michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
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 an XPath NodeSet
michael@0:  */
michael@0: 
michael@0: #ifndef txNodeSet_h__
michael@0: #define txNodeSet_h__
michael@0: 
michael@0: #include "txExprResult.h"
michael@0: #include "nsError.h"
michael@0: #include "txXPathNode.h"
michael@0: 
michael@0: class txNodeSet : public txAExprResult
michael@0: {
michael@0: public:
michael@0:     /**
michael@0:      * Creates a new empty NodeSet
michael@0:      */
michael@0:     txNodeSet(txResultRecycler* aRecycler);
michael@0: 
michael@0:     /**
michael@0:      * Creates a new NodeSet with one node.
michael@0:      */
michael@0:     txNodeSet(const txXPathNode& aNode, txResultRecycler* aRecycler);
michael@0: 
michael@0:     /**
michael@0:      * Creates a new txNodeSet, copying the node references from the source
michael@0:      * NodeSet.
michael@0:      */
michael@0:     txNodeSet(const txNodeSet& aSource, txResultRecycler* aRecycler);
michael@0: 
michael@0:     /**
michael@0:      * Destructor for txNodeSet, deletes the nodes.
michael@0:      */
michael@0:     virtual ~txNodeSet();
michael@0: 
michael@0:     /**
michael@0:      * Adds the specified txXPathNode to this NodeSet if it is not already
michael@0:      * in this NodeSet. The node is inserted according to document order.
michael@0:      *
michael@0:      * @param  aNode the txXPathNode to add to the NodeSet
michael@0:      * @return errorcode.
michael@0:      */
michael@0:     nsresult add(const txXPathNode& aNode);
michael@0: 
michael@0:     /**
michael@0:      * Adds the nodes in specified NodeSet to this NodeSet. The resulting
michael@0:      * NodeSet is sorted in document order and does not contain any duplicate
michael@0:      * nodes.
michael@0:      *
michael@0:      * @param  aNodes the NodeSet to add, must be in document order.
michael@0:      * @return errorcode.
michael@0:      */
michael@0:     nsresult add(const txNodeSet& aNodes);
michael@0:     nsresult addAndTransfer(txNodeSet* aNodes);
michael@0: 
michael@0:     /**
michael@0:      * Append API
michael@0:      * These functions should be used with care.
michael@0:      * They are intended to be used when the caller assures that the resulting
michael@0:      * NodeSet remains in document order.
michael@0:      * Abuse will break document order, and cause errors in the result.
michael@0:      * These functions are significantly faster than the add API, as no
michael@0:      * order info operations will be performed.
michael@0:      */
michael@0: 
michael@0:     /**
michael@0:      * Appends the specified Node to the end of this NodeSet
michael@0:      * @param  aNode the Node to append to the NodeSet
michael@0:      * @return errorcode.
michael@0:      */
michael@0:     nsresult append(const txXPathNode& aNode);
michael@0: 
michael@0:     /**
michael@0:      * Appends the nodes in the specified NodeSet to the end of this NodeSet
michael@0:      * @param  aNodes the NodeSet to append to the NodeSet
michael@0:      * @return errorcode.
michael@0:      */
michael@0:     nsresult append(const txNodeSet& aNodes);
michael@0: 
michael@0:     /**
michael@0:      * API to implement reverse axes in LocationStep.
michael@0:      *
michael@0:      * Before adding nodes to the nodeset for a reversed axis, call
michael@0:      * setReverse(). This will make the append(aNode) and get() methods treat
michael@0:      * the nodeset as required. Do only call append(aNode), get(), mark()
michael@0:      * and sweep() while the nodeset is reversed.
michael@0:      * Afterwards, call unsetReverse(). The nodes are stored in document
michael@0:      * order internally.
michael@0:      */
michael@0:     void setReverse()
michael@0:     {
michael@0:         mDirection = -1;
michael@0:     }
michael@0:     void unsetReverse()
michael@0:     {
michael@0:         mDirection = 1;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * API to implement predicates in PredicateExpr
michael@0:      *
michael@0:      * mark(aIndex) marks the specified member of the nodeset.
michael@0:      * sweep() clears all members of the nodeset that haven't been
michael@0:      * marked before and clear the mMarks array.
michael@0:      */
michael@0:     nsresult mark(int32_t aIndex);
michael@0:     nsresult sweep();
michael@0: 
michael@0:     /**
michael@0:      * Removes all nodes from this nodeset
michael@0:      */
michael@0:     void clear();
michael@0: 
michael@0:     /**
michael@0:      * Returns the index of the specified Node,
michael@0:      * or -1 if the Node is not contained in the NodeSet
michael@0:      * @param  aNode the Node to get the index for
michael@0:      * @param  aStart index to start searching at
michael@0:      * @return index of specified node or -1 if the node does not exist
michael@0:      */
michael@0:     int32_t indexOf(const txXPathNode& aNode, uint32_t aStart = 0) const;
michael@0: 
michael@0:     /**
michael@0:      * Returns true if the specified Node is contained in the set.
michael@0:      * @param  aNode the Node to search for
michael@0:      * @return true if specified Node is contained in the NodeSet
michael@0:      */
michael@0:     bool contains(const txXPathNode& aNode) const
michael@0:     {
michael@0:         return indexOf(aNode) >= 0;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Returns the Node at the specified node in this NodeSet.
michael@0:      * @param  aIndex the node of the Node to return
michael@0:      * @return Node at specified node
michael@0:      */
michael@0:     const txXPathNode& get(int32_t aIndex) const;
michael@0: 
michael@0:     /**
michael@0:      * Returns true if there are no Nodes in the NodeSet.
michael@0:      * @return true if there are no Nodes in the NodeSet.
michael@0:      */
michael@0:     bool isEmpty() const
michael@0:     {
michael@0:         return mStart ? mStart == mEnd : true;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Returns the number of elements in the NodeSet
michael@0:      * @return the number of elements in the NodeSet
michael@0:      */
michael@0:     int32_t size() const
michael@0:     {
michael@0:         return mStart ? mEnd - mStart : 0;
michael@0:     }
michael@0: 
michael@0:     TX_DECL_EXPRRESULT
michael@0: 
michael@0: private:
michael@0:     /**
michael@0:      * Ensure that this nodeset can take another aSize nodes.
michael@0:      *
michael@0:      * Changes mStart and mEnd as well as mBufferStart and mBufferEnd.
michael@0:      */
michael@0:     bool ensureGrowSize(int32_t aSize);
michael@0: 
michael@0:     /**
michael@0:      * Finds position in the buffer where a node should be inserted
michael@0:      * to keep the nodeset in document order. Searches the positions
michael@0:      * aFirst-aLast, including aFirst, but not aLast.
michael@0:      * @param  aNode   Node to find insert position for.
michael@0:      * @param  aFirst  First item of the search range, included.
michael@0:      * @param  aLast   Last item of the search range, excluded.
michael@0:      * @param  aDupe   out-param. Will be set to true if the node already
michael@0:      *                 exists in the NodeSet, false if it should be
michael@0:      *                 inserted.
michael@0:      * @return pointer where to insert the node. The node should be inserted
michael@0:      *         before the given node. This value is always set, even if aNode
michael@0:      *         already exists in the NodeSet
michael@0:      */
michael@0:     txXPathNode* findPosition(const txXPathNode& aNode, 
michael@0:                               txXPathNode* aFirst,
michael@0:                               txXPathNode* aLast, bool& aDupe) const;
michael@0: 
michael@0:     static void copyElements(txXPathNode* aDest, const txXPathNode* aStart,
michael@0:                              const txXPathNode* aEnd);
michael@0:     static void transferElements(txXPathNode* aDest, const txXPathNode* aStart,
michael@0:                                  const txXPathNode* aEnd);
michael@0:     static void destroyElements(const txXPathNode* aStart,
michael@0:                                 const txXPathNode* aEnd)
michael@0:     {
michael@0:         while (aStart < aEnd) {
michael@0:             aStart->~txXPathNode();
michael@0:             ++aStart;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     typedef void (*transferOp) (txXPathNode* aDest, const txXPathNode* aStart,
michael@0:                                 const txXPathNode* aEnd);
michael@0:     typedef void (*destroyOp) (const txXPathNode* aStart,
michael@0:                                const txXPathNode* aEnd);
michael@0:     nsresult add(const txNodeSet& aNodes, transferOp aTransfer,
michael@0:                  destroyOp aDestroy);
michael@0: 
michael@0:     txXPathNode *mStart, *mEnd, *mStartBuffer, *mEndBuffer;
michael@0:     int32_t mDirection;
michael@0:     // used for mark() and sweep() in predicates
michael@0:     bool* mMarks;
michael@0: };
michael@0: 
michael@0: #endif