editor/libeditor/JoinNodesTransaction.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 "JoinNodesTransaction.h"
   7
   8 #include "EditorDOMPoint.h"   // for EditorDOMPoint, etc.
   9 #include "HTMLEditHelpers.h"  // for SplitNodeResult
  10 #include "HTMLEditor.h"       // for HTMLEditor
  11 #include "HTMLEditorInlines.h"
  12 #include "HTMLEditUtils.h"
  13
  14 #include "mozilla/Logging.h"
  15 #include "mozilla/ToString.h"
  16 #include "mozilla/dom/Text.h"
  17
  18 #include "nsAString.h"
  19 #include "nsDebug.h"          // for NS_ASSERTION, etc.
  20 #include "nsError.h"          // for NS_ERROR_NULL_POINTER, etc.
  21 #include "nsIContent.h"       // for nsIContent
  22 #include "nsISupportsImpl.h"  // for QueryInterface, etc.
  23
  24 namespace mozilla {
  25
  26 using namespace dom;
  27
  28 // static
  29 already_AddRefed<JoinNodesTransaction> JoinNodesTransaction::MaybeCreate(
  30     HTMLEditor& aHTMLEditor, nsIContent& aLeftContent,
  31     nsIContent& aRightContent) {
  32   RefPtr<JoinNodesTransaction> transaction =
  33       new JoinNodesTransaction(aHTMLEditor, aLeftContent, aRightContent);
  34   if (NS_WARN_IF(!transaction->CanDoIt())) {
  35     return nullptr;
  36   }
  37   return transaction.forget();
  38 }
  39
  40 JoinNodesTransaction::JoinNodesTransaction(HTMLEditor& aHTMLEditor,
  41                                            nsIContent& aLeftContent,
  42                                            nsIContent& aRightContent)
  43     : mHTMLEditor(&aHTMLEditor),
  44       mRemovedContent(&aRightContent),
  45       mKeepingContent(&aLeftContent) {
  46   // printf("JoinNodesTransaction size: %zu\n", sizeof(JoinNodesTransaction));
  47   static_assert(sizeof(JoinNodesTransaction) <= 64,
  48                 "Transaction classes may be created a lot and may be alive "
  49                 "long so that keep the foot print smaller as far as possible");
  50 }
  51
  52 std::ostream& operator<<(std::ostream& aStream,
  53                          const JoinNodesTransaction& aTransaction) {
  54   aStream << "{ mParentNode=" << aTransaction.mParentNode.get();
  55   if (aTransaction.mParentNode) {
  56     aStream << " (" << *aTransaction.mParentNode << ")";
  57   }
  58   aStream << ", mRemovedContent=" << aTransaction.mRemovedContent.get();
  59   if (aTransaction.mRemovedContent) {
  60     aStream << " (" << *aTransaction.mRemovedContent << ")";
  61   }
  62   aStream << ", mKeepingContent=" << aTransaction.mKeepingContent.get();
  63   if (aTransaction.mKeepingContent) {
  64     aStream << " (" << *aTransaction.mKeepingContent << ")";
  65   }
  66   aStream << ", mJoinedOffset=" << aTransaction.mJoinedOffset
  67           << ", mHTMLEditor=" << aTransaction.mHTMLEditor.get() << " }";
  68   return aStream;
  69 }
  70
  71 NS_IMPL_CYCLE_COLLECTION_INHERITED(JoinNodesTransaction, EditTransactionBase,
  72                                    mHTMLEditor, mParentNode, mRemovedContent,
  73                                    mKeepingContent)
  74
  75 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(JoinNodesTransaction)
  76 NS_INTERFACE_MAP_END_INHERITING(EditTransactionBase)
  77
  78 bool JoinNodesTransaction::CanDoIt() const {
  79   if (NS_WARN_IF(!mKeepingContent) || NS_WARN_IF(!mRemovedContent) ||
  80       NS_WARN_IF(!mHTMLEditor) ||
  81       NS_WARN_IF(mRemovedContent->IsBeingRemoved()) ||
  82       !mKeepingContent->IsInComposedDoc()) {
  83     return false;
  84   }
  85   return HTMLEditUtils::IsRemovableFromParentNode(*mRemovedContent);
  86 }
  87
  88 // After DoTransaction() and RedoTransaction(), the left node is removed from
  89 // the content tree and right node remains.
  90 NS_IMETHODIMP JoinNodesTransaction::DoTransaction() {
  91   MOZ_LOG(GetLogModule(), LogLevel::Info,
  92           ("%p JoinNodesTransaction::%s this=%s", this, __FUNCTION__,
  93            ToString(*this).c_str()));
  94
  95   return DoTransactionInternal(RedoingTransaction::No);
  96 }
  97
  98 nsresult JoinNodesTransaction::DoTransactionInternal(
  99     RedoingTransaction aRedoingTransaction) {
 100   if (MOZ_UNLIKELY(NS_WARN_IF(!mHTMLEditor) || NS_WARN_IF(!mKeepingContent) ||
 101                    NS_WARN_IF(!mRemovedContent) ||
 102                    NS_WARN_IF(mRemovedContent->IsBeingRemoved()))) {
 103     return NS_ERROR_NOT_AVAILABLE;
 104   }
 105
 106   nsINode* removingContentParentNode = mRemovedContent->GetParentNode();
 107   if (MOZ_UNLIKELY(NS_WARN_IF(!removingContentParentNode))) {
 108     return NS_ERROR_NOT_AVAILABLE;
 109   }
 110
 111   // Verify that the joining content nodes have the same parent
 112   if (MOZ_UNLIKELY(removingContentParentNode !=
 113                    mKeepingContent->GetParentNode())) {
 114     NS_ASSERTION(false, "Nodes do not have same parent");
 115     return NS_ERROR_NOT_AVAILABLE;
 116   }
 117
 118   // Set this instance's mParentNode.  Other methods will see a non-null
 119   // mParentNode and know all is well
 120   mParentNode = removingContentParentNode;
 121   // For now, setting mJoinedOffset to removed content length so that
 122   // CreateJoinedPoint returns a point in mKeepingContent whose offset is
 123   // the result if all content in mRemovedContent are moved to start or end of
 124   // mKeepingContent without any intervention.  The offset will be adjusted
 125   // below.
 126   mJoinedOffset = mKeepingContent->Length();
 127
 128   const OwningNonNull<HTMLEditor> htmlEditor = *mHTMLEditor;
 129   const OwningNonNull<nsIContent> removingContent = *mRemovedContent;
 130   const OwningNonNull<nsIContent> keepingContent = *mKeepingContent;
 131   nsresult rv;
 132   // Let's try to get actual joined point with the tacker.
 133   auto joinNodesPoint = EditorDOMPoint::AtEndOf(keepingContent);
 134   {
 135     AutoTrackDOMPoint trackJoinNodePoint(htmlEditor->RangeUpdaterRef(),
 136                                          &joinNodesPoint);
 137     rv = htmlEditor->DoJoinNodes(keepingContent, removingContent);
 138     NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "HTMLEditor::DoJoinNodes() failed");
 139   }
 140   // Adjust join node offset to the actual offset where the original first
 141   // content of the right node is.
 142   mJoinedOffset = joinNodesPoint.Offset();
 143
 144   if (aRedoingTransaction == RedoingTransaction::No) {
 145     htmlEditor->DidJoinNodesTransaction(*this, rv);
 146   }
 147
 148   return rv;
 149 }
 150
 151 // XXX: What if instead of split, we just deleted the unneeded children of
 152 //     mRight and re-inserted mLeft?
 153 NS_IMETHODIMP JoinNodesTransaction::UndoTransaction() {
 154   MOZ_LOG(GetLogModule(), LogLevel::Info,
 155           ("%p JoinNodesTransaction::%s this=%s", this, __FUNCTION__,
 156            ToString(*this).c_str()));
 157
 158   if (NS_WARN_IF(!mParentNode) || NS_WARN_IF(!mKeepingContent) ||
 159       NS_WARN_IF(!mRemovedContent) || NS_WARN_IF(!mHTMLEditor)) {
 160     return NS_ERROR_NOT_AVAILABLE;
 161   }
 162
 163   const OwningNonNull<HTMLEditor> htmlEditor = *mHTMLEditor;
 164   const OwningNonNull<nsIContent> removedContent = *mRemovedContent;
 165
 166   Result<SplitNodeResult, nsresult> splitNodeResult = htmlEditor->DoSplitNode(
 167       CreateJoinedPoint<EditorDOMPoint>(), removedContent);
 168   if (MOZ_UNLIKELY(splitNodeResult.isErr())) {
 169     NS_WARNING("HTMLEditor::DoSplitNode() failed");
 170     return splitNodeResult.unwrapErr();
 171   }
 172   // When adding caret suggestion to SplitNodeResult, here didn't change
 173   // selection so that just ignore it.
 174   splitNodeResult.inspect().IgnoreCaretPointSuggestion();
 175   return NS_OK;
 176 }
 177
 178 NS_IMETHODIMP JoinNodesTransaction::RedoTransaction() {
 179   MOZ_LOG(GetLogModule(), LogLevel::Info,
 180           ("%p JoinNodesTransaction::%s this=%s", this, __FUNCTION__,
 181            ToString(*this).c_str()));
 182   return DoTransactionInternal(RedoingTransaction::Yes);
 183 }
 184
 185 }  // namespace mozilla