/*******************************************************************************
 * Copyright 2018 A-SIT Plus GmbH
 * AT-specific eIDAS Connector has been developed in a cooperation between EGIZ, 
 * A-SIT Plus GmbH, 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 "License");
 * You may not use this work except in compliance with the License.
 * You may obtain a copy of the License at:
 * https://joinup.ec.europa.eu/news/understanding-eupl-v12
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * 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.asitplus.eidas.specific.modules.authmodule_eIDASv2.utils;

import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.lang3.StringUtils;
import org.joda.time.DateTime;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.collect.ImmutableList;

import at.asitplus.eidas.specific.modules.authmodule_eIDASv2.Constants;
import at.gv.egiz.eaaf.core.impl.data.Trible;
import eu.eidas.auth.commons.attribute.AttributeDefinition;
import eu.eidas.auth.commons.attribute.AttributeValue;
import eu.eidas.auth.commons.attribute.AttributeValueMarshaller;
import eu.eidas.auth.commons.attribute.AttributeValueMarshallingException;
import eu.eidas.auth.commons.attribute.AttributeValueTransliterator;
import eu.eidas.auth.commons.protocol.eidas.impl.PostalAddress;

public class eIDASResponseUtils {
	private static final Logger log = LoggerFactory.getLogger(eIDASResponseUtils.class);
	
	public static final String PERSONALIDENIFIER_VALIDATION_PATTERN = "^[A-Z,a-z]{2}/[A-Z,a-z]{2}/.*";
	 
	/**
	 * Validate a eIDAS PersonalIdentifier attribute value 
	 * This validation is done according to eIDAS SAML Attribute Profile -  Section 2.2.3 Unique Identifier 
	 * 
	 * @param uniqueID eIDAS attribute value of a unique identifier
	 * @return true if the uniqueID matches to eIDAS to Unique Identifier specification, otherwise false
	 */
	public static boolean validateEidasPersonalIdentifier(String uniqueID) {
		Pattern pattern = Pattern.compile(PERSONALIDENIFIER_VALIDATION_PATTERN );
		Matcher matcher = pattern.matcher(uniqueID);	
		return matcher.matches();
		
	}
	
	
	/**
	 * Parse an eIDAS PersonalIdentifier attribute value into it components. 
	 * This processing is done according to eIDAS SAML Attribute Profile -  Section 2.2.3 Unique Identifier 
	 * 
	 * @param uniqueID eIDAS attribute value of a unique identifier
	 * @return {@link Trible} that contains: 
	 * 				<br> First : citizen country
	 * 				<br> Second: destination country
	 * 				<br> Third : unique identifier
	 * 	<br> or null if the attribute value has a wrong format
	 */					
	public static Trible<String, String, String> parseEidasPersonalIdentifier(String uniqueID) {
		if (!validateEidasPersonalIdentifier(uniqueID)) {
			log.error("eIDAS attribute value for " + Constants.eIDAS_ATTR_PERSONALIDENTIFIER 
					+ " looks wrong formated. Value:" + ((String)uniqueID));				
			return null;
			
		}		
		return Trible.newInstance(uniqueID.substring(0, 2), uniqueID.substring(3, 5), uniqueID.substring(6)); 
		
	}

	//TODO: check possible problem with nonLatinCharacters	
    public static List<String> translateStringListAttribute(AttributeDefinition<?> attributeDefinition, ImmutableList<? extends AttributeValue<?>> attributeValues) {
        final List<String> stringListAttribute = new ArrayList<String>();
        AttributeValueMarshaller<?> attributeValueMarshaller = attributeDefinition.getAttributeValueMarshaller();
        for (AttributeValue<?> attributeValue : attributeValues) {
            String valueString = null;
            try {
            	valueString = attributeValueMarshaller.marshal((AttributeValue) attributeValue);
            	
            	log.trace("Find attr: " + attributeDefinition.getFriendlyName() 
            				+ " with value: " + attributeValue.toString() 
            				+ " nonLatinFlag: " + attributeValue.isNonLatinScriptAlternateVersion()
            				+ " needTransliteration: " + AttributeValueTransliterator.needsTransliteration(valueString));
            	            	
            	//if (attributeValue.isNonLatinScriptAlternateVersion()) {
            	if (!AttributeValueTransliterator.needsTransliteration(valueString)) {
            		stringListAttribute.add(0, valueString);
            		
            	} else {
            		log.trace("Find 'needsTransliteration' flag. Setting this value at last list element ... ");
            		stringListAttribute.add(valueString);
            		
            	}
            	
            } catch (AttributeValueMarshallingException e) {
                throw new IllegalStateException(e);
                
            }
        }
        
        log.trace("Extract values: " + StringUtils.join(stringListAttribute, ",") 
        	+ " for attr: " + attributeDefinition.getFriendlyName());
        
        return stringListAttribute;
        
    }
    
    public static DateTime translateDateAttribute(AttributeDefinition<?> attributeDefinition, ImmutableList<? extends AttributeValue<?>> attributeValues) {
        if (attributeValues.size() != 0) {
            final AttributeValue<?> firstAttributeValue = attributeValues.get(0);
            return (DateTime) firstAttributeValue.getValue();

        }
        
        return null;
    }
    
    public static PostalAddress translateAddressAttribute(AttributeDefinition<?> attributeDefinition, ImmutableList<? extends AttributeValue<?>> attributeValues) {
        final AttributeValue<?> firstAttributeValue = attributeValues.get(0);
        return (PostalAddress) firstAttributeValue.getValue();

    }
	
}