/*******************************************************************************
 * Copyright (c) 2014, 2015IBM Corporation and others.
 * 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:
 *     IBM Corporation - initial API and implementation
 *     Lars Vogel <Lars.Vogel@vogella.com> - Bug 472654
 ******************************************************************************/

package org.eclipse.e4.ui.workbench.modeling;

import java.util.ArrayList;
import java.util.List;
import org.eclipse.e4.ui.model.application.MApplicationElement;
import org.eclipse.e4.ui.workbench.Selector;

/**
 * This is an implementation of a Selector that implements the existing 'findElements'. Clients may
 * subclass this and override the 'select' method in order to define custom filters.
 *
 * @since 1.1
 *
 */
public class ElementMatcher implements Selector {
	private String id = null;
	private Class<?> clazz = null;
	private List<String> tagsToMatch = null;

	/**
	 * @param id
	 *            The elementId of the desired element
	 * @param clazz
	 *            The class specification of the desired element
	 * @param tag
	 *            A tag which must be specified on the desired element
	 *
	 */
	public ElementMatcher(String id, Class<?> clazz, String tag) {
		this.id = id;
		this.clazz = clazz;

		if (tag != null) {
			tagsToMatch = new ArrayList<>();
			tagsToMatch.add(tag);
		}
	}

	/**
	 * @param id
	 *            The elementId of the desired element
	 * @param clazz
	 *            The class specification of the desired element
	 * @param tagsToMatch
	 *            A list of tags which must <b>all</b> be specified on the desired element
	 *
	 */
	public ElementMatcher(String id, Class<?> clazz, List<String> tagsToMatch) {
		this.id = id;
		this.clazz = clazz;
		this.tagsToMatch = tagsToMatch;
	}

	@Override
	public boolean select(MApplicationElement element) {
		if (id != null && !id.equals(element.getElementId())) {
			return false;
		}

		if (clazz != null && !(clazz.isInstance(element))) {
			return false;
		}

		if (tagsToMatch != null) {
			List<String> elementTags = element.getTags();
			for (String tag : tagsToMatch) {
				if (!elementTags.contains(tag)) {
					return false;
				}
			}
		}

		return true;
	}
}