document.addEventListener('DOMContentLoaded', () => {
  const ticketsBody = document.getElementById('tickets-body');
  const closedTicketsBody = document.getElementById('closed-tickets-body');
  const searchInput = document.getElementById('search-tickets');
  const statusFilter = document.getElementById('status-filter');
  const priorityFilter = document.getElementById('priority-filter');
  const categoryFilter = document.getElementById('category-filter');
  const statTotal = document.getElementById('total-tickets');
  const statOpen = document.getElementById('open-tickets');
  const statInProgress = document.getElementById('in-progress-tickets');
  const statClosed = document.getElementById('closed-tickets');
  const statTotalTime = document.getElementById('time-tickets');

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

  // PFP elements
  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');

  let selectedPfpFile = null;
  let accordionOpen = false;

  searchInput.addEventListener('input', refreshTickets);
  statusFilter.addEventListener('change', refreshTickets);
  priorityFilter.addEventListener('change', refreshTickets);
  categoryFilter.addEventListener('change', refreshTickets);

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

  function toTitleCaseWithDash(str) {
    return str.split(' ').map(word => word.charAt(0).toUpperCase() + word.slice(1).toLowerCase()).join('-');
  }

  // --- Dynamic Categories ---
  async function loadCategories() {
    try {
      const res = await fetch('/api/categories');
      const categories = await res.json();
      if (categoryFilter) {
        categoryFilter.innerHTML = '<option value="all">All Categories</option>' +
          categories.map(c => `<option value="${escapeHtml(c)}">${escapeHtml(c)}</option>`).join('');
      }
    } catch (err) {
      console.error('Failed to load categories:', err);
    }
  }

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

  // --- 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, 'admin.jpg');
      try {
        const res = await fetch('/api/upload-admin-pfp', { method: 'POST', body: formData });
        if (!res.ok) throw new Error('Upload failed');
        alert('Admin 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 deleteTicket(id) {
    try {
      const res = await fetch(`/api/tickets/${id}`, {
        method: 'DELETE',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ actor: 'Admin' }),
      });
      return await res.json();
    } catch (err) {
      console.error('Error deleting ticket:', err);
    }
  }

  async function refreshTickets() {
    const tickets = await fetchTickets();
    renderTickets(tickets);
    updateStats(tickets);
  }

  function renderTickets(tickets) {
    const status = statusFilter.value;
    const priority = priorityFilter.value;
    const category = categoryFilter.value;
    const searchTerm = searchInput.value.toLowerCase();

    const filtered = tickets
      .filter(t =>
        (status === 'all' || t.status === status) &&
        (priority === 'all' || t.priority === priority) &&
        (category === 'all' || t.category === category) &&
        (t.title.toLowerCase().includes(searchTerm) ||
          t.description.toLowerCase().includes(searchTerm) ||
          t.requester.toLowerCase().includes(searchTerm))
      )
      .sort((a, b) => new Date(b.created_at) - new Date(a.created_at));

    const openRows = [];
    const closedRows = [];

    filtered.forEach(ticket => {
      const shortTitle = ticket.title.length > 50 ? ticket.title.slice(0, 50) + '...' : ticket.title;
      const statusClass = toTitleCaseWithDash(ticket.status || 'Unknown');
      const priorityClass = toTitleCaseWithDash(ticket.priority || 'None');

      const rowHTML = `
        <tr>
          <td>${ticket.id}</td>
          <td class="ticket-title">${escapeHtml(shortTitle)}</td>
          <td>${escapeHtml(ticket.requester)}</td>
          <td>${escapeHtml(ticket.category) || '-'}</td>
          <td><span class="status-badge status-${statusClass}">${escapeHtml(ticket.status) || 'Unknown'}</span></td>
          <td><span class="priority-badge priority-${priorityClass}">${escapeHtml(ticket.priority) || 'None'}</span></td>
          <td>${formatDate(ticket.created_at)}</td>
          <td>${ticket.total_time} min</td>
          <td class="table-actions">
            <button class="table-btn view-btn" data-id="${ticket.id}"><i class="fas fa-eye"></i></button>
            <button class="table-btn delete-btn" data-id="${ticket.id}"><i class="fas fa-trash-alt"></i></button>
          </td>
        </tr>`;

      if (ticket.status === 'Closed') closedRows.push(rowHTML);
      else openRows.push(rowHTML);
    });

    ticketsBody.innerHTML = openRows.length
      ? openRows.join('')
      : `<tr><td colspan="9" class="empty-table">No open tickets found</td></tr>`;

    if (closedTicketsBody) {
      closedTicketsBody.innerHTML = closedRows.length
        ? closedRows.join('')
        : `<tr><td colspan="9" class="empty-table">No closed tickets</td></tr>`;
    }

    if (closedCount) closedCount.textContent = closedRows.length;

    document.querySelectorAll('.view-btn').forEach(btn =>
      btn.addEventListener('click', () => {
        window.location.href = `/ticketview/ticket-view-admin.html?id=${btn.dataset.id}`;
      })
    );
    document.querySelectorAll('.delete-btn').forEach(btn =>
      btn.addEventListener('click', () => {
        if (confirm('Are you sure you want to delete this ticket?')) {
          deleteTicket(btn.dataset.id).then(refreshTickets);
        }
      })
    );
  }

  function updateStats(tickets) {
    statTotal.textContent = tickets.length;
    statOpen.textContent = tickets.filter(t => t.status === 'Open').length;
    statInProgress.textContent = tickets.filter(t => t.status === 'In Progress').length;
    statClosed.textContent = tickets.filter(t => t.status === 'Closed').length;
    const totalTime = tickets.reduce((sum, t) => sum + (t.total_time || 0), 0);
    statTotalTime.textContent = `${totalTime} min`;
  }

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

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