1 files changed, 123 insertions, 0 deletions
diff --git a/editor/libeditor/ChangeStyleTransaction.h b/editor/libeditor/ChangeStyleTransaction.h
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+++ b/editor/libeditor/ChangeStyleTransaction.h
@@ -0,0 +1,123 @@
+/* -*- 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/. */
+
+#ifndef mozilla_ChangeStyleTransaction_h
+#define mozilla_ChangeStyleTransaction_h
+
+#include "mozilla/EditTransactionBase.h"  // base class
+#include "nsCOMPtr.h"                     // nsCOMPtr members
+#include "nsCycleCollectionParticipant.h" // various macros
+#include "nsString.h"                     // nsString members
+
+class nsAString;
+class nsIAtom;
+
+namespace mozilla {
+
+namespace dom {
+class Element;
+} // namespace dom
+
+/**
+ * A transaction that changes the value of a CSS inline style of a content
+ * node.  This transaction covers add, remove, and change a property's value.
+ */
+class ChangeStyleTransaction final : public EditTransactionBase
+{
+public:
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(ChangeStyleTransaction,
+                                           EditTransactionBase)
+
+  NS_DECL_ISUPPORTS_INHERITED
+
+  NS_DECL_EDITTRANSACTIONBASE
+
+  NS_IMETHOD RedoTransaction() override;
+
+  enum EChangeType { eSet, eRemove };
+
+  /**
+   * @param aNode           [IN] the node whose style attribute will be changed
+   * @param aProperty       [IN] the name of the property to change
+   * @param aValue          [IN] new value for aProperty, or value to remove
+   * @param aChangeType     [IN] whether to set or remove
+   */
+  ChangeStyleTransaction(dom::Element& aElement,
+                         nsIAtom& aProperty,
+                         const nsAString& aValue,
+                         EChangeType aChangeType);
+
+  /**
+   * Returns true if the list of white-space separated values contains aValue
+   *
+   * @param aValueList      [IN] a list of white-space separated values
+   * @param aValue          [IN] the value to look for in the list
+   * @return                true if the value is in the list of values
+   */
+  static bool ValueIncludes(const nsAString& aValueList,
+                            const nsAString& aValue);
+
+private:
+  virtual ~ChangeStyleTransaction();
+
+  /*
+   * Adds the value aNewValue to list of white-space separated values aValues.
+   *
+   * @param aValues         [IN/OUT] a list of wite-space separated values
+   * @param aNewValue       [IN] a value this code adds to aValues if it is not
+   *                        already in
+   */
+  void AddValueToMultivalueProperty(nsAString& aValues,
+                                    const nsAString& aNewValue);
+
+  /**
+   * Returns true if the property accepts more than one value.
+   *
+   * @param aCSSProperty    [IN] the CSS property
+   * @return                true if the property accepts more than one value
+   */
+  bool AcceptsMoreThanOneValue(nsIAtom& aCSSProperty);
+
+  /**
+   * Remove a value from a list of white-space separated values.
+   * @param aValues         [IN] a list of white-space separated values
+   * @param aRemoveValue    [IN] the value to remove from the list
+   */
+  void RemoveValueFromListOfValues(nsAString& aValues,
+                                   const nsAString& aRemoveValue);
+
+  /**
+   * If the boolean is true and if the value is not the empty string,
+   * set the property in the transaction to that value; if the value
+   * is empty, remove the property from element's styles. If the boolean
+   * is false, just remove the style attribute.
+   */
+  nsresult SetStyle(bool aAttributeWasSet, nsAString& aValue);
+
+  // The element to operate upon.
+  nsCOMPtr<dom::Element> mElement;
+
+  // The CSS property to change.
+  nsCOMPtr<nsIAtom> mProperty;
+
+  // The value to set the property to (ignored if mRemoveProperty==true).
+  nsString mValue;
+
+  // true if the operation is to remove mProperty from mElement.
+  bool mRemoveProperty;
+
+  // The value to set the property to for undo.
+  nsString mUndoValue;
+  // The value to set the property to for redo.
+  nsString mRedoValue;
+  // True if the style attribute was present and not empty before DoTransaction.
+  bool mUndoAttributeWasSet;
+  // True if the style attribute is present and not empty after DoTransaction.
+  bool mRedoAttributeWasSet;
+};
+
+} // namespace mozilla
+
+#endif // #ifndef mozilla_ChangeStyleTransaction_h