document.addEventListener('DOMContentLoaded', () => {

    // === Mobile nav toggle ===
    const navToggle = document.getElementById('nav-toggle');
    const nav = document.getElementById('nav');

    if (navToggle && nav) {
        navToggle.addEventListener('click', () => {
            nav.classList.toggle('open');
            navToggle.classList.toggle('open');
        });

        // Close nav on link click
        nav.querySelectorAll('a').forEach(link => {
            link.addEventListener('click', () => {
                nav.classList.remove('open');
                navToggle.classList.remove('open');
            });
        });
    }

    // === Sticky header ===
    const header = document.getElementById('header');
    if (header) {
        window.addEventListener('scroll', () => {
            header.classList.toggle('scrolled', window.scrollY > 50);
        }, { passive: true });
    }

    // === Scroll animations ===
    const observerOptions = {
        threshold: 0.1,
        rootMargin: '0px 0px -50px 0px'
    };

    const observer = new IntersectionObserver((entries) => {
        entries.forEach(entry => {
            if (entry.isIntersecting) {
                entry.target.classList.add('visible');
                observer.unobserve(entry.target);
            }
        });
    }, observerOptions);

    // Add fade-in to sections
    document.querySelectorAll('.service-card, .feature, .pricing-card, .faq-item, .contact-form, .contact-info').forEach(el => {
        el.classList.add('fade-in');
        observer.observe(el);
    });

    // === FAQ toggle ===
    document.querySelectorAll('.faq-question').forEach(btn => {
        btn.addEventListener('click', () => {
            const expanded = btn.getAttribute('aria-expanded') === 'true';
            btn.setAttribute('aria-expanded', !expanded);
            btn.nextElementSibling.classList.toggle('open');
        });
    });

    // === Contact form ===
    const form = document.getElementById('contact-form');
    const formStatus = document.getElementById('form-status');

    if (form) {
        form.addEventListener('submit', async (e) => {
            e.preventDefault();

            const submitBtn = form.querySelector('.btn-submit');
            const originalText = submitBtn.textContent;
            submitBtn.textContent = 'Lähetetään...';
            submitBtn.disabled = true;

            // Honeypot check
            const honeypot = form.querySelector('input[name="website"]');
            if (honeypot && honeypot.value) {
                formStatus.textContent = 'Kiitos viestistäsi!';
                formStatus.className = 'form-status success';
                form.reset();
                submitBtn.textContent = originalText;
                submitBtn.disabled = false;
                return;
            }

            const formData = new FormData(form);

            try {
                const response = await fetch('api.php?action=contact', {
                    method: 'POST',
                    body: formData
                });

                const data = await response.json();

                if (data.success) {
                    formStatus.textContent = 'Kiitos viestistäsi! Otamme yhteyttä pian.';
                    formStatus.className = 'form-status success';
                    form.reset();
                } else {
                    formStatus.textContent = data.error || 'Viestin lähetys epäonnistui. Yritä uudelleen.';
                    formStatus.className = 'form-status error';
                }
            } catch {
                formStatus.textContent = 'Viestin lähetys epäonnistui. Yritä uudelleen.';
                formStatus.className = 'form-status error';
            }

            submitBtn.textContent = originalText;
            submitBtn.disabled = false;
        });
    }

    // === Active nav link on scroll ===
    const sections = document.querySelectorAll('section[id]');
    const navLinks = document.querySelectorAll('.nav a[href^="#"]');

    if (sections.length && navLinks.length) {
        window.addEventListener('scroll', () => {
            let current = '';
            sections.forEach(section => {
                const top = section.offsetTop - 100;
                if (window.scrollY >= top) {
                    current = section.getAttribute('id');
                }
            });

            navLinks.forEach(link => {
                link.classList.remove('active');
                if (link.getAttribute('href') === '#' + current) {
                    link.classList.add('active');
                }
            });
        }, { passive: true });
    }

});