/**
    * Copyright 2010-2014 The Kuali Foundation
    *
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    *
   * 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.kuali.common.util.encrypt;
  
  import static java.lang.String.format;
  import static org.kuali.common.util.encrypt.openssl.OpenSSL.buildOpenSSLEncryptor;
  import static org.kuali.common.util.log.Loggers.newLogger;
  
  import org.kuali.common.util.encrypt.provider.DefaultEncryptionContextProviderChain;
  import org.kuali.common.util.encrypt.provider.EncryptionContextProvider;
  import org.slf4j.Logger;
  
  import com.google.common.base.Optional;
  
  public final class Encryption {
  
  	private static final Logger logger = newLogger();
  
  	private static Encryptor encryptor;
  
  	public static Encryptor buildEncryptor() {
  		EncryptionContextProvider provider = new DefaultEncryptionContextProviderChain();
  		Optional<EncryptionContext> context = provider.getEncryptionContext();
  		if (context.isPresent()) {
  			return buildOpenSSLEncryptor(context.get());
  		} else {
  			logger.info(format("encryption disabled. no encryption password was located"));
  			return NoOpEncryptor.INSTANCE;
  		}
  	}
  
  	public synchronized static Encryptor getDefaultEncryptor() {
  		if (encryptor == null) {
  			encryptor = buildEncryptor();
  		}
  		return encryptor;
  	}
  
  }