/*
 * @(#)DeleteCommand.java
 *
 * Project:		JHotdraw - a GUI framework for technical drawings
 *				http://www.jhotdraw.org
 *				http://jhotdraw.sourceforge.net
 * Copyright:	© by the original author(s) and all contributors
 * License:		Lesser GNU Public License (LGPL)
 *				http://www.opensource.org/licenses/lgpl-license.html
 */

package CH.ifa.draw.standard;

import CH.ifa.draw.framework.*;
import CH.ifa.draw.util.Undoable;
import CH.ifa.draw.util.UndoableAdapter;

/**
 * Command to delete the selection.
 *
 * @version <$CURRENT_VERSION$>
 */
public class DeleteCommand extends FigureTransferCommand {

   /**
	* Constructs a delete command.
	* @param name the command name
	 * @param newDrawingEditor the DrawingEditor which manages the views
	*/
	public DeleteCommand(String name, DrawingEditor newDrawingEditor) {
		super(name, newDrawingEditor);
	}

	public void execute() {
		super.execute();
		setUndoActivity(createUndoActivity());
		getUndoActivity().setAffectedFigures(view().selectionElements());
		deleteFigures(getUndoActivity().getAffectedFigures());
		view().checkDamage();
	}

	protected boolean isExecutableWithView() {
		return view().selectionCount() > 0;
	}

	/**
	 * Factory method for undo activity
	 */
	protected Undoable createUndoActivity() {
		return new DeleteCommand.UndoActivity(this);
	}

	public static class UndoActivity extends UndoableAdapter {
		private FigureTransferCommand myCommand;

		public UndoActivity(FigureTransferCommand newCommand) {
			super(newCommand.view());
			myCommand = newCommand;
			setUndoable(true);
			setRedoable(true);
		}

		public boolean undo() {
			if (super.undo() && getAffectedFigures().hasMoreElements()) {
				getDrawingView().clearSelection();
				setAffectedFigures(myCommand.insertFigures(getAffectedFigures(), 0, 0));

				return true;
			}

			return false;
		}

		public boolean redo() {
			// do not call execute directly as the selection might has changed
			if (isRedoable()) {
				myCommand.deleteFigures(getAffectedFigures());
				getDrawingView().clearSelection();

				return true;
			}

			return false;
		}
	}
}