/*******************************************************************************
 * Copyright (c) 2009 IBM 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
 *     Zend Technologies
 *******************************************************************************/
package org.eclipse.php.internal.core.typeinference.evaluators;

import org.eclipse.dltk.ti.GoalState;
import org.eclipse.dltk.ti.goals.ExpressionTypeGoal;
import org.eclipse.dltk.ti.goals.GoalEvaluator;
import org.eclipse.dltk.ti.goals.IGoal;
import org.eclipse.dltk.ti.types.IEvaluatedType;
import org.eclipse.php.core.compiler.ast.nodes.CastExpression;
import org.eclipse.php.internal.core.typeinference.PHPClassType;
import org.eclipse.php.internal.core.typeinference.PHPSimpleTypes;

public class CastEvaluator extends GoalEvaluator {

	private IEvaluatedType result;

	public CastEvaluator(IGoal goal) {
		super(goal);
	}

	public IGoal[] init() {
		ExpressionTypeGoal typedGoal = (ExpressionTypeGoal) goal;
		CastExpression castExpression = (CastExpression) typedGoal.getExpression();
		int operator = castExpression.getCastType();
		switch (operator) {
		case CastExpression.TYPE_INT:
		case CastExpression.TYPE_REAL:
			result = PHPSimpleTypes.NUMBER;
			break;
		case CastExpression.TYPE_STRING:
			result = PHPSimpleTypes.STRING;
			break;
		case CastExpression.TYPE_ARRAY:
			result = PHPSimpleTypes.ARRAY;
			break;
		case CastExpression.TYPE_OBJECT:
			return new IGoal[] { new ExpressionTypeGoal(typedGoal.getContext(), castExpression.getExpr()) };
		case CastExpression.TYPE_BOOL:
			result = PHPSimpleTypes.BOOLEAN;
			break;
		case CastExpression.TYPE_UNSET:
			result = PHPSimpleTypes.NULL;
			break;
		default:
			throw new IllegalArgumentException();
		}
		return IGoal.NO_GOALS;
	}

	public IGoal[] subGoalDone(IGoal subgoal, Object result, GoalState state) {
		if (result instanceof PHPClassType) {
			this.result = (PHPClassType) result;
		} else {
			this.result = new PHPClassType("StdClass"); //$NON-NLS-1$
		}
		return IGoal.NO_GOALS;
	}

	public Object produceResult() {
		return result;
	}
}