/*
 * 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;

    /**
     * Creates a new ConnectRequiredExternallyRequiredEdgeFilter object.
     * 
     */
    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;
    }
}