hub.go

package main

import (
    "fmt"
    "net/http"
    "time"
    "net/url"
    "github.com/gorilla/websocket"
    "strings"
    "strconv"
)

var (
    //Pass connections between threads
    conchan chan *websocket.Conn
    //Master quit channel (not implemented)
    quit chan int16
    //Base HTTP server for websocket upgrade
    serv = &http.Server{Addr: "localhost:3000", ReadTimeout: 10 * time.Second, WriteTimeout: 10 * time.Second}
    //Upgrader
    wsupgr = websocket.Upgrader{CheckOrigin: checkReq}
    //Shows how many users are
    // [0] - in the lobby
    // [1] - being matched
    // [2] - in game
    states = []uint64{0, 0, 0}
)

//Makes shure the origin of the request is not compromised
func checkReq(r *http.Request) bool{
    u, err := url.Parse(r.Header["Origin"][0])
    if err != nil {
        return false
    }
    return strings.HasPrefix(r.Host, u.Host)
}

//Accepts a http request, translates it to a websocket, and passes it into the rest of the code
func hndl(w http.ResponseWriter, r *http.Request) {
    c, err := wsupgr.Upgrade(w, r, nil)
    if err != nil {
        fmt.Println("[ERR]", err)
        return
    }
    lobby(c)
}

//Returns a string representation of [states]
func getUsers() string {
    return fmt.Sprintf("%s:%s:%s", strconv.FormatUint(states[0]), strconv.FormatUint(states[1]), strconv.FormatUint(states[2]))
}

//Accepts a websocket connection and performs basic tasks
func lobby(conn *websocket.Conn){
    states[0]++
    fmt.Println("In Lobby")
    conn.WriteJSON(DataJSON{"lobby", ""})
    var dat DataJSON
    for {
        err := conn.ReadJSON(&dat)
        if err != nil {
            states[0]--
            fmt.Println("[ALERT]", err)
            conn.Close()
            return
        }
        switch dat.Data{
            case "match":
                fmt.Println("Matching")
                conn.WriteJSON(DataJSON{"matching", ""})
                conchan <- conn
                return
            case "state":
                fmt.Println("State")
                conn.WriteJSON(DataJSON{"matching", getUsers()})
            default:
                break
        }
    }
}

//Starting point for program
func main() {
    conchan = make(chan *websocket.Conn)
    quit = make(chan int16)
    go grouper(conchan, quit)
    http.HandleFunc("/lobby", hndl)
    fmt.Println("Error: ", serv.ListenAndServe())
}