/*
 * @(#)FontSizeHandle.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 org.jhotdraw.figures;

import org.jhotdraw.framework.*;
import org.jhotdraw.standard.*;
import org.jhotdraw.util.Undoable;
import org.jhotdraw.util.UndoableAdapter;
import java.awt.*;

/**
 * A Handle to change the font size by direct manipulation.
 *
 * @version <$CURRENT_VERSION$>
 */
public class FontSizeHandle extends LocatorHandle {

	public FontSizeHandle(Figure owner, Locator l) {
		super(owner, l);
	}

	public void invokeStart(int  x, int  y, DrawingView view) {
		setUndoActivity(createUndoActivity(view));
		getUndoActivity().setAffectedFigures(new SingleFigureEnumerator(owner()));
	}

	public void invokeStep (int x, int y, int anchorX, int anchorY, DrawingView view) {
		TextFigure textOwner = (TextFigure) owner();

		FontSizeHandle.UndoActivity activity = (FontSizeHandle.UndoActivity)getUndoActivity();
		int newSize = activity.getFont().getSize() + y-anchorY;
		textOwner.setFont(new Font(activity.getFont().getName(), activity.getFont().getStyle(), newSize));
	}

	public void invokeEnd(int x, int y, int anchorX, int anchorY, DrawingView view) {
		TextFigure textOwner = (TextFigure) owner();
		FontSizeHandle.UndoActivity activity = (FontSizeHandle.UndoActivity)getUndoActivity();
		// there has been no change so there is nothing to undo
		if (textOwner.getFont().getSize() == activity.getOldFontSize()) {
			setUndoActivity(null);
		}
		else {
			activity.setFont(textOwner.getFont());
		}
	}

	public void draw(Graphics g) {
		Rectangle r = displayBox();

		g.setColor(Color.yellow);
		g.fillOval(r.x, r.y, r.width, r.height);

		g.setColor(Color.black);
		g.drawOval(r.x, r.y, r.width, r.height);
	}

	/**
	 * Factory method for undo activity
	 */
	protected Undoable createUndoActivity(DrawingView newView) {
		TextFigure textOwner = (TextFigure)owner();
		return new FontSizeHandle.UndoActivity(newView, textOwner.getFont());
	}

	public static class UndoActivity extends UndoableAdapter {
		private Font myFont;
		private int  myOldFontSize;
		
		public UndoActivity(DrawingView newView, Font newFont) {
			super(newView);
			setFont(newFont);
			setOldFontSize(getFont().getSize());
			setUndoable(true);
			setRedoable(true);
		}

		public boolean undo() {
			if (!super.undo()) {
				return false;
			}
			swapFont();
			return true;
		}

		public boolean redo() {
			// do not call execute directly as the selection might has changed
			if (!isRedoable()) {
				return false;
			}
			swapFont();
			return true;
		}

		protected void swapFont() {
			setOldFontSize(replaceFontSize());
			FigureEnumeration fe = getAffectedFigures();
			while (fe.hasNextFigure()) {
				((TextFigure)fe.nextFigure()).setFont(getFont());
			}
		}
		
		private int replaceFontSize() {
			int tempFontSize = getFont().getSize();
			setFont(new Font(getFont().getName(), getFont().getStyle(), getOldFontSize()));
			return tempFontSize;
		}		
		protected void setFont(Font newFont) {
			myFont = newFont;
		}
		
		public Font getFont() {
			return myFont;
		}
		
		protected void setOldFontSize(int newOldFontSize) {
			myOldFontSize = newOldFontSize;
		}
		
		public int getOldFontSize() {
			return myOldFontSize;
		}
	}
}
