Super_Assistant/chrome-extension/public/buildDomTree.js

window.buildDomTree = (
  args = {
    doHighlightElements: true,
    focusHighlightIndex: -1,
    viewportExpansion: 0,
    debugMode: false,
  },
) => {
  const { doHighlightElements, focusHighlightIndex, viewportExpansion, debugMode } = args;
  let highlightIndex = 0; // Reset highlight index

  // Add timing stack to handle recursion
  const TIMING_STACK = {
    nodeProcessing: [],
    treeTraversal: [],
    highlighting: [],
    current: null,
  };

  function pushTiming(type) {
    TIMING_STACK[type] = TIMING_STACK[type] || [];
    TIMING_STACK[type].push(performance.now());
  }

  function popTiming(type) {
    const start = TIMING_STACK[type].pop();
    const duration = performance.now() - start;
    return duration;
  }

  // Only initialize performance tracking if in debug mode
  const PERF_METRICS = debugMode
    ? {
        buildDomTreeCalls: 0,
        timings: {
          buildDomTree: 0,
          highlightElement: 0,
          isInteractiveElement: 0,
          isElementVisible: 0,
          isTopElement: 0,
          isInExpandedViewport: 0,
          isTextNodeVisible: 0,
          getEffectiveScroll: 0,
        },
        cacheMetrics: {
          boundingRectCacheHits: 0,
          boundingRectCacheMisses: 0,
          computedStyleCacheHits: 0,
          computedStyleCacheMisses: 0,
          getBoundingClientRectTime: 0,
          getComputedStyleTime: 0,
          boundingRectHitRate: 0,
          computedStyleHitRate: 0,
          overallHitRate: 0,
        },
        nodeMetrics: {
          totalNodes: 0,
          processedNodes: 0,
          skippedNodes: 0,
        },
        buildDomTreeBreakdown: {
          totalTime: 0,
          totalSelfTime: 0,
          buildDomTreeCalls: 0,
          domOperations: {
            getBoundingClientRect: 0,
            getComputedStyle: 0,
          },
          domOperationCounts: {
            getBoundingClientRect: 0,
            getComputedStyle: 0,
          },
        },
      }
    : null;

  // Simple timing helper that only runs in debug mode
  function measureTime(fn) {
    if (!debugMode) return fn;
    return function (...args) {
      const start = performance.now();
      const result = fn.apply(this, args);
      const duration = performance.now() - start;
      return result;
    };
  }

  // Helper to measure DOM operations
  function measureDomOperation(operation, name) {
    if (!debugMode) return operation();

    const start = performance.now();
    const result = operation();
    const duration = performance.now() - start;

    if (PERF_METRICS && name in PERF_METRICS.buildDomTreeBreakdown.domOperations) {
      PERF_METRICS.buildDomTreeBreakdown.domOperations[name] += duration;
      PERF_METRICS.buildDomTreeBreakdown.domOperationCounts[name]++;
    }

    return result;
  }

  // Add caching mechanisms at the top level
  const DOM_CACHE = {
    boundingRects: new WeakMap(),
    computedStyles: new WeakMap(),
    clearCache: () => {
      DOM_CACHE.boundingRects = new WeakMap();
      DOM_CACHE.computedStyles = new WeakMap();
    },
  };

  // Cache helper functions
  function getCachedBoundingRect(element) {
    if (!element) return null;

    if (DOM_CACHE.boundingRects.has(element)) {
      if (debugMode && PERF_METRICS) {
        PERF_METRICS.cacheMetrics.boundingRectCacheHits++;
      }
      return DOM_CACHE.boundingRects.get(element);
    }

    if (debugMode && PERF_METRICS) {
      PERF_METRICS.cacheMetrics.boundingRectCacheMisses++;
    }

    let rect;
    if (debugMode) {
      const start = performance.now();
      rect = element.getBoundingClientRect();
      const duration = performance.now() - start;
      if (PERF_METRICS) {
        PERF_METRICS.buildDomTreeBreakdown.domOperations.getBoundingClientRect += duration;
        PERF_METRICS.buildDomTreeBreakdown.domOperationCounts.getBoundingClientRect++;
      }
    } else {
      rect = element.getBoundingClientRect();
    }

    if (rect) {
      DOM_CACHE.boundingRects.set(element, rect);
    }
    return rect;
  }

  function getCachedComputedStyle(element) {
    if (!element) return null;

    if (DOM_CACHE.computedStyles.has(element)) {
      if (debugMode && PERF_METRICS) {
        PERF_METRICS.cacheMetrics.computedStyleCacheHits++;
      }
      return DOM_CACHE.computedStyles.get(element);
    }

    if (debugMode && PERF_METRICS) {
      PERF_METRICS.cacheMetrics.computedStyleCacheMisses++;
    }

    let style;
    if (debugMode) {
      const start = performance.now();
      style = window.getComputedStyle(element);
      const duration = performance.now() - start;
      if (PERF_METRICS) {
        PERF_METRICS.buildDomTreeBreakdown.domOperations.getComputedStyle += duration;
        PERF_METRICS.buildDomTreeBreakdown.domOperationCounts.getComputedStyle++;
      }
    } else {
      style = window.getComputedStyle(element);
    }

    if (style) {
      DOM_CACHE.computedStyles.set(element, style);
    }
    return style;
  }

  /**
   * Hash map of DOM nodes indexed by their highlight index.
   *
   * @type {Object<string, any>}
   */
  const DOM_HASH_MAP = {};

  const ID = { current: 0 };

  const HIGHLIGHT_CONTAINER_ID = 'playwright-highlight-container';

  /**
   * Highlights an element in the DOM and returns the index of the next element.
   */
  function highlightElement(element, index, parentIframe = null) {
    if (!element) return index;

    // Store overlays and the single label for updating
    const overlays = [];
    let label = null;
    let labelWidth = 20; // Approximate label width
    let labelHeight = 16; // Approximate label height

    try {
      // Create or get highlight container
      let container = document.getElementById(HIGHLIGHT_CONTAINER_ID);
      if (!container) {
        container = document.createElement('div');
        container.id = HIGHLIGHT_CONTAINER_ID;
        container.style.position = 'fixed';
        container.style.pointerEvents = 'none';
        container.style.top = '0';
        container.style.left = '0';
        container.style.width = '100%';
        container.style.height = '100%';
        container.style.zIndex = '2147483647';
        document.body.appendChild(container);
      }

      // Get element client rects
      const rects = element.getClientRects(); // Use getClientRects()

      if (!rects || rects.length === 0) return index; // Exit if no rects

      // Generate a color based on the index
      const colors = [
        '#FF0000',
        '#00FF00',
        '#0000FF',
        '#FFA500',
        '#800080',
        '#008080',
        '#FF69B4',
        '#4B0082',
        '#FF4500',
        '#2E8B57',
        '#DC143C',
        '#4682B4',
      ];
      const colorIndex = index % colors.length;
      const baseColor = colors[colorIndex];
      const backgroundColor = baseColor + '1A'; // 10% opacity version of the color

      // Get iframe offset if necessary
      let iframeOffset = { x: 0, y: 0 };
      if (parentIframe) {
        const iframeRect = parentIframe.getBoundingClientRect(); // Keep getBoundingClientRect for iframe offset
        iframeOffset.x = iframeRect.left;
        iframeOffset.y = iframeRect.top;
      }

      // Create highlight overlays for each client rect
      for (const rect of rects) {
        if (rect.width === 0 || rect.height === 0) continue; // Skip empty rects

        const overlay = document.createElement('div');
        overlay.style.position = 'fixed';
        overlay.style.border = `2px solid ${baseColor}`;
        overlay.style.backgroundColor = backgroundColor;
        overlay.style.pointerEvents = 'none';
        overlay.style.boxSizing = 'border-box';

        const top = rect.top + iframeOffset.y;
        const left = rect.left + iframeOffset.x;

        overlay.style.top = `${top}px`;
        overlay.style.left = `${left}px`;
        overlay.style.width = `${rect.width}px`;
        overlay.style.height = `${rect.height}px`;

        container.appendChild(overlay);
        overlays.push({ element: overlay, initialRect: rect }); // Store overlay and its rect
      }

      // Create and position a single label relative to the first rect
      const firstRect = rects[0];
      label = document.createElement('div');
      label.className = 'playwright-highlight-label';
      label.style.position = 'fixed';
      label.style.background = baseColor;
      label.style.color = 'white';
      label.style.padding = '1px 4px';
      label.style.borderRadius = '4px';
      label.style.fontSize = `${Math.min(12, Math.max(8, firstRect.height / 2))}px`;
      label.textContent = index;

      labelWidth = label.offsetWidth > 0 ? label.offsetWidth : labelWidth; // Update actual width if possible
      labelHeight = label.offsetHeight > 0 ? label.offsetHeight : labelHeight; // Update actual height if possible

      const firstRectTop = firstRect.top + iframeOffset.y;
      const firstRectLeft = firstRect.left + iframeOffset.x;

      let labelTop = firstRectTop + 2;
      let labelLeft = firstRectLeft + firstRect.width - labelWidth - 2;

      // Adjust label position if first rect is too small
      if (firstRect.width < labelWidth + 4 || firstRect.height < labelHeight + 4) {
        labelTop = firstRectTop - labelHeight - 2;
        labelLeft = firstRectLeft + firstRect.width - labelWidth; // Align with right edge
        if (labelLeft < iframeOffset.x) labelLeft = firstRectLeft; // Prevent going off-left
      }

      // Ensure label stays within viewport bounds slightly better
      labelTop = Math.max(0, Math.min(labelTop, window.innerHeight - labelHeight));
      labelLeft = Math.max(0, Math.min(labelLeft, window.innerWidth - labelWidth));

      label.style.top = `${labelTop}px`;
      label.style.left = `${labelLeft}px`;

      container.appendChild(label);

      // Update positions on scroll/resize
      const updatePositions = () => {
        const newRects = element.getClientRects(); // Get fresh rects
        let newIframeOffset = { x: 0, y: 0 };

        if (parentIframe) {
          const iframeRect = parentIframe.getBoundingClientRect(); // Keep getBoundingClientRect for iframe
          newIframeOffset.x = iframeRect.left;
          newIframeOffset.y = iframeRect.top;
        }

        // Update each overlay
        overlays.forEach((overlayData, i) => {
          if (i < newRects.length) {
            // Check if rect still exists
            const newRect = newRects[i];
            const newTop = newRect.top + newIframeOffset.y;
            const newLeft = newRect.left + newIframeOffset.x;

            overlayData.element.style.top = `${newTop}px`;
            overlayData.element.style.left = `${newLeft}px`;
            overlayData.element.style.width = `${newRect.width}px`;
            overlayData.element.style.height = `${newRect.height}px`;
            overlayData.element.style.display = newRect.width === 0 || newRect.height === 0 ? 'none' : 'block';
          } else {
            // If fewer rects now, hide extra overlays
            overlayData.element.style.display = 'none';
          }
        });

        // If there are fewer new rects than overlays, hide the extras
        if (newRects.length < overlays.length) {
          for (let i = newRects.length; i < overlays.length; i++) {
            overlays[i].element.style.display = 'none';
          }
        }

        // Update label position based on the first new rect
        if (label && newRects.length > 0) {
          const firstNewRect = newRects[0];
          const firstNewRectTop = firstNewRect.top + newIframeOffset.y;
          const firstNewRectLeft = firstNewRect.left + newIframeOffset.x;

          let newLabelTop = firstNewRectTop + 2;
          let newLabelLeft = firstNewRectLeft + firstNewRect.width - labelWidth - 2;

          if (firstNewRect.width < labelWidth + 4 || firstNewRect.height < labelHeight + 4) {
            newLabelTop = firstNewRectTop - labelHeight - 2;
            newLabelLeft = firstNewRectLeft + firstNewRect.width - labelWidth;
            if (newLabelLeft < newIframeOffset.x) newLabelLeft = firstNewRectLeft;
          }

          // Ensure label stays within viewport bounds
          newLabelTop = Math.max(0, Math.min(newLabelTop, window.innerHeight - labelHeight));
          newLabelLeft = Math.max(0, Math.min(newLabelLeft, window.innerWidth - labelWidth));

          label.style.top = `${newLabelTop}px`;
          label.style.left = `${newLabelLeft}px`;
          label.style.display = 'block';
        } else if (label) {
          // Hide label if element has no rects anymore
          label.style.display = 'none';
        }
      };

      window.addEventListener('scroll', updatePositions, true); // Use capture phase
      window.addEventListener('resize', updatePositions);

      // TODO: Add cleanup logic to remove listeners and elements when done.

      return index + 1;
    } finally {
      // popTiming('highlighting'); // Assuming this was a typo and should be removed or corrected
    }
  }

  /**
   * Returns an XPath tree string for an element.
   */
  function getXPathTree(element, stopAtBoundary = true) {
    const segments = [];
    let currentElement = element;

    while (currentElement && currentElement.nodeType === Node.ELEMENT_NODE) {
      // Stop if we hit a shadow root or iframe
      if (
        stopAtBoundary &&
        (currentElement.parentNode instanceof ShadowRoot || currentElement.parentNode instanceof HTMLIFrameElement)
      ) {
        break;
      }

      let index = 0;
      let sibling = currentElement.previousSibling;
      while (sibling) {
        if (sibling.nodeType === Node.ELEMENT_NODE && sibling.nodeName === currentElement.nodeName) {
          index++;
        }
        sibling = sibling.previousSibling;
      }

      const tagName = currentElement.nodeName.toLowerCase();
      const xpathIndex = index > 0 ? `[${index + 1}]` : '';
      segments.unshift(`${tagName}${xpathIndex}`);

      currentElement = currentElement.parentNode;
    }

    return segments.join('/');
  }

  /**
   * Checks if a text node is visible.
   */
  function isTextNodeVisible(textNode) {
    try {
      const range = document.createRange();
      range.selectNodeContents(textNode);
      const rects = range.getClientRects(); // Use getClientRects for Range

      if (!rects || rects.length === 0) {
        return false;
      }

      let isAnyRectVisible = false;
      let isAnyRectInViewport = false;

      for (const rect of rects) {
        // Check size
        if (rect.width > 0 && rect.height > 0) {
          isAnyRectVisible = true;

          // Viewport check for this rect
          if (
            !(
              rect.bottom < -viewportExpansion ||
              rect.top > window.innerHeight + viewportExpansion ||
              rect.right < -viewportExpansion ||
              rect.left > window.innerWidth + viewportExpansion
            ) ||
            viewportExpansion === -1
          ) {
            isAnyRectInViewport = true;
            break; // Found a visible rect in viewport, no need to check others
          }
        }
      }

      if (!isAnyRectVisible || !isAnyRectInViewport) {
        return false;
      }

      // Check parent visibility
      const parentElement = textNode.parentElement;
      if (!parentElement) return false;

      try {
        return (
          isInViewport &&
          parentElement.checkVisibility({
            checkOpacity: true,
            checkVisibilityCSS: true,
          })
        );
      } catch (e) {
        // Fallback if checkVisibility is not supported
        const style = window.getComputedStyle(parentElement);
        return isInViewport && style.display !== 'none' && style.visibility !== 'hidden' && style.opacity !== '0';
      }
    } catch (e) {
      console.warn('Error checking text node visibility:', e);
      return false;
    }
  }

  // Helper function to check if element is accepted
  function isElementAccepted(element) {
    if (!element || !element.tagName) return false;

    // Always accept body and common container elements
    const alwaysAccept = new Set(['body', 'div', 'main', 'article', 'section', 'nav', 'header', 'footer']);
    const tagName = element.tagName.toLowerCase();

    if (alwaysAccept.has(tagName)) return true;

    const leafElementDenyList = new Set(['svg', 'script', 'style', 'link', 'meta', 'noscript', 'template']);

    return !leafElementDenyList.has(tagName);
  }

  /**
   * Checks if an element is visible.
   */
  function isElementVisible(element) {
    const style = getCachedComputedStyle(element);
    return (
      element.offsetWidth > 0 && element.offsetHeight > 0 && style.visibility !== 'hidden' && style.display !== 'none'
    );
  }

  /**
   * Checks if an element is interactive.
   *
   * lots of comments, and uncommented code - to show the logic of what we already tried
   *
   * One of the things we tried at the beginning was also to use event listeners, and other fancy class, style stuff -> what actually worked best was just combining most things with computed cursor style :)
   */
  function isInteractiveElement(element) {
    if (!element || element.nodeType !== Node.ELEMENT_NODE) {
      return false;
    }

    // Define interactive cursors
    const interactiveCursors = new Set([
      'pointer', // Link/clickable elements
      'move', // Movable elements
      'text', // Text selection
      'grab', // Grabbable elements
      'grabbing', // Currently grabbing
      'cell', // Table cell selection
      'copy', // Copy operation
      'alias', // Alias creation
      'all-scroll', // Scrollable content
      'col-resize', // Column resize
      'context-menu', // Context menu available
      'crosshair', // Precise selection
      'e-resize', // East resize
      'ew-resize', // East-west resize
      'help', // Help available
      'n-resize', // North resize
      'ne-resize', // Northeast resize
      'nesw-resize', // Northeast-southwest resize
      'ns-resize', // North-south resize
      'nw-resize', // Northwest resize
      'nwse-resize', // Northwest-southeast resize
      'row-resize', // Row resize
      's-resize', // South resize
      'se-resize', // Southeast resize
      'sw-resize', // Southwest resize
      'vertical-text', // Vertical text selection
      'w-resize', // West resize
      'zoom-in', // Zoom in
      'zoom-out', // Zoom out
    ]);

    // Define non-interactive cursors
    const nonInteractiveCursors = new Set([
      'not-allowed', // Action not allowed
      'no-drop', // Drop not allowed
      'wait', // Processing
      'progress', // In progress
      'initial', // Initial value
      'inherit', // Inherited value
      //? Let's just include all potentially clickable elements that are not specifically blocked
      // 'none',        // No cursor
      // 'default',     // Default cursor
      // 'auto',        // Browser default
    ]);

    function doesElementHaveInteractivePointer(element) {
      if (element.tagName.toLowerCase() === 'html') return false;
      const style = getCachedComputedStyle(element);

      if (interactiveCursors.has(style.cursor)) return true;

      return false;
    }

    let isInteractiveCursor = doesElementHaveInteractivePointer(element);

    // Genius fix for almost all interactive elements
    if (isInteractiveCursor) {
      return true;
    }

    const interactiveElements = new Set([
      'a', // Links
      'button', // Buttons
      'input', // All input types (text, checkbox, radio, etc.)
      'select', // Dropdown menus
      'textarea', // Text areas
      'details', // Expandable details
      'summary', // Summary element (clickable part of details)
      'label', // Form labels (often clickable)
      'option', // Select options
      'optgroup', // Option groups
      'fieldset', // Form fieldsets (can be interactive with legend)
      'legend', // Fieldset legends
    ]);

    // Define explicit disable attributes and properties
    const explicitDisableTags = new Set([
      'disabled', // Standard disabled attribute
      // 'aria-disabled',      // ARIA disabled state
      'readonly', // Read-only state
      // 'aria-readonly',     // ARIA read-only state
      // 'aria-hidden',       // Hidden from accessibility
      // 'hidden',            // Hidden attribute
      // 'inert',             // Inert attribute
      // 'aria-inert',        // ARIA inert state
      // 'tabindex="-1"',     // Removed from tab order
      // 'aria-hidden="true"' // Hidden from screen readers
    ]);

    // handle inputs, select, checkbox, radio, textarea, button and make sure they are not cursor style disabled/not-allowed
    if (interactiveElements.has(element.tagName.toLowerCase())) {
      const style = getCachedComputedStyle(element);

      // Check for non-interactive cursor
      if (nonInteractiveCursors.has(style.cursor)) {
        return false;
      }

      // Check for explicit disable attributes
      for (const disableTag of explicitDisableTags) {
        if (
          element.hasAttribute(disableTag) ||
          element.getAttribute(disableTag) === 'true' ||
          element.getAttribute(disableTag) === ''
        ) {
          return false;
        }
      }

      // Check for disabled property on form elements
      if (element.disabled) {
        return false;
      }

      // Check for readonly property on form elements
      if (element.readOnly) {
        return false;
      }

      // Check for inert property
      if (element.inert) {
        return false;
      }

      return true;
    }

    const tagName = element.tagName.toLowerCase();
    const role = element.getAttribute('role');
    const ariaRole = element.getAttribute('aria-role');

    // Added enhancement to capture dropdown interactive elements
    if (
      element.classList &&
      (element.classList.contains('button') ||
        element.classList.contains('dropdown-toggle') ||
        element.getAttribute('data-index') ||
        element.getAttribute('data-toggle') === 'dropdown' ||
        element.getAttribute('aria-haspopup') === 'true')
    ) {
      return true;
    }

    const interactiveRoles = new Set([
      'button', // Directly clickable element
      // 'link',            // Clickable link
      // 'menuitem',        // Clickable menu item
      'menuitemradio', // Radio-style menu item (selectable)
      'menuitemcheckbox', // Checkbox-style menu item (toggleable)
      'radio', // Radio button (selectable)
      'checkbox', // Checkbox (toggleable)
      'tab', // Tab (clickable to switch content)
      'switch', // Toggle switch (clickable to change state)
      'slider', // Slider control (draggable)
      'spinbutton', // Number input with up/down controls
      'combobox', // Dropdown with text input
      'searchbox', // Search input field
      'textbox', // Text input field
      // 'listbox',         // Selectable list
      'option', // Selectable option in a list
      'scrollbar', // Scrollable control
    ]);

    // Basic role/attribute checks
    const hasInteractiveRole =
      interactiveElements.has(tagName) || interactiveRoles.has(role) || interactiveRoles.has(ariaRole);

    if (hasInteractiveRole) return true;

    // check whether element has event listeners
    try {
      if (typeof getEventListeners === 'function') {
        const listeners = getEventListeners(element);
        const mouseEvents = ['click', 'mousedown', 'mouseup', 'dblclick'];
        for (const eventType of mouseEvents) {
          if (listeners[eventType] && listeners[eventType].length > 0) {
            return true; // Found a mouse interaction listener
          }
        }
      } else {
        // Fallback: Check common event attributes if getEventListeners is not available
        const commonMouseAttrs = ['onclick', 'onmousedown', 'onmouseup', 'ondblclick'];
        if (commonMouseAttrs.some(attr => element.hasAttribute(attr))) {
          return true;
        }
      }
    } catch (e) {
      // console.warn(`Could not check event listeners for ${element.tagName}:`, e);
      // If checking listeners fails, rely on other checks
    }

    return false;
  }

  /**
   * Checks if an element is the topmost element at its position.
   */
  function isTopElement(element) {
    const rects = element.getClientRects(); // Use getClientRects

    if (!rects || rects.length === 0) {
      return false; // No geometry, cannot be top
    }

    let isAnyRectInViewport = false;
    for (const rect of rects) {
      // Use the same logic as isInExpandedViewport check
      if (
        (rect.width > 0 &&
          rect.height > 0 &&
          !(
            // Only check non-empty rects
            (
              rect.bottom < -viewportExpansion ||
              rect.top > window.innerHeight + viewportExpansion ||
              rect.right < -viewportExpansion ||
              rect.left > window.innerWidth + viewportExpansion
            )
          )) ||
        viewportExpansion === -1
      ) {
        isAnyRectInViewport = true;
        break;
      }
    }

    if (!isAnyRectInViewport) {
      return false; // All rects are outside the viewport area
    }

    // Find the correct document context and root element
    let doc = element.ownerDocument;

    // If we're in an iframe, elements are considered top by default
    if (doc !== window.document) {
      return true;
    }

    // For shadow DOM, we need to check within its own root context
    const shadowRoot = element.getRootNode();
    if (shadowRoot instanceof ShadowRoot) {
      const centerX = rects[Math.floor(rects.length / 2)].left + rects[Math.floor(rects.length / 2)].width / 2;
      const centerY = rects[Math.floor(rects.length / 2)].top + rects[Math.floor(rects.length / 2)].height / 2;

      try {
        const topEl = measureDomOperation(() => shadowRoot.elementFromPoint(centerX, centerY), 'elementFromPoint');
        if (!topEl) return false;

        let current = topEl;
        while (current && current !== shadowRoot) {
          if (current === element) return true;
          current = current.parentElement;
        }
        return false;
      } catch (e) {
        return true;
      }
    }

    // For elements in viewport, check if they're topmost
    const centerX = rects[Math.floor(rects.length / 2)].left + rects[Math.floor(rects.length / 2)].width / 2;
    const centerY = rects[Math.floor(rects.length / 2)].top + rects[Math.floor(rects.length / 2)].height / 2;

    try {
      const topEl = document.elementFromPoint(centerX, centerY);
      if (!topEl) return false;

      let current = topEl;
      while (current && current !== document.documentElement) {
        if (current === element) return true;
        current = current.parentElement;
      }
      return false;
    } catch (e) {
      return true;
    }
  }

  /**
   * Checks if an element is within the expanded viewport.
   */
  function isInExpandedViewport(element, viewportExpansion) {
    return true;

    if (viewportExpansion === -1) {
      return true;
    }

    const rects = element.getClientRects(); // Use getClientRects

    if (!rects || rects.length === 0) {
      // Fallback to getBoundingClientRect if getClientRects is empty,
      // useful for elements like <svg> that might not have client rects but have a bounding box.
      const boundingRect = getCachedBoundingRect(element);
      if (!boundingRect || boundingRect.width === 0 || boundingRect.height === 0) {
        return false;
      }
      return !(
        boundingRect.bottom < -viewportExpansion ||
        boundingRect.top > window.innerHeight + viewportExpansion ||
        boundingRect.right < -viewportExpansion ||
        boundingRect.left > window.innerWidth + viewportExpansion
      );
    }

    // Check if *any* client rect is within the viewport
    for (const rect of rects) {
      if (rect.width === 0 || rect.height === 0) continue; // Skip empty rects

      if (
        !(
          rect.bottom < -viewportExpansion ||
          rect.top > window.innerHeight + viewportExpansion ||
          rect.right < -viewportExpansion ||
          rect.left > window.innerWidth + viewportExpansion
        )
      ) {
        return true; // Found at least one rect in the viewport
      }
    }

    return false; // No rects were found in the viewport
  }

  // Add this new helper function
  function getEffectiveScroll(element) {
    let currentEl = element;
    let scrollX = 0;
    let scrollY = 0;

    return measureDomOperation(() => {
      while (currentEl && currentEl !== document.documentElement) {
        if (currentEl.scrollLeft || currentEl.scrollTop) {
          scrollX += currentEl.scrollLeft;
          scrollY += currentEl.scrollTop;
        }
        currentEl = currentEl.parentElement;
      }

      scrollX += window.scrollX;
      scrollY += window.scrollY;

      return { scrollX, scrollY };
    }, 'scrollOperations');
  }

  // Add these helper functions at the top level
  function isInteractiveCandidate(element) {
    if (!element || element.nodeType !== Node.ELEMENT_NODE) return false;

    const tagName = element.tagName.toLowerCase();

    // Fast-path for common interactive elements
    const interactiveElements = new Set(['a', 'button', 'input', 'select', 'textarea', 'details', 'summary']);

    if (interactiveElements.has(tagName)) return true;

    // Quick attribute checks without getting full lists
    const hasQuickInteractiveAttr =
      element.hasAttribute('onclick') ||
      element.hasAttribute('role') ||
      element.hasAttribute('tabindex') ||
      element.hasAttribute('aria-') ||
      element.hasAttribute('data-action') ||
      element.getAttribute('contenteditable') == 'true';

    return hasQuickInteractiveAttr;
  }

  // --- Define constants for distinct interaction check ---
  const DISTINCT_INTERACTIVE_TAGS = new Set([
    'a',
    'button',
    'input',
    'select',
    'textarea',
    'summary',
    'details',
    'label',
    'option',
  ]);
  const INTERACTIVE_ROLES = new Set([
    'button',
    'link',
    'menuitem',
    'menuitemradio',
    'menuitemcheckbox',
    'radio',
    'checkbox',
    'tab',
    'switch',
    'slider',
    'spinbutton',
    'combobox',
    'searchbox',
    'textbox',
    'listbox',
    'option',
    'scrollbar',
  ]);

  /**
   * Checks if an element likely represents a distinct interaction
   * separate from its parent (if the parent is also interactive).
   */
  function isElementDistinctInteraction(element) {
    if (!element || element.nodeType !== Node.ELEMENT_NODE) {
      return false;
    }

    const tagName = element.tagName.toLowerCase();
    const role = element.getAttribute('role');

    // Check if it's an iframe - always distinct boundary
    if (tagName === 'iframe') {
      return true;
    }

    // Check tag name
    if (DISTINCT_INTERACTIVE_TAGS.has(tagName)) {
      return true;
    }
    // Check interactive roles
    if (role && INTERACTIVE_ROLES.has(role)) {
      return true;
    }
    // Check contenteditable
    if (element.isContentEditable || element.getAttribute('contenteditable') === 'true') {
      return true;
    }
    // Check for common testing/automation attributes
    if (element.hasAttribute('data-testid') || element.hasAttribute('data-cy') || element.hasAttribute('data-test')) {
      return true;
    }
    // Check for explicit onclick handler (attribute or property)
    if (element.hasAttribute('onclick') || typeof element.onclick === 'function') {
      return true;
    }
    // Check for other common interaction event listeners
    try {
      if (typeof getEventListeners === 'function') {
        const listeners = getEventListeners(element);
        const interactionEvents = [
          'mousedown',
          'mouseup',
          'keydown',
          'keyup',
          'submit',
          'change',
          'input',
          'focus',
          'blur',
        ];
        for (const eventType of interactionEvents) {
          if (listeners[eventType] && listeners[eventType].length > 0) {
            return true; // Found a common interaction listener
          }
        }
      } else {
        // Fallback: Check common event attributes if getEventListeners is not available
        const commonEventAttrs = [
          'onmousedown',
          'onmouseup',
          'onkeydown',
          'onkeyup',
          'onsubmit',
          'onchange',
          'oninput',
          'onfocus',
          'onblur',
        ];
        if (commonEventAttrs.some(attr => element.hasAttribute(attr))) {
          return true;
        }
      }
    } catch (e) {
      // console.warn(`Could not check event listeners for ${element.tagName}:`, e);
      // If checking listeners fails, rely on other checks
    }

    // Default to false: if it's interactive but doesn't match above,
    // assume it triggers the same action as the parent.
    return false;
  }
  // --- End distinct interaction check ---

  /**
   * Handles the logic for deciding whether to highlight an element and performing the highlight.
   */
  function handleHighlighting(nodeData, node, parentIframe, isParentHighlighted) {
    if (!nodeData.isInteractive) return false; // Not interactive, definitely don't highlight

    let shouldHighlight = false;
    if (!isParentHighlighted) {
      // Parent wasn't highlighted, this interactive node can be highlighted.
      shouldHighlight = true;
    } else {
      // Parent *was* highlighted. Only highlight this node if it represents a distinct interaction.
      if (isElementDistinctInteraction(node)) {
        shouldHighlight = true;
      } else {
        // console.log(`Skipping highlight for ${nodeData.tagName} (parent highlighted)`);
        shouldHighlight = false;
      }
    }

    if (shouldHighlight) {
      // Check viewport status before assigning index and highlighting
      nodeData.isInViewport = isInExpandedViewport(node, viewportExpansion);
      if (nodeData.isInViewport) {
        nodeData.highlightIndex = highlightIndex++;

        if (doHighlightElements) {
          if (focusHighlightIndex >= 0) {
            if (focusHighlightIndex === nodeData.highlightIndex) {
              highlightElement(node, nodeData.highlightIndex, parentIframe);
            }
          } else {
            highlightElement(node, nodeData.highlightIndex, parentIframe);
          }
          return true; // Successfully highlighted
        }
      } else {
        // console.log(`Skipping highlight for ${nodeData.tagName} (outside viewport)`);
      }
    }

    return false; // Did not highlight
  }

  /**
   * Creates a node data object for a given node and its descendants.
   */
  function buildDomTree(node, parentIframe = null, isParentHighlighted = false) {
    if (debugMode) PERF_METRICS.nodeMetrics.totalNodes++;

    if (!node || node.id === HIGHLIGHT_CONTAINER_ID) {
      if (debugMode) PERF_METRICS.nodeMetrics.skippedNodes++;
      return null;
    }

    // Special handling for root node (body)
    if (node === document.body) {
      const nodeData = {
        tagName: 'body',
        attributes: {},
        xpath: '/body',
        children: [],
      };

      // Process children of body
      for (const child of node.childNodes) {
        const domElement = buildDomTree(child, parentIframe, false); // Body's children have no highlighted parent initially
        if (domElement) nodeData.children.push(domElement);
      }

      const id = `${ID.current++}`;
      DOM_HASH_MAP[id] = nodeData;
      if (debugMode) PERF_METRICS.nodeMetrics.processedNodes++;
      return id;
    }

    // Early bailout for non-element nodes except text
    if (node.nodeType !== Node.ELEMENT_NODE && node.nodeType !== Node.TEXT_NODE) {
      if (debugMode) PERF_METRICS.nodeMetrics.skippedNodes++;
      return null;
    }

    // Process text nodes
    if (node.nodeType === Node.TEXT_NODE) {
      const textContent = node.textContent.trim();
      if (!textContent) {
        if (debugMode) PERF_METRICS.nodeMetrics.skippedNodes++;
        return null;
      }

      // Only check visibility for text nodes that might be visible
      const parentElement = node.parentElement;
      if (!parentElement || parentElement.tagName.toLowerCase() === 'script') {
        if (debugMode) PERF_METRICS.nodeMetrics.skippedNodes++;
        return null;
      }

      const id = `${ID.current++}`;
      DOM_HASH_MAP[id] = {
        type: 'TEXT_NODE',
        text: textContent,
        isVisible: isTextNodeVisible(node),
      };
      if (debugMode) PERF_METRICS.nodeMetrics.processedNodes++;
      return id;
    }

    // Quick checks for element nodes
    if (node.nodeType === Node.ELEMENT_NODE && !isElementAccepted(node)) {
      if (debugMode) PERF_METRICS.nodeMetrics.skippedNodes++;
      return null;
    }

    // Early viewport check - only filter out elements clearly outside viewport
    if (viewportExpansion !== -1) {
      const rect = getCachedBoundingRect(node); // Keep for initial quick check
      const style = getCachedComputedStyle(node);

      // Skip viewport check for fixed/sticky elements as they may appear anywhere
      const isFixedOrSticky = style && (style.position === 'fixed' || style.position === 'sticky');

      // Check if element has actual dimensions using offsetWidth/Height (quick check)
      const hasSize = node.offsetWidth > 0 || node.offsetHeight > 0;

      // Use getBoundingClientRect for the quick OUTSIDE check.
      // isInExpandedViewport will do the more accurate check later if needed.
      if (
        !rect ||
        (!isFixedOrSticky &&
          !hasSize &&
          (rect.bottom < -viewportExpansion ||
            rect.top > window.innerHeight + viewportExpansion ||
            rect.right < -viewportExpansion ||
            rect.left > window.innerWidth + viewportExpansion))
      ) {
        // console.log("Skipping node outside viewport (quick check):", node.tagName, rect);
        if (debugMode) PERF_METRICS.nodeMetrics.skippedNodes++;
        return null;
      }
    }

    // Process element node
    const nodeData = {
      tagName: node.tagName.toLowerCase(),
      attributes: {},
      xpath: getXPathTree(node, true),
      children: [],
    };

    // Get attributes for interactive elements or potential text containers
    if (
      isInteractiveCandidate(node) ||
      node.tagName.toLowerCase() === 'iframe' ||
      node.tagName.toLowerCase() === 'body'
    ) {
      const attributeNames = node.getAttributeNames?.() || [];
      for (const name of attributeNames) {
        nodeData.attributes[name] = node.getAttribute(name);
      }
    }

    let nodeWasHighlighted = false;
    // Perform visibility, interactivity, and highlighting checks
    if (node.nodeType === Node.ELEMENT_NODE) {
      nodeData.isVisible = isElementVisible(node); // isElementVisible uses offsetWidth/Height, which is fine
      if (nodeData.isVisible) {
        nodeData.isTopElement = isTopElement(node);
        if (nodeData.isTopElement) {
          nodeData.isInteractive = isInteractiveElement(node);
          // Call the dedicated highlighting function
          nodeWasHighlighted = handleHighlighting(nodeData, node, parentIframe, isParentHighlighted);
        }
      }
    }

    // Process children, with special handling for iframes and rich text editors
    if (node.tagName) {
      const tagName = node.tagName.toLowerCase();

      // Handle iframes
      if (tagName === 'iframe') {
        try {
          const iframeDoc = node.contentDocument || node.contentWindow?.document;
          if (iframeDoc) {
            for (const child of iframeDoc.childNodes) {
              const domElement = buildDomTree(child, node, false);
              if (domElement) nodeData.children.push(domElement);
            }
          }
        } catch (e) {
          console.warn('Unable to access iframe:', e);
        }
      }
      // Handle rich text editors and contenteditable elements
      else if (
        node.isContentEditable ||
        node.getAttribute('contenteditable') === 'true' ||
        node.id === 'tinymce' ||
        node.classList.contains('mce-content-body') ||
        (tagName === 'body' && node.getAttribute('data-id')?.startsWith('mce_'))
      ) {
        // Process all child nodes to capture formatted text
        for (const child of node.childNodes) {
          const domElement = buildDomTree(child, parentIframe, nodeWasHighlighted);
          if (domElement) nodeData.children.push(domElement);
        }
      } else {
        // Handle shadow DOM
        if (node.shadowRoot) {
          nodeData.shadowRoot = true;
          for (const child of node.shadowRoot.childNodes) {
            const domElement = buildDomTree(child, parentIframe, nodeWasHighlighted);
            if (domElement) nodeData.children.push(domElement);
          }
        }
        // Handle regular elements
        for (const child of node.childNodes) {
          // Pass the highlighted status of the *current* node to its children
          const passHighlightStatusToChild = nodeWasHighlighted || isParentHighlighted;
          const domElement = buildDomTree(child, parentIframe, passHighlightStatusToChild);
          if (domElement) nodeData.children.push(domElement);
        }
      }
    }

    // Skip empty anchor tags
    if (nodeData.tagName === 'a' && nodeData.children.length === 0 && !nodeData.attributes.href) {
      if (debugMode) PERF_METRICS.nodeMetrics.skippedNodes++;
      return null;
    }

    const id = `${ID.current++}`;
    DOM_HASH_MAP[id] = nodeData;
    if (debugMode) PERF_METRICS.nodeMetrics.processedNodes++;
    return id;
  }

  // After all functions are defined, wrap them with performance measurement
  // Remove buildDomTree from here as we measure it separately
  highlightElement = measureTime(highlightElement);
  isInteractiveElement = measureTime(isInteractiveElement);
  isElementVisible = measureTime(isElementVisible);
  isTopElement = measureTime(isTopElement);
  isInExpandedViewport = measureTime(isInExpandedViewport);
  isTextNodeVisible = measureTime(isTextNodeVisible);
  getEffectiveScroll = measureTime(getEffectiveScroll);

  const rootId = buildDomTree(document.body);

  // Clear the cache before starting
  DOM_CACHE.clearCache();

  // Only process metrics in debug mode
  if (debugMode && PERF_METRICS) {
    // Convert timings to seconds and add useful derived metrics
    Object.keys(PERF_METRICS.timings).forEach(key => {
      PERF_METRICS.timings[key] = PERF_METRICS.timings[key] / 1000;
    });

    Object.keys(PERF_METRICS.buildDomTreeBreakdown).forEach(key => {
      if (typeof PERF_METRICS.buildDomTreeBreakdown[key] === 'number') {
        PERF_METRICS.buildDomTreeBreakdown[key] = PERF_METRICS.buildDomTreeBreakdown[key] / 1000;
      }
    });

    // Add some useful derived metrics
    if (PERF_METRICS.buildDomTreeBreakdown.buildDomTreeCalls > 0) {
      PERF_METRICS.buildDomTreeBreakdown.averageTimePerNode =
        PERF_METRICS.buildDomTreeBreakdown.totalTime / PERF_METRICS.buildDomTreeBreakdown.buildDomTreeCalls;
    }

    PERF_METRICS.buildDomTreeBreakdown.timeInChildCalls =
      PERF_METRICS.buildDomTreeBreakdown.totalTime - PERF_METRICS.buildDomTreeBreakdown.totalSelfTime;

    // Add average time per operation to the metrics
    Object.keys(PERF_METRICS.buildDomTreeBreakdown.domOperations).forEach(op => {
      const time = PERF_METRICS.buildDomTreeBreakdown.domOperations[op];
      const count = PERF_METRICS.buildDomTreeBreakdown.domOperationCounts[op];
      if (count > 0) {
        PERF_METRICS.buildDomTreeBreakdown.domOperations[`${op}Average`] = time / count;
      }
    });

    // Calculate cache hit rates
    const boundingRectTotal =
      PERF_METRICS.cacheMetrics.boundingRectCacheHits + PERF_METRICS.cacheMetrics.boundingRectCacheMisses;
    const computedStyleTotal =
      PERF_METRICS.cacheMetrics.computedStyleCacheHits + PERF_METRICS.cacheMetrics.computedStyleCacheMisses;

    if (boundingRectTotal > 0) {
      PERF_METRICS.cacheMetrics.boundingRectHitRate =
        PERF_METRICS.cacheMetrics.boundingRectCacheHits / boundingRectTotal;
    }

    if (computedStyleTotal > 0) {
      PERF_METRICS.cacheMetrics.computedStyleHitRate =
        PERF_METRICS.cacheMetrics.computedStyleCacheHits / computedStyleTotal;
    }

    if (boundingRectTotal + computedStyleTotal > 0) {
      PERF_METRICS.cacheMetrics.overallHitRate =
        (PERF_METRICS.cacheMetrics.boundingRectCacheHits + PERF_METRICS.cacheMetrics.computedStyleCacheHits) /
        (boundingRectTotal + computedStyleTotal);
    }
  }

  return debugMode ? { rootId, map: DOM_HASH_MAP, perfMetrics: PERF_METRICS } : { rootId, map: DOM_HASH_MAP };
};