init frontend

excalidraw/excalidraw-app/hooks/useAuth.ts

@@ -0,0 +1,41 @@
+import { useEffect } from "react";
+import { jwtDecode } from "jwt-decode";
+import { User } from "../app-jotai";
+
+export const useAuth = (setUser: (user: User | null) => void) => {
+  useEffect(() => {
+    // Check for token in URL params, which happens after GitHub login redirect.
+    const searchParams = new URLSearchParams(window.location.search);
+    const token = searchParams.get("token");
+    if (token) {
+      localStorage.setItem("token", token);
+      // Clean the token from the URL.
+      window.history.replaceState({}, document.title, window.location.pathname);
+    }
+
+    const storedToken = localStorage.getItem("token");
+    if (storedToken) {
+      try {
+        const decodedToken: any = jwtDecode(storedToken);
+        // Check if token is expired.
+        if (decodedToken.exp * 1000 > Date.now()) {
+          setUser({
+            id: decodedToken.userId,
+            githubId: decodedToken.githubId,
+            login: decodedToken.login,
+            avatarUrl: decodedToken.avatarUrl,
+            name: decodedToken.name,
+          });
+        } else {
+          // Token is expired, remove it.
+          localStorage.removeItem("token");
+          setUser(null);
+        }
+      } catch (error) {
+        console.error("Invalid token:", error);
+        localStorage.removeItem("token");
+        setUser(null);
+      }
+    }
+  }, [setUser]);
+};