document.addEventListener('DOMContentLoaded', () => {
  const createForm = document.getElementById('create-form');
  const statusFilter = document.getElementById('status-filter');
  const categoryFilter = document.getElementById('category-filter');
  const searchInput = document.getElementById('search-input');

  const openModalBtn = document.getElementById('open-modal-btn');
  const modal = document.getElementById('create-ticket-modal');
  const closeModalBtn = document.getElementById('close-modal-btn');

  const updatePfpBtn = document.getElementById('update-pfp-btn');
  const pfpModal = document.getElementById('update-pfp-modal');
  const dropZone = document.getElementById('drop-zone');
  const fileInput = document.getElementById('pfp-file-input');
  const uploadPfpBtn = document.getElementById('upload-pfp-btn');

  // Accordion elements
  const closedToggle = document.getElementById('closed-toggle');
  const closedAccordion = document.getElementById('closed-accordion');
  const closedCount = document.getElementById('closed-count');

  let selectedPfpFile = null;
  let allTickets = [];
  let accordionOpen = false;

  // --- XSS Protection ---
  function escapeHtml(str) {
    if (!str) return '';
    const div = document.createElement('div');
    div.textContent = str;
    return div.innerHTML;
  }

  function formatStatusClass(status) {
    if (!status) return 'Unknown';
    return status.split(' ').map(s => s.charAt(0).toUpperCase() + s.slice(1).toLowerCase()).join('-');
  }

  // --- Dynamic Categories ---
  async function loadCategories() {
    try {
      const res = await fetch('/api/categories');
      const categories = await res.json();
      populateCategorySelects(categories);
    } catch (err) {
      console.error('Failed to load categories:', err);
    }
  }

  function populateCategorySelects(categories) {
    // Modal create form select
    const createSelect = document.getElementById('category');
    if (createSelect) {
      createSelect.innerHTML = categories.map(c => `<option value="${escapeHtml(c)}">${escapeHtml(c)}</option>`).join('');
    }
    // Filter select (keep "All Categories" as first option)
    if (categoryFilter) {
      categoryFilter.innerHTML = '<option value="all">All Categories</option>' +
        categories.map(c => `<option value="${escapeHtml(c)}">${escapeHtml(c)}</option>`).join('');
    }
  }

  // --- Accordion ---
  if (closedToggle) {
    closedToggle.addEventListener('click', () => {
      accordionOpen = !accordionOpen;
      closedAccordion.style.display = accordionOpen ? 'block' : 'none';
      closedToggle.classList.toggle('open', accordionOpen);
    });
  }

  // --- Ticket Modal ---
  function openModal() {
    if (modal) {
      const scrollBarWidth = window.innerWidth - document.documentElement.clientWidth;
      modal.style.display = 'flex';
      document.body.style.overflow = 'hidden';
      document.documentElement.style.overflow = 'hidden';
      if (scrollBarWidth > 0) document.body.style.paddingRight = scrollBarWidth + 'px';
    }
  }
  function closeModal() {
    if (modal) {
      modal.style.display = 'none';
      document.body.style.overflow = '';
      document.documentElement.style.overflow = '';
      document.body.style.paddingRight = '';
    }
  }
  if (openModalBtn) openModalBtn.addEventListener('click', openModal);
  if (closeModalBtn) closeModalBtn.addEventListener('click', closeModal);
  if (modal) {
    window.addEventListener('click', (e) => { if (e.target === modal) closeModal(); });
    window.addEventListener('keydown', (e) => { if (e.key === 'Escape' && modal.style.display === 'flex') closeModal(); });
  }

  // --- PFP Modal ---
  function openPfpModal() {
    if (pfpModal) {
      const scrollBarWidth = window.innerWidth - document.documentElement.clientWidth;
      pfpModal.style.display = 'flex';
      document.body.style.overflow = 'hidden';
      document.documentElement.style.overflow = 'hidden';
      if (scrollBarWidth > 0) document.body.style.paddingRight = scrollBarWidth + 'px';
    }
  }
  function closePfpModal() {
    if (pfpModal) {
      pfpModal.style.display = 'none';
      document.body.style.overflow = '';
      document.documentElement.style.overflow = '';
      document.body.style.paddingRight = '';
    }
  }
  if (updatePfpBtn) updatePfpBtn.addEventListener('click', openPfpModal);
  if (pfpModal) {
    window.addEventListener('click', (e) => { if (e.target === pfpModal) closePfpModal(); });
    window.addEventListener('keydown', (e) => { if (e.key === 'Escape' && pfpModal.style.display === 'flex') closePfpModal(); });
  }

  // --- Drag & Drop ---
  if (dropZone) {
    dropZone.addEventListener('click', () => fileInput.click());
    dropZone.addEventListener('dragover', (e) => { e.preventDefault(); dropZone.style.borderColor = '#10b981'; });
    dropZone.addEventListener('dragleave', () => { dropZone.style.borderColor = '#4b5563'; });
    dropZone.addEventListener('drop', (e) => {
      e.preventDefault();
      dropZone.style.borderColor = '#4b5563';
      const file = e.dataTransfer.files[0];
      if (file && file.type.startsWith('image/')) {
        selectedPfpFile = file;
        dropZone.querySelector('p').textContent = file.name;
      }
    });
  }
  if (fileInput) {
    fileInput.addEventListener('change', (e) => {
      const file = e.target.files[0];
      if (file && file.type.startsWith('image/')) {
        selectedPfpFile = file;
        dropZone.querySelector('p').textContent = file.name;
      }
    });
  }
  if (uploadPfpBtn) {
    uploadPfpBtn.addEventListener('click', async () => {
      if (!selectedPfpFile) return alert('Please select an image first.');
      const formData = new FormData();
      formData.append('pfp', selectedPfpFile, 'user.jpg');
      try {
        const res = await fetch('/api/upload-pfp', { method: 'POST', body: formData });
        if (!res.ok) throw new Error('Upload failed');
        alert('Profile picture updated!');
        closePfpModal();
        window.location.reload();
      } catch (err) {
        console.error(err);
        alert('Error uploading profile picture');
      }
    });
  }

  // --- API ---
  async function fetchTickets() {
    try {
      const res = await fetch('/api/tickets');
      return await res.json();
    } catch (err) {
      console.error('Error fetching tickets:', err);
      return [];
    }
  }
  async function createTicket(ticket) {
    const res = await fetch('/api/tickets', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify(ticket),
    });
    if (!res.ok) throw new Error('Failed to create ticket');
    return await res.json();
  }

  function formatDate(dateStr) {
    return new Date(dateStr).toLocaleDateString(undefined, {
      year: 'numeric', month: 'short', day: 'numeric',
    });
  }

  // --- Render ---
  function renderFilteredTickets() {
    const status = statusFilter?.value || 'all';
    const category = categoryFilter?.value || 'all';
    const search = searchInput?.value.trim().toLowerCase() || '';

    const filtered = allTickets.filter(ticket => {
      const ticketStatus = (ticket.status || '').toLowerCase();
      const ticketCategory = (ticket.category || '').toLowerCase();
      const ticketTitle = (ticket.title || '').toLowerCase();
      const ticketDescription = (ticket.description || '').toLowerCase();
      const isClosed = ticketStatus === 'closed';
      const matchesStatus = status === 'all' || ticketStatus === status.toLowerCase();
      const matchesCategory = category === 'all' || ticketCategory === category.toLowerCase();
      const matchesSearch = ticketTitle.includes(search) || ticketDescription.includes(search);
      return (isClosed || matchesStatus) && matchesCategory && matchesSearch;
    });

    renderTickets(filtered);
  }

  function renderTickets(tickets) {
    const openContainer = document.getElementById('tickets-container');
    const closedContainer = document.getElementById('closed-tickets-container');
    openContainer.innerHTML = '';
    closedContainer.innerHTML = '';

    let closedTicketCount = 0;

    if (!tickets.length) {
      openContainer.innerHTML = `
        <div class="empty-state">
          <i class="fas fa-inbox"></i>
          <h3>No tickets found</h3>
          <p>Try changing your filters or create a new ticket</p>
        </div>`;
      if (closedCount) closedCount.textContent = '0';
      return;
    }

    tickets.sort((a, b) => new Date(b.created_at) - new Date(a.created_at));

    tickets.forEach(ticket => {
      const statusSafe = formatStatusClass(ticket.status);
      const prioritySafe = ticket.priority || 'None';
      const el = document.createElement('div');
      el.className = `ticket status-${statusSafe.replace(/\s+/g, '-')}`;
      el.innerHTML = `
        <h3>${escapeHtml(ticket.title)} <span class="ticket-id">#${ticket.id}</span></h3>
        <p class="description">${escapeHtml(ticket.description)}</p>
        <div class="meta">
          <span class="date"><i class="fas fa-calendar"></i> ${formatDate(ticket.created_at)}</span>
          <span class="total-time"><i class="fas fa-clock"></i> ${ticket.total_time} min</span>
        </div>
        <div class="status-row">
          <div class="status status-${statusSafe.replace(/\s+/g, '-')}">
            <i class="fas fa-circle"></i> ${escapeHtml(ticket.status)}
          </div>
          ${ticket.category ? `<div class="category-badge"><i class="fas fa-tag"></i> ${escapeHtml(ticket.category)}</div>` : ''}
          <div class="priority priority-${prioritySafe.replace(/\s+/g, '-')}">
            <i class="fas fa-flag"></i> ${escapeHtml(prioritySafe)}
          </div>
        </div>
        <div class="ticket-actions">
          <a href="/ticketview/ticket-view-user.html?id=${ticket.id}" class="action-btn view-btn">
            <i class="fas fa-eye"></i> View Details
          </a>
        </div>
      `;
      if ((ticket.status || '').toLowerCase() === 'closed') {
        closedContainer.appendChild(el);
        closedTicketCount++;
      } else {
        openContainer.appendChild(el);
      }
    });

    if (closedCount) closedCount.textContent = closedTicketCount;
  }

  // --- Handlers ---
  let isSubmittingTicket = false;

  async function handleCreateTicket(e) {
    e.preventDefault();
    if (isSubmittingTicket) return;
    isSubmittingTicket = true;

    const title = document.getElementById('title')?.value.trim();
    const description = document.getElementById('description')?.value.trim();
    const priority = document.getElementById('priority')?.value;
    const category = document.getElementById('category')?.value;

    if (!title || !description) {
      alert('Please fill in all required fields');
      isSubmittingTicket = false;
      return;
    }

    const submitBtn = createForm.querySelector('.btn-primary');
    submitBtn.disabled = true;

    try {
      await createTicket({ title, description, priority, category, requester: 'Laila', status: 'Open' });
      createForm.reset();
      closeModal();
      await refreshTickets();

      submitBtn.innerHTML = '<i class="fas fa-check"></i> Created!';
      submitBtn.style.backgroundColor = '#28a745';
      setTimeout(() => {
        submitBtn.innerHTML = '<i class="fas fa-paper-plane"></i> Create Ticket';
        submitBtn.style.backgroundColor = '';
        submitBtn.disabled = false;
        isSubmittingTicket = false;
      }, 2000);
    } catch {
      alert('Failed to create ticket');
      submitBtn.disabled = false;
      isSubmittingTicket = false;
    }
  }

  async function refreshTickets() {
    allTickets = await fetchTickets();
    renderFilteredTickets();
  }

  // --- Init ---
  if (createForm) createForm.addEventListener('submit', handleCreateTicket);
  if (statusFilter) statusFilter.addEventListener('change', renderFilteredTickets);
  if (categoryFilter) categoryFilter.addEventListener('change', renderFilteredTickets);
  if (searchInput) searchInput.addEventListener('input', renderFilteredTickets);

  loadCategories().then(() => refreshTickets());
});