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 "JoinSplitNodeDirection.h"  // JoinNodesDirection
  11 #include "HTMLEditor.h"              // for HTMLEditor
  12 #include "HTMLEditorInlines.h"
  13 #include "HTMLEditUtils.h"
  14
  15 #include "mozilla/Logging.h"
  16 #include "mozilla/ToString.h"
  17 #include "mozilla/dom/Text.h"
  18
  19 #include "nsAString.h"
  20 #include "nsDebug.h"          // for NS_ASSERTION, etc.
  21 #include "nsError.h"          // for NS_ERROR_NULL_POINTER, etc.
  22 #include "nsIContent.h"       // for nsIContent
  23 #include "nsISupportsImpl.h"  // for QueryInterface, etc.
  24
  25 namespace mozilla {
  26
  27 using namespace dom;
  28
  29 // static
  30 already_AddRefed<JoinNodesTransaction> JoinNodesTransaction::MaybeCreate(
  31     HTMLEditor& aHTMLEditor, nsIContent& aLeftContent,
  32     nsIContent& aRightContent) {
  33   RefPtr<JoinNodesTransaction> transaction =
  34       new JoinNodesTransaction(aHTMLEditor, aLeftContent, aRightContent);
  35   if (NS_WARN_IF(!transaction->CanDoIt())) {
  36     return nullptr;
  37   }
  38   return transaction.forget();
  39 }
  40
  41 JoinNodesTransaction::JoinNodesTransaction(HTMLEditor& aHTMLEditor,
  42                                            nsIContent& aLeftContent,
  43                                            nsIContent& aRightContent)
  44     : mHTMLEditor(&aHTMLEditor),
  45       mRemovedContent(aHTMLEditor.GetJoinNodesDirection() ==
  46                               JoinNodesDirection::LeftNodeIntoRightNode
  47                           ? &aLeftContent
  48                           : &aRightContent),
  49       mKeepingContent(aHTMLEditor.GetJoinNodesDirection() ==
  50                               JoinNodesDirection::LeftNodeIntoRightNode
  51                           ? &aRightContent
  52                           : &aLeftContent) {
  53   // printf("JoinNodesTransaction size: %zu\n", sizeof(JoinNodesTransaction));
  54   static_assert(sizeof(JoinNodesTransaction) <= 64,
  55                 "Transaction classes may be created a lot and may be alive "
  56                 "long so that keep the foot print smaller as far as possible");
  57 }
  58
  59 std::ostream& operator<<(std::ostream& aStream,
  60                          const JoinNodesTransaction& aTransaction) {
  61   aStream << "{ mParentNode=" << aTransaction.mParentNode.get();
  62   if (aTransaction.mParentNode) {
  63     aStream << " (" << *aTransaction.mParentNode << ")";
  64   }
  65   aStream << ", mRemovedContent=" << aTransaction.mRemovedContent.get();
  66   if (aTransaction.mRemovedContent) {
  67     aStream << " (" << *aTransaction.mRemovedContent << ")";
  68   }
  69   aStream << ", mKeepingContent=" << aTransaction.mKeepingContent.get();
  70   if (aTransaction.mKeepingContent) {
  71     aStream << " (" << *aTransaction.mKeepingContent << ")";
  72   }
  73   aStream << ", mJoinedOffset=" << aTransaction.mJoinedOffset
  74           << ", mHTMLEditor=" << aTransaction.mHTMLEditor.get()
  75           << ", GetJoinNodesDirection()="
  76           << aTransaction.GetJoinNodesDirection() << " }";
  77   return aStream;
  78 }
  79
  80 NS_IMPL_CYCLE_COLLECTION_INHERITED(JoinNodesTransaction, EditTransactionBase,
  81                                    mHTMLEditor, mParentNode, mRemovedContent,
  82                                    mKeepingContent)
  83
  84 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(JoinNodesTransaction)
  85 NS_INTERFACE_MAP_END_INHERITING(EditTransactionBase)
  86
  87 SplitNodeDirection JoinNodesTransaction::GetSplitNodeDirection() const {
  88   return MOZ_LIKELY(mHTMLEditor) ? mHTMLEditor->GetSplitNodeDirection()
  89                                  : SplitNodeDirection::LeftNodeIsNewOne;
  90 }
  91
  92 JoinNodesDirection JoinNodesTransaction::GetJoinNodesDirection() const {
  93   return MOZ_LIKELY(mHTMLEditor) ? mHTMLEditor->GetJoinNodesDirection()
  94                                  : JoinNodesDirection::LeftNodeIntoRightNode;
  95 }
  96
  97 bool JoinNodesTransaction::CanDoIt() const {
  98   if (NS_WARN_IF(!mKeepingContent) || NS_WARN_IF(!mRemovedContent) ||
  99       NS_WARN_IF(!mHTMLEditor) ||
 100       NS_WARN_IF(mRemovedContent->IsBeingRemoved()) ||
 101       !mKeepingContent->IsInComposedDoc()) {
 102     return false;
 103   }
 104   return HTMLEditUtils::IsRemovableFromParentNode(*mRemovedContent);
 105 }
 106
 107 // After DoTransaction() and RedoTransaction(), the left node is removed from
 108 // the content tree and right node remains.
 109 NS_IMETHODIMP JoinNodesTransaction::DoTransaction() {
 110   MOZ_LOG(GetLogModule(), LogLevel::Info,
 111           ("%p JoinNodesTransaction::%s this=%s", this, __FUNCTION__,
 112            ToString(*this).c_str()));
 113
 114   return DoTransactionInternal(RedoingTransaction::No);
 115 }
 116
 117 nsresult JoinNodesTransaction::DoTransactionInternal(
 118     RedoingTransaction aRedoingTransaction) {
 119   if (MOZ_UNLIKELY(NS_WARN_IF(!mHTMLEditor) || NS_WARN_IF(!mKeepingContent) ||
 120                    NS_WARN_IF(!mRemovedContent) ||
 121                    NS_WARN_IF(mRemovedContent->IsBeingRemoved()))) {
 122     return NS_ERROR_NOT_AVAILABLE;
 123   }
 124
 125   nsINode* removingContentParentNode = mRemovedContent->GetParentNode();
 126   if (MOZ_UNLIKELY(NS_WARN_IF(!removingContentParentNode))) {
 127     return NS_ERROR_NOT_AVAILABLE;
 128   }
 129
 130   // Verify that the joining content nodes have the same parent
 131   if (MOZ_UNLIKELY(removingContentParentNode !=
 132                    mKeepingContent->GetParentNode())) {
 133     NS_ASSERTION(false, "Nodes do not have same parent");
 134     return NS_ERROR_NOT_AVAILABLE;
 135   }
 136
 137   // Set this instance's mParentNode.  Other methods will see a non-null
 138   // mParentNode and know all is well
 139   mParentNode = removingContentParentNode;
 140   // For now, setting mJoinedOffset to removed content length so that
 141   // CreateJoinedPoint returns a point in mKeepingContent whose offset is
 142   // the result if all content in mRemovedContent are moved to start or end of
 143   // mKeepingContent without any intervation.  The offset will be adjusted
 144   // below.
 145   mJoinedOffset =
 146       GetJoinNodesDirection() == JoinNodesDirection::LeftNodeIntoRightNode
 147           ? mRemovedContent->Length()
 148           : mKeepingContent->Length();
 149
 150   const OwningNonNull<HTMLEditor> htmlEditor = *mHTMLEditor;
 151   const OwningNonNull<nsIContent> removingContent = *mRemovedContent;
 152   const OwningNonNull<nsIContent> keepingContent = *mKeepingContent;
 153   nsresult rv;
 154   // Let's try to get actual joined point with the tacker.
 155   EditorDOMPoint joinNodesPoint =
 156       GetJoinNodesDirection() == JoinNodesDirection::LeftNodeIntoRightNode
 157           ? EditorDOMPoint(keepingContent, 0u)
 158           : EditorDOMPoint::AtEndOf(keepingContent);
 159   {
 160     AutoTrackDOMPoint trackJoinNodePoint(htmlEditor->RangeUpdaterRef(),
 161                                          &joinNodesPoint);
 162     rv = htmlEditor->DoJoinNodes(keepingContent, removingContent,
 163                                  GetJoinNodesDirection());
 164     NS_WARNING_ASSERTION(NS_SUCCEEDED(rv), "HTMLEditor::DoJoinNodes() failed");
 165   }
 166   // Adjust join node offset to the actual offset where the original first
 167   // content of the right node is.
 168   mJoinedOffset = joinNodesPoint.Offset();
 169
 170   if (aRedoingTransaction == RedoingTransaction::No) {
 171     htmlEditor->DidJoinNodesTransaction(*this, rv);
 172   }
 173
 174   return rv;
 175 }
 176
 177 // XXX: What if instead of split, we just deleted the unneeded children of
 178 //     mRight and re-inserted mLeft?
 179 NS_IMETHODIMP JoinNodesTransaction::UndoTransaction() {
 180   MOZ_LOG(GetLogModule(), LogLevel::Info,
 181           ("%p JoinNodesTransaction::%s this=%s", this, __FUNCTION__,
 182            ToString(*this).c_str()));
 183
 184   if (NS_WARN_IF(!mParentNode) || NS_WARN_IF(!mKeepingContent) ||
 185       NS_WARN_IF(!mRemovedContent) || NS_WARN_IF(!mHTMLEditor)) {
 186     return NS_ERROR_NOT_AVAILABLE;
 187   }
 188
 189   const OwningNonNull<HTMLEditor> htmlEditor = *mHTMLEditor;
 190   const OwningNonNull<nsIContent> removedContent = *mRemovedContent;
 191
 192   Result<SplitNodeResult, nsresult> splitNodeResult =
 193       htmlEditor->DoSplitNode(CreateJoinedPoint<EditorDOMPoint>(),
 194                               removedContent, GetSplitNodeDirection());
 195   if (MOZ_UNLIKELY(splitNodeResult.isErr())) {
 196     NS_WARNING("HTMLEditor::DoSplitNode() failed");
 197     return splitNodeResult.unwrapErr();
 198   }
 199   // When adding caret suggestion to SplitNodeResult, here didn't change
 200   // selection so that just ignore it.
 201   splitNodeResult.inspect().IgnoreCaretPointSuggestion();
 202   return NS_OK;
 203 }
 204
 205 NS_IMETHODIMP JoinNodesTransaction::RedoTransaction() {
 206   MOZ_LOG(GetLogModule(), LogLevel::Info,
 207           ("%p JoinNodesTransaction::%s this=%s", this, __FUNCTION__,
 208            ToString(*this).c_str()));
 209   return DoTransactionInternal(RedoingTransaction::Yes);
 210 }
 211
 212 }  // namespace mozilla