/*
 * The contents of this file are subject to the terms of the Common Development and
 * Distribution License (the License). You may not use this file except in compliance with the
 * License.
 *
 * You can obtain a copy of the License at legal/CDDLv1.0.txt. See the License for the
 * specific language governing permission and limitations under the License.
 *
 * When distributing Covered Software, include this CDDL Header Notice in each file and include
 * the License file at legal/CDDLv1.0.txt. If applicable, add the following below the CDDL
 * Header, with the fields enclosed by brackets [] replaced by your own identifying
 * information: "Portions Copyright [year] [name of copyright owner]".
 *
 * Copyright 2008-2010 Sun Microsystems, Inc.
 * Portions Copyright 2012-2016 ForgeRock AS.
 */
package org.opends.admin.ads.util;

import java.util.Collections;
import java.util.Set;

import org.forgerock.opendj.ldap.Attribute;
import org.forgerock.opendj.ldap.DN;
import org.forgerock.opendj.ldap.Entry;

/**
 * Class providing some utilities to create LDAP connections using JNDI and
 * to manage entries retrieved using JNDI.
 */
public class ConnectionUtils
{
  /** Private constructor: this class cannot be instantiated. */
  private ConnectionUtils()
  {
  }

  /**
   * Returns the first attribute value in this attribute decoded as a UTF-8 string.
   *
   * @param entry
   *          the entry
   * @param attrDesc
   *          the attribute description
   * @return The first attribute value in this attribute decoded as a UTF-8 string.
   */
  public static String firstValueAsString(Entry entry, String attrDesc)
  {
    Attribute attr = entry.getAttribute(attrDesc);
    return (attr != null && !attr.isEmpty()) ? attr.firstValueAsString() : null;
  }

  /**
   * Returns the first value decoded as an Integer, or {@code null} if the attribute does not
   * contain any values.
   *
   * @param entry
   *          the entry
   * @param attrDesc
   *          the attribute description
   * @return The first value decoded as an Integer.
   */
  public static Integer asInteger(Entry entry, String attrDesc)
  {
    Attribute attr = entry.getAttribute(attrDesc);
    return attr != null ? attr.parse().asInteger() : null;
  }

  /**
   * Returns the first value decoded as a Boolean, or {@code null} if the attribute does not contain
   * any values.
   *
   * @param entry
   *          the entry
   * @param attrDesc
   *          the attribute description
   * @return The first value decoded as an Boolean.
   */
  public static Boolean asBoolean(Entry entry, String attrDesc)
  {
    Attribute attr = entry.getAttribute(attrDesc);
    return attr != null ? attr.parse().asBoolean() : null;
  }

  /**
   * Returns the values decoded as a set of Strings.
   *
   * @param entry
   *          the entry
   * @param attrDesc
   *          the attribute description
   * @return The values decoded as a set of Strings. Never {@code null} and never contains
   *         {@code null} values.
   */
  public static Set<String> asSetOfString(Entry entry, String attrDesc)
  {
    Attribute attr = entry.getAttribute(attrDesc);
    return attr != null ? attr.parse().asSetOfString() : Collections.<String> emptySet();
  }

  /**
   * Returns the values decoded as a set of DNs.
   *
   * @param entry
   *          the entry
   * @param attrDesc
   *          the attribute description
   * @return The values decoded as a set of DNs. Never {@code null} and never contains {@code null}
   *         values.
   */
  public static Set<DN> asSetOfDN(Entry entry, String attrDesc)
  {
    Attribute attr = entry.getAttribute(attrDesc);
    return attr != null ? attr.parse().asSetOfDN() : Collections.<DN> emptySet();
  }
}