/**
 * Copyright 2010 JBoss Inc
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.drools.eclipse.editors.rete.model;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.drools.reteoo.BaseVertex;

/**
 * Rete graph containing a set of vertices that form the graph itself.
 */
public class ReteGraph extends ModelElement {

    /** Property ID to use when a child is added to this diagram. */
    public static final String PROP_CHILD_ADDED   = "ReteGraph.ChildAdded";

    /** Property ID to use when a child is removed from this diagram. */
    public static final String PROP_CHILD_REMOVED = "ReteGraph.ChildRemoved";

    private List               vertices           = new ArrayList();

    /** 
     * Add new BaseVertex to the graph
     * 
     * @param vertex
     * 
     * @return true, if vertex was added, false otherwise
     */
    public boolean addChild(BaseVertex vertex) {
        if ( vertex != null && vertices.add( vertex ) ) {
            firePropertyChange( PROP_CHILD_ADDED,
                                null,
                                vertex );
            return true;
        }
        return false;
    }

    /**
     * Return all Vertices in this graph
     */
    public List getChildren() {
        return vertices;
    }

    /**
     * Remove a vertex from this graph
     * 
     * @param vertex vertex to be removed
     * @return true, if the vertex removal succeeded, false otherwise
     */
    public boolean removeChild(BaseVertex vertex) {
        if ( vertex != null && vertices.remove( vertex ) ) {
            firePropertyChange( PROP_CHILD_REMOVED,
                                null,
                                vertex );
            return true;
        }
        return false;
    }

    /**
     * Removes all vertices from graph.
     */
    public void removeAll() {
        while ( vertices.size() > 0 ) {
            removeChild( ((BaseVertex) vertices.get( 0 )) );
        }
    }

    public void addAll(List children) {
        final Iterator iter = children.iterator();
        while ( iter.hasNext() ) {
            BaseVertex vertex = (BaseVertex) iter.next();
            addChild( vertex );
        }
    }

}