module change

public/js/auth.js

@@ -0,0 +1,58 @@
+// 🔐 Password hashing using jsSHA
+function hashPassword(password) {
+  const shaObj = new jsSHA("SHA-256", "TEXT");
+  shaObj.update(password);
+  return shaObj.getHash("HEX");
+}
+
+// 🌐 Load users from server
+let users = [];
+
+// 🔓 Verify user login
+async function verifyLogin() {
+  const uname = document.getElementById('username').value.trim();
+  const pw = document.getElementById('password').value;
+  const hash = hashPassword(pw);
+  const msg = document.getElementById('loginMessage');
+
+  try {
+    const res = await fetch('/verifyUser', {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ username: uname, hash })
+    });
+
+    if (!res.ok) {
+      msg.textContent = "Invalid username or password.";
+      return;
+    }
+
+    const user = await res.json();
+    localStorage.setItem('loggedInUser', JSON.stringify(user));
+    msg.textContent = '';
+    setupSession(user);
+  } catch (err) {
+    console.error("Login error:", err);
+    msg.textContent = "Login failed. Please try again.";
+  }
+}
+
+// 🚪 Log out user
+function logoutUser() {
+  localStorage.removeItem('loggedInUser');
+
+  document.getElementById('adminPanel').classList.add('hidden');
+  document.getElementById('studentPanel').classList.add('hidden');
+  document.getElementById('nav').classList.add('hidden');
+  document.getElementById('loginPanel').classList.remove('hidden');
+  document.getElementById('username').value = '';
+  document.getElementById('password').value = '';
+
+  const roleBanner = document.getElementById('roleBanner');
+  roleBanner.classList.add('hidden');
+  roleBanner.classList.remove('admin', 'student');
+  roleBanner.textContent = '';
+
+  const loginMessage = document.getElementById('loginMessage');
+  if (loginMessage) loginMessage.textContent = '';
+}