/*
 * 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.auth.eidas.v2.utils;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.annotation.Nullable;

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 com.google.common.collect.ImmutableSet;

import at.asitplus.eidas.specific.modules.auth.eidas.v2.Constants;
import at.asitplus.eidas.specific.modules.auth.eidas.v2.exception.EidasAttributeException;
import at.gv.e_government.reference.namespace.persondata._20020228.PostalAddressType;
import at.gv.egiz.eaaf.core.impl.data.Triple;
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) {
    final Pattern pattern = Pattern.compile(PERSONALIDENIFIER_VALIDATION_PATTERN);
    final 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 Triple} 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 Triple<String, String, String> parseEidasPersonalIdentifier(String uniqueID) {
    if (!validateEidasPersonalIdentifier(uniqueID)) {
      log.error("eIDAS attribute value for {} looks wrong formated. Value: {}",
          Constants.eIDAS_ATTR_PERSONALIDENTIFIER, uniqueID);
      return null;

    }
    return Triple.newInstance(uniqueID.substring(0, 2), uniqueID.substring(3, 5), uniqueID.substring(6));
  }

  /**
   * Get eIDAS attribute-values from eIDAS Node attributes.
   *
   * @param attributeDefinition eIDAS attribute definition
   * @param attributeValues     Attributes from eIDAS response
   * @return Set of attribute values. If more then one value than the first value
   *         contains the 'Latin' value.
   */
  // TODO: check possible problem with nonLatinCharacters
  public static List<String> translateStringListAttribute(AttributeDefinition<?> attributeDefinition,
      @Nullable ImmutableSet<? extends AttributeValue<?>> attributeValues) {
    final List<String> stringListAttribute = new ArrayList<>();
    if (attributeValues == null) {
      log.info("Can not extract infos from 'null' attribute value");

    } else {
      final AttributeValueMarshaller<?> attributeValueMarshaller =
          attributeDefinition.getAttributeValueMarshaller();
      for (final AttributeValue<?> attributeValue : attributeValues) {
        String valueString = null;
        try {
          valueString = attributeValueMarshaller.marshal((AttributeValue) attributeValue);

          log.trace("Find attr: {} with value: {} nonLatinFlag: {} needTransliteration: {}",
              attributeDefinition.getFriendlyName(), attributeValue.toString(),
              attributeValue.isNonLatinScriptAlternateVersion(),
              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);

            log.trace("Find attr: {} with value: {} nonLatinFlag: {} needTransliteration: {}",
                attributeDefinition.getFriendlyName(), attributeValue.toString(),
                attributeValue.isNonLatinScriptAlternateVersion(),
                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 (final AttributeValueMarshallingException e) {
          throw new IllegalStateException(e);

        }

      }
      log.trace("Extract values: {} for attr: {}",
          StringUtils.join(stringListAttribute, ","), attributeDefinition.getFriendlyName());

    }

    return stringListAttribute;

  }


  /**
   * Convert eIDAS DateTime attribute to Java Object.
   *
   * @param attributeDefinition eIDAS attribute definition.
   * @param attributeValues     eIDAS attribute value
   * @return
   */
  @Nullable
  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;
  }

  /**
   * Concert eIDAS Address attribute to Java object.
   *
   * @param attributeDefinition eIDAS attribute definition
   * @param attributeValues     eIDAS attribute value
   * @return
   */
  @Nullable
  public static PostalAddress translateAddressAttribute(AttributeDefinition<?> attributeDefinition,
                                                        ImmutableList<? extends AttributeValue<?>> attributeValues) {
    final AttributeValue<?> firstAttributeValue = attributeValues.get(0);
    return (PostalAddress) firstAttributeValue.getValue();
  }

  /**
   * Post-Process the eIDAS CurrentAddress attribute.
   *
   * @param currentAddressObj eIDAS current address information
   * @return current address or null if no attribute is available
   * @throws EidasAttributeException if eIDAS attribute is of a wrong type
   */
  public static PostalAddressType processAddress(Object currentAddressObj) throws EidasAttributeException {
    if (currentAddressObj != null) {
      if (currentAddressObj instanceof PostalAddress) {
        final PostalAddressType result = new PostalAddressType();
        result.setPostalCode(((PostalAddress) currentAddressObj).getPostCode());
        result.setMunicipality(((PostalAddress) currentAddressObj).getPostName());
        // TODO: add more mappings
        return result;
      } else {
        log.warn("eIDAS attr: " + Constants.eIDAS_ATTR_CURRENTADDRESS + " is of WRONG type");
        throw new EidasAttributeException(Constants.eIDAS_ATTR_CURRENTADDRESS);
      }
    } else {
      log.debug("NO '" + Constants.eIDAS_ATTR_CURRENTADDRESS + "' attribute. Post-Processing skipped ... ");
    }
    return null;
  }

  /**
   * Post-Process the eIDAS BirthName attribute.
   *
   * @param birthNameObj eIDAS birthname information
   * @return birthName or null if no attribute is available
   * @throws EidasAttributeException if eIDAS attribute is of a wrong type
   */
  public static String processBirthName(Object birthNameObj) throws EidasAttributeException {
    if (birthNameObj != null) {
      if (birthNameObj instanceof String) {
        return (String) birthNameObj;
      } else {
        log.warn("eIDAS attr: " + Constants.eIDAS_ATTR_BIRTHNAME + " is of WRONG type");
        throw new EidasAttributeException(Constants.eIDAS_ATTR_BIRTHNAME);
      }
    } else {
      log.debug("NO '" + Constants.eIDAS_ATTR_BIRTHNAME + "' attribute. Post-Processing skipped ... ");
    }
    return null;
  }

  /**
   * Post-Process the eIDAS PlaceOfBirth attribute.
   *
   * @param placeOfBirthObj eIDAS Place-of-Birth information
   * @return place of Birth or null if no attribute is available
   * @throws EidasAttributeException if eIDAS attribute is of a wrong type
   */
  public static String processPlaceOfBirth(Object placeOfBirthObj) throws EidasAttributeException {
    if (placeOfBirthObj != null) {
      if (placeOfBirthObj instanceof String) {
        return (String) placeOfBirthObj;

      } else {
        log.warn("eIDAS attr: " + Constants.eIDAS_ATTR_PLACEOFBIRTH + " is of WRONG type");
        throw new EidasAttributeException(Constants.eIDAS_ATTR_PLACEOFBIRTH);

      }

    } else {
      log.debug("NO '" + Constants.eIDAS_ATTR_PLACEOFBIRTH + "' attribute. Post-Processing skipped ... ");
    }
    return null;
  }

  /**
   * Post-Process the eIDAS DateOfBirth attribute.
   *
   * @param dateOfBirthObj eIDAS date-of-birth attribute information
   * @return formated user's date-of-birth
   * @throws EidasAttributeException if NO attribute is available
   */
  public static DateTime processDateOfBirth(Object dateOfBirthObj) throws EidasAttributeException {
    if (!(dateOfBirthObj instanceof DateTime)) {
      throw new EidasAttributeException(Constants.eIDAS_ATTR_DATEOFBIRTH);
    }
    return (DateTime) dateOfBirthObj;
  }

  /**
   * Post-Process the eIDAS DateOfBirth attribute to a string.
   *
   * @param dateOfBirthObj eIDAS date-of-birth attribute information
   * @return formated user's date-of-birth as string
   * @throws EidasAttributeException if NO attribute is available
   */
  public static String processDateOfBirthToString(Object dateOfBirthObj) throws EidasAttributeException {
    if (dateOfBirthObj instanceof String) {
      try {
        new SimpleDateFormat("yyyy-MM-dd").parse((String) dateOfBirthObj);
        return (String) dateOfBirthObj;
      } catch (ParseException e) {
        throw new EidasAttributeException(Constants.eIDAS_ATTR_DATEOFBIRTH);
      }
    }
    if (!(dateOfBirthObj instanceof DateTime)) {
      throw new EidasAttributeException(Constants.eIDAS_ATTR_DATEOFBIRTH);
    }
    return new SimpleDateFormat("yyyy-MM-dd").format(((DateTime) dateOfBirthObj).toDate());
  }

  /**
   * Post-Process the eIDAS GivenName attribute.
   *
   * @param givenNameObj eIDAS givenName attribute information
   * @return formated user's givenname
   * @throws EidasAttributeException if NO attribute is available
   */
  public static String processGivenName(Object givenNameObj) throws EidasAttributeException {
    if (!(givenNameObj instanceof String)) {
      throw new EidasAttributeException(Constants.eIDAS_ATTR_CURRENTGIVENNAME);
    }
    return (String) givenNameObj;
  }

  /**
   * Post-Process the eIDAS FamilyName attribute.
   *
   * @param familyNameObj eIDAS familyName attribute information
   * @return formated user's familyname
   * @throws EidasAttributeException if NO attribute is available
   */
  public static String processFamilyName(Object familyNameObj) throws EidasAttributeException {
    if (!(familyNameObj instanceof String)) {
      throw new EidasAttributeException(Constants.eIDAS_ATTR_CURRENTFAMILYNAME);
    }
    return (String) familyNameObj;
  }

  /**
   * Post-Process the eIDAS personal identifier attribute.
   *
   * @param personalIdentifierObj eIDAS personal identifier attribute-information
   * @return formated user's full personal identifier
   * @throws EidasAttributeException if NO attribute is available
   */
  public static String processPersonalIdentifier(Object personalIdentifierObj) throws EidasAttributeException {
    if (!(personalIdentifierObj instanceof String)) {
      throw new EidasAttributeException(Constants.eIDAS_ATTR_PERSONALIDENTIFIER);
    }
    return (String) personalIdentifierObj;
  }
  
  
  /**
   * Post-Process the eIDAS pseudonym to ERnB unique identifier.
   *
   * @param personalIdObj eIDAS PersonalIdentifierAttribute
   * @return Unique personal identifier without country-code information
   * @throws EidasAttributeException if NO attribute is available
   */
  public static String processPseudonym(Object personalIdObj) throws EidasAttributeException {
    if (!(personalIdObj instanceof String)) {
      throw new EidasAttributeException(Constants.eIDAS_ATTR_PERSONALIDENTIFIER);
    }
    final Triple<String, String, String> eIdentifier =
        EidasResponseUtils.parseEidasPersonalIdentifier((String) personalIdObj);
    if (eIdentifier == null || eIdentifier.getThird() == null) {
      throw new EidasAttributeException("Error processing eIdentifier");
    }
    return eIdentifier.getThird();
  }

  /**
   * Post-Process the eIDAS pseudonym to citizen country code.
   *
   * @param personalIdObj eIDAS PersonalIdentifierAttribute
   * @return Citizen Country Code
   * @throws EidasAttributeException if NO attribute is available
   */
  public static String processCountryCode(Object personalIdObj) throws EidasAttributeException {
    if (!(personalIdObj instanceof String)) {
      throw new EidasAttributeException(Constants.eIDAS_ATTR_PERSONALIDENTIFIER);
    }
    final Triple<String, String, String> eIdentifier =
        EidasResponseUtils.parseEidasPersonalIdentifier((String) personalIdObj);
    if (eIdentifier == null || eIdentifier.getFirst() == null) {
      throw new EidasAttributeException("Error processing eIdentifier");
    }
    return eIdentifier.getFirst();
  }

  /**
   * Post-Process the eIDAS TaxReference attribute.
   *
   * @param taxReferenceObj eIDAS TaxReference attribute information
   * @return formated user's TaxReference
   * @throws EidasAttributeException if NO attribute is available
   */
  public static String processTaxReference(Object taxReferenceObj) throws EidasAttributeException {
    if (!(taxReferenceObj instanceof String)) {
      throw new EidasAttributeException(Constants.eIDAS_ATTR_TAXREFERENCE);
    }
    return (String) taxReferenceObj;
  }
}