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: #include "nsXULTemplateResultSetRDF.h"
michael@0: #include "nsXULTemplateQueryProcessorRDF.h"
michael@0: 
michael@0: NS_IMPL_ISUPPORTS(nsXULTemplateResultSetRDF, nsISimpleEnumerator)
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsXULTemplateResultSetRDF::HasMoreElements(bool *aResult)
michael@0: {
michael@0:     *aResult = true;
michael@0: 
michael@0:     nsCOMPtr<nsIRDFNode> node;
michael@0: 
michael@0:     if (! mInstantiations || ! mQuery) {
michael@0:         *aResult = false;
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0:     if (mCheckedNext) {
michael@0:         if (!mCurrent || mCurrent == &(mInstantiations->mHead))
michael@0:             *aResult = false;
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0:     mCheckedNext = true;
michael@0:                 
michael@0:     do {
michael@0:         if (mCurrent) {
michael@0:             mCurrent = mCurrent->mNext;
michael@0:             if (mCurrent == &(mInstantiations->mHead)) {
michael@0:                 *aResult = false;
michael@0:                 return NS_OK;
michael@0:             }
michael@0:         }
michael@0:         else {
michael@0:             *aResult = ! mInstantiations->Empty();
michael@0:             if (*aResult)
michael@0:                 mCurrent = mInstantiations->mHead.mNext;
michael@0:         }
michael@0: 
michael@0:         // get the value of the member variable. If it is not set, skip
michael@0:         // the result and move on to the next result
michael@0:         if (mCurrent) {
michael@0:             mCurrent->mInstantiation.mAssignments.
michael@0:                 GetAssignmentFor(mQuery->mMemberVariable, getter_AddRefs(node));
michael@0:         }
michael@0: 
michael@0:         // only resources may be used as results
michael@0:         mResource = do_QueryInterface(node);
michael@0:     } while (! mResource);
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsXULTemplateResultSetRDF::GetNext(nsISupports **aResult)
michael@0: {
michael@0:     if (!aResult)
michael@0:         return NS_ERROR_NULL_POINTER;
michael@0: 
michael@0:     if (!mCurrent || !mCheckedNext)
michael@0:         return NS_ERROR_FAILURE;
michael@0: 
michael@0:     nsRefPtr<nsXULTemplateResultRDF> nextresult =
michael@0:         new nsXULTemplateResultRDF(mQuery, mCurrent->mInstantiation, mResource);
michael@0:     if (!nextresult)
michael@0:         return NS_ERROR_OUT_OF_MEMORY;
michael@0: 
michael@0:     // add the supporting memory elements to the processor's map. These are
michael@0:     // used to remove the results when an assertion is removed from the graph
michael@0:     mProcessor->AddMemoryElements(mCurrent->mInstantiation, nextresult);
michael@0: 
michael@0:     mCheckedNext = false;
michael@0: 
michael@0:     *aResult = nextresult;
michael@0:     NS_ADDREF(*aResult);
michael@0: 
michael@0:     return NS_OK;
michael@0: }