package auth

import (
	"net/http"

	"github.com/gorilla/context"
)

type key int

const ukey key = 0

// AuthMiddleware get User from session and put it in context
type Middleware struct {
	authorizer *Authorizer
}

func NewMiddleware(authorizer *Authorizer) *Middleware {
	return &Middleware{authorizer}
}

func (m *Middleware) ServeHTTP(w http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
	user, err := m.authorizer.CurrentUser(w, r)
	if err != nil {
		panic(err)
	}
	context.Set(r, ukey, user)
	next(w, r)
}

type MiddlewareRole struct {
	authorizer *Authorizer
	role       string
}

func NewMiddlewareRole(authorizer *Authorizer, role string) *MiddlewareRole {
	return &MiddlewareRole{authorizer, role}
}

func (m *MiddlewareRole) ServeHTTP(w http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
	user := GetCurrentUser(r)

	if user == nil || !user.HasRole(m.role) {
		//TODO: redirect to login page and save wanted page
		return
	}

	next(w, r)
}

func GetCurrentUser(r *http.Request) User {
	u := context.Get(r, ukey)
	if u == nil {
		return nil
	}
	user, ok := u.(User)
	if !ok {
		panic("Invalid user type")
	}
	return user
}