/*******************************************************************************
 * Copyright 2017 Graz University of Technology
 * EAAF-Core Components has been developed in a cooperation between EGIZ,  
 * A-SIT+, A-SIT, and Graz University of Technology.
 *
 * Licensed under the EUPL, Version 1.2 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:
 * https://joinup.ec.europa.eu/news/understanding-eupl-v12
 *
 * 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.egiz.eaaf.modules.pvp2.impl.utils;

import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import at.gv.egiz.eaaf.core.api.data.EAAFConstants;
import at.gv.egiz.eaaf.modules.pvp2.exception.QAANotAllowedException;

/**
 * @author tlenz
 *
 */
public class QAALevelVerifier {

	private static final Logger log = LoggerFactory.getLogger(QAALevelVerifier.class);
	
	private static boolean verifyQAALevel(String qaaAuth, String requiredLoA, String matchingMode) throws QAANotAllowedException {
		//to MINIMUM machting
		if (EAAFConstants.EIDAS_LOA_MATCHING_MINIMUM.equals(matchingMode)) {
			log.trace("Perfom LoA matching in 'MINIMUM' mode ... ");
			if (EAAFConstants.EIDAS_LOA_LOW.equals(requiredLoA) && 
					(EAAFConstants.EIDAS_LOA_LOW.equals(qaaAuth) || 
						EAAFConstants.EIDAS_LOA_SUBSTANTIAL.equals(qaaAuth) ||
								EAAFConstants.EIDAS_LOA_HIGH.equals(qaaAuth))
					)  
				return true;
	
			else if (EAAFConstants.EIDAS_LOA_SUBSTANTIAL.equals(requiredLoA) && 
					(EAAFConstants.EIDAS_LOA_SUBSTANTIAL.equals(qaaAuth) ||
							EAAFConstants.EIDAS_LOA_HIGH.equals(qaaAuth))
					) 
				return true;
	
			else if (EAAFConstants.EIDAS_LOA_HIGH.equals(requiredLoA) && EAAFConstants.EIDAS_LOA_HIGH.equals(qaaAuth)) 
				return true;
								
		} else if (EAAFConstants.EIDAS_LOA_MATCHING_EXACT.equals(matchingMode)) {
			//to EXACT matching
			log.trace("Perfom LoA matching in 'EXACT' mode ... ");
			if (qaaAuth.equals(requiredLoA)) { 
				log.debug("Required LoA fits LoA from authentication. Continue auth process ... ");
				return true;
						
			}
																	
		} else {
			log.warn("LoA matching-mode:" + matchingMode + " is NOT supported by this implementation");
			throw new QAANotAllowedException(qaaAuth, requiredLoA, matchingMode);
			
		}
		
		return false;
	
	}		
	
	public static void verifyQAALevel(String qaaAuth, List<String> requiredLoAs, String matchingMode) throws QAANotAllowedException {
		boolean hasMatch = false;
		for (String loa : requiredLoAs) {
			if (verifyQAALevel(qaaAuth, loa, matchingMode))
				hasMatch = true;
							
		}		
		
		if (!hasMatch)
			throw new QAANotAllowedException(qaaAuth, requiredLoAs.toArray().toString(), matchingMode);
		
		else
			log.debug("Requesed LoA fits LoA from authentication. Continue auth process ... ");
		
	}
}