// ============================================================
// AUTH.JS — Login, Register, 2FA, Session Management
// ============================================================

// Wait for DOM to be fully ready
document.addEventListener('DOMContentLoaded', function() {

  var authScreen = document.getElementById('auth-screen');
  var mainApp = document.getElementById('main-app');
  var loginForm = document.getElementById('login-form');
  var registerForm = document.getElementById('register-form');
  var forgotForm = document.getElementById('forgot-form');
  var userName = document.getElementById('user-name');

  var TOKEN_KEY = 'ped_scribe_token';
  var USER_KEY = 'ped_scribe_user';

  console.log('[Auth] Initializing...');
  console.log('[Auth] authScreen:', !!authScreen);
  console.log('[Auth] mainApp:', !!mainApp);
  console.log('[Auth] loginForm:', !!loginForm);
  console.log('[Auth] registerForm:', !!registerForm);

  // Make sure forms are visible/hidden correctly on load
  showLoginForm();

  // Check for saved session
  var savedToken = localStorage.getItem(TOKEN_KEY);
  if (savedToken) {
    console.log('[Auth] Found saved token, verifying...');
    fetch('/api/auth/me', {
      headers: { 'Authorization': 'Bearer ' + savedToken }
    })
    .then(function(r) {
      if (r.ok) return r.json();
      throw new Error('expired');
    })
    .then(function(data) {
      if (data && data.user) {
        console.log('[Auth] Token valid, logging in as:', data.user.email);
        enterApp(data.user, savedToken);
      } else {
        console.log('[Auth] Token invalid');
        clearSession();
      }
    })
    .catch(function() {
      console.log('[Auth] Token expired or invalid');
      clearSession();
    });
  }

  // ---- HELPER FUNCTIONS ----

  function showLoginForm() {
    if (loginForm) loginForm.style.display = 'block';
    if (registerForm) registerForm.style.display = 'none';
    if (forgotForm) forgotForm.style.display = 'none';
  }

  function showRegisterForm() {
    if (loginForm) loginForm.style.display = 'none';
    if (registerForm) registerForm.style.display = 'block';
    if (forgotForm) forgotForm.style.display = 'none';
  }

  function showForgotForm() {
    if (loginForm) loginForm.style.display = 'none';
    if (registerForm) registerForm.style.display = 'none';
    if (forgotForm) forgotForm.style.display = 'block';
  }

  function enterApp(user, token) {
    window.AUTH_TOKEN = token;
    localStorage.setItem(TOKEN_KEY, token);
    localStorage.setItem(USER_KEY, JSON.stringify(user));

    if (authScreen) authScreen.style.display = 'none';
    if (mainApp) {
      mainApp.style.display = 'block';
      mainApp.className = mainApp.className.replace('hidden', '').trim();
    }
    if (userName) userName.textContent = user.name || user.email;

    // Show admin tab for admins
    var adminTabBtn = document.getElementById('admin-tab-btn');
    if (adminTabBtn) {
      if (user.role === 'admin') {
        adminTabBtn.classList.remove('hidden');
      } else {
        adminTabBtn.classList.add('hidden');
      }
    }

    console.log('[Auth] ✅ Entered app as:', user.email, 'Role:', user.role);
  }

  function exitApp() {
    clearSession();
    if (authScreen) authScreen.style.display = 'flex';
    if (mainApp) mainApp.style.display = 'none';
    var adminTabBtn = document.getElementById('admin-tab-btn');
    if (adminTabBtn) adminTabBtn.classList.add('hidden');
    showLoginForm();
  }

  function clearSession() {
    localStorage.removeItem(TOKEN_KEY);
    localStorage.removeItem(USER_KEY);
    window.AUTH_TOKEN = null;
  }

  // Global auth header helper
  window.getAuthHeaders = function() {
    return {
      'Content-Type': 'application/json',
      'Authorization': 'Bearer ' + (window.AUTH_TOKEN || localStorage.getItem(TOKEN_KEY) || '')
    };
  };

  // ---- FORM TOGGLE LINKS ----

  document.addEventListener('click', function(e) {
    var target = e.target;

    // Handle link clicks by ID
    if (target.id === 'show-register' || target.closest('#show-register')) {
      e.preventDefault();
      showRegisterForm();
    }
    if (target.id === 'show-login' || target.closest('#show-login')) {
      e.preventDefault();
      showLoginForm();
    }
    if (target.id === 'show-login-2' || target.closest('#show-login-2')) {
      e.preventDefault();
      showLoginForm();
    }
    if (target.id === 'show-forgot' || target.closest('#show-forgot')) {
      e.preventDefault();
      showForgotForm();
    }

    // Logout button
    if (target.id === 'btn-logout' || target.closest('#btn-logout')) {
      e.preventDefault();
      exitApp();
      showToast('Logged out', 'info');
    }

    // Settings button
    if (target.id === 'btn-settings' || target.closest('#btn-settings')) {
      e.preventDefault();
      var modal = document.getElementById('settings-modal');
      if (modal) {
        modal.style.display = 'flex';
        modal.className = modal.className.replace('hidden', '').trim();
        load2FAStatus();
        if (typeof loadNextcloudStatus === 'function') loadNextcloudStatus();
      }
    }

    // Close settings
    if (target.id === 'close-settings' || target.closest('#close-settings')) {
      e.preventDefault();
      var modal = document.getElementById('settings-modal');
      if (modal) modal.style.display = 'none';
    }

    // Setup 2FA
    if (target.id === 'btn-setup-2fa' || target.closest('#btn-setup-2fa')) {
      e.preventDefault();
      fetch('/api/auth/setup-2fa', { method: 'POST', headers: getAuthHeaders() })
      .then(function(r) { return r.json(); })
      .then(function(data) {
        if (data.success) {
          var qr = document.getElementById('2fa-qr');
          var secret = document.getElementById('2fa-secret');
          var setup = document.getElementById('2fa-setup');
          if (qr) qr.src = data.qrCode;
          if (secret) secret.textContent = data.secret;
          if (setup) { setup.style.display = 'block'; setup.className = setup.className.replace('hidden', '').trim(); }
        }
      });
    }

    // Verify 2FA
    if (target.id === 'btn-verify-2fa' || target.closest('#btn-verify-2fa')) {
      e.preventDefault();
      var code = document.getElementById('2fa-verify-code').value;
      fetch('/api/auth/verify-2fa', {
        method: 'POST', headers: getAuthHeaders(),
        body: JSON.stringify({ code: code })
      })
      .then(function(r) { return r.json(); })
      .then(function(data) {
        if (data.success) {
          showToast('2FA enabled!', 'success');
          var setup = document.getElementById('2fa-setup');
          if (setup) setup.style.display = 'none';
          load2FAStatus();
        } else {
          showToast(data.error || 'Invalid code', 'error');
        }
      });
    }

    // Disable 2FA
    if (target.id === 'btn-disable-2fa' || target.closest('#btn-disable-2fa')) {
      e.preventDefault();
      var pw = prompt('Enter password to disable 2FA:');
      if (!pw) return;
      fetch('/api/auth/disable-2fa', {
        method: 'POST', headers: getAuthHeaders(),
        body: JSON.stringify({ password: pw })
      })
      .then(function(r) { return r.json(); })
      .then(function(data) {
        if (data.success) { showToast('2FA disabled', 'info'); load2FAStatus(); }
        else showToast(data.error || 'Failed', 'error');
      });
    }
  });

  // ---- LOGIN FORM SUBMIT ----
  if (loginForm) {
    loginForm.addEventListener('submit', function(e) {
      e.preventDefault();
      e.stopPropagation();

      var email = document.getElementById('login-email').value.trim();
      var password = document.getElementById('login-password').value;
      var totpEl = document.getElementById('login-totp');
      var totpCode = totpEl ? totpEl.value.trim() : '';

      if (!email || !password) {
        showToast('Enter email and password', 'error');
        return false;
      }

      console.log('[Auth] Attempting login for:', email);
      showLoading('Signing in...');

      var body = { email: email, password: password };
      if (totpCode) body.totpCode = totpCode;

      fetch('/api/auth/login', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(body)
      })
      .then(function(r) { return r.json(); })
      .then(function(data) {
        hideLoading();
        console.log('[Auth] Login response:', JSON.stringify(data).substring(0, 200));

        if (data.requires2FA) {
          var grp = document.getElementById('totp-group');
          if (grp) { grp.style.display = 'block'; grp.className = grp.className.replace('hidden', '').trim(); }
          showToast('Enter your 2FA code', 'info');
          return;
        }

        if (data.needsVerification) {
          showToast('Verify your email first. Check inbox.', 'error');
          return;
        }

        if (data.success && data.token && data.user) {
          enterApp(data.user, data.token);
          showToast('Welcome, ' + data.user.name + '!', 'success');
        } else {
          showToast(data.error || 'Login failed', 'error');
        }
      })
      .catch(function(err) {
        hideLoading();
        console.error('[Auth] Login error:', err);
        showToast('Connection error', 'error');
      });

      return false;
    });
  }

  // ---- REGISTER FORM SUBMIT ----
  if (registerForm) {
    registerForm.addEventListener('submit', function(e) {
      e.preventDefault();
      e.stopPropagation();

      var name = document.getElementById('reg-name').value.trim();
      var email = document.getElementById('reg-email').value.trim();
      var password = document.getElementById('reg-password').value;

      if (!name || !email || !password) {
        showToast('Fill all fields', 'error');
        return false;
      }
      if (password.length < 8) {
        showToast('Password must be 8+ characters', 'error');
        return false;
      }

      console.log('[Auth] Registering:', email);
      showLoading('Creating account...');

      fetch('/api/auth/register', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ name: name, email: email, password: password })
      })
      .then(function(r) { return r.json(); })
      .then(function(data) {
        hideLoading();
        console.log('[Auth] Register response:', JSON.stringify(data).substring(0, 200));

        if (data.success && data.token && data.user) {
          enterApp(data.user, data.token);
          showToast(data.message || 'Account created!', 'success');
        } else if (data.success && data.needsVerification) {
          showToast(data.message || 'Check email to verify', 'success');
          showLoginForm();
        } else {
          showToast(data.error || 'Registration failed', 'error');
        }
      })
      .catch(function(err) {
        hideLoading();
        console.error('[Auth] Register error:', err);
        showToast('Connection error', 'error');
      });

      return false;
    });
  }

  // ---- FORGOT PASSWORD SUBMIT ----
  if (forgotForm) {
    forgotForm.addEventListener('submit', function(e) {
      e.preventDefault();
      e.stopPropagation();

      var email = document.getElementById('forgot-email').value.trim();
      if (!email) { showToast('Enter email', 'error'); return false; }

      showLoading('Sending...');

      fetch('/api/auth/forgot-password', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ email: email })
      })
      .then(function(r) { return r.json(); })
      .then(function(data) {
        hideLoading();
        showToast(data.message || 'Check your email', 'success');
        showLoginForm();
      })
      .catch(function(err) {
        hideLoading();
        showToast('Error', 'error');
      });

      return false;
    });
  }

  // ---- 2FA STATUS ----
  function load2FAStatus() {
    fetch('/api/auth/me', { headers: getAuthHeaders() })
    .then(function(r) { return r.json(); })
    .then(function(data) {
      if (!data || !data.user) return;
      var status = document.getElementById('2fa-status');
      var setupBtn = document.getElementById('btn-setup-2fa');
      var disableBtn = document.getElementById('btn-disable-2fa');

      if (data.user.totp_enabled) {
        if (status) { status.textContent = 'Status: ✅ Enabled'; status.style.color = '#10b981'; }
        if (setupBtn) setupBtn.style.display = 'none';
        if (disableBtn) disableBtn.style.display = 'inline-flex';
      } else {
        if (status) { status.textContent = 'Status: ❌ Not enabled'; status.style.color = '#ef4444'; }
        if (setupBtn) setupBtn.style.display = 'inline-flex';
        if (disableBtn) disableBtn.style.display = 'none';
      }
    })
    .catch(function() {});
  }

  // Check registration status
  fetch('/api/auth/registration-status')
    .then(function(r) { return r.json(); })
    .then(function(data) {
      if (!data.registrationEnabled) {
        var link = document.getElementById('show-register');
        if (link) link.style.display = 'none';
      }
    })
    .catch(function() {});

  console.log('[Auth] ✅ Module ready');
});