/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * 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
 * 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.apache.hadoop.hdds.security.x509.certificate.authority;

import org.apache.hadoop.hdds.security.SecurityConfig;
import org.bouncycastle.cert.X509CertificateHolder;
import org.bouncycastle.operator.OperatorCreationException;
import org.bouncycastle.pkcs.PKCS10CertificationRequest;

import java.io.IOException;
import java.security.PrivateKey;
import java.util.Date;
import java.util.concurrent.CompletableFuture;

/**
 * Certificate Approver interface is used to inspectCSR a certificate.
 */
public interface CertificateApprover {
  /**
   * Approves a Certificate Request based on the policies of this approver.
   *
   * @param csr - Certificate Signing Request.
   * @return - Future that will be contain the certificate or exception.
   */
  CompletableFuture<X509CertificateHolder>
      inspectCSR(PKCS10CertificationRequest csr);

  /**
   * Approves a Certificate Request based on the policies of this approver.
   *
   * @param csr - Certificate Signing Request.
   * @return - Future that will be contain the certificate or exception.
   * @throws IOException - On Error.
   */
  CompletableFuture<X509CertificateHolder>
      inspectCSR(String csr) throws IOException;

  /**
   * Sign function signs a Certificate.
   * @param config - Security Config.
   * @param caPrivate - CAs private Key.
   * @param caCertificate - CA Certificate.
   * @param validFrom - Begin Date
   * @param validTill - End Date
   * @param certificationRequest - Certification Request.
   * @param scmId - SCM id.
   * @param clusterId - Cluster id.
   * @return Signed Certificate.
   * @throws IOException - On Error
   * @throws OperatorCreationException - on Error.
   */
  @SuppressWarnings("ParameterNumber")
  X509CertificateHolder sign(
      SecurityConfig config,
      PrivateKey caPrivate,
      X509CertificateHolder caCertificate,
      Date validFrom,
      Date validTill,
      PKCS10CertificationRequest certificationRequest,
      String scmId,
      String clusterId)
      throws IOException, OperatorCreationException;


  /**
   * Approval Types for a certificate request.
   */
  enum ApprovalType {
    KERBEROS_TRUSTED, /* The Request came from a DN using Kerberos Identity*/
    MANUAL, /* Wait for a Human being to inspect CSR of this certificate */
    TESTING_AUTOMATIC /* For testing purpose, Automatic Approval. */
  }

}
