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: 
michael@0:   Implementation for the RDF container.
michael@0: 
michael@0:   Notes
michael@0:   -----
michael@0: 
michael@0:   1. RDF containers are one-indexed. This means that a lot of the loops
michael@0:      that you'd normally think you'd write like this:
michael@0: 
michael@0:        for (i = 0; i < count; ++i) {}
michael@0: 
michael@0:      You've gotta write like this:
michael@0: 
michael@0:        for (i = 1; i <= count; ++i) {}
michael@0: 
michael@0:      "Sure, right, yeah, of course.", you say. Well maybe I'm just
michael@0:      thick, but it's easy to slip up.
michael@0: 
michael@0:   2. The RDF:nextVal property on the container is an
michael@0:      implementation-level hack that is used to quickly compute the
michael@0:      next value for appending to the container. It will no doubt
michael@0:      become royally screwed up in the case of aggregation.
michael@0: 
michael@0:   3. The RDF:nextVal property is also used to retrieve the count of
michael@0:      elements in the container.
michael@0: 
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include "nsCOMPtr.h"
michael@0: #include "nsIRDFContainer.h"
michael@0: #include "nsIRDFContainerUtils.h"
michael@0: #include "nsIRDFInMemoryDataSource.h"
michael@0: #include "nsIRDFPropagatableDataSource.h"
michael@0: #include "nsIRDFService.h"
michael@0: #include "nsIServiceManager.h"
michael@0: #include "nsRDFCID.h"
michael@0: #include "nsString.h"
michael@0: #include "nsXPIDLString.h"
michael@0: #include "rdf.h"
michael@0: 
michael@0: #define RDF_SEQ_LIST_LIMIT   8
michael@0: 
michael@0: class RDFContainerImpl : public nsIRDFContainer
michael@0: {
michael@0: public:
michael@0: 
michael@0:     // nsISupports interface
michael@0:     NS_DECL_ISUPPORTS
michael@0: 
michael@0:     // nsIRDFContainer interface
michael@0:     NS_DECL_NSIRDFCONTAINER
michael@0: 
michael@0: private:
michael@0:     friend nsresult NS_NewRDFContainer(nsIRDFContainer** aResult);
michael@0: 
michael@0:     RDFContainerImpl();
michael@0:     virtual ~RDFContainerImpl();
michael@0: 
michael@0:     nsresult Init();
michael@0: 
michael@0:     nsresult Renumber(int32_t aStartIndex, int32_t aIncrement);
michael@0:     nsresult SetNextValue(int32_t aIndex);
michael@0:     nsresult GetNextValue(nsIRDFResource** aResult);
michael@0:     
michael@0:     nsIRDFDataSource* mDataSource;
michael@0:     nsIRDFResource*   mContainer;
michael@0: 
michael@0:     // pseudo constants
michael@0:     static int32_t gRefCnt;
michael@0:     static nsIRDFService*        gRDFService;
michael@0:     static nsIRDFContainerUtils* gRDFContainerUtils;
michael@0:     static nsIRDFResource*       kRDF_nextVal;
michael@0: };
michael@0: 
michael@0: 
michael@0: int32_t               RDFContainerImpl::gRefCnt = 0;
michael@0: nsIRDFService*        RDFContainerImpl::gRDFService;
michael@0: nsIRDFContainerUtils* RDFContainerImpl::gRDFContainerUtils;
michael@0: nsIRDFResource*       RDFContainerImpl::kRDF_nextVal;
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////
michael@0: // nsISupports interface
michael@0: 
michael@0: NS_IMPL_ISUPPORTS(RDFContainerImpl, nsIRDFContainer)
michael@0: 
michael@0: 
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////
michael@0: // nsIRDFContainer interface
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: RDFContainerImpl::GetDataSource(nsIRDFDataSource** _retval)
michael@0: {
michael@0:     *_retval = mDataSource;
michael@0:     NS_IF_ADDREF(*_retval);
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: RDFContainerImpl::GetResource(nsIRDFResource** _retval)
michael@0: {
michael@0:     *_retval = mContainer;
michael@0:     NS_IF_ADDREF(*_retval);
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: RDFContainerImpl::Init(nsIRDFDataSource *aDataSource, nsIRDFResource *aContainer)
michael@0: {
michael@0:     NS_PRECONDITION(aDataSource != nullptr, "null ptr");
michael@0:     if (! aDataSource)
michael@0:         return NS_ERROR_NULL_POINTER;
michael@0: 
michael@0:     NS_PRECONDITION(aContainer != nullptr, "null ptr");
michael@0:     if (! aContainer)
michael@0:         return NS_ERROR_NULL_POINTER;
michael@0: 
michael@0:     nsresult rv;
michael@0:     bool isContainer;
michael@0:     rv = gRDFContainerUtils->IsContainer(aDataSource, aContainer, &isContainer);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     // ``throw'' if we can't create a container on the specified
michael@0:     // datasource/resource combination.
michael@0:     if (! isContainer)
michael@0:         return NS_ERROR_FAILURE;
michael@0: 
michael@0:     NS_IF_RELEASE(mDataSource);
michael@0:     mDataSource = aDataSource;
michael@0:     NS_ADDREF(mDataSource);
michael@0: 
michael@0:     NS_IF_RELEASE(mContainer);
michael@0:     mContainer = aContainer;
michael@0:     NS_ADDREF(mContainer);
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: RDFContainerImpl::GetCount(int32_t *aCount)
michael@0: {
michael@0:     if (!mDataSource || !mContainer)
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     nsresult rv;
michael@0: 
michael@0:     // Get the next value, which hangs off of the bag via the
michael@0:     // RDF:nextVal property. This is the _next value_ that will get
michael@0:     // assigned in a one-indexed array. So, it's actually _one more_
michael@0:     // than the actual count of elements in the container.
michael@0:     //
michael@0:     // XXX To handle aggregation, this should probably be a
michael@0:     // GetTargets() that enumerates all of the values and picks the
michael@0:     // largest one.
michael@0:     nsCOMPtr<nsIRDFNode> nextValNode;
michael@0:     rv = mDataSource->GetTarget(mContainer, kRDF_nextVal, true, getter_AddRefs(nextValNode));
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     if (rv == NS_RDF_NO_VALUE)
michael@0:         return NS_ERROR_UNEXPECTED;
michael@0: 
michael@0:     nsCOMPtr<nsIRDFLiteral> nextValLiteral;
michael@0:     rv = nextValNode->QueryInterface(NS_GET_IID(nsIRDFLiteral), getter_AddRefs(nextValLiteral));
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     const char16_t *s;
michael@0:     rv = nextValLiteral->GetValueConst( &s );
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     nsAutoString nextValStr(s);
michael@0: 
michael@0:     int32_t nextVal;
michael@0:     nsresult err;
michael@0:     nextVal = nextValStr.ToInteger(&err);
michael@0:     if (NS_FAILED(err))
michael@0:         return NS_ERROR_UNEXPECTED;
michael@0: 
michael@0:     *aCount = nextVal - 1;
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: RDFContainerImpl::GetElements(nsISimpleEnumerator **_retval)
michael@0: {
michael@0:     if (!mDataSource || !mContainer)
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     return NS_NewContainerEnumerator(mDataSource, mContainer, _retval);
michael@0: }
michael@0: 
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: RDFContainerImpl::AppendElement(nsIRDFNode *aElement)
michael@0: {
michael@0:     if (!mDataSource || !mContainer)
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     NS_PRECONDITION(aElement != nullptr, "null ptr");
michael@0:     if (! aElement)
michael@0:         return NS_ERROR_NULL_POINTER;
michael@0: 
michael@0:     nsresult rv;
michael@0: 
michael@0:     nsCOMPtr<nsIRDFResource> nextVal;
michael@0:     rv = GetNextValue(getter_AddRefs(nextVal));
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     rv = mDataSource->Assert(mContainer, nextVal, aElement, true);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: RDFContainerImpl::RemoveElement(nsIRDFNode *aElement, bool aRenumber)
michael@0: {
michael@0:     if (!mDataSource || !mContainer)
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     NS_PRECONDITION(aElement != nullptr, "null ptr");
michael@0:     if (! aElement)
michael@0:         return NS_ERROR_NULL_POINTER;
michael@0: 
michael@0:     nsresult rv;
michael@0: 
michael@0:     int32_t idx;
michael@0:     rv = IndexOf(aElement, &idx);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     if (idx < 0)
michael@0:         return NS_OK;
michael@0: 
michael@0:     // Remove the element.
michael@0:     nsCOMPtr<nsIRDFResource> ordinal;
michael@0:     rv = gRDFContainerUtils->IndexToOrdinalResource(idx,
michael@0:                                                     getter_AddRefs(ordinal));
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     rv = mDataSource->Unassert(mContainer, ordinal, aElement);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     if (aRenumber) {
michael@0:         // Now slide the rest of the collection backwards to fill in
michael@0:         // the gap. This will have the side effect of completely
michael@0:         // renumber the container from index to the end.
michael@0:         rv = Renumber(idx + 1, -1);
michael@0:         if (NS_FAILED(rv)) return rv;
michael@0:     }
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: RDFContainerImpl::InsertElementAt(nsIRDFNode *aElement, int32_t aIndex, bool aRenumber)
michael@0: {
michael@0:     if (!mDataSource || !mContainer)
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     NS_PRECONDITION(aElement != nullptr, "null ptr");
michael@0:     if (! aElement)
michael@0:         return NS_ERROR_NULL_POINTER;
michael@0: 
michael@0:     NS_PRECONDITION(aIndex >= 1, "illegal value");
michael@0:     if (aIndex < 1)
michael@0:         return NS_ERROR_ILLEGAL_VALUE;
michael@0: 
michael@0:     nsresult rv;
michael@0: 
michael@0:     int32_t count;
michael@0:     rv = GetCount(&count);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     NS_ASSERTION(aIndex <= count + 1, "illegal value");
michael@0:     if (aIndex > count + 1)
michael@0:         return NS_ERROR_ILLEGAL_VALUE;
michael@0: 
michael@0:     if (aRenumber) {
michael@0:         // Make a hole for the element. This will have the side effect of
michael@0:         // completely renumbering the container from 'aIndex' to 'count',
michael@0:         // and will spew assertions.
michael@0:         rv = Renumber(aIndex, +1);
michael@0:         if (NS_FAILED(rv)) return rv;
michael@0:     }
michael@0: 
michael@0:     nsCOMPtr<nsIRDFResource> ordinal;
michael@0:     rv = gRDFContainerUtils->IndexToOrdinalResource(aIndex, getter_AddRefs(ordinal));
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     rv = mDataSource->Assert(mContainer, ordinal, aElement, true);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: RDFContainerImpl::RemoveElementAt(int32_t aIndex, bool aRenumber, nsIRDFNode** _retval)
michael@0: {
michael@0:     if (!mDataSource || !mContainer)
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     *_retval = nullptr;
michael@0: 
michael@0:     if (aIndex< 1)
michael@0:         return NS_ERROR_ILLEGAL_VALUE;
michael@0: 
michael@0:     nsresult rv;
michael@0: 
michael@0:     int32_t count;
michael@0:     rv = GetCount(&count);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     if (aIndex > count)
michael@0:         return NS_ERROR_ILLEGAL_VALUE;
michael@0: 
michael@0:     nsCOMPtr<nsIRDFResource> ordinal;
michael@0:     rv = gRDFContainerUtils->IndexToOrdinalResource(aIndex, getter_AddRefs(ordinal));
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     nsCOMPtr<nsIRDFNode> old;
michael@0:     rv = mDataSource->GetTarget(mContainer, ordinal, true, getter_AddRefs(old));
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     if (rv == NS_OK) {
michael@0:         rv = mDataSource->Unassert(mContainer, ordinal, old);
michael@0:         if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:         if (aRenumber) {
michael@0:             // Now slide the rest of the collection backwards to fill in
michael@0:             // the gap. This will have the side effect of completely
michael@0:             // renumber the container from index to the end.
michael@0:             rv = Renumber(aIndex + 1, -1);
michael@0:             if (NS_FAILED(rv)) return rv;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     old.swap(*_retval);
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: RDFContainerImpl::IndexOf(nsIRDFNode *aElement, int32_t *aIndex)
michael@0: {
michael@0:     if (!mDataSource || !mContainer)
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     return gRDFContainerUtils->IndexOf(mDataSource, mContainer,
michael@0:                                        aElement, aIndex);
michael@0: }
michael@0: 
michael@0: 
michael@0: ////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: 
michael@0: RDFContainerImpl::RDFContainerImpl()
michael@0:     : mDataSource(nullptr), mContainer(nullptr)
michael@0: {
michael@0: }
michael@0: 
michael@0: 
michael@0: nsresult
michael@0: RDFContainerImpl::Init()
michael@0: {
michael@0:     if (gRefCnt++ == 0) {
michael@0:         nsresult rv;
michael@0: 
michael@0:         NS_DEFINE_CID(kRDFServiceCID, NS_RDFSERVICE_CID);
michael@0:         rv = CallGetService(kRDFServiceCID, &gRDFService);
michael@0:         if (NS_FAILED(rv)) {
michael@0:             NS_ERROR("unable to get RDF service");
michael@0:             return rv;
michael@0:         }
michael@0: 
michael@0:         rv = gRDFService->GetResource(NS_LITERAL_CSTRING(RDF_NAMESPACE_URI "nextVal"),
michael@0:                                       &kRDF_nextVal);
michael@0:         if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:         NS_DEFINE_CID(kRDFContainerUtilsCID, NS_RDFCONTAINERUTILS_CID);
michael@0:         rv = CallGetService(kRDFContainerUtilsCID, &gRDFContainerUtils);
michael@0:         if (NS_FAILED(rv)) {
michael@0:             NS_ERROR("unable to get RDF container utils service");
michael@0:             return rv;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: RDFContainerImpl::~RDFContainerImpl()
michael@0: {
michael@0: #ifdef DEBUG_REFS
michael@0:     --gInstanceCount;
michael@0:     fprintf(stdout, "%d - RDF: RDFContainerImpl\n", gInstanceCount);
michael@0: #endif
michael@0: 
michael@0:     NS_IF_RELEASE(mContainer);
michael@0:     NS_IF_RELEASE(mDataSource);
michael@0: 
michael@0:     if (--gRefCnt == 0) {
michael@0:         NS_IF_RELEASE(gRDFContainerUtils);
michael@0:         NS_IF_RELEASE(gRDFService);
michael@0:         NS_IF_RELEASE(kRDF_nextVal);
michael@0:     }
michael@0: }
michael@0: 
michael@0: 
michael@0: nsresult
michael@0: NS_NewRDFContainer(nsIRDFContainer** aResult)
michael@0: {
michael@0:     RDFContainerImpl* result = new RDFContainerImpl();
michael@0:     if (! result)
michael@0:         return NS_ERROR_OUT_OF_MEMORY;
michael@0: 
michael@0:     nsresult rv;
michael@0:     rv = result->Init();
michael@0:     if (NS_FAILED(rv)) {
michael@0:         delete result;
michael@0:         return rv;
michael@0:     }
michael@0: 
michael@0:     NS_ADDREF(result);
michael@0:     *aResult = result;
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: nsresult
michael@0: NS_NewRDFContainer(nsIRDFDataSource* aDataSource,
michael@0:                    nsIRDFResource* aResource,
michael@0:                    nsIRDFContainer** aResult)
michael@0: {
michael@0:     nsresult rv;
michael@0:     rv = NS_NewRDFContainer(aResult);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     rv = (*aResult)->Init(aDataSource, aResource);
michael@0:     if (NS_FAILED(rv)) {
michael@0:         NS_RELEASE(*aResult);
michael@0:     }
michael@0:     return rv;
michael@0: }
michael@0: 
michael@0: 
michael@0: nsresult
michael@0: RDFContainerImpl::Renumber(int32_t aStartIndex, int32_t aIncrement)
michael@0: {
michael@0:     if (!mDataSource || !mContainer)
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     // Renumber the elements in the container starting with
michael@0:     // aStartIndex, updating each element's index by aIncrement. For
michael@0:     // example,
michael@0:     //
michael@0:     //   (1:a 2:b 3:c)
michael@0:     //   Renumber(2, +1);
michael@0:     //   (1:a 3:b 4:c)
michael@0:     //   Renumber(3, -1);
michael@0:     //   (1:a 2:b 3:c)
michael@0:     //
michael@0:     nsresult rv;
michael@0: 
michael@0:     if (! aIncrement)
michael@0:         return NS_OK;
michael@0: 
michael@0:     int32_t count;
michael@0:     rv = GetCount(&count);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     if (aIncrement > 0) {
michael@0:         // Update the container's nextVal to reflect the
michael@0:         // renumbering. We do this now if aIncrement > 0 because we'll
michael@0:         // want to be able to acknowledge that new elements are in the
michael@0:         // container.
michael@0:         rv = SetNextValue(count + aIncrement + 1);
michael@0:         if (NS_FAILED(rv)) return rv;
michael@0:     }
michael@0: 
michael@0:     int32_t i;
michael@0:     if (aIncrement < 0) {
michael@0:         i = aStartIndex;
michael@0:     }
michael@0:     else {
michael@0:         i = count; // we're one-indexed.
michael@0:     }
michael@0: 
michael@0:     // Note: once we disable notifications, don't exit this method until
michael@0:     // enabling notifications
michael@0:     nsCOMPtr<nsIRDFPropagatableDataSource> propagatable =
michael@0:         do_QueryInterface(mDataSource);
michael@0:     if (propagatable) {
michael@0:         propagatable->SetPropagateChanges(false);
michael@0:     }
michael@0: 
michael@0:     bool    err = false;
michael@0:     while (!err && ((aIncrement < 0) ? (i <= count) : (i >= aStartIndex)))
michael@0:     {
michael@0:         nsCOMPtr<nsIRDFResource> oldOrdinal;
michael@0:         rv = gRDFContainerUtils->IndexToOrdinalResource(i, getter_AddRefs(oldOrdinal));
michael@0:         if (NS_FAILED(rv))
michael@0:         {
michael@0:             err = true;
michael@0:             continue;
michael@0:         }
michael@0: 
michael@0:         nsCOMPtr<nsIRDFResource> newOrdinal;
michael@0:         rv = gRDFContainerUtils->IndexToOrdinalResource(i + aIncrement, getter_AddRefs(newOrdinal));
michael@0:         if (NS_FAILED(rv))
michael@0:         {
michael@0:             err = true;
michael@0:             continue;
michael@0:         }
michael@0: 
michael@0:         // Because of aggregation, we need to be paranoid about the
michael@0:         // possibility that >1 element may be present per ordinal. If
michael@0:         // there _is_ in fact more than one element, they'll all get
michael@0:         // assigned to the same new ordinal; i.e., we don't make any
michael@0:         // attempt to "clean up" the duplicate numbering. (Doing so
michael@0:         // would require two passes.)
michael@0:         nsCOMPtr<nsISimpleEnumerator> targets;
michael@0:         rv = mDataSource->GetTargets(mContainer, oldOrdinal, true, getter_AddRefs(targets));
michael@0:         if (NS_FAILED(rv))
michael@0:         {
michael@0:             err = true;
michael@0:             continue;
michael@0:         }
michael@0: 
michael@0:         while (1) {
michael@0:             bool hasMore;
michael@0:             rv = targets->HasMoreElements(&hasMore);
michael@0:             if (NS_FAILED(rv))
michael@0:             {
michael@0:                 err = true;
michael@0:                 break;
michael@0:             }
michael@0: 
michael@0:             if (! hasMore)
michael@0:                 break;
michael@0: 
michael@0:             nsCOMPtr<nsISupports> isupports;
michael@0:             rv = targets->GetNext(getter_AddRefs(isupports));
michael@0:             if (NS_FAILED(rv))
michael@0:             {
michael@0:                 err = true;
michael@0:                 break;
michael@0:             }
michael@0: 
michael@0:             nsCOMPtr<nsIRDFNode> element( do_QueryInterface(isupports) );
michael@0:             NS_ASSERTION(element != nullptr, "something funky in the enumerator");
michael@0:             if (! element)
michael@0:             {
michael@0:                 err = true;
michael@0:                 rv = NS_ERROR_UNEXPECTED;
michael@0:                 break;
michael@0:             }
michael@0: 
michael@0:             rv = mDataSource->Unassert(mContainer, oldOrdinal, element);
michael@0:             if (NS_FAILED(rv))
michael@0:             {
michael@0:                 err = true;
michael@0:                 break;
michael@0:             }
michael@0: 
michael@0:             rv = mDataSource->Assert(mContainer, newOrdinal, element, true);
michael@0:             if (NS_FAILED(rv))
michael@0:             {
michael@0:                 err = true;
michael@0:                 break;
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         i -= aIncrement;
michael@0:     }
michael@0: 
michael@0:     if (!err && (aIncrement < 0))
michael@0:     {
michael@0:         // Update the container's nextVal to reflect the
michael@0:         // renumbering. We do this now if aIncrement < 0 because, up
michael@0:         // until this point, we'll want people to be able to find
michael@0:         // things that are still "at the end".
michael@0:         rv = SetNextValue(count + aIncrement + 1);
michael@0:         if (NS_FAILED(rv))
michael@0:         {
michael@0:             err = true;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     // Note: MUST enable notifications before exiting this method
michael@0:     if (propagatable) {
michael@0:         propagatable->SetPropagateChanges(true);
michael@0:     }
michael@0: 
michael@0:     if (err) return(rv);
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: 
michael@0: nsresult
michael@0: RDFContainerImpl::SetNextValue(int32_t aIndex)
michael@0: {
michael@0:     if (!mDataSource || !mContainer)
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     nsresult rv;
michael@0: 
michael@0:     // Remove the current value of nextVal, if there is one.
michael@0:     nsCOMPtr<nsIRDFNode> nextValNode;
michael@0:     if (NS_SUCCEEDED(rv = mDataSource->GetTarget(mContainer,
michael@0:                                                  kRDF_nextVal,
michael@0:                                                  true,
michael@0:                                                  getter_AddRefs(nextValNode)))) {
michael@0:         if (NS_FAILED(rv = mDataSource->Unassert(mContainer, kRDF_nextVal, nextValNode))) {
michael@0:             NS_ERROR("unable to update nextVal");
michael@0:             return rv;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     nsAutoString s;
michael@0:     s.AppendInt(aIndex, 10);
michael@0: 
michael@0:     nsCOMPtr<nsIRDFLiteral> nextVal;
michael@0:     if (NS_FAILED(rv = gRDFService->GetLiteral(s.get(), getter_AddRefs(nextVal)))) {
michael@0:         NS_ERROR("unable to get nextVal literal");
michael@0:         return rv;
michael@0:     }
michael@0: 
michael@0:     rv = mDataSource->Assert(mContainer, kRDF_nextVal, nextVal, true);
michael@0:     if (rv != NS_RDF_ASSERTION_ACCEPTED) {
michael@0:         NS_ERROR("unable to update nextVal");
michael@0:         return NS_ERROR_FAILURE;
michael@0:     }
michael@0: 
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: nsresult
michael@0: RDFContainerImpl::GetNextValue(nsIRDFResource** aResult)
michael@0: {
michael@0:     if (!mDataSource || !mContainer)
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     nsresult rv;
michael@0: 
michael@0:     // Get the next value, which hangs off of the bag via the
michael@0:     // RDF:nextVal property.
michael@0:     nsCOMPtr<nsIRDFNode> nextValNode;
michael@0:     rv = mDataSource->GetTarget(mContainer, kRDF_nextVal, true, getter_AddRefs(nextValNode));
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     if (rv == NS_RDF_NO_VALUE)
michael@0:         return NS_ERROR_UNEXPECTED;
michael@0: 
michael@0:     nsCOMPtr<nsIRDFLiteral> nextValLiteral;
michael@0:     rv = nextValNode->QueryInterface(NS_GET_IID(nsIRDFLiteral), getter_AddRefs(nextValLiteral));
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     const char16_t* s;
michael@0:     rv = nextValLiteral->GetValueConst(&s);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     int32_t nextVal = 0;
michael@0:     {
michael@0:         for (const char16_t* p = s; *p != 0; ++p) {
michael@0:             NS_ASSERTION(*p >= '0' && *p <= '9', "not a digit");
michael@0:             if (*p < '0' || *p > '9')
michael@0:                 break;
michael@0: 
michael@0:             nextVal *= 10;
michael@0:             nextVal += *p - '0';
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     static const char kRDFNameSpaceURI[] = RDF_NAMESPACE_URI;
michael@0:     char buf[sizeof(kRDFNameSpaceURI) + 16];
michael@0:     nsFixedCString nextValStr(buf, sizeof(buf), 0);
michael@0:     nextValStr = kRDFNameSpaceURI;
michael@0:     nextValStr.Append("_");
michael@0:     nextValStr.AppendInt(nextVal, 10);
michael@0: 
michael@0:     rv = gRDFService->GetResource(nextValStr, aResult);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     // Now increment the RDF:nextVal property.
michael@0:     rv = mDataSource->Unassert(mContainer, kRDF_nextVal, nextValLiteral);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     ++nextVal;
michael@0:     nextValStr.Truncate();
michael@0:     nextValStr.AppendInt(nextVal, 10);
michael@0: 
michael@0:     rv = gRDFService->GetLiteral(NS_ConvertASCIItoUTF16(nextValStr).get(), getter_AddRefs(nextValLiteral));
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     rv = mDataSource->Assert(mContainer, kRDF_nextVal, nextValLiteral, true);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     if (RDF_SEQ_LIST_LIMIT == nextVal)
michael@0:     {
michael@0:         // focal point for RDF container mutation;
michael@0:         // basically, provide a hint to allow for fast access
michael@0:         nsCOMPtr<nsIRDFInMemoryDataSource> inMem = do_QueryInterface(mDataSource);
michael@0:         if (inMem)
michael@0:         {
michael@0:             // ignore error; failure just means slower access
michael@0:             (void)inMem->EnsureFastContainment(mContainer);
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     return NS_OK;
michael@0: }