/*******************************************************************************
 * Breakout Cave Survey Visualizer
 *
 * Copyright (C) 2014 James Edwards
 *
 * jedwards8 at fastmail dot fm
 *
 * 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 2 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, write to the Free Software Foundation, Inc., 51
 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *******************************************************************************/
package org.andork.bind;

import org.andork.event.BasicPropertyChangeListener;
import org.andork.q.QMap;

public class QMapKeyedBinder<K, V> extends Binder<V> implements BasicPropertyChangeListener {
	public static <K, V> QMapKeyedBinder<K, V> bindKeyed(Binder<? extends K> keyBinder,
			Binder<? extends QMap<? super K, V, ?>> mapBinder) {
		return new QMapKeyedBinder<K, V>().bind(keyBinder, mapBinder);
	}

	Binder<? extends K> keyBinder;

	Binder<? extends QMap<? super K, V, ?>> mapBinder;
	K key;
	QMap<? super K, ? super V, ?> map;

	V value;

	public QMapKeyedBinder<K, V> bind(Binder<? extends K> keyBinder,
			Binder<? extends QMap<? super K, V, ?>> mapBinder) {
		boolean update = this.keyBinder != keyBinder || this.mapBinder != mapBinder;

		if (this.keyBinder != keyBinder) {
			if (this.keyBinder != null) {
				unbind0(this.keyBinder, this);
			}
			this.keyBinder = keyBinder;
			if (keyBinder != null) {
				bind0(keyBinder, this);
			}
		}
		if (this.mapBinder != mapBinder) {
			if (this.mapBinder != null) {
				unbind0(mapBinder, this);
			}
			this.mapBinder = mapBinder;
			if (mapBinder != null) {
				bind0(mapBinder, this);
			}
		}

		if (update) {
			update(false);
		}
		return this;
	}

	@Override
	public V get() {
		return value;
	}

	@Override
	public void propertyChange(Object source, Object property, Object oldValue, Object newValue, int index) {
		if (source == map && property == key) {
			update(false);
		}
	}

	@Override
	public void set(V newValue) {
		if (map != null && key != null) {
			map.put(key, newValue);
		}
	}

	public void unbind() {
		bind(null, null);
	}

	@Override
	public void update(boolean force) {
		K newKey = keyBinder == null ? null : keyBinder.get();
		QMap<? super K, V, ?> newMap = mapBinder == null ? null : mapBinder.get();
		V newValue = newKey == null || newMap == null ? null : newMap.get(newKey);

		if (key != newKey || map != newMap) {
			if (map != null && key != null) {
				map.changeSupport().removePropertyChangeListener(key, this);
			}
			map = newMap;
			key = newKey;
			if (newMap != null && newKey != null) {
				newMap.changeSupport().addPropertyChangeListener(newKey, this);
			}
		}
		if (force || value != newValue) {
			value = newValue;
			updateDownstream(force);
		}
	}
}