/**
 * OTS Signage Modern Theme - Client-Side Utilities
 * Sidebar toggle, dropdown menus, and UI interactions
 */

(function() {
  'use strict';

  // Apply saved or system-preferred theme as early as possible to avoid
  // a flash from dark -> light when navigating between pages.
  (function() {
    try {
      var stored = localStorage.getItem('ots-theme-mode');
      var prefersLight = window.matchMedia && window.matchMedia('(prefers-color-scheme: light)').matches;
      var initial = stored || (prefersLight ? 'light' : 'light');
      if (initial === 'light') {
        document.documentElement.classList.add('ots-light-mode');
        if (document.body) document.body.classList.add('ots-light-mode');
      } else {
        document.documentElement.classList.remove('ots-light-mode');
        if (document.body) document.body.classList.remove('ots-light-mode');
      }
    } catch (err) {
      // ignore failures (e.g. localStorage unavailable)
    }
  })();

  const STORAGE_KEYS = {
    sidebarCollapsed: 'otsTheme:sidebarCollapsed'
  };

  /**
   * Measure sidebar width and set CSS variable for layout
   */
  function updateSidebarWidth() {
    const sidebar = document.querySelector('.ots-sidebar');
    if (!sidebar) return;
    const collapsed = sidebar.classList.contains('collapsed');
    // If called with a forced mode, use the stored defaults
    const forceMode = updateSidebarWidth._forceMode || null;
    const base = (forceMode === 'full') ? (window.__otsFullSidebarWidth || 256)
               : (forceMode === 'collapsed') ? (window.__otsCollapsedSidebarWidth || 70)
               : (collapsed ? 70 : sidebar.offsetWidth || sidebar.getBoundingClientRect().width || 240);
    const padding = 5;
    const value = Math.max(70, Math.round(base + padding));
    // Apply CSS variable used by layout and also set an inline width fallback
    document.documentElement.style.setProperty('--ots-sidebar-width', `${value}px`);
    try {
      // Inline width helps force an immediate reflow when CSS rules/important flags interfere
      // Use setProperty with 'important' so stylesheet !important rules can't override it.
      sidebar.style.setProperty('width', `${value}px`, 'important');
      // Force reflow to encourage the browser to apply the new sizing immediately
      // eslint-disable-next-line no-unused-expressions
      sidebar.offsetHeight;
    } catch (err) {
      try { sidebar.style.width = `${value}px`; } catch (e) { /* ignore */ }
    }
    // Debug logging to help identify timing/specifity issues in the wild
    if (window.__otsDebug) {
      console.log('[OTS] updateSidebarWidth', { collapsed, base, value, cssVar: getComputedStyle(document.documentElement).getPropertyValue('--ots-sidebar-width') });
    }
  }

  // Helper to request a forced width update
  function forceSidebarWidthMode(mode) {
    updateSidebarWidth._forceMode = mode; // 'full' | 'collapsed' | null
    updateSidebarWidth();
    updateSidebarWidth._forceMode = null;
  }

  /**
   * Measure the sidebar header bottom and set the top padding of the nav list
   * so nav items always begin below the header (logo + buttons).
   */
  function updateSidebarNavOffset() {
    const sidebar = document.querySelector('.ots-sidebar');
    if (!sidebar) return;
    const header = sidebar.querySelector('.sidebar-header');
    const nav = sidebar.querySelector('.sidebar-nav, .ots-sidebar-nav');
    if (!nav) return;
    const sidebarRect = sidebar.getBoundingClientRect();
    const headerRect = header ? header.getBoundingClientRect() : null;
    let offset = 0;
    if (headerRect) {
      offset = Math.max(0, Math.ceil(headerRect.bottom - sidebarRect.top));
    } else if (header) {
      offset = header.offsetHeight || 0;
    }
    const gap = 8;
    const paddingTop = offset > 0 ? offset + gap : '';
    if (paddingTop) {
      try {
        nav.style.setProperty('padding-top', `${paddingTop}px`, 'important');
      } catch (err) {
        nav.style.paddingTop = `${paddingTop}px`;
      }
      if (window.__otsDebug) console.log('[OTS] updateSidebarNavOffset applied', { paddingTop });
    } else {
      try {
        nav.style.removeProperty('padding-top');
      } catch (err) {
        nav.style.paddingTop = '';
      }
      if (window.__otsDebug) console.log('[OTS] updateSidebarNavOffset cleared');
    }
  }

    /**
     * Measure the sidebar and set an explicit left margin on the page wrapper
     * so the gap between the sidebar and page content is exactly 5px.
     */
    function updateSidebarGap() {
      const sidebar = document.querySelector('.ots-sidebar');
      // target likely content containers in this app
      const targets = [
        document.getElementById('page-wrapper'),
        document.querySelector('.ots-main'),
        document.getElementById('content-wrapper'),
        document.querySelector('#content')
      ].filter(Boolean);
      if (!sidebar || !targets.length) return;

      const gap = (typeof window.__otsDesiredSidebarGap !== 'undefined') ? Number(window.__otsDesiredSidebarGap) : 0; // desired gap in px (default 0)
      const rect = sidebar.getBoundingClientRect();

      // desired inner left padding (allows trimming space inside the content area)
      const desiredInnerPadding = (typeof window.__otsDesiredPagePaddingLeft !== 'undefined') ? Number(window.__otsDesiredPagePaddingLeft) : 8;

      targets.forEach(pageWrapper => {
        const pageRect = pageWrapper.getBoundingClientRect();
        const computed = window.getComputedStyle(pageWrapper);
        const currentMargin = parseFloat(computed.marginLeft) || 0;
        const currentGap = Math.round(pageRect.left - rect.right);
        // Calculate how much to adjust margin-left so gap becomes `gap`.
        const delta = currentGap - gap;
        const newMargin = Math.max(0, Math.round(currentMargin - delta));
        try {
          pageWrapper.style.setProperty('margin-left', `${newMargin}px`, 'important');
          pageWrapper.style.setProperty('padding-left', `${desiredInnerPadding}px`, 'important');
        } catch (err) {
          pageWrapper.style.marginLeft = `${newMargin}px`;
          pageWrapper.style.paddingLeft = `${desiredInnerPadding}px`;
        }
        // Also adjust common child wrapper padding if present
        try {
          const inner = pageWrapper.querySelector('.page-content') || pageWrapper.querySelector('.ots-content') || pageWrapper.querySelector('.container');
          if (inner) inner.style.setProperty('padding-left', `${desiredInnerPadding}px`, 'important');
        } catch (err) {}
        if (window.__otsDebug) console.log('[OTS] updateSidebarGap', {
          target: pageWrapper.tagName + (pageWrapper.id ? '#'+pageWrapper.id : ''),
          sidebarWidth: rect.width,
          sidebarRight: rect.right,
          pageLeft: pageRect.left,
          currentGap,
          newMargin
        });

        // Detect narrow intervening elements (visual separator) and neutralize their visuals
        try {
          const sampleXs = [Math.round(rect.right + 2), Math.round((rect.right + pageRect.left) / 2), Math.round(pageRect.left - 2)];
          const ys = [Math.floor(window.innerHeight / 2), Math.floor(window.innerHeight / 4), Math.floor(window.innerHeight * 0.75)];
          const seen = new Set();
          sampleXs.forEach(x => {
            ys.forEach(y => {
              try {
                const els = document.elementsFromPoint(x, y) || [];
                els.forEach(el => {
                  if (!el || el === document.documentElement || el === document.body) return;
                  if (el === sidebar || el === pageWrapper) return;
                  const b = el.getBoundingClientRect();
                  // narrow vertical candidates between sidebar and content
                  if (b.left >= rect.right - 4 && b.right <= pageRect.left + 4 && b.width <= 80 && b.height >= 40) {
                    const id = el.tagName + (el.id ? '#'+el.id : '') + (el.className ? '.'+el.className.split(' ').join('.') : '');
                    if (seen.has(id)) return;
                    seen.add(id);
                    try {
                      el.style.setProperty('background', 'transparent', 'important');
                      el.style.setProperty('background-image', 'none', 'important');
                      el.style.setProperty('box-shadow', 'none', 'important');
                      el.style.setProperty('border', 'none', 'important');
                      el.style.setProperty('pointer-events', 'none', 'important');
                      if (window.__otsDebug) console.log('[OTS] neutralized intervening element', { id, rect: b });
                    } catch (err) {}
                  }
                });
              } catch (err) {}
            });
          });
        } catch (err) {}
      });
    }

  function debounce(fn, wait) {
    let t;
    return function () {
      clearTimeout(t);
      t = setTimeout(() => fn.apply(this, arguments), wait);
    };
  }

  /**
   * Reflect sidebar open/collapsed state on the document body
   */
  function updateSidebarStateClass() {
    const sidebar = document.querySelector('.ots-sidebar');
    if (!sidebar) return;
    const body = document.body;
    const isCollapsed = sidebar.classList.contains('collapsed');
    if (!isCollapsed) {
      body.classList.add('ots-sidebar-open');
    } else {
      body.classList.remove('ots-sidebar-open');
    }
  }

  /**
   * Initialize sidebar toggle functionality
   */
  function initSidebarToggle() {
    const toggleBtn = document.querySelector('[data-action="toggle-sidebar"]');
    const sidebar = document.querySelector('.ots-sidebar');
    const collapseBtn = document.querySelector('.sidebar-collapse-btn-visible');
    const expandBtn = document.querySelector('.sidebar-expand-btn');
    const body = document.body;

    if (!sidebar) return;

    if (toggleBtn) {
      toggleBtn.addEventListener('click', function(e) {
        e.preventDefault();
        sidebar.classList.toggle('active');
      });
    }

    if (collapseBtn) {
      const isCollapsed = localStorage.getItem(STORAGE_KEYS.sidebarCollapsed) === 'true';
      if (isCollapsed) {
        sidebar.classList.add('collapsed');
        body.classList.add('ots-sidebar-collapsed');
        updateSidebarStateClass();
        updateSidebarGap();
      }

      collapseBtn.addEventListener('click', function(e) {
        e.preventDefault();
        const nowCollapsed = !sidebar.classList.contains('collapsed');
        sidebar.classList.toggle('collapsed');
        body.classList.toggle('ots-sidebar-collapsed', nowCollapsed);
        localStorage.setItem(STORAGE_KEYS.sidebarCollapsed, nowCollapsed ? 'true' : 'false');
        // Force collapsed width immediately
        forceSidebarWidthMode('collapsed');
        // Recalculate nav offset so items remain below header after collapse
        updateSidebarNavOffset();
        // Ensure page content gap is updated for collapsed width
        updateSidebarGap();
        // Re-run shortly after to catch any late layout changes
        setTimeout(updateSidebarGap, 80);
        updateSidebarStateClass();
        // Debug state after toggle
        try {
          console.log('[OTS] collapseBtn clicked', {
            nowCollapsed,
            classes: sidebar.className,
            inlineStyle: sidebar.getAttribute('style'),
            computedWidth: getComputedStyle(sidebar).width,
            cssVar: getComputedStyle(document.documentElement).getPropertyValue('--ots-sidebar-width')
          });
        } catch (err) {}
      });
    }

    if (expandBtn) {
      expandBtn.addEventListener('click', function(e) {
        e.preventDefault();
        sidebar.classList.remove('collapsed');
        body.classList.remove('ots-sidebar-collapsed');
        localStorage.setItem(STORAGE_KEYS.sidebarCollapsed, 'false');
        // Force full width when expanding
        forceSidebarWidthMode('full');
        // Recalculate nav offset after expanding
        updateSidebarNavOffset();
        // Ensure page content gap is updated for expanded width
        updateSidebarGap();
        setTimeout(updateSidebarGap, 80);
        updateSidebarStateClass();
        try {
          console.log('[OTS] expandBtn clicked', {
            classes: sidebar.className,
            inlineStyle: sidebar.getAttribute('style'),
            computedWidth: getComputedStyle(sidebar).width,
            cssVar: getComputedStyle(document.documentElement).getPropertyValue('--ots-sidebar-width')
          });
        } catch (err) {}
      });
    }

    // Close sidebar when clicking outside on mobile
    document.addEventListener('click', function(e) {
      if (window.innerWidth <= 768) {
        const isClickInsideSidebar = sidebar.contains(e.target);
        const isClickOnToggle = toggleBtn && toggleBtn.contains(e.target);
        
        if (!isClickInsideSidebar && !isClickOnToggle && sidebar.classList.contains('active')) {
          sidebar.classList.remove('active');
          updateSidebarStateClass();
        }
      }
    });

    // Ensure initial state class is set
    updateSidebarStateClass();
  }

  /**
   * Initialize sidebar section collapse/expand functionality
   */
  function initSidebarSectionToggles() {
    const groupToggles = document.querySelectorAll('.sidebar-group-toggle');

    groupToggles.forEach(toggle => {
      const group = toggle.closest('.sidebar-group');
      const submenu = group ? group.querySelector('.sidebar-submenu') : null;
      const caret = toggle.querySelector('.sidebar-group-caret');
      if (submenu) {
        const isOpen = group.classList.contains('is-open');
        submenu.style.display = isOpen ? 'block' : 'none';
        toggle.setAttribute('aria-expanded', isOpen.toString());
      }

      toggle.addEventListener('click', function(e) {
        e.preventDefault();

        const group = toggle.closest('.sidebar-group');
        const submenu = group ? group.querySelector('.sidebar-submenu') : null;
        if (!submenu) return;

        const isOpen = group.classList.contains('is-open');
        group.classList.toggle('is-open', !isOpen);
        toggle.setAttribute('aria-expanded', (!isOpen).toString());
        submenu.style.display = isOpen ? 'none' : 'block';
      });

      if (caret) {
        caret.addEventListener('click', function(e) {
          e.preventDefault();
          e.stopPropagation();
          toggle.click();
        });
      }
    });

    // Capture-phase handler to override any conflicting listeners
    document.addEventListener('click', function(e) {
      const caret = e.target.closest('.sidebar-group-caret');
      const toggle = e.target.closest('.sidebar-group-toggle');
      const target = toggle || (caret ? caret.closest('.sidebar-group-toggle') : null);
      if (!target) return;

      e.preventDefault();
      e.stopPropagation();

      const group = target.closest('.sidebar-group');
      const submenu = group ? group.querySelector('.sidebar-submenu') : null;
      if (!submenu) return;

      const isOpen = group.classList.contains('is-open');
      group.classList.toggle('is-open', !isOpen);
      target.setAttribute('aria-expanded', (!isOpen).toString());
      submenu.style.display = isOpen ? 'none' : 'block';
    }, true);
  }

  /**
   * Initialize dropdown menus
   */
  function initDropdowns() {
    const dropdowns = document.querySelectorAll('.dropdown');
    
    dropdowns.forEach(dropdown => {
      const button = dropdown.querySelector('.dropdown-menu');
      
      if (!button) return;
      
      const menu = dropdown.querySelector('.dropdown-menu');
      
      // Toggle menu on button click
      dropdown.addEventListener('click', function(e) {
        if (e.target.closest('.user-btn') || e.target.closest('[aria-label="User menu"]') || e.target.closest('#navbarUserMenu')) {
          e.preventDefault();
          dropdown.classList.toggle('active');

          // If this dropdown contains the user menu, compute placement to avoid going off-screen
          const menu = dropdown.querySelector('.dropdown-menu.ots-user-menu');
          const trigger = dropdown.querySelector('#navbarUserMenu');
          if (menu && trigger) {
            // Reset any previous placement classes
            menu.classList.remove('dropdown-menu-left');
            menu.classList.remove('dropdown-menu-right');

            // Use getBoundingClientRect for accurate placement
            const trigRect = trigger.getBoundingClientRect();
            // Ensure menu is in DOM and has an offsetWidth
            const menuWidth = menu.offsetWidth || 220; // fallback estimate

            const spaceRight = window.innerWidth - trigRect.right;
            const spaceLeft = trigRect.left;

            // Prefer opening to the right where possible, otherwise open to the left
            if (spaceRight < menuWidth && spaceLeft > menuWidth) {
              // not enough space on the right, open to left
              menu.classList.add('dropdown-menu-left');
            } else {
              // default to right-aligned
              menu.classList.add('dropdown-menu-right');
            }
          }
        }
      });
      
      // Close menu when clicking outside
      document.addEventListener('click', function(e) {
        if (!dropdown.contains(e.target)) {
          dropdown.classList.remove('active');
        }
      });
    });
  }

  /**
   * Initialize search functionality
   */
  function initSearch() {
    const searchForm = document.querySelector('.topbar-search');
    if (!searchForm) return;

    const input = searchForm.querySelector('.search-input');
    if (input) {
      input.addEventListener('focus', function() {
        searchForm.style.borderColor = 'var(--color-primary)';
      });
      input.addEventListener('blur', function() {
        searchForm.style.borderColor = 'var(--color-border)';
      });
    }
  }

  /**
   * Initialize page specific interactions
   */
  function initPageInteractions() {
    // Displays page - folder selection
    const folderItems = document.querySelectorAll('.folder-item');
    folderItems.forEach(item => {
      item.addEventListener('click', function() {
        folderItems.forEach(f => f.classList.remove('active'));
        this.classList.add('active');
      });
    });

    // Filter collapse toggle
    const filterCollapseBtn = document.querySelector('#ots-filter-collapse-btn');
    const filterContent = document.querySelector('#ots-filter-content');
    
    if (filterCollapseBtn && filterContent) {
      const storageKey = `ots-filter-collapsed:${window.location.pathname}`;
      let isCollapsed = false;
      
      filterCollapseBtn.addEventListener('click', function() {
        isCollapsed = !isCollapsed;
        filterContent.classList.toggle('collapsed', isCollapsed);
        
        // Rotate icon
        const icon = filterCollapseBtn.querySelector('i');
        icon.classList.toggle('fa-chevron-up');
        icon.classList.toggle('fa-chevron-down');
        
        // Save preference to localStorage
        localStorage.setItem(storageKey, isCollapsed);
      });
      
      // Restore saved preference
      const savedState = localStorage.getItem(storageKey);
      if (savedState === 'true') {
        isCollapsed = true;
        filterContent.classList.add('collapsed');
        const icon = filterCollapseBtn.querySelector('i');
        icon.classList.remove('fa-chevron-up');
        icon.classList.add('fa-chevron-down');
      } else {
        filterContent.classList.remove('collapsed');
      }
    }

    // Displays page - folder tree toggle layout
    const folderToggleBtn = document.querySelector('#folder-tree-select-folder-button');
    const folderContainer = document.querySelector('.grid-with-folders-container');
    const folderTree = document.querySelector('#grid-folder-filter');

    if (folderToggleBtn && folderContainer && folderTree) {
      let debounceTimeout;
      
      const syncFolderLayout = () => {
        // Check actual visibility using computed styles
        const computedStyle = window.getComputedStyle(folderTree);
        const isHidden = computedStyle.display === 'none' || 
                        computedStyle.visibility === 'hidden' ||
                        folderTree.offsetHeight === 0;
        
        console.log('Folder collapse sync:', { 
          isHidden, 
          display: computedStyle.display,
          visibility: computedStyle.visibility,
          offsetHeight: folderTree.offsetHeight
        });
        
        folderContainer.classList.toggle('ots-folder-collapsed', !!isHidden);
        
        // Log the result
        console.log('Container classes:', folderContainer.className);
        console.log('Grid template columns:', window.getComputedStyle(folderContainer).gridTemplateColumns);
        
        // Force reflow
        folderContainer.offsetHeight;
      };
      
      const debouncedSync = () => {
        clearTimeout(debounceTimeout);
        debounceTimeout = setTimeout(syncFolderLayout, 50);
      };

      // Watch for style/class changes on folderTree (let Xibo's code run first)
      const treeObserver = new MutationObserver(() => {
        console.log('Folder tree mutation detected, debouncing sync...');
        debouncedSync();
      });
      treeObserver.observe(folderTree, { 
        attributes: true, 
        attributeFilter: ['style', 'class']
      });
      
      // Initial sync
      syncFolderLayout();
      
      // Monitor the folder tree's parent for display changes
      const parentObserver = new MutationObserver(debouncedSync);
      const treeParent = folderTree.parentElement;
      if (treeParent) {
        parentObserver.observe(treeParent, { 
          childList: false,
          attributes: true,
          subtree: false
        });
      }
    }

    // Media page - item selection
    const mediaItems = document.querySelectorAll('.media-item');
    mediaItems.forEach(item => {
      item.addEventListener('click', function() {
        this.style.opacity = '0.7';
        setTimeout(() => this.style.opacity = '1', 200);
      });
    });
  }

  /**
   * Make sidebar responsive
   */
  function makeResponsive() {
    const sidebar = document.querySelector('.ots-sidebar');
    const main = document.querySelector('.ots-main');
    
    if (!sidebar) return;
    
    // Add toggle button for mobile
    if (window.innerWidth <= 768) {
      sidebar.classList.add('mobile');
    }
    
    window.addEventListener('resize', function() {
      if (window.innerWidth > 768) {
        sidebar.classList.remove('mobile', 'active');
      } else {
        sidebar.classList.add('mobile');
      }
      updateSidebarWidth();
      updateSidebarGap();
    });
  }

  /**
   * Prevent Chart.js errors when chart elements are missing
   */
  function initChartSafeguard() {
    if (!window.Chart) return;

    if (typeof window.Chart.acquireContext === 'function') {
      window.Chart.acquireContext = function(item) {
        if (!item) return null;

        const candidate = item.length ? item[0] : item;
        if (candidate && typeof candidate.getContext === 'function') {
          return candidate.getContext('2d');
        }

        return null;
      };
      return;
    }

    if (window.Chart.prototype && typeof window.Chart.prototype.acquireContext === 'function') {
      window.Chart.prototype.acquireContext = function(item) {
        if (!item) return null;

        const candidate = item.length ? item[0] : item;
        if (candidate && typeof candidate.getContext === 'function') {
          return candidate.getContext('2d');
        }

        return null;
      };
    }
  }

  /**
   * Enhance tables: wrap in card, add per-table search box, client-side filtering
   * Non-destructive: skips tables already enhanced
   */
  function enhanceTables() {
    const selector = '.ots-content table, .content table, .container table, .card table, table';
    const tables = Array.from(document.querySelectorAll(selector));
    let counter = 0;

    tables.forEach(table => {
      // only enhance tables that have a thead and tbody
      if (!table || table.classList.contains('modern-table')) return;
      if (!table.querySelector('thead') || !table.querySelector('tbody')) return;

      counter += 1;
      table.classList.add('modern-table');

      // Build wrapper structure
      const wrapper = document.createElement('div');
      wrapper.className = 'modern-table-card';

      const controls = document.createElement('div');
      controls.className = 'table-controls';

      const input = document.createElement('input');
      input.type = 'search';
      input.placeholder = 'Search…';
      input.className = 'table-search-input';
      input.setAttribute('aria-label', 'Table search');
      input.style.minWidth = '180px';

      controls.appendChild(input);

      const tableWrapper = document.createElement('div');
      tableWrapper.className = 'table-wrapper';
      tableWrapper.style.overflow = 'auto';

      // Insert wrapper into DOM in place of the table
      const parent = table.parentNode;
      parent.replaceChild(wrapper, table);
      wrapper.appendChild(controls);
      wrapper.appendChild(tableWrapper);
      tableWrapper.appendChild(table);

      // Simple, light-weight search filtering for this table only
      input.addEventListener('input', function (e) {
        const term = (e.target.value || '').toLowerCase();
        table.querySelectorAll('tbody tr').forEach(tr => {
          const text = tr.textContent.toLowerCase();
          tr.style.display = term === '' || text.includes(term) ? '' : 'none';
        });
      });
    });
  }

  /**
   * Initialize DataTables for enhanced behavior when available.
   * Falls back gracefully if DataTables or jQuery are not present.
   */
  function initDataTables() {
    if (!window.jQuery) return;
    const $ = window.jQuery;
    if (!$.fn || !$.fn.dataTable) return;

    // Skip Xibo-managed grids to avoid double initialization
    if (document.querySelector('.XiboGrid')) return;

    $('.modern-table, table').each(function () {
      try {
        if (this.closest('.XiboGrid')) return;
        if (!$.fn.dataTable.isDataTable(this)) {
          $(this).DataTable({
            responsive: true,
            lengthChange: false,
            pageLength: 10,
            autoWidth: false,
            dom: '<"table-controls"f>rt<"table-meta"ip>',
            language: { search: '' }
          });
        }
      } catch (err) {
        // If initialization fails, ignore and allow fallback enhancer
        console.warn('DataTables init failed for table', this, err);
      }
    });
  }

  /**
   * Initialize light/dark mode toggle
   */
  function initThemeToggle() {
    const themeToggle = document.getElementById('ots-theme-toggle');
    if (!themeToggle) return;

    const storedTheme = localStorage.getItem('ots-theme-mode');
    const prefersLight = window.matchMedia && window.matchMedia('(prefers-color-scheme: light)').matches;
    const effectiveTheme = storedTheme || (prefersLight ? 'light' : 'dark');
    const body = document.body;
    const root = document.documentElement;

    // Apply stored theme on page load (apply to both <html> and <body>)
    if (effectiveTheme === 'light') {
      body.classList.add('ots-light-mode');
      root.classList.add('ots-light-mode');
      updateThemeLabel();
    }

    // Toggle on click (keep <html> in sync so :root variables reflect mode)
    themeToggle.addEventListener('click', function(e) {
      e.preventDefault();
      const isLight = body.classList.toggle('ots-light-mode');
      root.classList.toggle('ots-light-mode', isLight);
      localStorage.setItem('ots-theme-mode', isLight ? 'light' : 'dark');
      updateThemeLabel();
    });

    function updateThemeLabel() {
      const icon = document.getElementById('ots-theme-icon');
      const label = document.getElementById('ots-theme-label');
      const isLight = body.classList.contains('ots-light-mode');
      if (icon) {
        icon.className = isLight ? 'fa fa-sun-o' : 'fa fa-moon-o';
      }
      if (label) {
        label.textContent = isLight ? 'Light Mode' : 'Dark Mode';
      }
    }
  }

  /**
   * Initialize all features when DOM is ready
   */
  function init() {
    initSidebarToggle();
    initSidebarSectionToggles();
    initThemeToggle();
    initDropdowns();
    initSearch();
    initPageInteractions();
    initDataTables();
    enhanceTables();
    makeResponsive();
    initChartSafeguard();
    updateSidebarWidth();
    updateSidebarNavOffset();
    updateSidebarGap();
    var debouncedUpdate = debounce(function() {
      updateSidebarNavOffset();
      updateSidebarWidth();
      updateSidebarGap();
    }, 120);
    window.addEventListener('resize', debouncedUpdate);
  }

  // Wait for DOM to be ready
  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', init);
  } else {
    init();
  }
})();