/**
 * Copyright 2005-2016 The Kuali Foundation
 *
 * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
 *
 * 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.kuali.rice.krad.datadictionary.validation.constraint.resolver;

import org.kuali.rice.krad.datadictionary.validation.capability.Constrainable;
import org.kuali.rice.krad.datadictionary.validation.capability.LengthConstrainable;
import org.kuali.rice.krad.datadictionary.validation.constraint.Constraint;

import java.util.Collections;
import java.util.List;

/**
 * An object that returns the constrainable definition itself as a list for a definition implementing the capability
 * {@link Constrainable}.
 * This definition must also implement the interface {@link Constraint}, or a ClassCastException will be thrown.
 *
 * An example is {@link LengthConstrainable}, where members of the definition itself need to be made available to the
 * ConstraintProcessor.
 *
 * @author Kuali Rice Team (rice.collab@kuali.org)
 */
public class DefinitionConstraintResolver<T extends Constrainable> implements ConstraintResolver<T> {

    @Override
    public <C extends Constraint> List<C> resolve(T definition) throws ClassCastException {
        if (definition instanceof Constraint) {
            @SuppressWarnings("unchecked") C constraint = (C) definition;
            return Collections.singletonList(constraint);
        }
        /*        else if(definiton instanceof InputField){
            C constraint = (C)definition.get
        }*/
        throw new ClassCastException(
                "DefinitionConstraintResolver can only be used for a definition that implements both Constraint and Constrainable, or derives from a class that does.");
    }

}
