michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* vim: set ts=4 et sw=4 tw=80: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0:  
michael@0: /*
michael@0:  * Implementation of DOM Traversal's nsIDOMTreeWalker
michael@0:  */
michael@0: 
michael@0: #ifndef mozilla_dom_TreeWalker_h
michael@0: #define mozilla_dom_TreeWalker_h
michael@0: 
michael@0: #include "nsIDOMTreeWalker.h"
michael@0: #include "nsTraversal.h"
michael@0: #include "nsCOMPtr.h"
michael@0: #include "nsTArray.h"
michael@0: #include "nsCycleCollectionParticipant.h"
michael@0: 
michael@0: class nsINode;
michael@0: class nsIDOMNode;
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace dom {
michael@0: 
michael@0: class TreeWalker MOZ_FINAL : public nsIDOMTreeWalker, public nsTraversal
michael@0: {
michael@0: public:
michael@0:     NS_DECL_CYCLE_COLLECTING_ISUPPORTS
michael@0:     NS_DECL_NSIDOMTREEWALKER
michael@0: 
michael@0:     TreeWalker(nsINode *aRoot,
michael@0:                uint32_t aWhatToShow,
michael@0:                const NodeFilterHolder &aFilter);
michael@0:     virtual ~TreeWalker();
michael@0: 
michael@0:     NS_DECL_CYCLE_COLLECTION_CLASS(TreeWalker)
michael@0: 
michael@0:     // WebIDL API
michael@0:     nsINode* Root() const
michael@0:     {
michael@0:         return mRoot;
michael@0:     }
michael@0:     uint32_t WhatToShow() const
michael@0:     {
michael@0:         return mWhatToShow;
michael@0:     }
michael@0:     already_AddRefed<NodeFilter> GetFilter()
michael@0:     {
michael@0:         return mFilter.ToWebIDLCallback();
michael@0:     }
michael@0:     nsINode* CurrentNode() const
michael@0:     {
michael@0:         return mCurrentNode;
michael@0:     }
michael@0:     void SetCurrentNode(nsINode& aNode, ErrorResult& aResult);
michael@0:     // All our traversal methods return strong refs because filtering can
michael@0:     // remove nodes from the tree.
michael@0:     already_AddRefed<nsINode> ParentNode(ErrorResult& aResult);
michael@0:     already_AddRefed<nsINode> FirstChild(ErrorResult& aResult);
michael@0:     already_AddRefed<nsINode> LastChild(ErrorResult& aResult);
michael@0:     already_AddRefed<nsINode> PreviousSibling(ErrorResult& aResult);
michael@0:     already_AddRefed<nsINode> NextSibling(ErrorResult& aResult);
michael@0:     already_AddRefed<nsINode> PreviousNode(ErrorResult& aResult);
michael@0:     already_AddRefed<nsINode> NextNode(ErrorResult& aResult);
michael@0: 
michael@0:     JSObject* WrapObject(JSContext *cx);
michael@0: 
michael@0: private:
michael@0:     nsCOMPtr<nsINode> mCurrentNode;
michael@0: 
michael@0:     /*
michael@0:      * Implements FirstChild and LastChild which only vary in which direction
michael@0:      * they search.
michael@0:      * @param aReversed Controls whether we search forwards or backwards
michael@0:      * @param aResult   Whether we threw or not.
michael@0:      * @returns         The desired node. Null if no child is found
michael@0:      */
michael@0:     already_AddRefed<nsINode> FirstChildInternal(bool aReversed,
michael@0:                                                  ErrorResult& aResult);
michael@0: 
michael@0:     /*
michael@0:      * Implements NextSibling and PreviousSibling which only vary in which
michael@0:      * direction they search.
michael@0:      * @param aReversed Controls whether we search forwards or backwards
michael@0:      * @param aResult   Whether we threw or not.
michael@0:      * @returns         The desired node. Null if no child is found
michael@0:      */
michael@0:     already_AddRefed<nsINode> NextSiblingInternal(bool aReversed,
michael@0:                                                   ErrorResult& aResult);
michael@0: 
michael@0:     // Implementation for our various XPCOM getters
michael@0:     typedef already_AddRefed<nsINode> (TreeWalker::*NodeGetter)(ErrorResult&);
michael@0:     inline nsresult ImplNodeGetter(NodeGetter aGetter, nsIDOMNode** aRetval)
michael@0:     {
michael@0:         mozilla::ErrorResult rv;
michael@0:         nsCOMPtr<nsINode> node = (this->*aGetter)(rv);
michael@0:         if (rv.Failed()) {
michael@0:             return rv.ErrorCode();
michael@0:         }
michael@0:         *aRetval = node ? node.forget().take()->AsDOMNode() : nullptr;
michael@0:         return NS_OK;
michael@0:     }
michael@0: };
michael@0: 
michael@0: } // namespace dom
michael@0: } // namespace mozilla
michael@0: 
michael@0: #endif // mozilla_dom_TreeWalker_h
michael@0: