/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_a11y_EmbeddedObjCollector_h__

#define mozilla_a11y_EmbeddedObjCollector_h__

#include "nsTArray.h"

namespace mozilla {

namespace a11y {

class Accessible;

/**

 * Collect embedded objects. Provide quick access to accessible by index and

 * vice versa.

 */

class EmbeddedObjCollector final

{

public:

  ~EmbeddedObjCollector() { }

  /**

   * Return index of the given accessible within the collection.

   */

  int32_t GetIndexAt(Accessible* aAccessible);

  /**

   * Return accessible count within the collection.

   */

  uint32_t Count();

  /**

   * Return an accessible from the collection at the given index.

   */

  Accessible* GetAccessibleAt(uint32_t aIndex);

protected:

  /**

   * Ensure accessible at the given index is stored and return it.

   */

  Accessible* EnsureNGetObject(uint32_t aIndex);

  /**

   * Ensure index for the given accessible is stored and return it.

   */

  int32_t EnsureNGetIndex(Accessible* aAccessible);

  // Make sure it's used by Accessible class only.

  explicit EmbeddedObjCollector(Accessible* aRoot) :

    mRoot(aRoot), mRootChildIdx(0) {}

  /**

   * Append the object to collection.

   */

  void AppendObject(Accessible* aAccessible);

  friend class Accessible;

  Accessible* mRoot;

  uint32_t mRootChildIdx;

  nsTArray<Accessible*> mObjects;

};

} // namespace a11y

} // namespace mozilla

#endif