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 * regarding copyright ownership.  The ASF licenses this file   *
 * to you under the Apache License, Version 2.0 (the            *
 * "License"); you may not use this file except in compliance   *
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package org.apache.james.transport.mailets.remote.delivery;

import org.apache.james.domainlist.api.DomainList;
import org.apache.james.domainlist.api.DomainListException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class HeloNameProvider {

    private static final Logger LOGGER = LoggerFactory.getLogger(HeloNameProvider.class);
    public static final String LOCALHOST = "localhost";

    private final String heloName;
    private final DomainList domainList;

    public HeloNameProvider(String heloName, DomainList domainList) {
        this.heloName = heloName;
        this.domainList = domainList;
    }

    public String getHeloName() {
        if (heloName == null) {
            // TODO: Maybe we should better just lookup the hostname via dns
            try {
                return domainList.getDefaultDomain().name();
            } catch (DomainListException e) {
                LOGGER.warn("Unable to access DomainList", e);
                return LOCALHOST;
            }
        } else {
            return heloName;
        }
    }
}
