/*
 *
 * This file is part of the iText (R) project.
    Copyright (c) 1998-2017 iText Group NV
 * Authors: Bruno Lowagie, Paulo Soares, et al.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
 * ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
 * OF THIRD PARTY RIGHTS
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Affero General Public License for more details.
 * You should have received a copy of the GNU Affero General Public License
 * along with this program; if not, see http://www.gnu.org/licenses or write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA, 02110-1301 USA, or download the license from the following URL:
 * http://itextpdf.com/terms-of-use/
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * In accordance with Section 7(b) of the GNU Affero General Public License,
 * a covered work must retain the producer line in every PDF that is created
 * or manipulated using iText.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the iText software without
 * disclosing the source code of your own applications.
 * These activities include: offering paid services to customers as an ASP,
 * serving PDFs on the fly in a web application, shipping iText with a closed
 * source product.
 *
 * For more information, please contact iText Software Corp. at this
 * address: sales@itextpdf.com
 */
package com.itextpdf.text.pdf.interfaces;

import java.security.cert.Certificate;

import com.itextpdf.text.DocumentException;

/**
 * Encryption settings are described in section 3.5 (more specifically
 * section 3.5.2) of the PDF Reference 1.7.
 * They are explained in section 3.3.3 of the book 'iText in Action'.
 * The values of the different  preferences were originally stored
 * in class PdfWriter, but they have been moved to this separate interface
 * for reasons of convenience.
 */

public interface PdfEncryptionSettings {

    
    /**
     * Sets the encryption options for this document. The userPassword and the
     * ownerPassword can be null or have zero length. In this case the ownerPassword
     * is replaced by a random string. The open permissions for the document can be
     * AllowPrinting, AllowModifyContents, AllowCopy, AllowModifyAnnotations,
     * AllowFillIn, AllowScreenReaders, AllowAssembly and AllowDegradedPrinting.
     * The permissions can be combined by ORing them.
     * @param userPassword the user password. Can be null or empty
     * @param ownerPassword the owner password. Can be null or empty
     * @param permissions the user permissions
     * @param encryptionType the type of encryption. It can be one of STANDARD_ENCRYPTION_40, STANDARD_ENCRYPTION_128 or ENCRYPTION_AES128.
     * Optionally DO_NOT_ENCRYPT_METADATA can be ored to output the metadata in cleartext
     * @throws DocumentException if the document is already open
     */
    public void setEncryption(byte userPassword[], byte ownerPassword[], int permissions, int encryptionType) throws DocumentException;

    /**
     * Sets the certificate encryption options for this document. An array of one or more public certificates
     * must be provided together with an array of the same size for the permissions for each certificate.
     *  The open permissions for the document can be
     *  AllowPrinting, AllowModifyContents, AllowCopy, AllowModifyAnnotations,
     *  AllowFillIn, AllowScreenReaders, AllowAssembly and AllowDegradedPrinting.
     *  The permissions can be combined by ORing them.
     * Optionally DO_NOT_ENCRYPT_METADATA can be ored to output the metadata in cleartext
     * @param certs the public certificates to be used for the encryption
     * @param permissions the user permissions for each of the certificates
     * @param encryptionType the type of encryption. It can be one of STANDARD_ENCRYPTION_40, STANDARD_ENCRYPTION_128 or ENCRYPTION_AES128.
     * @throws DocumentException if the document is already open
     */
    public void setEncryption(Certificate[] certs, int[] permissions, int encryptionType) throws DocumentException;
}