1 files changed, 154 insertions, 0 deletions
diff --git a/editor/libeditor/DeleteTextTransaction.cpp b/editor/libeditor/DeleteTextTransaction.cpp
new file mode 100644
index 0000000000..6e759db341
--- /dev/null
+++ b/editor/libeditor/DeleteTextTransaction.cpp
@@ -0,0 +1,154 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "DeleteTextTransaction.h"
+
+#include "HTMLEditUtils.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/EditorBase.h"
+#include "mozilla/EditorDOMPoint.h"
+#include "mozilla/SelectionState.h"
+#include "mozilla/dom/Selection.h"
+#include "nsDebug.h"
+#include "nsError.h"
+#include "nsISupportsImpl.h"
+#include "nsAString.h"
+
+namespace mozilla {
+
+using namespace dom;
+
+// static
+already_AddRefed<DeleteTextTransaction> DeleteTextTransaction::MaybeCreate(
+    EditorBase& aEditorBase, Text& aTextNode, uint32_t aOffset,
+    uint32_t aLengthToDelete) {
+  RefPtr<DeleteTextTransaction> transaction = new DeleteTextTransaction(
+      aEditorBase, aTextNode, aOffset, aLengthToDelete);
+  return transaction.forget();
+}
+
+// static
+already_AddRefed<DeleteTextTransaction>
+DeleteTextTransaction::MaybeCreateForPreviousCharacter(EditorBase& aEditorBase,
+                                                       Text& aTextNode,
+                                                       uint32_t aOffset) {
+  if (NS_WARN_IF(!aOffset)) {
+    return nullptr;
+  }
+
+  nsAutoString data;
+  aTextNode.GetData(data);
+  if (NS_WARN_IF(data.IsEmpty())) {
+    return nullptr;
+  }
+
+  uint32_t length = 1;
+  uint32_t offset = aOffset - 1;
+  if (offset && NS_IS_SURROGATE_PAIR(data[offset - 1], data[offset])) {
+    ++length;
+    --offset;
+  }
+  return DeleteTextTransaction::MaybeCreate(aEditorBase, aTextNode, offset,
+                                            length);
+}
+
+// static
+already_AddRefed<DeleteTextTransaction>
+DeleteTextTransaction::MaybeCreateForNextCharacter(EditorBase& aEditorBase,
+                                                   Text& aTextNode,
+                                                   uint32_t aOffset) {
+  nsAutoString data;
+  aTextNode.GetData(data);
+  if (NS_WARN_IF(aOffset >= data.Length()) || NS_WARN_IF(data.IsEmpty())) {
+    return nullptr;
+  }
+
+  uint32_t length = 1;
+  if (aOffset + 1 < data.Length() &&
+      NS_IS_SURROGATE_PAIR(data[aOffset], data[aOffset + 1])) {
+    ++length;
+  }
+  return DeleteTextTransaction::MaybeCreate(aEditorBase, aTextNode, aOffset,
+                                            length);
+}
+
+DeleteTextTransaction::DeleteTextTransaction(EditorBase& aEditorBase,
+                                             Text& aTextNode, uint32_t aOffset,
+                                             uint32_t aLengthToDelete)
+    : mEditorBase(&aEditorBase),
+      mTextNode(&aTextNode),
+      mOffset(aOffset),
+      mLengthToDelete(aLengthToDelete) {
+  NS_ASSERTION(mTextNode->Length() >= aOffset + aLengthToDelete,
+               "Trying to delete more characters than in node");
+}
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(DeleteTextTransaction, EditTransactionBase,
+                                   mEditorBase, mTextNode)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(DeleteTextTransaction)
+NS_INTERFACE_MAP_END_INHERITING(EditTransactionBase)
+
+bool DeleteTextTransaction::CanDoIt() const {
+  if (NS_WARN_IF(!mTextNode) || NS_WARN_IF(!mEditorBase)) {
+    return false;
+  }
+  return mEditorBase->IsTextEditor() ||
+         HTMLEditUtils::IsSimplyEditableNode(*mTextNode);
+}
+
+NS_IMETHODIMP DeleteTextTransaction::DoTransaction() {
+  if (NS_WARN_IF(!CanDoIt())) {
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+
+  // Get the text that we're about to delete
+  ErrorResult error;
+  mTextNode->SubstringData(mOffset, mLengthToDelete, mDeletedText, error);
+  if (error.Failed()) {
+    NS_WARNING("Text::SubstringData() failed");
+    return error.StealNSResult();
+  }
+
+  OwningNonNull<EditorBase> editorBase = *mEditorBase;
+  OwningNonNull<Text> textNode = *mTextNode;
+  editorBase->DoDeleteText(textNode, mOffset, mLengthToDelete, error);
+  if (error.Failed()) {
+    NS_WARNING("EditorBase::DoDeleteText() failed");
+    return error.StealNSResult();
+  }
+
+  editorBase->RangeUpdaterRef().SelAdjDeleteText(textNode, mOffset,
+                                                 mLengthToDelete);
+
+  if (!editorBase->AllowsTransactionsToChangeSelection()) {
+    return NS_OK;
+  }
+
+  RefPtr<Selection> selection = editorBase->GetSelection();
+  if (NS_WARN_IF(!selection)) {
+    return NS_ERROR_FAILURE;
+  }
+  selection->CollapseInLimiter(EditorRawDOMPoint(textNode, mOffset), error);
+  NS_WARNING_ASSERTION(!error.Failed(),
+                       "Selection::CollapseInLimiter() failed");
+  return error.StealNSResult();
+}
+
+// XXX: We may want to store the selection state and restore it properly.  Was
+//     it an insertion point or an extended selection?
+NS_IMETHODIMP DeleteTextTransaction::UndoTransaction() {
+  if (NS_WARN_IF(!CanDoIt())) {
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+  RefPtr<EditorBase> editorBase = mEditorBase;
+  RefPtr<Text> textNode = mTextNode;
+  ErrorResult error;
+  editorBase->DoInsertText(*textNode, mOffset, mDeletedText, error);
+  NS_WARNING_ASSERTION(!error.Failed(), "EditorBase::DoInsertText() failed");
+  return error.StealNSResult();
+}
+
+}  // namespace mozilla