// login.js

document.addEventListener("DOMContentLoaded", function() {
    const loginForm = document.getElementById('loginForm');
    const loginBtn = document.getElementById('loginSubmit');
    const successMessage = document.getElementById('successMessage');
    const errorMessage = document.getElementById('errorMessage');
    const errorText = document.getElementById('errorText');
    const registerBtn = document.getElementById('registerBtn');

    // Register button functionality
    if (registerBtn) {
        registerBtn.addEventListener('click', function(e) {
            e.preventDefault();
            window.location.href = 'register.html';
        });
    }

    // Check if user is already logged in
    checkExistingSession();

    // Login form submission
    if (loginForm) {
        loginForm.addEventListener('submit', async function(e) {
            e.preventDefault();
            
            const email = document.getElementById('email').value;
            const password = document.getElementById('password').value;
            const remember = document.getElementById('remember').checked;
            
            // Simple validation
            if (!email || !password) {
                showError('Bitte füllen Sie alle Felder aus.');
                return;
            }
            
            // Email validation
            const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
            if (!emailRegex.test(email)) {
                showError('Bitte geben Sie eine gültige E-Mail-Adresse ein.');
                return;
            }
            
            // Show loading state
            setLoadingState(true);
            hideMessages();
            
            // Send login data to PHP API
            const loginData = {
                type: 'login',
                email: email,
                password: password,
                remember: remember
            };
            
            try {
                const response = await fetch('../scripts/add/send.php', {
                    method: 'POST',
                    headers: {
                        'Content-Type': 'application/json',
                    },
                    body: JSON.stringify(loginData)
                });

                const result = await response.json();
                
                if (result.success) {
                    // Store session (for demo purposes - in real app, this would come from server)
                    const sessionData = {
                        user: { email: email },
                        loginTime: new Date().toISOString(),
                        remember: remember
                    };
                    
                    if (remember) {
                        localStorage.setItem('userSession', JSON.stringify(sessionData));
                    } else {
                        sessionStorage.setItem('userSession', JSON.stringify(sessionData));
                    }
                    
                    // Show success message
                    showSuccess('Anmeldung erfolgreich! Sie werden weitergeleitet...');
                    
                    // Redirect after delay
                    setTimeout(() => {
                        window.location.href = '../index.html';
                    }, 2000);
                } else {
                    showError('Anmeldung fehlgeschlagen: ' + result.message);
                }
            } catch (error) {
                console.error('Login error:', error);
                showError('Netzwerkfehler bei der Anmeldung. Bitte versuchen Sie es später erneut.');
            }
            
            setLoadingState(false);
        });
    }

    // Loading state management
    function setLoadingState(loading) {
        if (loginBtn) {
            const btnText = loginBtn.querySelector('.btn-text');
            const btnLoading = loginBtn.querySelector('.btn-loading');
            
            if (loading) {
                loginBtn.disabled = true;
                if (btnText) btnText.style.display = 'none';
                if (btnLoading) btnLoading.style.display = 'inline-block';
            } else {
                loginBtn.disabled = false;
                if (btnText) btnText.style.display = 'inline-block';
                if (btnLoading) btnLoading.style.display = 'none';
            }
        }
    }

    // Message display functions
    function showSuccess(message) {
        if (successMessage) {
            const messageElement = successMessage.querySelector('p');
            if (messageElement) {
                messageElement.textContent = message;
            }
            successMessage.classList.add('show');
        }
    }

    function showError(message) {
        if (errorMessage && errorText) {
            errorText.textContent = message;
            errorMessage.classList.add('show');
            
            // Hide after 5 seconds
            setTimeout(() => {
                errorMessage.classList.remove('show');
            }, 5000);
        }
    }

    function hideMessages() {
        if (successMessage) successMessage.classList.remove('show');
        if (errorMessage) errorMessage.classList.remove('show');
    }
});

// Check existing session - DISABLED auto-redirect
function checkExistingSession() {
    const sessionData = localStorage.getItem('userSession') || sessionStorage.getItem('userSession');
    
    if (sessionData) {
        try {
            const session = JSON.parse(sessionData);
            const loginTime = new Date(session.loginTime);
            const now = new Date();
            const sessionAge = (now - loginTime) / (1000 * 60 * 60); // hours
            
            // Auto-logout after 24 hours
            if (sessionAge < 24) {
                // User is still logged in - just log it, don't redirect
                console.log('User already logged in');
                // DISABLED: window.location.href = '../index.html';
            } else {
                // Session expired, remove it
                console.log('Session expired, removing...');
                localStorage.removeItem('userSession');
                sessionStorage.removeItem('userSession');
            }
        } catch (error) {
            console.error('Session parsing error:', error);
            localStorage.removeItem('userSession');
            sessionStorage.removeItem('userSession');
        }
    }
}

// Logout function (can be called from other pages)
function logout() {
    localStorage.removeItem('userSession');
    sessionStorage.removeItem('userSession');
    window.location.href = 'sites/login.html';
}

// Get current user (can be called from other pages)
function getCurrentUser() {
    const sessionData = localStorage.getItem('userSession') || sessionStorage.getItem('userSession');
    
    if (sessionData) {
        try {
            const session = JSON.parse(sessionData);
            const loginTime = new Date(session.loginTime);
            const now = new Date();
            const sessionAge = (now - loginTime) / (1000 * 60 * 60); // hours
            
            if (sessionAge < 24) {
                return session.user;
            } else {
                // Session expired
                localStorage.removeItem('userSession');
                sessionStorage.removeItem('userSession');
                return null;
            }
        } catch (error) {
            console.error('Session parsing error:', error);
            localStorage.removeItem('userSession');
            sessionStorage.removeItem('userSession');
            return null;
        }
    }
    
    return null;
}

// Check if user is logged in (can be called from other pages)
function isLoggedIn() {
    return getCurrentUser() !== null;
}