refactor: constanten redirect vervangen door enum

frontend/src/router/index.ts

@@ -14,6 +14,7 @@ import UserHomePage from "@/views/homepage/UserHomePage.vue";
 import SingleTheme from "@/views/SingleTheme.vue";
 import LearningObjectView from "@/views/learning-paths/learning-object/LearningObjectView.vue";
 import authService from "@/services/auth/auth-service";
+import {allowRedirect, Redirect} from "@/utils/redirect.ts";
 
 const router = createRouter({
     history: createWebHistory(import.meta.env.BASE_URL),
@@ -144,10 +145,10 @@ router.beforeEach(async (to, _from, next) => {
     if (to.meta.requiresAuth) {
         if (!authService.isLoggedIn.value && !(await authService.loadUser())) {
             const path = to.fullPath;
-            if (path !== "/") {
+            if (allowRedirect(path)) {
-                localStorage.setItem("redirectAfterLogin", path);
+                localStorage.setItem(Redirect.AFTER_LOGIN_KEY, path);
             }
-            next("/login");
+            next(Redirect.LOGIN);
         } else {
             next();
         }

frontend/src/utils/redirect.ts

@@ -0,0 +1,14 @@
+export enum Redirect {
+    AFTER_LOGIN_KEY = "redirectAfterLogin",
+    HOME = "/user",
+    LOGIN = "/login",
+    ROOT = "/"
+}
+
+const NOT_ALLOWED_REDIRECTS = new Set<Redirect>([
+    Redirect.HOME, Redirect.ROOT, Redirect.LOGIN
+]);
+
+export function allowRedirect(path: string): boolean {
+    return !NOT_ALLOWED_REDIRECTS.has(path as Redirect);
+}

frontend/src/views/CallbackPage.vue

@@ -3,6 +3,7 @@
     import { useI18n } from "vue-i18n";
     import { onMounted, ref, type Ref } from "vue";
     import auth from "../services/auth/auth-service.ts";
+    import {Redirect} from "@/utils/redirect.ts";
 
     const { t } = useI18n();
 
@@ -11,12 +12,12 @@
     const errorMessage: Ref<string | null> = ref(null);
 
     async function redirectPage(): Promise<void> {
-        const redirectUrl = localStorage.getItem("redirectAfterLogin");
+        const redirectUrl = localStorage.getItem(Redirect.AFTER_LOGIN_KEY);
         if (redirectUrl) {
-            localStorage.removeItem("redirectAfterLogin");
+            localStorage.removeItem(Redirect.AFTER_LOGIN_KEY);
             await router.replace(redirectUrl);
         } else {
-            await router.replace("/user"); // Redirect to theme page
+            await router.replace(Redirect.HOME);
         }
     }