/*
 * [DecryptAndVerify.java]
 *
 * Summary: Decrypt a message and verify the digital signature.
 *
 * Copyright: (c) 2004-2017 Roedy Green, Canadian Mind Products, http://mindprod.com
 *
 * Licence: This software may be copied and used freely for any purpose but military.
 *          http://mindprod.com/contact/nonmil.html
 *
 * Requires: JDK 1.8+
 *
 * Created with: JetBrains IntelliJ IDEA IDE http://www.jetbrains.com/idea/
 *
 * Version History:
 *  1.4 2006-03-05 reformat with IntelliJ and add Javadoc.
 */
package com.mindprod.transporter;

import java.io.IOException;
import java.io.Serializable;

/**
 * Decrypt a message and verify the digital signature.
 * <p/>
 * Uses compression, and  base64u armouring.
 * See Transporter.java for example of use.
 *
 * @author Roedy Green, Canadian Mind Products
 * @version 1.4 2006-03-05 reformat with IntelliJ and add Javadoc.
 * @since 2004-06-08
 */
public final class DecryptAndVerify extends Unwrap
    {
    /**
     * helper for decrypting
     */
    private final Decrypt decrypter;

    /**
     * helper for verifying
     */
    private final Verify verifier;

    /**
     * constructor.
     *
     * @param receiverPrivateKey Receiver's private key
     * @param senderPublicKey    sender's public key (one who signed message).
     */
    public DecryptAndVerify( PrivateKey receiverPrivateKey,
                             PublicKey senderPublicKey )
        {
        super();
        decrypter = new Decrypt( receiverPrivateKey );
        verifier = new Verify( senderPublicKey );
        }

    /**
     * Unwraps encrypted, signed object sent via CIA Post, using serialiasation, compression, signing, encryption and
     * base64u armouring. Does not build parm=value.
     *
     * @param s base64u string to analyse
     *
     * @return reconstituted object
     * @throws IOException if signature validation fails.
     */
    public Serializable unwrap( String s ) throws IOException
        {
        return reconstitute( decompress( verifier.verify( decrypter
                .decrypt( disarmour( s ) ) ) ) );
        }
    } // end DecryptAndVerify