/*
 * 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 ConnectRequiredExternallyRequiredEdgeFilter implements EdgeFilter {

    private String _client;
    private String _required;
    private String _externalRequired;

    public ConnectRequiredExternallyRequiredEdgeFilter(String aClient, String aRequired,
            String aExternalRequired) {
        _client = aClient;
        _required = aRequired;
        _externalRequired = aExternalRequired; 
        if ( _client == null ) { 
            throw new IllegalArgumentException("Client component must be specified"); 
        }
        if ( _required == null ) { 
            throw new IllegalArgumentException("Required interface must be specified");
        }
        if ( _externalRequired == null ) { 
            throw new IllegalArgumentException("External required interface must be specified");
        }
    }

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

    private boolean isViolated(RequiredInterfaceNode aFrom,
            ExternalRequiredInterfaceNode aTo) {
        if ( !aFrom.getComponent().getName().equals(_client)) { 
            return false; // wrong component. 
        }
        if ( !(_required == null || aFrom.getRequired().getName().equals(_required))) { 
            return false; // wrong interface
        }
        if ( !aTo.getRequired().getName().equals(_externalRequired)) { 
            return true; // wrong externally required interface.  
        }
      
        return false; 
    }
}