/*
 * Copyright 2008 the original author or authors.
 * 
 * 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.wamblee.system.graph.component;

import org.wamblee.system.graph.Edge;
import org.wamblee.system.graph.EdgeFilter;

/**
 * Filter used to explicitly connect required and provided interfaces within a
 * container.
 * 
 * @author Erik Brakkee
 * 
 */
public class ConnectExternalProvidedProvidedFilter implements EdgeFilter {

    private String _externalProvided;
    private String _component;
    private String _provided;

    public ConnectExternalProvidedProvidedFilter(String aExternalProvided, String aComponent,
            String aProvided) {
        _externalProvided = aExternalProvided; 
        _component = aComponent; 
        _provided = aProvided; 
        if ( _externalProvided == null ) { 
            throw new IllegalArgumentException("External provided interface name must be specified."); 
        }
        if ( _component == null ) { 
            throw new IllegalArgumentException("Component name must be specified");
        }
        if ( _provided == null ) { 
            throw new IllegalArgumentException("Provided interface name of internal component must be specified");
        }
    }

    @Override
    public boolean isViolated(Edge aEdge) {
        if (aEdge.getFrom() instanceof ExternalProvidedInterfaceNode
                && aEdge.getTo() instanceof ProvidedInterfaceNode) {
            return isViolated((ExternalProvidedInterfaceNode) aEdge.getFrom(),
                    (ProvidedInterfaceNode) aEdge.getTo());
        }
        return false;
    }

    private boolean isViolated(ExternalProvidedInterfaceNode aFrom,
            ProvidedInterfaceNode aTo) {
        if ( !aFrom.getName().equals(_externalProvided)) { 
            return false; // wrong provided interface.
        }
        if ( aTo.getComponent().getName().equals(_component) && 
               aTo.getProvided().getName().equals(_provided) ) { 
            return false; // ok 
        }
        return true; 
    }
}