/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* 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 nsDocShellEnumerator_h___

#define nsDocShellEnumerator_h___

#include "nsSimpleEnumerator.h"

#include "nsTArray.h"

#include "nsIWeakReferenceUtils.h"

class nsIDocShellTreeItem;

/*

// {13cbc281-35ae-11d5-be5b-bde0edece43c}

#define NS_DOCSHELL_FORWARDS_ENUMERATOR_CID  \

{ 0x13cbc281, 0x35ae, 0x11d5, { 0xbe, 0x5b, 0xbd, 0xe0, 0xed, 0xec, 0xe4, 0x3c } }

#define NS_DOCSHELL_FORWARDS_ENUMERATOR_CONTRACTID \

"@mozilla.org/docshell/enumerator-forwards;1"

// {13cbc282-35ae-11d5-be5b-bde0edece43c}

#define NS_DOCSHELL_BACKWARDS_ENUMERATOR_CID  \

{ 0x13cbc282, 0x35ae, 0x11d5, { 0xbe, 0x5b, 0xbd, 0xe0, 0xed, 0xec, 0xe4, 0x3c } }

#define NS_DOCSHELL_BACKWARDS_ENUMERATOR_CONTRACTID \

"@mozilla.org/docshell/enumerator-backwards;1"

*/

class nsDocShellEnumerator : public nsSimpleEnumerator

{

protected:

  enum

  {

    enumerateForwards,

    enumerateBackwards

  };

  virtual ~nsDocShellEnumerator();

public:

  explicit nsDocShellEnumerator(int32_t aEnumerationDirection);

  // nsISimpleEnumerator

  NS_DECL_NSISIMPLEENUMERATOR

  const nsID& DefaultInterface() override { return NS_GET_IID(nsIDocShell); }

public:

  nsresult GetEnumerationRootItem(nsIDocShellTreeItem** aEnumerationRootItem);

  nsresult SetEnumerationRootItem(nsIDocShellTreeItem* aEnumerationRootItem);

  nsresult GetEnumDocShellType(int32_t* aEnumerationItemType);

  nsresult SetEnumDocShellType(int32_t aEnumerationItemType);

  nsresult First();

protected:

  nsresult EnsureDocShellArray();

  nsresult ClearState();

  nsresult BuildDocShellArray(nsTArray<nsWeakPtr>& aItemArray);

  virtual nsresult BuildArrayRecursive(nsIDocShellTreeItem* aItem,

                                       nsTArray<nsWeakPtr>& aItemArray) = 0;

protected:

  nsWeakPtr mRootItem;  // weak ref!

  nsTArray<nsWeakPtr> mItemArray;  // flattened list of items with matching type

  uint32_t mCurIndex;

  int32_t mDocShellType;  // only want shells of this type

  bool mArrayValid;  // is mItemArray up to date?

  const int8_t mEnumerationDirection;

};

class nsDocShellForwardsEnumerator : public nsDocShellEnumerator

{

public:

  nsDocShellForwardsEnumerator()

    : nsDocShellEnumerator(enumerateForwards)

  {

  }

protected:

  virtual nsresult BuildArrayRecursive(nsIDocShellTreeItem* aItem,

                                       nsTArray<nsWeakPtr>& aItemArray) override;

};

class nsDocShellBackwardsEnumerator : public nsDocShellEnumerator

{

public:

  nsDocShellBackwardsEnumerator()

    : nsDocShellEnumerator(enumerateBackwards)

  {

  }

protected:

  virtual nsresult BuildArrayRecursive(nsIDocShellTreeItem* aItem,

                                       nsTArray<nsWeakPtr>& aItemArray) override;

};

#endif // nsDocShellEnumerator_h___