LibrePCB

/*
 * LibrePCB - Professional EDA for everyone!
 * Copyright (C) 2013 LibrePCB Developers, see AUTHORS.md for contributors.
 * https://librepcb.org/
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef LIBREPCB_EDITOR_UNDOCOMMANDGROUP_H
#define LIBREPCB_EDITOR_UNDOCOMMANDGROUP_H

/*******************************************************************************
 *  Includes
 ******************************************************************************/
#include "undocommand.h"

#include <QtCore>

/*******************************************************************************
 *  Namespace / Forward Declarations
 ******************************************************************************/
namespace librepcb {
namespace editor {

/*******************************************************************************
 *  Class UndoCommandGroup
 ******************************************************************************/

/**
 * @brief The UndoCommandGroup class makes it possible to pack multiple undo
 * commands together (it acts as a parent of it's child commands)
 */
class UndoCommandGroup : public UndoCommand {
  Q_DECLARE_TR_FUNCTIONS(UndoCommandGroup)

public:
  // Constructors / Destructor
  UndoCommandGroup() = delete;
  UndoCommandGroup(const UndoCommandGroup& other) = delete;
  explicit UndoCommandGroup(const QString& text) noexcept;
  ~UndoCommandGroup() noexcept override;

  // Getters
  int getChildCount() const noexcept { return mChildren.count(); }

  // General Methods

  /**
   * @brief Append a new command to the list of child commands
   *
   * @param cmd       The command to add (must not be executed already)
   *
   * @retval true     If the command was executed and has done some changes
   * @retval false    If the command was not executed or has done nothing
   *
   * @note If this command was already executed (#execute() called), this method
   *       will also immediately execute the newly added child command.
   * Otherwise, it will be executed as soon as #execute() is called.
   *
   * @warning This method must not be called after #undo() was called the first
   * time.
   */
  bool appendChild(UndoCommand* cmd);

  // Operator Overloadings
  UndoCommandGroup& operator=(const UndoCommandGroup& rhs) = delete;

protected:
  /// @copydoc ::librepcb::editor::UndoCommand::performExecute()
  bool performExecute() override;

  /// @copydoc ::librepcb::editor::UndoCommand::performUndo()
  void performUndo() override;

  /// @copydoc ::librepcb::editor::UndoCommand::performRedo()
  void performRedo() override;

  /**
   * @brief Perform custom actions after modifying the undo stack state
   *
   * This gets called after #performExecute(), #performUndo() and
   * #performRedo() if any state was modified to perform additional tasks.
   *
   * @attention Must never throw any exception!
   */
  virtual void performPostExecution() noexcept {}

  /**
   * @brief Helper method for derived classes to execute and add new child
   * commands
   *
   * @param cmd       The command to execute and add (must not be executed
   * already)
   */
  void execNewChildCmd(UndoCommand* cmd);

private:
  /**
   * @brief Memorized return value of #performExecute()
   */
  bool mHasDoneSomething;

  /**
   * @brief All child commands
   *
   * The child which is executed first is at index zero, the last executed
   * command is at the top of the list.
   */
  QList<UndoCommand*> mChildren;
};

/*******************************************************************************
 *  End of File
 ******************************************************************************/

}  // namespace editor
}  // namespace librepcb

#endif