/*******************************************************************************
 * Copyright (c) 2014, 2016 Association for Decentralized Information Management
 * in Industry THTH ry.
 * 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.r.scl.variable;

import org.rosuda.REngine.REXP;

public class RGlobalVariableNode implements RVariableNode {
	private RNodeManager manager;
	private REXP expression;
	private String name;
	
	public RGlobalVariableNode(RNodeManager manager, String name) {
		super();
		
		this.manager = manager;
		this.name = name;
		this.expression = null;
	}

	public RGlobalVariableNode(RNodeManager manager, String name, REXP expression) {
		super();
		
		this.manager = manager;
		this.name = name;
		this.expression = expression;
	}

	@Override
	public REXP getValue() {
		if (expression == null)
			expression = manager.getGlobalValue(name); 
		return expression;
	}

	@Override
	public String getName() {
		return name;
	}

	@Override
	public RVariableNode getParent() {
		return manager;
	}
}