// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_VIEWS_ACCESSIBILITY_VIEW_ACCESSIBILITY_UTILS_H_
#define UI_VIEWS_ACCESSIBILITY_VIEW_ACCESSIBILITY_UTILS_H_


#include "ui/accessibility/ax_enums.mojom-forward.h"
#include "ui/accessibility/ax_node_data.h"
#include "ui/views/view.h"
#include "ui/views/widget/widget.h"

namespace views {

class VIEWS_EXPORT ViewAccessibilityUtils {
 public:
  // Returns a focused child widget if the view has a child that should be
  // treated as a special case. For example, if a tab modal dialog is visible
  // and focused, this will return the dialog when called on the BrowserView.
  // This helper function is used to treat such widgets as separate windows for
  // accessibility. Returns nullptr if no such widget is present.
  static Widget* GetFocusedChildWidgetForAccessibility(const View* view);

  // Used by GetFocusedChildWidgetForAccessibility to determine if a Widget
  // should be handled separately.
  static bool IsFocusedChildWidget(Widget* widget, const View* focused_view);

  // Copies the accessible attributes from `source` to `destination`. If
  // attributes are set in both, the ones in source takes precedence.
  static void Merge(const ui::AXNodeData& source, ui::AXNodeData& destination);

  // Iterates through the attributes set in `a` and validates they are not in
  // `b`. This function acts as a guardrail to prevent Views authors from
  // setting attributes both in the cache before it gets fully initialized and
  // during the initialization step, through the
  // `View::OnAccessibilityInitializing` function.
  //
  // Because this is a performance-intensive debugging check, call sites MUST
  // be wrapped in a `DCHECK_IS_ON()` block to ensure it has no impact on
  // release builds.
  static void ValidateAttributesNotSet(const ui::AXNodeData& new_data,
                                       const ui::AXNodeData& existing_data);
};

}  // namespace views

#endif  // UI_VIEWS_ACCESSIBILITY_VIEW_ACCESSIBILITY_UTILS_H_