package nnet

import (
	"fmt"
	"git.noahlan.cn/noahlan/nnet/config"
	"git.noahlan.cn/noahlan/nnet/connection"
	"git.noahlan.cn/noahlan/ntool/nlog"
	"github.com/gorilla/websocket"
	"net/http"
	"os"
	"strings"
)

type WsConfOption func(conf config.WSServerFullConf)

func WithWSCheckOrigin(fn func(*http.Request) bool) WsConfOption {
	return func(conf config.WSServerFullConf) {
		conf.CheckOrigin = fn
	}
}

// ListenWebsocket 开始监听Websocket
func (ngin *Engine) ListenWebsocket(conf config.WSServerFullConf, opts ...WsConfOption) error {
	for _, opt := range opts {
		opt(conf)
	}

	err := ngin.setup()
	if err != nil {
		nlog.Errorf("%s failed to setup server, err:%v", ngin.LogPrefix(), err)
		return err
	}
	nlog.Infof("%s now listening websocket at %s.", ngin.LogPrefix(), conf.Addr)
	ngin.upgradeWebsocket(conf)
	if conf.IsTLS() {
		if err := http.ListenAndServeTLS(conf.Addr, conf.TLSCertificate, conf.TLSKey, nil); err != nil {
			nlog.Errorf("%s failed to listening websocket with TLS at %s %v", ngin.LogPrefix(), conf.Addr, err)
			return err
		}
	} else {
		if err := http.ListenAndServe(conf.Addr, nil); err != nil {
			nlog.Errorf("%s failed to listening websocket at %s %v", ngin.LogPrefix(), conf.Addr, err)
			return err
		}
	}
	return nil
}

func (ngin *Engine) handleWS(conn *websocket.Conn) {
	wsConn := connection.NewWSConn(conn)
	ngin.handle(wsConn)
}

func (ngin *Engine) upgradeWebsocket(conf config.WSServerFullConf) {
	upgrade := websocket.Upgrader{
		HandshakeTimeout:  conf.HandshakeTimeout,
		ReadBufferSize:    conf.ReadBufferSize,
		WriteBufferSize:   conf.WriteBufferSize,
		CheckOrigin:       conf.CheckOrigin,
		EnableCompression: conf.Compression,
	}

	path := fmt.Sprintf("/%s", strings.TrimPrefix(conf.Path, "/"))
	http.HandleFunc(path, func(writer http.ResponseWriter, request *http.Request) {
		conn, err := upgrade.Upgrade(writer, request, nil)
		if err != nil {
			nlog.Errorf("%s Upgrade failure, URI=%ng, Error=%ng", ngin.LogPrefix(), request.RequestURI, err.Error())
			return
		}
		err = ngin.goPool.Submit(func() {
			ngin.handleWS(conn)
		})
		if err != nil {
			nlog.Errorf("%s submit conn pool err: %v", ngin.LogPrefix(), err.Error())
			os.Exit(1)
		}
	})
}