/*******************************************************************************
 * Copyright (c) 2007- VTT Technical Research Centre of Finland.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
package org.simantics.g2d.element.handler;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.simantics.g2d.element.IElement;
import org.simantics.utils.datastructures.hints.IHintContext.Key;
import org.simantics.utils.datastructures.hints.IHintContext.KeyOf;
import org.simantics.utils.datastructures.valueinterface.InvalidItemException;
import org.simantics.utils.datastructures.valueinterface.SubscriptionException;
import org.simantics.utils.datastructures.valueinterface.ValueAccess;
import org.simantics.utils.datastructures.valueinterface.ValueMap;
import org.simantics.utils.datastructures.valueinterface.impl.SimpleValueMap;
import org.simantics.utils.datastructures.valueinterface.impl.ValueMonitor;

/**
 * 
 * @Author Toni Kalajainen
 */
public class PropertyHandlerImpl implements PropertyHandler {

	List<String> keys = new ArrayList<String>();
	Set<String> keys2 = new HashSet<String>();
	ValueMap<String> initialValues;
	
	private static final Key KEY_VM = new KeyOf(ValueMonitor.class);
	
	public PropertyHandlerImpl(String ... keys)
	{
		for (String k : keys) {
			this.keys.add(k);
			this.keys2.add(k);
		}
	}
	
	public PropertyHandlerImpl(Collection<String> keys, ValueMap<String> initialValues)
	{
		for (String k : keys) {
			this.keys.add(k);
			this.keys2.add(k);
		}
		if (initialValues!=null)
			this.initialValues = new SimpleValueMap<String>(initialValues);
	}
	
	@Override
	public void enumerateProperties(Collection<String> collection) {
		collection.addAll(keys);
	}

	@Override
	public Object getValue(IElement e, String key) {
		ValueMonitor<String> vm = e.getHint(KEY_VM);
		if (vm==null) return null;
		return vm.get(key);
	}

	@Override
	public void setValueSource(IElement e, ValueAccess<String> access) {
		if (access==null) {
			ValueMonitor<String> vm = e.getHint(KEY_VM);
			if (vm!=null) {			
				e.removeHint(KEY_VM);
				vm.dispose();
			}
			return;
		}
		try {
			ValueMonitor<String> vm = new ValueMonitor<String>(access, keys2, initialValues);
			e.setHint(KEY_VM, vm);
			vm.dispose();
		} catch (SubscriptionException e1) {
			e1.printStackTrace();
		} catch (InvalidItemException e1) {
			e1.printStackTrace();
		}
	}

}