/*
    * Copyright 2014 James Pether Sörling
    * 
    * Licensed 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.
   *
   *	$Id$
   *  $HeadURL$
  */
  package com.hack23.cia.encryption.properties;
  
  import java.security.Security;
  
  import org.bouncycastle.jce.provider.BouncyCastleProvider;
  import org.jasypt.encryption.pbe.StandardPBEStringEncryptor;
  
  /**
   * The Class EncryptProperty.
   */
  public final class EncryptProperty {
  
  	/** The Constant EXPECTED_NUMBER_ARGS. */
  	private static final int EXPECTED_NUMBER_ARGS = 2;
  
  	/** The Constant PBEWITHSHA256AND128BITAES_CBC_BC. */
  	private static final String PBEWITHSHA256AND128BITAES_CBC_BC = "PBEWITHSHA256AND128BITAES-CBC-BC";
  	
  	/** The Constant BC_PROVIDER_NAME. */
  	private static final String BC_PROVIDER_NAME = "BC";
  	
  	/** The Constant ENC_CONTENT_SUFFIX. */
  	private static final String ENC_CONTENT_SUFFIX = ")";
  	
  	/** The Constant ENC_CONTENT_PREFIX. */
  	private static final String ENC_CONTENT_PREFIX = "ENC(";
  	
  	/** The Constant ENCRYPTED_PROPERTY_VALUE. */
  	private static final String ENCRYPTED_PROPERTY_VALUE = "Encrypted property value:";
  	
  	/** The Constant ENCRYPTED_VALUE. */
  	private static final String ENCRYPTED_VALUE = "Encrypted value:";
  	
  	/** The Constant HELP_MESSAGE. */
  	private static final String HELP_MESSAGE = "Encrypt property value with PBEWITHSHA256AND128BITAES_CBC_BC, using symmetric key and value as arguments. ./encryptProperty [key] [value]";
  	
  	
  	/**
  	 * Instantiates a new encrypt property.
  	 */
  	public EncryptProperty() {
  		super();
  	}
  
  	/**
  	 * The main method.
  	 *
  	 * @param args the arguments
  	 */
  	public static void main(String[] args) {
  		if (args.length == EXPECTED_NUMBER_ARGS) {
  			final String encryptValue = new EncryptProperty().encryptValue(args[0], args[1]);
  			System.out.println(ENCRYPTED_VALUE +encryptValue);
  			System.out.println(ENCRYPTED_PROPERTY_VALUE + ENC_CONTENT_PREFIX +encryptValue +ENC_CONTENT_SUFFIX);
  		} else {
  			System.out.println(HELP_MESSAGE);
  		}
  	}
  	
  	/**
  	 * Encrypt value.
  	 *
  	 * @param symmetricKey
  	 *            the symmetric key
  	 * @param value
  	 *            the value
  	 * @return the string
  	 */
  	public String encryptValue(final String symmetricKey,final String value) {
  		return getEncryptor(symmetricKey).encrypt(value);
  		
  	}
  
  	/**
  	 * Gets the encryptor.
  	 *
  	 * @param symmetricKey
  	 *            the symmetric key
  	 * @return the encryptor
  	 */
  	private static StandardPBEStringEncryptor getEncryptor(final String symmetricKey) {
 		Security.addProvider(new BouncyCastleProvider());
 		final StandardPBEStringEncryptor mySecondEncryptor = new StandardPBEStringEncryptor();
 		mySecondEncryptor.setProviderName(BC_PROVIDER_NAME);
 		mySecondEncryptor.setAlgorithm(PBEWITHSHA256AND128BITAES_CBC_BC);
 		mySecondEncryptor.setPassword(symmetricKey);
 		return mySecondEncryptor;
 	}
 
 
 	/**
 	 * Decrypt value.
 	 *
 	 * @param symmetricKey
 	 *            the symmetric key
 	 * @param value
 	 *            the value
 	 * @return the string
 	 */
 	public String decryptValue(final String symmetricKey,final String value) {
 		return getEncryptor(symmetricKey).decrypt(value);
 		
 	}
 
 }