document.addEventListener('DOMContentLoaded', () => {
    // Navbar Scroll Effect
    const navbar = document.querySelector('.navbar');
    window.addEventListener('scroll', () => {
        if (navbar) {
            if (window.scrollY > 50) {
                navbar.classList.add('scrolled');
            } else {
                navbar.classList.remove('scrolled');
            }
        }
    });

    // Mobile Menu Toggle
    const mobileMenuToggle = document.querySelector('.mobile-menu-toggle');
    const navLinks = document.querySelector('.nav-links');
    
    if (mobileMenuToggle) {
        mobileMenuToggle.addEventListener('click', () => {
            navLinks.classList.toggle('active');
            const icon = mobileMenuToggle.querySelector('i');
            if (navLinks.classList.contains('active')) {
                icon.classList.replace('fa-bars', 'fa-times');
            } else {
                icon.classList.replace('fa-times', 'fa-bars');
            }
        });
    }

    // Hero Swiper
    const heroSwiper = new Swiper('.hero-swiper', {
        loop: true,
        effect: 'fade',
        fadeEffect: {
            crossFade: true
        },
        autoplay: {
            delay: 6000,
            disableOnInteraction: false,
        }
    });

    // Portfolio Filtering
    const filterBtns = document.querySelectorAll('.filter-btn');
    const portfolioItems = document.querySelectorAll('.portfolio-item');

    filterBtns.forEach(btn => {
        btn.addEventListener('click', () => {
            filterBtns.forEach(b => b.classList.remove('active'));
            btn.classList.add('active');

            const filterValue = btn.getAttribute('data-filter');

            portfolioItems.forEach(item => {
                if (filterValue === 'all' || item.classList.contains(filterValue)) {
                    item.style.display = 'block';
                    item.style.animation = 'fadeIn 0.5s ease forwards';
                } else {
                    item.style.display = 'none';
                }
            });
        });
    });

    // Contact Form Submission
    const contactForm = document.getElementById('contactForm');
    const toast = document.getElementById('toast');

    // Simple I18N for JS messages based on html lang attribute
    const htmlLang = document.documentElement.lang || 'en';
    const messages = {
        en: { sending: 'Sending...', success: 'Message sent successfully!', error: 'Failed to send. Please try again.' },
        zh: { sending: '发送中...', success: '消息已成功发送！', error: '发送失败，请稍后再试。' },
        ja: { sending: '送信中...', success: '送信が完了しました！', error: '送信に失敗しました。' },
        ko: { sending: '전송 중...', success: '메시지가 성공적으로 전송되었습니다!', error: '전송 실패. 다시 시도하십시오.' },
        de: { sending: 'Senden...', success: 'Nachricht erfolgreich gesendet!', error: 'Fehler beim Senden.' },
        fr: { sending: 'Envoi...', success: 'Message envoyé avec succès !', error: 'Échec de l\'envoi.' },
        es: { sending: 'Enviando...', success: '¡Mensaje enviado con éxito!', error: 'Error al enviar.' },
        ar: { sending: 'جاري الإرسال...', success: 'تم إرسال الرسالة بنجاح!', error: 'فشل الإرسال. يرجى المحاولة مرة أخرى.' }
    };
    const msg = messages[htmlLang] || messages['en'];

    if (contactForm) {
        contactForm.addEventListener('submit', async (e) => {
            e.preventDefault();
            
            const formData = new FormData(contactForm);
            const submitBtn = contactForm.querySelector('.btn-submit');
            const originalBtnContent = submitBtn.innerHTML;
            
            submitBtn.disabled = true;
            submitBtn.innerHTML = `<span>${msg.sending}</span> <i class="fas fa-spinner fa-spin"></i>`;

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

                const result = await response.json();

                if (result.success) {
                    showToast(msg.success);
                    contactForm.reset();
                } else {
                    showToast(msg.error + ' ' + (result.error || ''));
                }
            } catch (error) {
                showToast(msg.error);
            } finally {
                submitBtn.disabled = false;
                submitBtn.innerHTML = originalBtnContent;
            }
        });
    }

    function showToast(message) {
        if (!toast) return;
        toast.innerText = message;
        toast.style.display = 'block';
        toast.style.animation = 'slideInUp 0.5s ease forwards';
        
        setTimeout(() => {
            toast.style.animation = 'slideOutDown 0.5s ease forwards';
            setTimeout(() => {
                toast.style.display = 'none';
            }, 500);
        }, 5000);
    }

    // Smooth scroll for nav links
    document.querySelectorAll('a[href^="#"]').forEach(anchor => {
        anchor.addEventListener('click', function (e) {
            if (this.hash !== "") {
                e.preventDefault();
                const target = document.querySelector(this.hash);
                if (target) {
                    if (navLinks && navLinks.classList.contains('active')) {
                        navLinks.classList.remove('active');
                        const icon = mobileMenuToggle.querySelector('i');
                        icon.classList.replace('fa-times', 'fa-bars');
                    }
                    window.scrollTo({
                        top: target.offsetTop - 80,
                        behavior: 'smooth'
                    });
                }
            }
        });
    });
});

const animStyle = document.createElement('style');
animStyle.textContent = "
    @keyframes fadeIn {
        from { opacity: 0; transform: translateY(20px); } 
        to { opacity: 1; transform: translateY(0); }
    }
    @keyframes slideInUp {
        from { transform: translateY(100%); opacity: 0; } 
        to { transform: translateY(0); opacity: 1; }
    }
    @keyframes slideOutDown {
        from { transform: translateY(0); opacity: 1; } 
        to { transform: translateY(100%); opacity: 0; }
    }
";
document.head.appendChild(animStyle);