/*
 * Reference ETL Parser for Java
 * Copyright (c) 2000-2009 Constantine A Plotnikov
 *
 * Permission is hereby granted, free of charge, to any person 
 * obtaining a copy of this software and associated documentation 
 * files (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge, 
 * publish, distribute, sublicense, and/or sell copies of the Software, 
 * and to permit persons to whom the Software is furnished to do so, 
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be 
 * included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 
 * SOFTWARE. 
 */
package net.sf.etl.parsers.internal.term_parser.compiler.nodes;

import java.util.Set;

import net.sf.etl.parsers.internal.term_parser.compiler.StateMachineBuilder;
import net.sf.etl.parsers.internal.term_parser.states.CallResultState;
import net.sf.etl.parsers.internal.term_parser.states.CallState;
import net.sf.etl.parsers.internal.term_parser.states.LookAheadSet;
import net.sf.etl.parsers.internal.term_parser.states.State;

/**
 * A call of activation factory. Note that it is assumed that called production
 * is never matches empty sequence of tokens and always either consume something
 * or exits with error.
 * 
 * @author const
 */
public class CallNode extends Node {
	/** an activation factory */
	private final StateMachineBuilder factoryBuilder;

	/**
	 * A constructor for call node
	 * 
	 * @param factoryBuilder
	 *            a builder for invoked activation factory
	 */
	public CallNode(StateMachineBuilder factoryBuilder) {
		super();
		this.factoryBuilder = factoryBuilder;
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public State buildStates(StateMachineBuilder b, State normalExit,
			State errorExit) {
		return new CallState(factoryBuilder.activation(), new CallResultState(
				normalExit, errorExit));
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	protected boolean calcMatchesEmpty() {
		return false;
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	protected LookAheadSet createLookAhead(
			Set<StateMachineBuilder> visitedBuilders) {
		return factoryBuilder.buildLookAhead(visitedBuilders);
	}

}