/*******************************************************************************
 * This file is part of logisim-evolution.
 *
 *   logisim-evolution 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.
 *
 *   logisim-evolution 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 logisim-evolution.  If not, see <http://www.gnu.org/licenses/>.
 *
 *   Original code by Carl Burch (http://www.cburch.com), 2011.
 *   Subsequent modifications by :
 *     + Haute École Spécialisée Bernoise
 *       http://www.bfh.ch
 *     + Haute École du paysage, d'ingénierie et d'architecture de Genève
 *       http://hepia.hesge.ch/
 *     + Haute École d'Ingénierie et de Gestion du Canton de Vaud
 *       http://www.heig-vd.ch/
 *   The project is currently maintained by :
 *     + REDS Institute - HEIG-VD
 *       Yverdon-les-Bains, Switzerland
 *       http://reds.heig-vd.ch
 *******************************************************************************/

package com.cburch.logisim.prefs;

import java.util.prefs.PreferenceChangeEvent;
import java.util.prefs.Preferences;

class PrefMonitorDouble extends AbstractPrefMonitor<Double> {
	private double dflt;
	private double value;

	PrefMonitorDouble(String name, double dflt) {
		super(name);
		this.dflt = dflt;
		this.value = dflt;
		Preferences prefs = AppPreferences.getPrefs();
		set(Double.valueOf(prefs.getDouble(name, dflt)));
		prefs.addPreferenceChangeListener(this);
	}

	public Double get() {
		return Double.valueOf(value);
	}

	public void preferenceChange(PreferenceChangeEvent event) {
		Preferences prefs = event.getNode();
		String prop = event.getKey();
		String name = getIdentifier();
		if (prop.equals(name)) {
			double oldValue = value;
			double newValue = prefs.getDouble(name, dflt);
			if (newValue != oldValue) {
				value = newValue;
				AppPreferences.firePropertyChange(name,
						Double.valueOf(oldValue), Double.valueOf(newValue));
			}
		}
	}

	public void set(Double newValue) {
		double newVal = newValue.doubleValue();
		if (value != newVal) {
			AppPreferences.getPrefs().putDouble(getIdentifier(), newVal);
		}
	}
}