/*
 * 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.service;

import java.io.File;
import java.text.MessageFormat;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.annotation.PostConstruct;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import at.asitplus.eidas.specific.modules.auth.eidas.v2.Constants;
import at.gv.egiz.eaaf.core.api.idp.IConfigurationWithSP;
import at.gv.egiz.eaaf.core.exceptions.EaafConfigurationException;
import at.gv.egiz.eaaf.core.impl.utils.KeyValueUtils;
import edu.umd.cs.findbugs.annotations.NonNull;
import eu.eidas.auth.commons.attribute.AttributeRegistries;
import eu.eidas.auth.commons.attribute.AttributeRegistry;

@Service("attributeRegistry")
public class EidasAttributeRegistry {
  private static final Logger log = LoggerFactory.getLogger(EidasAttributeRegistry.class);
  @Autowired
  private IConfigurationWithSP basicConfig;

  private AttributeRegistry coreAttributeRegistry;

  private String eidasAttributesFile;
  private String additionalAttributesFile;

  @PostConstruct
  private void initialize() throws RuntimeException {
    try {
      if (eidasAttributesFile.isEmpty()) {
        log.error("Basic eIDAS addribute definition NOT defined");
        throw new EaafConfigurationException("config.30",
            new Object[] { "eidas-attributes.xml" });

      }

      boolean additionalAttrAvailabe = false;
      if (!additionalAttributesFile.isEmpty()) {
        final File file = new File(additionalAttributesFile);
        if (file.exists()) {
          additionalAttrAvailabe = true;
        }

      }

      if (!additionalAttrAvailabe) {
        log.info("Start eIDAS ref. impl. Core without additional eIDAS attribute definitions ... ");
        coreAttributeRegistry = AttributeRegistries.fromFiles(eidasAttributesFile, null);

      } else {
        // load attribute definitions
        log.info("Start eIDAS ref. impl. Core with additional eIDAS attribute definitions ... ");
        coreAttributeRegistry = AttributeRegistries.fromFiles(eidasAttributesFile, null,
            additionalAttributesFile);

      }

    } catch (final Throwable e) {
      log.error("Can NOT initialize eIDAS attribute definition.", e);
      throw new RuntimeException("Can NOT initialize eIDAS attribute definition.", e);

    }
  }

  public AttributeRegistry getCoreAttributeRegistry() {
    return coreAttributeRegistry;
  }

  /**
   * Get Map of attributes that are requested by default.
   * 
   * @return Map of AttributeIdentifier, isRequired flag
   */
  @NonNull
  public Map<String, Boolean> getDefaultAttributeSetFromConfiguration() {
    /*
     * TODO: select set for representation if mandates should be used. It's an open
     * task in respect to requested eIDAS attributes and isRequired flag, because
     * there can be a decision problem in case of natural or legal person
     * representation! From an Austrian use-case point of view, an Austrian service
     * provider can support mandates for natural and legal persons at the same time.
     * However, we CAN NOT request attributes for natural AND legal persons on the
     * same time, because it's not possible to represent both simultaneously.
     */
    final Map<String, String> configAttributes =
        basicConfig.getBasicConfigurationWithPrefix(
            Constants.CONIG_PROPS_EIDAS_NODE_ATTRIBUTES_REQUESTED_DEFAULT_ONLYNATURAL);
    return processAttributeInfosFromConfig(configAttributes);

  }

  /**
   * Get a Map of attributes that are additionally requested for a specific country.
   * 
   * @param countryCode Country Code
   * @return Map of AttributeIdentifier, isRequired flag
   */
  @NonNull
  public Map<String, Boolean> getAttributeSetFromConfiguration(String countryCode) {

    /*
     * TODO: select set for representation if mandates should be used. It's an open
     * task in respect to requested eIDAS attributes and isRequired flag, because
     * there can be a decision problem in case of natural or legal person
     * representation! From an Austrian use-case point of view, an Austrian service
     * provider can support mandates for natural and legal persons at the same time.
     * However, we CAN NOT request attributes for natural AND legal persons on the
     * same time, because it's not possible to represent both simultaneously.
     */
    final Map<String, String> configAttributes =
        basicConfig.getBasicConfigurationWithPrefix(
            MessageFormat.format(
                Constants.CONIG_PROPS_EIDAS_NODE_ATTRIBUTES_REQUESTED_CC_SPECIFIC_ONLYNATURAL,
                countryCode.toLowerCase()));
    return processAttributeInfosFromConfig(configAttributes);

  }

  private Map<String, Boolean> processAttributeInfosFromConfig(Map<String, String> configAttributes) {

    final Map<String, Boolean> result = new HashMap<>();
    for (final String el : configAttributes.values()) {
      if (StringUtils.isNotEmpty(el.trim())) {
        final List<String> attrDef = KeyValueUtils.getListOfCsvValues(el.trim());
        boolean isRequired = false;
        if (attrDef.size() == 2) {
          isRequired = Boolean.parseBoolean(attrDef.get(1));
        }

        result.put(attrDef.get(0), isRequired);

      }
    }

    log.trace("Load #" + result.size() + " requested attributes from configuration");
    return result;

  }

  public void setEidasAttributesFile(String eidasAttributesFile) {
    this.eidasAttributesFile = eidasAttributesFile;
  }

  public void setAdditionalAttributesFile(String additionalAttributesFile) {
    this.additionalAttributesFile = additionalAttributesFile;
  }

}