// Theme toggle
const themeToggle = document.getElementById('themeToggle');
const themeIcon = document.getElementById('themeIcon');

function applyTheme(theme) {
    document.documentElement.setAttribute('data-bs-theme', theme);
    themeIcon.className = theme === 'dark' ? 'bi bi-sun-fill' : 'bi bi-moon-fill';
    localStorage.setItem('theme', theme);
}

applyTheme(localStorage.getItem('theme') || 'dark');

themeToggle.addEventListener('click', () => {
    const current = document.documentElement.getAttribute('data-bs-theme');
    applyTheme(current === 'dark' ? 'light' : 'dark');
});

// View switching
const views = {
    login: document.getElementById('loginView'),
    register: document.getElementById('registerView'),
    forgot: document.getElementById('forgotView'),
    setPassword: document.getElementById('setPasswordView'),
};

function showView(name) {
    Object.values(views).forEach(v => v.classList.add('d-none'));
    views[name].classList.remove('d-none');
}

document.getElementById('showRegister').addEventListener('click', (e) => { e.preventDefault(); showView('register'); });
document.getElementById('showLoginFromReg').addEventListener('click', (e) => { e.preventDefault(); showView('login'); });
document.getElementById('showForgot').addEventListener('click', (e) => { e.preventDefault(); showView('forgot'); });
document.getElementById('showLoginFromForgot').addEventListener('click', (e) => { e.preventDefault(); showView('login'); });

// Check URL for token (verify or reset-password)
const urlParams = new URLSearchParams(window.location.search);
const token = urlParams.get('token');
const isVerify = window.location.pathname === '/auth/verify';
const isReset = window.location.pathname === '/auth/reset-password';

if (token && (isVerify || isReset)) {
    showView('setPassword');
    document.getElementById('setPasswordTitle').textContent = isVerify ? 'Passwort setzen' : 'Passwort zuruecksetzen';
}

// Show register view if on /register
if (window.location.pathname === '/register') {
    showView('register');
}

function showAlert(id, message, type) {
    const el = document.getElementById(id);
    el.className = `alert alert-${type} py-1 small`;
    el.textContent = message;
}

// Login
document.getElementById('btnLogin').addEventListener('click', async () => {
    const email = document.getElementById('loginEmail').value.trim();
    const password = document.getElementById('loginPassword').value;
    if (!email || !password) return;

    try {
        const resp = await fetch('/auth/login', {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({ email, password })
        });
        const data = await resp.json();
        if (resp.ok) {
            window.location.href = '/';
        } else {
            showAlert('loginAlert', data.error || 'Anmeldung fehlgeschlagen', 'danger');
        }
    } catch (e) {
        showAlert('loginAlert', 'Verbindungsfehler', 'danger');
    }
});

document.getElementById('loginPassword').addEventListener('keydown', (e) => {
    if (e.key === 'Enter') document.getElementById('btnLogin').click();
});

// Register
document.getElementById('btnRegister').addEventListener('click', async () => {
    const name = document.getElementById('registerName').value.trim();
    const email = document.getElementById('registerEmail').value.trim();
    if (!name || !email) return;

    try {
        const resp = await fetch('/auth/register', {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({ name, email })
        });
        const data = await resp.json();
        if (resp.ok) {
            showAlert('registerAlert', data.message || 'Registrierung erfolgreich', 'success');
        } else {
            showAlert('registerAlert', data.error || 'Registrierung fehlgeschlagen', 'danger');
        }
    } catch (e) {
        showAlert('registerAlert', 'Verbindungsfehler', 'danger');
    }
});

// Forgot password
document.getElementById('btnForgot').addEventListener('click', async () => {
    const email = document.getElementById('forgotEmail').value.trim();
    if (!email) return;

    try {
        const resp = await fetch('/auth/forgot-password', {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({ email })
        });
        const data = await resp.json();
        showAlert('forgotAlert', data.message || 'Link gesendet', 'success');
    } catch (e) {
        showAlert('forgotAlert', 'Verbindungsfehler', 'danger');
    }
});

// Set password (verify + reset)
document.getElementById('btnSetPassword').addEventListener('click', async () => {
    const password = document.getElementById('newPassword').value;
    const confirm = document.getElementById('confirmPassword').value;

    if (password.length < 8) {
        showAlert('setPasswordAlert', 'Passwort muss mindestens 8 Zeichen lang sein', 'danger');
        return;
    }
    if (password !== confirm) {
        showAlert('setPasswordAlert', 'Passwoerter stimmen nicht ueberein', 'danger');
        return;
    }

    const endpoint = isReset ? '/auth/reset-password' : '/auth/set-password';

    try {
        const resp = await fetch(endpoint, {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({ token, password })
        });
        const data = await resp.json();
        if (resp.ok) {
            showAlert('setPasswordAlert', data.message || 'Passwort gespeichert', 'success');
            setTimeout(() => { window.location.href = '/login'; }, 2000);
        } else {
            showAlert('setPasswordAlert', data.error || 'Fehler', 'danger');
        }
    } catch (e) {
        showAlert('setPasswordAlert', 'Verbindungsfehler', 'danger');
    }
});