package coordinator

import (
	"log"
	"net/http"

	"github.com/gorilla/websocket"
)

var upgrader = websocket.Upgrader{} // use default options

func Serve(c *Coordinator) {
	http.HandleFunc("/ws", func(w http.ResponseWriter, r *http.Request) {
		serveWs(c, w, r)
	})
	err := http.ListenAndServe(":7636", nil)
	if err != nil {
		log.Fatal("ListenAndServe: ", err)
	}
}

func serveWs(c *Coordinator, w http.ResponseWriter, r *http.Request) {
	// Upgrade our raw HTTP connection to a websocket based one
	conn, err := upgrader.Upgrade(w, r, nil)
	if err != nil {
		log.Print("Error during connection upgradation:", err)
		return
	}
	defer conn.Close()

	// The event loop
	for {
		var cmd SessionCommand
		err := conn.ReadJSON(&cmd)
		if err != nil {
			log.Println("Error during message reading:", err)
			break
		}
		log.Printf("Received: %s", cmd)
		resp := c.Coordinate(&cmd)
		err = conn.WriteJSON(resp)
		if err != nil {
			log.Println("Error during message writing:", err)
			break
		}
		if resp.Result == SessionRespLeft {
			break
		}
	}
}