package core

import (
	"fmt"
	"github.com/gorilla/websocket"
	"html/template"
	"log"
	"net/http"
)

func echo(sub Subscriber) func(w http.ResponseWriter, r *http.Request) {
	var upgrader = websocket.Upgrader{} // use default options
	return func(w http.ResponseWriter, r *http.Request) {
		fmt.Println("upgrading to ws")
		c, err := upgrader.Upgrade(w, r, nil)
		if err != nil {
			log.Print("upgrade:", err)
			return
		}
		//defer c.Close()
		go func() {
			for {
				if _, _, err := c.NextReader(); err != nil {
					c.Close()
					break
				}
			}
		}()

		dispatcherId, channel := sub.Subscribe()
		defer sub.Unsubscribe(dispatcherId)
		for {
			log.Println("")
			//if err != nil {
			//	log.Println("read:", err)
			//	break
			//}
			cmsg := <-channel
			err = c.WriteMessage(websocket.TextMessage, []byte(cmsg))
			if err != nil {
				log.Println("write:", err)

				break
			}
		}
	}
}

func home(w http.ResponseWriter, r *http.Request) {
	//var homeTemplate = template.Must(template.NewDispatcher("").ParseFiles("index.html"))
	tpl, err := template.ParseFiles("index.html")
	if err != nil {
		log.Fatalln(err)
	}
	err = tpl.Execute(w, "ws://"+r.Host+"/echo")
	if err != nil {
		log.Fatalln(err)
	}
}

func NewHttpServer(sub Subscriber, httpPort string) {
	http.HandleFunc("/echo", echo(sub))
	http.HandleFunc("/", home)
	http.Handle("/static/", http.FileServer(http.Dir(".")))

	log.Fatal(http.ListenAndServe(httpPort, nil))
}