// ===== Mobile Menu =====
const hamburger = document.getElementById('hamburger');
const mobileNav = document.getElementById('mobileNav');
const mobileNavClose = document.getElementById('mobileNavClose');
const mobileNavLinks = mobileNav.querySelectorAll('a');

hamburger.addEventListener('click', () => {
  mobileNav.classList.add('active');
  document.body.style.overflow = 'hidden';
});

mobileNavClose.addEventListener('click', closeMobileNav);

mobileNavLinks.forEach(link => {
  link.addEventListener('click', closeMobileNav);
});

function closeMobileNav() {
  mobileNav.classList.remove('active');
  document.body.style.overflow = '';
}

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

contactForm.addEventListener('submit', (e) => {
  e.preventDefault();

  // Clear previous errors
  document.querySelectorAll('.form-error').forEach(el => el.style.display = 'none');

  const name = document.getElementById('formName');
  const email = document.getElementById('formEmail');
  const phone = document.getElementById('formPhone');
  const message = document.getElementById('formMessage');

  let valid = true;

  if (!name.value.trim()) {
    showError(name, 'Prosím vyplňte své jméno');
    valid = false;
  }

  if (!email.value.trim() || !isValidEmail(email.value)) {
    showError(email, 'Prosím zadejte platný e-mail');
    valid = false;
  }

  if (!phone.value.trim()) {
    showError(phone, 'Prosím zadejte telefonní číslo');
    valid = false;
  }

  if (!message.value.trim()) {
    showError(message, 'Prosím napište zprávu');
    valid = false;
  }

  if (!valid) return;

  // Hide form, show success
  contactForm.style.display = 'none';
  formSuccess.style.display = 'block';
});

function showError(input, msg) {
  const errorEl = input.parentElement.querySelector('.form-error');
  if (errorEl) {
    errorEl.textContent = msg;
    errorEl.style.display = 'block';
  }
}

function isValidEmail(email) {
  return /^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email);
}

// ===== Plan selection from pricing buttons =====
const formPlan = document.getElementById('formPlan');

document.querySelectorAll('.plan-btn').forEach(btn => {
  btn.addEventListener('click', (e) => {
    e.preventDefault();
    const plan = btn.getAttribute('data-plan');
    if (formPlan && plan) {
      formPlan.value = plan;
      formPlan.parentElement.classList.add('highlight-field');
      setTimeout(() => formPlan.parentElement.classList.remove('highlight-field'), 1500);
    }
    document.getElementById('kontakt').scrollIntoView({ behavior: 'smooth' });
  });
});

// ===== Smooth Scroll for anchor links =====
document.querySelectorAll('a[href^="#"]').forEach(anchor => {
  if (anchor.classList.contains('plan-btn')) return;
  anchor.addEventListener('click', (e) => {
    const target = document.querySelector(anchor.getAttribute('href'));
    if (target) {
      e.preventDefault();
      target.scrollIntoView({ behavior: 'smooth' });
    }
  });
});

// ===== Header shadow on scroll =====
const header = document.querySelector('.header');
window.addEventListener('scroll', () => {
  if (window.scrollY > 10) {
    header.style.boxShadow = '0 2px 12px rgba(0,0,0,.08)';
  } else {
    header.style.boxShadow = 'none';
  }
}, { passive: true });

// ===== Close mobile nav on resize past breakpoint =====
window.addEventListener('resize', () => {
  if (window.innerWidth > 960 && mobileNav.classList.contains('active')) {
    closeMobileNav();
  }
});