// Package client webSocket 客户端
package client

import (
	"errors"
	"fmt"
	"net/url"
	"strings"

	"golang.org/x/net/websocket"
)

const (
	connRetry = 3 // 建立连接重试次数
)

// WebSocket webSocket
type WebSocket struct {
	conn    *websocket.Conn
	URLLink string
	URL     *url.URL
	IsSsl   bool
}

// NewWebSocket new
func NewWebSocket(urlLink string) (ws *WebSocket) {
	var isSsl bool
	if strings.HasPrefix(urlLink, "wss://") {
		isSsl = true
	}
	u, err := url.Parse(urlLink)
	// 解析失败
	if err != nil {
		panic(err)
	}
	ws = &WebSocket{
		URLLink: urlLink,
		URL:     u,
		IsSsl:   isSsl,
	}
	return
}

// getLink 获取连接
func (w *WebSocket) getLink() (link string) {
	return w.URLLink
}

// getOrigin 获取源连接
func (w *WebSocket) getOrigin() (origin string) {
	origin = "http://"
	if w.IsSsl {
		origin = "https://"
	}
	origin = fmt.Sprintf("%s%s/", origin, w.URL.Host)
	return
}

// Close 关闭
func (w *WebSocket) Close() (err error) {
	if w == nil {
		return
	}
	if w.conn == nil {
		return
	}
	return w.conn.Close()
}

// GetConn 获取连接
func (w *WebSocket) GetConn() (err error) {
	var (
		conn *websocket.Conn
		i    int
	)
	for i = 0; i < connRetry; i++ {
		conn, err = websocket.Dial(w.getLink(), "", w.getOrigin())
		if err != nil {
			fmt.Println("GetConn 建立连接失败 in...", i, err)
			continue
		}
		w.conn = conn
		return
	}
	if err != nil {
		fmt.Println("GetConn 建立连接失败", i, err)
	}
	return
}

// Write 发送数据
func (w *WebSocket) Write(body []byte) (err error) {
	if w.conn == nil {
		err = errors.New("未建立连接")
		return
	}
	_, err = w.conn.Write(body)
	if err != nil {
		fmt.Println("发送数据失败:", err)
		return
	}
	return
}

// Read 接收数据
func (w *WebSocket) Read() (msg []byte, err error) {
	if w.conn == nil {
		err = errors.New("未建立连接")
		return
	}
	msg = make([]byte, 512)
	n, err := w.conn.Read(msg)
	if err != nil {
		fmt.Println("接收数据失败:", err)
		return nil, err
	}
	return msg[:n], nil
}