editor/libeditor/SplitNodeTransaction.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "SplitNodeTransaction.h"
   7
   8 #include "mozilla/EditorDOMPoint.h"  // for RangeBoundary, EditorRawDOMPoint
   9 #include "mozilla/HTMLEditor.h"      // for HTMLEditor
  10 #include "mozilla/dom/Selection.h"
  11 #include "nsAString.h"
  12 #include "nsDebug.h"     // for NS_ASSERTION, etc.
  13 #include "nsError.h"     // for NS_ERROR_NOT_INITIALIZED, etc.
  14 #include "nsIContent.h"  // for nsIContent
  15
  16 namespace mozilla {
  17
  18 using namespace dom;
  19
  20 template already_AddRefed<SplitNodeTransaction> SplitNodeTransaction::Create(
  21     HTMLEditor& aHTMLEditor, const EditorDOMPoint& aStartOfRightContent);
  22 template already_AddRefed<SplitNodeTransaction> SplitNodeTransaction::Create(
  23     HTMLEditor& aHTMLEditor, const EditorRawDOMPoint& aStartOfRightContent);
  24
  25 // static
  26 template <typename PT, typename CT>
  27 already_AddRefed<SplitNodeTransaction> SplitNodeTransaction::Create(
  28     HTMLEditor& aHTMLEditor,
  29     const EditorDOMPointBase<PT, CT>& aStartOfRightContent) {
  30   RefPtr<SplitNodeTransaction> transaction =
  31       new SplitNodeTransaction(aHTMLEditor, aStartOfRightContent);
  32   return transaction.forget();
  33 }
  34
  35 template <typename PT, typename CT>
  36 SplitNodeTransaction::SplitNodeTransaction(
  37     HTMLEditor& aHTMLEditor,
  38     const EditorDOMPointBase<PT, CT>& aStartOfRightContent)
  39     : mHTMLEditor(&aHTMLEditor), mStartOfRightContent(aStartOfRightContent) {
  40   MOZ_DIAGNOSTIC_ASSERT(aStartOfRightContent.IsInContentNode());
  41 }
  42
  43 NS_IMPL_CYCLE_COLLECTION_INHERITED(SplitNodeTransaction, EditTransactionBase,
  44                                    mHTMLEditor, mStartOfRightContent,
  45                                    mContainerParentNode, mNewLeftContent)
  46
  47 NS_IMPL_ADDREF_INHERITED(SplitNodeTransaction, EditTransactionBase)
  48 NS_IMPL_RELEASE_INHERITED(SplitNodeTransaction, EditTransactionBase)
  49 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(SplitNodeTransaction)
  50 NS_INTERFACE_MAP_END_INHERITING(EditTransactionBase)
  51
  52 NS_IMETHODIMP SplitNodeTransaction::DoTransaction() {
  53   if (NS_WARN_IF(!mHTMLEditor) ||
  54       NS_WARN_IF(!mStartOfRightContent.IsInContentNode())) {
  55     return NS_ERROR_NOT_AVAILABLE;
  56   }
  57   MOZ_ASSERT(mStartOfRightContent.IsSetAndValid());
  58
  59   // Create a new node
  60   ErrorResult error;
  61   // Don't use .downcast directly because AsContent has an assertion we want
  62   nsCOMPtr<nsINode> cloneOfRightContainer =
  63       mStartOfRightContent.GetContainer()->CloneNode(false, error);
  64   if (error.Failed()) {
  65     NS_WARNING("nsINode::CloneNode() failed");
  66     return error.StealNSResult();
  67   }
  68   if (NS_WARN_IF(!cloneOfRightContainer)) {
  69     return NS_ERROR_UNEXPECTED;
  70   }
  71
  72   mNewLeftContent = cloneOfRightContainer->AsContent();
  73
  74   mContainerParentNode = mStartOfRightContent.GetContainerParent();
  75   if (!mContainerParentNode) {
  76     NS_WARNING("Right container was an orphan node");
  77     return NS_ERROR_NOT_AVAILABLE;
  78   }
  79
  80   OwningNonNull<HTMLEditor> htmlEditor = *mHTMLEditor;
  81   OwningNonNull<nsIContent> newLeftContent = *mNewLeftContent;
  82   OwningNonNull<nsINode> containerParentNode = *mContainerParentNode;
  83   EditorDOMPoint startOfRightContent(mStartOfRightContent);
  84
  85   if (RefPtr<Element> startOfRightNode =
  86           startOfRightContent.GetContainerAsElement()) {
  87     nsresult rv = htmlEditor->MarkElementDirty(*startOfRightNode);
  88     if (NS_WARN_IF(rv == NS_ERROR_EDITOR_DESTROYED)) {
  89       return EditorBase::ToGenericNSResult(rv);
  90     }
  91     NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
  92                          "EditorBase::MarkElementDirty() failed, but ignored");
  93   }
  94
  95   // Insert the new node
  96   htmlEditor->DoSplitNode(startOfRightContent, newLeftContent, error);
  97   if (error.Failed()) {
  98     NS_WARNING("HTMLEditor::DoSplitNode() failed");
  99     return error.StealNSResult();
 100   }
 101
 102   if (!htmlEditor->AllowsTransactionsToChangeSelection()) {
 103     return NS_OK;
 104   }
 105
 106   NS_WARNING_ASSERTION(
 107       !htmlEditor->Destroyed(),
 108       "The editor has gone but SplitNodeTransaction keeps trying to modify "
 109       "Selection");
 110   RefPtr<Selection> selection = htmlEditor->GetSelection();
 111   if (NS_WARN_IF(!selection)) {
 112     return NS_ERROR_FAILURE;
 113   }
 114   EditorRawDOMPoint atEndOfLeftNode(EditorRawDOMPoint::AtEndOf(newLeftContent));
 115   selection->CollapseInLimiter(atEndOfLeftNode, error);
 116   NS_WARNING_ASSERTION(!error.Failed(),
 117                        "Selection::CollapseInLimiter() failed");
 118   return error.StealNSResult();
 119 }
 120
 121 NS_IMETHODIMP SplitNodeTransaction::UndoTransaction() {
 122   if (NS_WARN_IF(!mHTMLEditor) || NS_WARN_IF(!mNewLeftContent) ||
 123       NS_WARN_IF(!mContainerParentNode) ||
 124       NS_WARN_IF(!mStartOfRightContent.IsInContentNode())) {
 125     return NS_ERROR_NOT_AVAILABLE;
 126   }
 127
 128   // This assumes Do inserted the new node in front of the prior existing node
 129   // XXX Perhaps, we should reset mStartOfRightNode with current first child
 130   //     of the right node.
 131   OwningNonNull<HTMLEditor> htmlEditor = *mHTMLEditor;
 132   OwningNonNull<nsIContent> containerContent =
 133       *mStartOfRightContent.ContainerAsContent();
 134   OwningNonNull<nsIContent> newLeftContent = *mNewLeftContent;
 135   nsresult rv = htmlEditor->DoJoinNodes(containerContent, newLeftContent);
 136   NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "HTMLEditor::DoJoinNodes() failed");
 137   return rv;
 138 }
 139
 140 /* Redo cannot simply resplit the right node, because subsequent transactions
 141  * on the redo stack may depend on the left node existing in its previous
 142  * state.
 143  */
 144 NS_IMETHODIMP SplitNodeTransaction::RedoTransaction() {
 145   if (NS_WARN_IF(!mNewLeftContent) || NS_WARN_IF(!mContainerParentNode) ||
 146       NS_WARN_IF(!mStartOfRightContent.IsInContentNode()) ||
 147       NS_WARN_IF(!mHTMLEditor)) {
 148     return NS_ERROR_NOT_AVAILABLE;
 149   }
 150
 151   OwningNonNull<HTMLEditor> htmlEditor = *mHTMLEditor;
 152   OwningNonNull<nsINode> newLeftContent = *mNewLeftContent;
 153   OwningNonNull<nsINode> containerParentNode = *mContainerParentNode;
 154   EditorDOMPoint startOfRightContent(mStartOfRightContent);
 155
 156   // First, massage the existing node so it is in its post-split state
 157   ErrorResult error;
 158   if (startOfRightContent.IsInTextNode()) {
 159     Text* rightTextNode = startOfRightContent.ContainerAsText();
 160     htmlEditor->DoDeleteText(MOZ_KnownLive(*rightTextNode), 0,
 161                              startOfRightContent.Offset(), error);
 162     if (error.Failed()) {
 163       NS_WARNING("EditorBase::DoDeleteText() failed");
 164       return error.StealNSResult();
 165     }
 166   } else {
 167     AutoTArray<OwningNonNull<nsIContent>, 24> movingChildren;
 168     if (nsIContent* child =
 169             startOfRightContent.GetContainer()->GetFirstChild()) {
 170       movingChildren.AppendElement(*child);
 171       for (uint32_t i = 0; i < startOfRightContent.Offset(); i++) {
 172         child = child->GetNextSibling();
 173         if (!child) {
 174           break;
 175         }
 176         movingChildren.AppendElement(*child);
 177       }
 178     }
 179     ErrorResult error;
 180     for (OwningNonNull<nsIContent>& child : movingChildren) {
 181       newLeftContent->AppendChild(child, error);
 182       if (error.Failed()) {
 183         NS_WARNING("nsINode::AppendChild() failed");
 184         return error.StealNSResult();
 185       }
 186     }
 187   }
 188   MOZ_ASSERT(!error.Failed());
 189   // Second, re-insert the left node into the tree
 190   containerParentNode->InsertBefore(newLeftContent,
 191                                     startOfRightContent.GetContainer(), error);
 192   // InsertBefore() may call MightThrowJSException() even if there is no
 193   // error. We don't need the flag here.
 194   error.WouldReportJSException();
 195   NS_WARNING_ASSERTION(!error.Failed(), "nsINode::InsertBefore() failed");
 196   return error.StealNSResult();
 197 }
 198
 199 }  // namespace mozilla