michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* vim: set ts=2 sw=2 et tw=78: */
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 "nsReferencedElement.h"
michael@0: #include "nsContentUtils.h"
michael@0: #include "nsIURI.h"
michael@0: #include "nsBindingManager.h"
michael@0: #include "nsEscape.h"
michael@0: #include "nsXBLPrototypeBinding.h"
michael@0: #include "nsIDOMNode.h"
michael@0: #include "nsIDOMElement.h"
michael@0: #include "nsCycleCollectionParticipant.h"
michael@0: 
michael@0: void
michael@0: nsReferencedElement::Reset(nsIContent* aFromContent, nsIURI* aURI,
michael@0:                            bool aWatch, bool aReferenceImage)
michael@0: {
michael@0:   NS_ABORT_IF_FALSE(aFromContent, "Reset() expects non-null content pointer");
michael@0: 
michael@0:   Unlink();
michael@0: 
michael@0:   if (!aURI)
michael@0:     return;
michael@0: 
michael@0:   nsAutoCString refPart;
michael@0:   aURI->GetRef(refPart);
michael@0:   // Unescape %-escapes in the reference. The result will be in the
michael@0:   // origin charset of the URL, hopefully...
michael@0:   NS_UnescapeURL(refPart);
michael@0: 
michael@0:   nsAutoCString charset;
michael@0:   aURI->GetOriginCharset(charset);
michael@0:   nsAutoString ref;
michael@0:   nsresult rv = nsContentUtils::ConvertStringFromEncoding(charset,
michael@0:                                                           refPart,
michael@0:                                                           ref);
michael@0:   if (NS_FAILED(rv)) {
michael@0:     // XXX Eww. If fallible malloc failed, using a conversion method that
michael@0:     // assumes UTF-8 and doesn't handle UTF-8 errors.
michael@0:     // https://bugzilla.mozilla.org/show_bug.cgi?id=951082
michael@0:     CopyUTF8toUTF16(refPart, ref);
michael@0:   }
michael@0:   if (ref.IsEmpty())
michael@0:     return;
michael@0: 
michael@0:   // Get the current document
michael@0:   nsIDocument *doc = aFromContent->GetCurrentDoc();
michael@0:   if (!doc)
michael@0:     return;
michael@0: 
michael@0:   nsIContent* bindingParent = aFromContent->GetBindingParent();
michael@0:   if (bindingParent) {
michael@0:     nsXBLBinding* binding = bindingParent->GetXBLBinding();
michael@0:     if (binding) {
michael@0:       bool isEqualExceptRef;
michael@0:       rv = aURI->EqualsExceptRef(binding->PrototypeBinding()->DocURI(),
michael@0:                                  &isEqualExceptRef);
michael@0:       if (NS_SUCCEEDED(rv) && isEqualExceptRef) {
michael@0:         // XXX sXBL/XBL2 issue
michael@0:         // Our content is an anonymous XBL element from a binding inside the
michael@0:         // same document that the referenced URI points to. In order to avoid
michael@0:         // the risk of ID collisions we restrict ourselves to anonymous
michael@0:         // elements from this binding; specifically, URIs that are relative to
michael@0:         // the binding document should resolve to the copy of the target
michael@0:         // element that has been inserted into the bound document.
michael@0:         // If the URI points to a different document we don't need this
michael@0:         // restriction.
michael@0:         nsINodeList* anonymousChildren =
michael@0:           doc->BindingManager()->GetAnonymousNodesFor(bindingParent);
michael@0: 
michael@0:         if (anonymousChildren) {
michael@0:           uint32_t length;
michael@0:           anonymousChildren->GetLength(&length);
michael@0:           for (uint32_t i = 0; i < length && !mElement; ++i) {
michael@0:             mElement =
michael@0:               nsContentUtils::MatchElementId(anonymousChildren->Item(i), ref);
michael@0:           }
michael@0:         }
michael@0: 
michael@0:         // We don't have watching working yet for XBL, so bail out here.
michael@0:         return;
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   bool isEqualExceptRef;
michael@0:   rv = aURI->EqualsExceptRef(doc->GetDocumentURI(), &isEqualExceptRef);
michael@0:   if (NS_FAILED(rv) || !isEqualExceptRef) {
michael@0:     nsRefPtr<nsIDocument::ExternalResourceLoad> load;
michael@0:     doc = doc->RequestExternalResource(aURI, aFromContent,
michael@0:                                        getter_AddRefs(load));
michael@0:     if (!doc) {
michael@0:       if (!load || !aWatch) {
michael@0:         // Nothing will ever happen here
michael@0:         return;
michael@0:       }
michael@0: 
michael@0:       DocumentLoadNotification* observer =
michael@0:         new DocumentLoadNotification(this, ref);
michael@0:       mPendingNotification = observer;
michael@0:       if (observer) {
michael@0:         load->AddObserver(observer);
michael@0:       }
michael@0:       // Keep going so we set up our watching stuff a bit
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   if (aWatch) {
michael@0:     nsCOMPtr<nsIAtom> atom = do_GetAtom(ref);
michael@0:     if (!atom)
michael@0:       return;
michael@0:     atom.swap(mWatchID);
michael@0:   }
michael@0: 
michael@0:   mReferencingImage = aReferenceImage;
michael@0: 
michael@0:   HaveNewDocument(doc, aWatch, ref);
michael@0: }
michael@0: 
michael@0: void
michael@0: nsReferencedElement::ResetWithID(nsIContent* aFromContent, const nsString& aID,
michael@0:                                  bool aWatch)
michael@0: {
michael@0:   nsIDocument *doc = aFromContent->GetCurrentDoc();
michael@0:   if (!doc)
michael@0:     return;
michael@0: 
michael@0:   // XXX Need to take care of XBL/XBL2
michael@0: 
michael@0:   if (aWatch) {
michael@0:     nsCOMPtr<nsIAtom> atom = do_GetAtom(aID);
michael@0:     if (!atom)
michael@0:       return;
michael@0:     atom.swap(mWatchID);
michael@0:   }
michael@0: 
michael@0:   mReferencingImage = false;
michael@0: 
michael@0:   HaveNewDocument(doc, aWatch, aID);
michael@0: }
michael@0: 
michael@0: void
michael@0: nsReferencedElement::HaveNewDocument(nsIDocument* aDocument, bool aWatch,
michael@0:                                      const nsString& aRef)
michael@0: {
michael@0:   if (aWatch) {
michael@0:     mWatchDocument = aDocument;
michael@0:     if (mWatchDocument) {
michael@0:       mElement = mWatchDocument->AddIDTargetObserver(mWatchID, Observe, this,
michael@0:                                                      mReferencingImage);
michael@0:     }
michael@0:     return;
michael@0:   }
michael@0:   
michael@0:   if (!aDocument) {
michael@0:     return;
michael@0:   }
michael@0: 
michael@0:   Element *e = mReferencingImage ? aDocument->LookupImageElement(aRef) :
michael@0:                                    aDocument->GetElementById(aRef);
michael@0:   if (e) {
michael@0:     mElement = e;
michael@0:   }
michael@0: }
michael@0: 
michael@0: void
michael@0: nsReferencedElement::Traverse(nsCycleCollectionTraversalCallback* aCB)
michael@0: {
michael@0:   NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*aCB, "mWatchDocument");
michael@0:   aCB->NoteXPCOMChild(mWatchDocument);
michael@0:   NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(*aCB, "mContent");
michael@0:   aCB->NoteXPCOMChild(mElement);
michael@0: }
michael@0: 
michael@0: void
michael@0: nsReferencedElement::Unlink()
michael@0: {
michael@0:   if (mWatchDocument && mWatchID) {
michael@0:     mWatchDocument->RemoveIDTargetObserver(mWatchID, Observe, this,
michael@0:                                            mReferencingImage);
michael@0:   }
michael@0:   if (mPendingNotification) {
michael@0:     mPendingNotification->Clear();
michael@0:     mPendingNotification = nullptr;
michael@0:   }
michael@0:   mWatchDocument = nullptr;
michael@0:   mWatchID = nullptr;
michael@0:   mElement = nullptr;
michael@0:   mReferencingImage = false;
michael@0: }
michael@0: 
michael@0: bool
michael@0: nsReferencedElement::Observe(Element* aOldElement,
michael@0:                              Element* aNewElement, void* aData)
michael@0: {
michael@0:   nsReferencedElement* p = static_cast<nsReferencedElement*>(aData);
michael@0:   if (p->mPendingNotification) {
michael@0:     p->mPendingNotification->SetTo(aNewElement);
michael@0:   } else {
michael@0:     NS_ASSERTION(aOldElement == p->mElement, "Failed to track content!");
michael@0:     ChangeNotification* watcher =
michael@0:       new ChangeNotification(p, aOldElement, aNewElement);
michael@0:     p->mPendingNotification = watcher;
michael@0:     nsContentUtils::AddScriptRunner(watcher);
michael@0:   }
michael@0:   bool keepTracking = p->IsPersistent();
michael@0:   if (!keepTracking) {
michael@0:     p->mWatchDocument = nullptr;
michael@0:     p->mWatchID = nullptr;
michael@0:   }
michael@0:   return keepTracking;
michael@0: }
michael@0: 
michael@0: NS_IMPL_ISUPPORTS_INHERITED0(nsReferencedElement::ChangeNotification,
michael@0:                              nsRunnable)
michael@0: 
michael@0: NS_IMPL_ISUPPORTS(nsReferencedElement::DocumentLoadNotification,
michael@0:                   nsIObserver)
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsReferencedElement::DocumentLoadNotification::Observe(nsISupports* aSubject,
michael@0:                                                        const char* aTopic,
michael@0:                                                        const char16_t* aData)
michael@0: {
michael@0:   NS_ASSERTION(PL_strcmp(aTopic, "external-resource-document-created") == 0,
michael@0:                "Unexpected topic");
michael@0:   if (mTarget) {
michael@0:     nsCOMPtr<nsIDocument> doc = do_QueryInterface(aSubject);
michael@0:     mTarget->mPendingNotification = nullptr;
michael@0:     NS_ASSERTION(!mTarget->mElement, "Why do we have content here?");
michael@0:     // If we got here, that means we had Reset() called with aWatch ==
michael@0:     // true.  So keep watching if IsPersistent().
michael@0:     mTarget->HaveNewDocument(doc, mTarget->IsPersistent(), mRef);
michael@0:     mTarget->ElementChanged(nullptr, mTarget->mElement);
michael@0:   }
michael@0:   return NS_OK;
michael@0: }