/*
 * 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.accumulo.harness.conf;

import java.io.IOException;
import java.util.Map;

import org.apache.accumulo.cluster.ClusterUser;
import org.apache.accumulo.core.client.security.tokens.AuthenticationToken;
import org.apache.accumulo.core.client.security.tokens.KerberosToken;
import org.apache.accumulo.core.client.security.tokens.PasswordToken;
import org.apache.accumulo.harness.AccumuloClusterHarness;
import org.apache.accumulo.harness.AccumuloClusterHarness.ClusterType;
import org.apache.accumulo.harness.MiniClusterHarness;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.CommonConfigurationKeysPublic;
import org.apache.hadoop.security.UserGroupInformation;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Extract configuration properties for a MiniAccumuloCluster from Java properties
 */
public class AccumuloMiniClusterConfiguration extends AccumuloClusterPropertyConfiguration {
  private static final Logger log = LoggerFactory.getLogger(AccumuloMiniClusterConfiguration.class);
  private static final String TRUE = Boolean.toString(true);

  public static final String ACCUMULO_MINI_PRINCIPAL_KEY = ACCUMULO_MINI_PREFIX + "principal";
  public static final String ACCUMULO_MINI_PRINCIPAL_DEFAULT = "root";
  public static final String ACCUMULO_MINI_PASSWORD_KEY = ACCUMULO_MINI_PREFIX + "password";
  public static final String ACCUMULO_MINI_PASSWORD_DEFAULT = "rootPassword1";

  private final Map<String,String> conf;
  private final boolean saslEnabled;

  public AccumuloMiniClusterConfiguration() {
    ClusterType type = getClusterType();
    if (type != ClusterType.MINI) {
      throw new IllegalStateException("Expected only to see mini cluster state");
    }

    this.conf = getConfiguration(type);
    this.saslEnabled =
        TRUE.equals(System.getProperty(MiniClusterHarness.USE_KERBEROS_FOR_IT_OPTION));
    log.debug("SASL is {}enabled", (saslEnabled ? "" : "not "));
  }

  @Override
  public String getAdminPrincipal() {
    if (saslEnabled) {
      return AccumuloClusterHarness.getKdc().getRootUser().getPrincipal();
    } else {
      String principal = conf.get(ACCUMULO_MINI_PRINCIPAL_KEY);
      if (principal == null) {
        principal = ACCUMULO_MINI_PRINCIPAL_DEFAULT;
      }

      return principal;
    }
  }

  @Override
  public AuthenticationToken getAdminToken() {
    if (saslEnabled) {
      // Turn on Kerberos authentication so UGI acts properly
      final Configuration conf = new Configuration(false);
      conf.set(CommonConfigurationKeysPublic.HADOOP_SECURITY_AUTHENTICATION, "kerberos");
      UserGroupInformation.setConfiguration(conf);

      ClusterUser rootUser = AccumuloClusterHarness.getKdc().getRootUser();
      try {
        UserGroupInformation.loginUserFromKeytab(rootUser.getPrincipal(),
            rootUser.getKeytab().getAbsolutePath());
        return new KerberosToken();
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    } else {
      String password = conf.get(ACCUMULO_MINI_PASSWORD_KEY);
      if (password == null) {
        password = ACCUMULO_MINI_PASSWORD_DEFAULT;
      }

      return new PasswordToken(password);
    }
  }

  @Override
  public ClusterType getClusterType() {
    return ClusterType.MINI;
  }
}