package main
 
import (
    "fmt"
    "gorilla/mux"
    "gorilla/securecookie"
    "net/http"
)
 
 
var cookieHandler = securecookie.New(
    securecookie.GenerateRandomKey(64),
    securecookie.GenerateRandomKey(32))
 
func getSession(request *http.Request) (yourName string) {
    if cookie, err := request.Cookie("your-name"); err == nil {
        cookieValue := make(map[string]string)
        if err = cookieHandler.Decode("your-name", cookie.Value, &cookieValue); err == nil {
            yourName = cookieValue["your-name"]
        }
    }
    return yourName
}
 
func setSession(yourName string, response http.ResponseWriter) {
    value := map[string]string{
        "your-name": yourName,
    }
    if encoded, err := cookieHandler.Encode("your-name", value); err == nil {
        cookie := &http.Cookie{
            Name:  "your-name",
            Value: encoded,
            Path:  "/",
			MaxAge: 3600,
        }
        http.SetCookie(response, cookie)
    }
}
 
func clearSession(response http.ResponseWriter) {
    cookie := &http.Cookie{
        Name:   "your-name",
        Value:  "",
        Path:   "/",
        MaxAge: -1,
    }
    http.SetCookie(response, cookie)
}
 
 
func setSessionHandler(response http.ResponseWriter, request *http.Request) {
    name := request.FormValue("name")    
    redirectTarget := "/"
    if name != "" {
        setSession(name, response)
        redirectTarget = "/page1"
    }
    http.Redirect(response, request, redirectTarget, 302)
}
 

 
func clearSessionHandler(response http.ResponseWriter, request *http.Request) {
    clearSession(response)
    http.Redirect(response, request, "/", 302)
}
 

 
const indexPage = `
Sesssion Test

    Your Name
    
    Set Sesssion

`
 
func indexPageHandler(response http.ResponseWriter, request *http.Request) {
    fmt.Fprintf(response, indexPage)
}
 
 
const frontPage = `
Check Sesssion

Your Name: %s

    Clear Sesssion

`
 
func sessionPageHandler(response http.ResponseWriter, request *http.Request) {
    yourName := getSession(request)
    if yourName != "" {
        fmt.Fprintf(response, frontPage, yourName)
    } else {
        http.Redirect(response, request, "/", 302)
    }
}
 
 
var router = mux.NewRouter()
 
func main() {
 
    router.HandleFunc("/", indexPageHandler)
    router.HandleFunc("/page1", sessionPageHandler)
	router.HandleFunc("/page2", sessionPageHandler)
	router.HandleFunc("/page3", sessionPageHandler)
	router.HandleFunc("/page4", sessionPageHandler)
 
    router.HandleFunc("/start", setSessionHandler).Methods("POST")
    router.HandleFunc("/clear", clearSessionHandler).Methods("POST")
 
    http.Handle("/", router)
    http.ListenAndServe(":8080", nil)
}