/*
 * 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 2006-2008 Sun Microsystems, Inc.
 * Portions Copyright 2015-2016 ForgeRock AS.
 */
package org.opends.server.api;
import org.forgerock.i18n.LocalizableMessage;



import java.util.List;
import javax.net.ssl.KeyManager;

import org.forgerock.opendj.server.config.server.KeyManagerProviderCfg;
import org.forgerock.opendj.config.server.ConfigException;
import org.opends.server.types.DirectoryException;
import org.opends.server.types.InitializationException;



/**
 * This class defines an API that may be used to obtain a set of
 * {@code javax.net.ssl.KeyManager} objects for use when performing
 * SSL communication.
 *
 * @param <T>
 *          The type of key manager provider configuration handled by
 *          this key manager provider implementation.
 */
@org.opends.server.types.PublicAPI(
     stability=org.opends.server.types.StabilityLevel.VOLATILE,
     mayInstantiate=false,
     mayExtend=true,
     mayInvoke=true)
public abstract class KeyManagerProvider
    <T extends KeyManagerProviderCfg>
{
  /**
   * Initializes this key manager provider based on the information in
   * the provided key manager provider configuration.
   *
   * @param configuration
   *          The key manager provider configuration that contains the
   *          information to use to initialize this key manager
   *          provider.
   * @throws ConfigException
   *           If an unrecoverable problem arises in the process of
   *           performing the initialization as a result of the server
   *           configuration.
   * @throws InitializationException
   *           If a problem occurs during initialization that is not
   *           related to the server configuration.
   */
  public abstract void initializeKeyManagerProvider(T configuration)
      throws ConfigException, InitializationException;


  /**
   *
   * Verifies that an alias is defined in the scope of this Key Manager.
   *
   * @param alias
   *          The alias to check.
   * @return true if the alias exists, false otherwise
   */
  public boolean containsKeyWithAlias(String alias)
  {
    return true;
  }

  /**
   *
   * Verifies that the keystore has at least one usable key.
   *
   * @return true if the keystore has at least one usable key, false otherwise
   */
  public boolean containsAtLeastOneKey()
  {
    return true;
  }

  /**
   * Indicates whether the provided configuration is acceptable for
   * this key manager provider.  It should be possible to call this
   * method on an uninitialized key manager provider instance in order
   * to determine whether the key manager provider would be able to
   * use the provided configuration.
   * <BR><BR>
   * Note that implementations which use a subclass of the provided
   * configuration class will likely need to cast the configuration
   * to the appropriate subclass type.
   *
   * @param  configuration        The key manager provider
   *                              configuration for which to make the
   *                              determination.
   * @param  unacceptableReasons  A list that may be used to hold the
   *                              reasons that the provided
   *                              configuration is not acceptable.
   *
   * @return  {@code true} if the provided configuration is acceptable
   *          for this key manager provider, or {@code false} if not.
   */
  public boolean isConfigurationAcceptable(
                      T configuration,
                      List<LocalizableMessage> unacceptableReasons)
  {
    // This default implementation does not perform any special
    // validation.  It should be overridden by key manager provider
    // implementations that wish to perform more detailed validation.
    return true;
  }



  /**
   * Performs any finalization that may be necessary for this key
   * manager provider.
   */
  public abstract void finalizeKeyManagerProvider();



  /**
   * Retrieves a set of {@code KeyManager} objects that may be used
   * for interactions requiring access to a key manager.
   *
   * @return  A set of {@code KeyManager} objects that may be used for
   *          interactions requiring access to a key manager.
   *
   * @throws  DirectoryException  If a problem occurs while attempting
   *                              to obtain the set of key managers.
   */
  public abstract KeyManager[] getKeyManagers()
         throws DirectoryException;
}