// Utility: get users object from localStorage (or empty object)
function getUsers() {
  const users = localStorage.getItem("users");
  return users ? JSON.parse(users) : {};
}

// Utility: save users object back to localStorage
function saveUsers(users) {
  localStorage.setItem("users", JSON.stringify(users));
}

// SIGNUP PAGE LOGIC
const signupForm = document.getElementById("signupForm");
if (signupForm) {
  const signupMessage = document.getElementById("signupMessage");

  signupForm.addEventListener("submit", (e) => {
    e.preventDefault();

    const username = document.getElementById("newUsername").value.trim();
    const password = document.getElementById("newPassword").value;
    const confirmPassword = document.getElementById("confirmPassword").value;

    if (!username || !password || !confirmPassword) {
      signupMessage.style.color = "red";
      signupMessage.textContent = "❌ Please fill in all fields.";
      return;
    }

    if (password !== confirmPassword) {
      signupMessage.style.color = "red";
      signupMessage.textContent = "❌ Passwords do not match.";
      return;
    }

    const users = getUsers();

    if (users[username]) {
      signupMessage.style.color = "red";
      signupMessage.textContent = "❌ Username already exists.";
      return;
    }

    users[username] = password;
    saveUsers(users);

    signupMessage.style.color = "green";
    signupMessage.textContent = "✅ Account created! Redirecting to login...";

    setTimeout(() => {
      window.location.href = "index.html";
    }, 1500);
  });
}

// LOGIN PAGE LOGIC
const loginForm = document.getElementById("loginForm");
if (loginForm) {
  const loginMessage = document.getElementById("loginMessage");

  loginForm.addEventListener("submit", (e) => {
    e.preventDefault();

    const username = document.getElementById("loginUsername").value.trim();
    const password = document.getElementById("loginPassword").value;

    if (!username || !password) {
      loginMessage.style.color = "red";
      loginMessage.textContent = "❌ Please enter both username and password.";
      return;
    }

    const users = getUsers();

    if (users[username] && users[username] === password) {
      loginMessage.style.color = "green";
      loginMessage.textContent = `✅ Welcome back, ${username}!`;

      // Store logged-in user and redirect
      localStorage.setItem("loggedInUser", username);

      setTimeout(() => {
        window.location.href = "dashboard.html";
      }, 1000);
    } else {
      loginMessage.style.color = "red";
      loginMessage.textContent = "❌ Invalid username or password.";
    }
  });
}