/**
 * Copyright (C) 2015 Valkyrie RCP
 *
 * 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.valkyriercp.rules.constraint;

import org.springframework.util.Assert;
import org.valkyriercp.rules.closure.Closure;

/**
 * Tests the result returned from evaluating a closure closure.
 *
 * @author Keith Donald
 */
public class ClosureResultConstraint implements Constraint {
	private Constraint constraint;

	private Closure closure;

	/**
	 * Creates a ClosureResultConstraint that tests the result returned from
	 * evaulating the specified unary closure.
	 *
	 * @param closure
	 *            The closure to test.
	 * @param constraint
	 *            The predicate that will test the closure return value.
	 */
	public ClosureResultConstraint(Closure closure, Constraint constraint) {
		Assert.notNull(closure, "closure is required");
		Assert.notNull(constraint, "constraint is required");
		this.constraint = constraint;
		this.closure = closure;
	}

	/**
	 * Tests the result returned by evaluating the specified argument against
	 * the configured closure.
	 *
	 * @see Constraint#test(java.lang.Object)
	 */
	public boolean test(Object argument) {
		Object returnValue = closure.call(argument);
		return this.constraint.test(returnValue);
	}

	public Closure getFunction() {
		return closure;
	}

	public Constraint getPredicate() {
		return constraint;
	}

	public String toString() {
		return "[" + closure.toString() + " " + constraint.toString() + "]";
	}
}