/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    *
   *   http://www.apache.org/licenses/LICENSE-2.0
   *
   * 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.
   */
  package org.apache.syncope.wa.starter.saml.idp.metadata;
  
  import com.github.benmanes.caffeine.cache.Cache;
  import java.nio.charset.StandardCharsets;
  import java.util.Base64;
  import java.util.Optional;
  import org.apache.syncope.common.lib.SyncopeClientException;
  import org.apache.syncope.common.lib.to.SAML2IdPEntityTO;
  import org.apache.syncope.common.lib.types.ClientExceptionType;
  import org.apache.syncope.common.rest.api.service.SAML2IdPEntityService;
  import org.apache.syncope.wa.bootstrap.WARestClient;
  import org.apereo.cas.support.saml.idp.metadata.locator.AbstractSamlIdPMetadataLocator;
  import org.apereo.cas.support.saml.services.SamlRegisteredService;
  import org.apereo.cas.support.saml.services.idp.metadata.SamlIdPMetadataDocument;
  import org.apereo.cas.util.crypto.CipherExecutor;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  public class WASamlIdPMetadataLocator extends AbstractSamlIdPMetadataLocator {
  
      protected static final Logger LOG = LoggerFactory.getLogger(WASamlIdPMetadataLocator.class);
  
      protected final WARestClient waRestClient;
  
      public WASamlIdPMetadataLocator(
              final CipherExecutor<String, String> metadataCipherExecutor,
              final Cache<String, SamlIdPMetadataDocument> metadataCache,
              final WARestClient waRestClient) {
  
          super(metadataCipherExecutor, metadataCache);
          this.waRestClient = waRestClient;
      }
  
      protected SAML2IdPEntityTO fetchFromCore(final Optional<SamlRegisteredService> registeredService) {
          SAML2IdPEntityService idpEntityService = waRestClient.getService(SAML2IdPEntityService.class);
  
          SAML2IdPEntityTO result = null;
          try {
              result = idpEntityService.get(registeredService.
                      map(SamlRegisteredService::getName).
                      orElse(SAML2IdPEntityService.DEFAULT_OWNER));
          } catch (SyncopeClientException e) {
              if (e.getType() == ClientExceptionType.NotFound && registeredService.isPresent()) {
                  result = idpEntityService.get(SAML2IdPEntityService.DEFAULT_OWNER);
              } else {
                  throw e;
              }
          }
  
          return result;
      }
  
      @Override
      public SamlIdPMetadataDocument fetchInternal(final Optional<SamlRegisteredService> registeredService) {
          try {
              LOG.info("Locating SAML2 IdP metadata document");
  
              SAML2IdPEntityTO entityTO = fetchFromCore(registeredService);
              if (entityTO != null) {
                  SamlIdPMetadataDocument document = new SamlIdPMetadataDocument();
                  document.setAppliesTo(entityTO.getKey());
                  document.setMetadata(new String(Base64.getDecoder().decode(
                          entityTO.getMetadata()), StandardCharsets.UTF_8));
                  if (entityTO.getSigningCertificate() != null) {
                      document.setSigningCertificate(new String(Base64.getDecoder().decode(
                              entityTO.getSigningCertificate()), StandardCharsets.UTF_8));
                  }
                  if (entityTO.getSigningKey() != null) {
                      document.setSigningKey(new String(Base64.getDecoder().decode(
                              entityTO.getSigningKey().getBytes(StandardCharsets.UTF_8)), StandardCharsets.UTF_8));
                  }
                  if (entityTO.getEncryptionCertificate() != null) {
                      document.setEncryptionCertificate(new String(Base64.getDecoder().decode(
                              entityTO.getEncryptionCertificate()), StandardCharsets.UTF_8));
                  }
                  if (entityTO.getEncryptionKey() != null) {
                      document.setEncryptionKey(new String(Base64.getDecoder().decode(
                              entityTO.getEncryptionKey().getBytes(StandardCharsets.UTF_8)), StandardCharsets.UTF_8));
                  }
  
                  if (document.isValid()) {
                     LOG.debug("Found SAML2 IdP metadata document: {}", document.getId());
                     return document;
                 }
             }
 
             LOG.warn("Not a valid SAML2 IdP metadata document");
             return null;
         } catch (Exception e) {
             if (e instanceof SyncopeClientException
                     && ((SyncopeClientException) e).getType() == ClientExceptionType.NotFound) {
                 LOG.info(e.getMessage());
             } else {
                 if (LOG.isDebugEnabled()) {
                     LOG.error("While fetching SAML2 IdP metadata", e);
                 } else {
                     LOG.error("While fetching SAML2 IdP metadata: " + e.getMessage());
                 }
             }
         }
 
         return null;
     }
 }