gecko-dev/editor/libeditor/CompositionTransaction.h

/* -*- 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 CompositionTransaction_h
#define CompositionTransaction_h

#include "mozilla/EditTransactionBase.h"   // base class
#include "nsCycleCollectionParticipant.h"  // various macros
#include "nsString.h"                      // mStringToInsert

#define NS_IMETEXTTXN_IID                            \
  {                                                  \
    0xb391355d, 0x346c, 0x43d1, {                    \
      0x85, 0xed, 0x9e, 0x65, 0xbe, 0xe7, 0x7e, 0x48 \
    }                                                \
  }

namespace mozilla {

class EditorBase;
class TextComposition;
class TextRangeArray;

namespace dom {
class Text;
}  // namespace dom

/**
 * CompositionTransaction stores all edit for a composition, i.e.,
 * from compositionstart event to compositionend event.  E.g., inserting a
 * composition string, modifying the composition string or its IME selection
 * ranges and commit or cancel the composition.
 */
class CompositionTransaction final : public EditTransactionBase {
 protected:
  CompositionTransaction(EditorBase& aEditorBase,
                         const nsAString& aStringToInsert, dom::Text& aTextNode,
                         uint32_t aOffset);

 public:
  NS_DECLARE_STATIC_IID_ACCESSOR(NS_IMETEXTTXN_IID)

  /**
   * Creates a composition transaction.  aEditorBase must not return from
   * GetComposition() while calling this method.  Note that this method will
   * update text node information of aEditorBase.mComposition.
   *
   * @param aEditorBase         The editor which has composition.
   * @param aStringToInsert     The new composition string to insert.  This may
   *                            be different from actual composition string.
   *                            E.g., password editor can hide the character
   *                            with a different character.
   * @param aTextNode           The text node which will have aStringToInsert.
   * @param aOffset             The offset in aTextNode where aStringToInsert
   *                            will be inserted.
   */
  static already_AddRefed<CompositionTransaction> Create(
      EditorBase& aEditorBase, const nsAString& aStringToInsert,
      dom::Text& aTextNode, uint32_t aOffset);

  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(CompositionTransaction,
                                           EditTransactionBase)

  NS_DECL_ISUPPORTS_INHERITED

  NS_DECL_EDITTRANSACTIONBASE

  NS_IMETHOD Merge(nsITransaction* aTransaction, bool* aDidMerge) override;

  void MarkFixed();

  static nsresult SetIMESelection(EditorBase& aEditorBase, dom::Text* aTextNode,
                                  uint32_t aOffsetInNode,
                                  uint32_t aLengthOfCompositionString,
                                  const TextRangeArray* aRanges);

 private:
  ~CompositionTransaction();

  nsresult SetSelectionForRanges();

  // The text element to operate upon.
  RefPtr<dom::Text> mTextNode;

  // The offsets into mTextNode where the insertion should be placed.
  uint32_t mOffset;

  uint32_t mReplaceLength;

  // The range list.
  RefPtr<TextRangeArray> mRanges;

  // The text to insert into mTextNode at mOffset.
  nsString mStringToInsert;

  // The editor, which is used to get the selection controller.
  RefPtr<EditorBase> mEditorBase;

  bool mFixed;
};

NS_DEFINE_STATIC_IID_ACCESSOR(CompositionTransaction, NS_IMETEXTTXN_IID)

}  // namespace mozilla

#endif  // #ifndef CompositionTransaction_h