/*
 * DSS - Digital Signature Services
 *
 * Copyright (C) 2013 European Commission, Directorate-General Internal Market and Services (DG MARKT), B-1049 Bruxelles/Brussel
 *
 * Developed by: 2013 ARHS Developments S.A. (rue Nicolas Bové 2B, L-1253 Luxembourg) http://www.arhs-developments.com
 *
 * This file is part of the "DSS - Digital Signature Services" project.
 *
 * "DSS - Digital Signature Services" is free software: you can redistribute it and/or modify it under the terms of
 * the GNU Lesser General Public License as published by the Free Software Foundation, either version 2.1 of the
 * License, or (at your option) any later version.
 *
 * DSS 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 Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with
 * "DSS - Digital Signature Services".  If not, see <http://www.gnu.org/licenses/>.
 */

package eu.europa.ec.markt.dss.signature.xades;

import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

import eu.europa.ec.markt.dss.DSSXMLUtils;
import eu.europa.ec.markt.dss.XAdESNamespaces;
import eu.europa.ec.markt.dss.exception.DSSException;
import eu.europa.ec.markt.dss.validation102853.CertificateVerifier;
import eu.europa.ec.markt.dss.validation102853.xades.XAdESSignature;

public abstract class ExtensionBuilder extends XAdESBuilder {

	/*
	 * This object allows to access DOM signature representation using XPATH
	 */
	protected XAdESSignature xadesSignature;

	/**
	 * This field represents the current signature being extended.
	 */
	protected Element currentSignatureDom;

	/**
	 * This field represents the signature qualifying properties
	 */
	protected Element qualifyingPropertiesDom;

	/**
	 * This field represents the unsigned properties
	 */
	protected Element unsignedPropertiesDom;

	/**
	 * This field contains unsigned signature properties
	 */
	protected Element unsignedSignaturePropertiesDom;

	/**
	 * This field represents the signed properties
	 */
	protected Element signedPropertiesDom;

	/**
	 * This field contains signed data object properties
	 */
	protected Element signedDataObjectPropertiesDom;

	protected ExtensionBuilder(final CertificateVerifier certificateVerifier) {
		super(certificateVerifier);
	}

	/**
	 * Returns or creates (if it does not exist) the UnsignedPropertiesType DOM object.
	 *
	 * @return
	 * @throws DSSException
	 */
	protected void ensureUnsignedProperties() throws DSSException {

		final NodeList qualifyingPropertiesNodeList = currentSignatureDom.getElementsByTagNameNS(XAdESNamespaces.XAdES, "QualifyingProperties");
		if (qualifyingPropertiesNodeList.getLength() != 1) {

			throw new DSSException("The signature does not contain QualifyingProperties element (or contains more than one)! Extension is not possible.");
		}

		qualifyingPropertiesDom = (Element) qualifyingPropertiesNodeList.item(0);

		final NodeList unsignedPropertiesNodeList = currentSignatureDom.getElementsByTagNameNS(XAdESNamespaces.XAdES, "UnsignedProperties");
		final int length = unsignedPropertiesNodeList.getLength();
		if (length == 1) {

			unsignedPropertiesDom = (Element) qualifyingPropertiesNodeList.item(0);
		} else if (length == 0) {

			unsignedPropertiesDom = DSSXMLUtils.addElement(documentDom, qualifyingPropertiesDom, XAdESNamespaces.XAdES, "xades:UnsignedProperties");
		} else {

			throw new DSSException("The signature contains more then one UnsignedProperties element! Extension is not possible.");
		}
	}

	/**
	 * Returns or creates (if it does not exist) the UnsignedSignaturePropertiesType DOM object.
	 *
	 * @return
	 * @throws DSSException
	 */
	protected void ensureUnsignedSignatureProperties() throws DSSException {

		final NodeList unsignedSignaturePropertiesNodeList = currentSignatureDom.getElementsByTagNameNS(XAdESNamespaces.XAdES, "UnsignedSignatureProperties");
		final int length = unsignedSignaturePropertiesNodeList.getLength();
		if (length == 1) {

			unsignedSignaturePropertiesDom = (Element) unsignedSignaturePropertiesNodeList.item(0);
		} else if (length == 0) {

			unsignedSignaturePropertiesDom = DSSXMLUtils.addElement(documentDom, unsignedPropertiesDom, XAdESNamespaces.XAdES, "xades:UnsignedSignatureProperties");
		} else {

			throw new DSSException("The signature contains more then one UnsignedSignatureProperties element! Extension is not possible.");
		}
	}

	/**
	 * Returns or create (if it does not exist) the SignedDataObjectProperties DOM object.
	 *
	 * @throws DSSException
	 */
	protected void ensureSignedDataObjectProperties() throws DSSException {

		final NodeList signedDataObjectPropertiesNodeList = currentSignatureDom.getElementsByTagNameNS(XAdESNamespaces.XAdES, "SignedDataObjectProperties");
		final int length = signedDataObjectPropertiesNodeList.getLength();
		if (length == 1) {

			signedDataObjectPropertiesDom = (Element) signedDataObjectPropertiesNodeList.item(0);
		} else if (length == 0) {

			signedDataObjectPropertiesDom = DSSXMLUtils.addElement(documentDom, signedPropertiesDom, XAdESNamespaces.XAdES, "xades:SignedDataObjectProperties");
		} else {

			throw new DSSException("The signature contains more than one SignedDataObjectProperties element! Extension is not possible.");
		}
	}
}