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: #ifndef nsRDFQuery_h__
michael@0: #define nsRDFQuery_h__
michael@0: 
michael@0: #include "nsAutoPtr.h"
michael@0: #include "nsISimpleEnumerator.h"
michael@0: #include "nsCycleCollectionParticipant.h"
michael@0: #include "mozilla/Attributes.h"
michael@0: 
michael@0: #define NS_ITEMPLATERDFQUERY_IID \
michael@0:   {0x8929ff60, 0x1c9c, 0x4d87, \
michael@0:     { 0xac, 0x02, 0x09, 0x14, 0x15, 0x3b, 0x48, 0xc4 }}
michael@0: 
michael@0: /**
michael@0:  * A compiled query in the RDF query processor. This interface should not be
michael@0:  * used directly outside of the RDF query processor.
michael@0:  */
michael@0: class nsITemplateRDFQuery : public nsISupports
michael@0: {
michael@0: public:
michael@0:     NS_DECLARE_STATIC_IID_ACCESSOR(NS_ITEMPLATERDFQUERY_IID)
michael@0: 
michael@0:     // return the processor the query was created from
michael@0:     virtual nsXULTemplateQueryProcessorRDF* Processor() = 0;  // not addrefed
michael@0: 
michael@0:     // return the member variable for the query
michael@0:     virtual nsIAtom* GetMemberVariable() = 0; // not addrefed
michael@0: 
michael@0:     // return the <query> node the query was compiled from
michael@0:     virtual void GetQueryNode(nsIDOMNode** aQueryNode) = 0;
michael@0: 
michael@0:     // remove any results that are cached by the query
michael@0:     virtual void ClearCachedResults() = 0;
michael@0: };
michael@0: 
michael@0: class nsRDFQuery MOZ_FINAL : public nsITemplateRDFQuery
michael@0: {
michael@0: public:
michael@0: 
michael@0:     nsRDFQuery(nsXULTemplateQueryProcessorRDF* aProcessor)
michael@0:       : mProcessor(aProcessor),
michael@0:         mSimple(false),
michael@0:         mRoot(nullptr),
michael@0:         mCachedResults(nullptr)
michael@0:     { }
michael@0: 
michael@0:     ~nsRDFQuery() { Finish(); }
michael@0: 
michael@0:     NS_DECL_CYCLE_COLLECTING_ISUPPORTS
michael@0:     NS_DECL_CYCLE_COLLECTION_CLASS(nsRDFQuery)
michael@0: 
michael@0:     /**
michael@0:      * Retrieve the root node in the rule network
michael@0:      * @return the root node in the rule network
michael@0:      */
michael@0:     TestNode* GetRoot() { return mRoot; }
michael@0: 
michael@0:     void SetRoot(TestNode* aRoot) { mRoot = aRoot; }
michael@0: 
michael@0:     void GetQueryNode(nsIDOMNode** aQueryNode) MOZ_OVERRIDE
michael@0:     {
michael@0:        *aQueryNode = mQueryNode;
michael@0:        NS_IF_ADDREF(*aQueryNode);
michael@0:     }
michael@0: 
michael@0:     void SetQueryNode(nsIDOMNode* aQueryNode)
michael@0:     {
michael@0:        mQueryNode = aQueryNode;
michael@0:     }
michael@0: 
michael@0:     // an optimization is used when several queries all use the simple query
michael@0:     // syntax. Since simple queries can only generate one possible set of
michael@0:     // results, they only need to be calculated once and reused for every
michael@0:     // simple query. The results may be cached in the query for this purpose.
michael@0:     // If successful, this method takes ownership of aInstantiations.
michael@0:     nsresult SetCachedResults(nsXULTemplateQueryProcessorRDF* aProcessor,
michael@0:                               const InstantiationSet& aInstantiations);
michael@0: 
michael@0:     // grab the cached results, if any, causing the caller to take ownership
michael@0:     // of them. This also has the effect of setting the cached results in this
michael@0:     // nsRDFQuery to null.
michael@0:     void UseCachedResults(nsISimpleEnumerator** aResults);
michael@0: 
michael@0:     // clear the cached results
michael@0:     void ClearCachedResults() MOZ_OVERRIDE
michael@0:     {
michael@0:         mCachedResults = nullptr;
michael@0:     }
michael@0: 
michael@0:     nsXULTemplateQueryProcessorRDF* Processor() MOZ_OVERRIDE { return mProcessor; }
michael@0: 
michael@0:     nsIAtom* GetMemberVariable() MOZ_OVERRIDE { return mMemberVariable; }
michael@0: 
michael@0:     bool IsSimple() { return mSimple; }
michael@0: 
michael@0:     void SetSimple() { mSimple = true; }
michael@0: 
michael@0:     // the reference and member variables for the query
michael@0:     nsCOMPtr<nsIAtom> mRefVariable;
michael@0:     nsCOMPtr<nsIAtom> mMemberVariable;
michael@0: 
michael@0: protected:
michael@0: 
michael@0:     nsXULTemplateQueryProcessorRDF* mProcessor;
michael@0: 
michael@0:     // true if the query is a simple rule (one with a default query)
michael@0:     bool mSimple;
michael@0: 
michael@0:     /**
michael@0:      * The root node in the network for this query
michael@0:      */
michael@0:     TestNode *mRoot;
michael@0: 
michael@0:     // the <query> node
michael@0:     nsCOMPtr<nsIDOMNode> mQueryNode;
michael@0: 
michael@0:     // used for simple rules since their results are all determined in one step
michael@0:     nsCOMPtr<nsISimpleEnumerator> mCachedResults;
michael@0: 
michael@0:     void Finish();
michael@0: };
michael@0: 
michael@0: NS_DEFINE_STATIC_IID_ACCESSOR(nsITemplateRDFQuery, NS_ITEMPLATERDFQUERY_IID)
michael@0: 
michael@0: #endif // nsRDFQuery_h__