/*
 * Copyright 2014 Federal Chancellery Austria
 * MOA-ID has been developed in a cooperation between BRZ, the Federal
 * Chancellery Austria - ICT staff unit, and Graz University of Technology.
 *
 * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by
 * the European Commission - subsequent versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 * http://www.osor.eu/eupl/
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the Licence is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing permissions and
 * limitations under the Licence.
 *
 * This product combines work with different licenses. See the "NOTICE" text
 * file for details on the various modules and licenses.
 * The "NOTICE" text file is part of the distribution. Any derivative works
 * that you distribute must include a readable copy of the "NOTICE" text file.
 */
package at.gv.egovernment.moa.id.protocols.pvp2x.builder;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.joda.time.DateTime;
import org.opensaml.Configuration;
import org.opensaml.saml2.core.Attribute;
import org.opensaml.saml2.core.AttributeQuery;
import org.opensaml.saml2.core.Issuer;
import org.opensaml.saml2.core.NameID;
import org.opensaml.saml2.core.Subject;
import org.opensaml.saml2.core.impl.AttributeQueryBuilder;
import org.opensaml.xml.io.Marshaller;
import org.opensaml.xml.io.MarshallingException;
import org.opensaml.xml.security.x509.X509Credential;
import org.opensaml.xml.signature.Signature;
import org.opensaml.xml.signature.SignatureConstants;
import org.opensaml.xml.signature.SignatureException;
import org.opensaml.xml.signature.Signer;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.w3c.dom.Document;

import at.gv.egiz.eaaf.modules.pvp2.exception.AttributQueryException;
import at.gv.egiz.eaaf.modules.pvp2.exception.CredentialsNotAvailableException;
import at.gv.egiz.eaaf.modules.pvp2.impl.builder.PVPAttributeBuilder;
import at.gv.egiz.eaaf.modules.pvp2.impl.builder.SamlAttributeGenerator;
import at.gv.egiz.eaaf.modules.pvp2.impl.utils.SAML2Utils;
import at.gv.egovernment.moa.id.commons.api.IOAAuthParameters;
import at.gv.egovernment.moa.id.commons.api.exceptions.ConfigurationException;
import at.gv.egovernment.moa.id.protocols.pvp2x.PVPConstants;
import at.gv.egovernment.moa.id.protocols.pvp2x.signer.IDPCredentialProvider;
import at.gv.egovernment.moa.logging.Logger;

/**
 * @author tlenz
 *
 */
@Service("AttributQueryBuilder")
public class AttributQueryBuilder {

	@Autowired IDPCredentialProvider credentialProvider;
	
	public List<Attribute> buildSAML2AttributeList(IOAAuthParameters oa, Iterator<String> iterator) throws ConfigurationException {
		
		Logger.debug("Build OA specific Attributes for AttributQuery request");
		
		List<Attribute> attrList = new ArrayList<Attribute>();
		
		SamlAttributeGenerator generator = new SamlAttributeGenerator();
		
		while(iterator.hasNext()) {			
			String rA = iterator.next();			
			Attribute attr = PVPAttributeBuilder.buildEmptyAttribute(rA);
			if (attr == null) {
				Logger.warn("Attribut " + rA + " has no valid Name");
				
			} else {				
				//add OA specific information
				if (rA.equals(PVPConstants.EID_SECTOR_FOR_IDENTIFIER_NAME)) {
					attr = generator.buildStringAttribute(attr.getFriendlyName(), 
								attr.getName(), oa.getAreaSpecificTargetIdentifier());					
					
				}
				
				//TODO: add attribute values for SSO with mandates (ProfileList)
								
				attrList.add(attr);
			}			
		}
		
		return attrList;
	}
	
	
	public AttributeQuery buildAttributQueryRequest(String spEntityID, String nameID, 
			String endpoint, List<Attribute> requestedAttributes) throws AttributQueryException {
		
		
		try { 
		
			AttributeQuery query = new AttributeQueryBuilder().buildObject();
		
			//set user nameID
			Subject subject = SAML2Utils.createSAMLObject(Subject.class);
			NameID subjectNameID = SAML2Utils.createSAMLObject(NameID.class);				
			subjectNameID.setValue(nameID);
			subjectNameID.setFormat(NameID.TRANSIENT);
			subject.setNameID(subjectNameID);				
			query.setSubject(subject);
			
			//set attributes
			query.getAttributes().addAll(requestedAttributes);
			
			//set general request parameters
			DateTime now = new DateTime();
			query.setIssueInstant(now);
			
			Issuer nissuer = SAML2Utils.createSAMLObject(Issuer.class);
			nissuer.setValue(spEntityID);
			nissuer.setFormat(NameID.ENTITY);
			query.setIssuer(nissuer);
			
			String sessionID = SAML2Utils.getSecureIdentifier();
			query.setID(sessionID);
	
			query.setDestination(endpoint);
			
			X509Credential idpSigningCredential = credentialProvider.getIDPAssertionSigningCredential();
			
			Signature signer = SAML2Utils.createSAMLObject(Signature.class);
			signer.setSignatureAlgorithm(SignatureConstants.ALGO_ID_SIGNATURE_RSA_SHA1);
			signer.setCanonicalizationAlgorithm(SignatureConstants.ALGO_ID_C14N_EXCL_OMIT_COMMENTS);
			signer.setSigningCredential(idpSigningCredential);
			query.setSignature(signer);
	
			DocumentBuilder builder;
			DocumentBuilderFactory factory = DocumentBuilderFactory
					.newInstance();
	
			builder = factory.newDocumentBuilder();
			Document document = builder.newDocument();
			Marshaller out = Configuration.getMarshallerFactory()
					.getMarshaller(query);
			out.marshall(query, document);
	
			Signer.signObject(signer);
			
			return query;
			
		} catch (CredentialsNotAvailableException e) {
			Logger.error("Build AttributQuery Request FAILED.", e);
			throw new AttributQueryException("Build AttributQuery Request FAILED.", null, e);
			
		} catch (ParserConfigurationException e) {
			Logger.error("Build AttributQuery Request FAILED.", e);
			throw new AttributQueryException("Build AttributQuery Request FAILED.", null, e);
			
		} catch (MarshallingException e) {
			Logger.error("Build AttributQuery Request FAILED.", e);
			throw new AttributQueryException("Build AttributQuery Request FAILED.", null, e);
			
		} catch (SignatureException e) {
			Logger.error("Build AttributQuery Request FAILED.", e);
			throw new AttributQueryException("Build AttributQuery Request FAILED.", null, e);
			
		}
				
				
	}
	
}