:

			case websocket.TextMessage, websocket.BinaryMessage:
				_ = c.onFunc.OnMessage(message)

			case websocket.CloseMessage:
				log.Debug("收到关闭帧")
				c.NotifyStop()
				return
			}
		}
	}
}

func (c *Client) SendMsg(data []byte) {
	c.sendChan <- &wsMessage{messageType: websocket.BinaryMessage, data: data}
}

func (c *Client) writeLoop() {
	defer c.wg.Done()
	for {
		select {
		case msg := <-c.sendChan:
			switch msg.messageType {
			case websocket.PingMessage:
				_ = c.conn.WriteMessage(websocket.PingMessage, []byte("ping"))
			case websocket.PongMessage:
				_ = c.conn.WriteMessage(websocket.PongMessage, []byte("pong"))
			default:
				_ = c.conn.WriteMessage(msg.messageType, msg.data)
			}
		case <-c.ctx.Done():
			//log.Debug("writeLoop 收到关闭信号")
			// 发送关闭帧
			_ = c.conn.WriteControl(
				websocket.CloseMessage,
				websocket.FormatCloseMessage(websocket.CloseNormalClosure, ""),
				time.Now().Add(10*time.Second),
			)
			return
		}
	}
}

func (c *Client) heartbeatLoop() {
	defer c.wg.Done()
	ticker := time.NewTicker(25 * time.Second)
	defer ticker.Stop()

	for {
		select {
		case <-ticker.C:
			c.sendChan <- &wsMessage{messageType: websocket.PingMessage, data: []byte("ping")}
		case <-c.ctx.Done():
			//log.Debug("heartbeatLoop 收到关闭信号")
			return
		}
	}
}

func (c *Client) WaitStop() {
	c.wg.Wait()
}

func (c *Client) NotifyStop() {
	c.cancel()
	_ = c.conn.Close()
}