/*
 * 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.handler;

import java.io.UnsupportedEncodingException;
import java.util.Base64;
import java.util.Map;

import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Hex;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import at.asitplus.eidas.specific.modules.auth.eidas.v2.Constants;
import at.asitplus.eidas.specific.modules.auth.eidas.v2.exception.EidPostProcessingException;
import at.asitplus.eidas.specific.modules.auth.eidas.v2.exception.EidasAttributeException;
import at.asitplus.eidas.specific.modules.auth.eidas.v2.utils.EidasResponseUtils;
import at.gv.egiz.eaaf.core.impl.data.Trible;

public class DeEidProcessor extends AbstractEidProcessor {
  private static final Logger log = LoggerFactory.getLogger(DeEidProcessor.class);
  private static final String canHandleCC = "DE";

  private int priority = 1;

  @Override
  public int getPriority() {
    return priority;
  }

  @Override
  public boolean canHandle(String countryCode) {
    return countryCode != null && countryCode.equalsIgnoreCase(canHandleCC);

  }

  public void setPriority(int priority) {
    this.priority = priority;
  }

  @Override
  public String getName() {
    return "DE-PostProcessor";

  }

  @Override
  protected String processPseudonym(Object uniqeIdentifierObj) throws EidPostProcessingException,
      EidasAttributeException {
    if (uniqeIdentifierObj == null || !(uniqeIdentifierObj instanceof String)) {
      throw new EidasAttributeException(Constants.eIDAS_ATTR_PERSONALIDENTIFIER);
    }

    final Trible<String, String, String> eIdentifier =
        EidasResponseUtils.parseEidasPersonalIdentifier((String) uniqeIdentifierObj);

    log.trace(getName() + " starts processing of attribute: " + Constants.eIDAS_ATTR_PERSONALIDENTIFIER);
    final String result = convertDeIdentifier(eIdentifier.getThird());
    log.debug(getName() + " finished processing of attribute: " + Constants.eIDAS_ATTR_PERSONALIDENTIFIER);

    return result;

  }

  private String convertDeIdentifier(String hexEncodedDeIdentifier) throws EidPostProcessingException {
    if (hexEncodedDeIdentifier.length() != 64) {
      throw new EidPostProcessingException("ernb.03", new Object[] {
          "Input has wrong length, expected 64 chars" });
    }

    byte[] data;
    try {
      data = Hex.decodeHex(hexEncodedDeIdentifier);
      final byte[] encoded = Base64.getEncoder().encode(data);
      return new String(encoded, "UTF-8");

    } catch (final DecoderException | UnsupportedEncodingException e) {
      throw new EidPostProcessingException("ernb.03", null, e);

    }

    
  }

  @Override
  protected Map<String, Boolean> getCountrySpecificRequestedAttributes() {
    return attrRegistry.getAttributeSetFromConfiguration(canHandleCC);

  }

}