/* -*- 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 __nsIContentIterator_h___
#define __nsIContentIterator_h___

#include "nsISupports.h"
#include "nsCOMPtr.h"
#include "mozilla/RangeBoundary.h"

class nsINode;
class nsIDOMRange;

#define NS_ICONTENTITERATOR_IID                      \
  {                                                  \
    0x2550078e, 0xae87, 0x4914, {                    \
      0xb3, 0x04, 0xe4, 0xd1, 0x46, 0x19, 0x3d, 0x5f \
    }                                                \
  }

class nsIContentIterator : public nsISupports {
 public:
  NS_DECLARE_STATIC_IID_ACCESSOR(NS_ICONTENTITERATOR_IID)

  /* Initializes an iterator for the subtree rooted by the node aRoot
   */
  virtual nsresult Init(nsINode* aRoot) = 0;

  /* Initializes an iterator for the subtree defined by the range aRange
     Subclasses should make sure they implement both of these!
   */
  virtual nsresult Init(nsIDOMRange* aRange) = 0;

  /* Initializes an iterator for the subtree between
     aStartContainer/aStartOffset and aEndContainer/aEndOffset
     Callers should guarantee that the start point and end point are in
     document order.
   */
  virtual nsresult Init(nsINode* aStartContainer, uint32_t aStartOffset,
                        nsINode* aEndContainer, uint32_t aEndOffset) = 0;

  /* Initializes an iterator for the subtree between aStart and aEnd.
     Callers should guarantee that the start point and end point are in
     document order.
   */
  virtual nsresult Init(const mozilla::RawRangeBoundary& aStart,
                        const mozilla::RawRangeBoundary& aEnd) = 0;

  /** First will reset the list.
   */
  virtual void First() = 0;

  /** Last will reset the list to the end.
   */
  virtual void Last() = 0;

  /** Next will advance the list.
   */
  virtual void Next() = 0;

  /** Prev will decrement the list.
   */
  virtual void Prev() = 0;

  /** CurrentItem will return the current item, or null if the list is empty
   *  @return the current node
   */
  virtual nsINode* GetCurrentNode() = 0;

  /** return if the collection is at the end. that is the beginning following a
   * call to Prev and it is the end of the list following a call to next
   *  @return if the iterator is done.
   */
  virtual bool IsDone() = 0;

  /** PositionAt will position the iterator to the supplied node
   */
  virtual nsresult PositionAt(nsINode* aCurNode) = 0;
};

NS_DEFINE_STATIC_IID_ACCESSOR(nsIContentIterator, NS_ICONTENTITERATOR_IID)

already_AddRefed<nsIContentIterator> NS_NewContentIterator();
already_AddRefed<nsIContentIterator> NS_NewPreContentIterator();
already_AddRefed<nsIContentIterator> NS_NewContentSubtreeIterator();

#endif  // __nsIContentIterator_h___