/*
    * Licensed to The Apereo Foundation under one or more contributor license
    * agreements. See the NOTICE file distributed with this work for additional
    * information regarding copyright ownership.
    *
    *
    * The Apereo Foundation licenses this file to you under the Educational
    * Community 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://opensource.org/licenses/ecl2.txt
   *
   * 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.opencastproject.userdirectory.ldap;
  
  import org.springframework.ldap.core.DirContextAdapter;
  import org.springframework.ldap.core.DirContextOperations;
  import org.springframework.security.core.GrantedAuthority;
  import org.springframework.security.core.userdetails.UserDetails;
  import org.springframework.security.ldap.userdetails.UserDetailsContextMapper;
  
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.List;
  import java.util.Objects;
  import java.util.StringJoiner;
  
  public class OpencastUserDetailsContextMapper implements UserDetailsContextMapper {
  
    private final String[] name;
  
    private final String mail;
  
    public OpencastUserDetailsContextMapper(String[] name, String mail) {
      Objects.requireNonNull(name);
      Objects.requireNonNull(mail);
      this.name = name;
      this.mail = mail;
    }
  
    @Override
    public UserDetails mapUserFromContext(DirContextOperations ctx, String username,
        Collection<? extends GrantedAuthority> authorities) {
      String dn = ctx.getNameInNamespace();
  
      OpencastUserDetails.Essence essence = new OpencastUserDetails.Essence();
      essence.setDn(dn);
      essence.setUsername(username);
      essence.setName(buildName(ctx));
      essence.setMail(ctx.getStringAttribute(mail));
  
      // Add the supplied authorities
      for (GrantedAuthority authority : authorities) {
        essence.addAuthority(authority);
      }
  
      return essence.createUserDetails();
    }
    private String buildName(DirContextOperations ctx) {
      StringJoiner joiner = new StringJoiner(" ");
      for (String attribute: name) {
        joiner.add(ctx.getStringAttribute(attribute));
      }
      return joiner.toString();
    }
  
    @Override
    public void mapUserToContext(UserDetails user, DirContextAdapter ctx) {
      throw new UnsupportedOperationException("OpencastUserContextMapper only supports reading from a context. Please"
          + "use a subclass if mapUserToContext() is required.");
    }
  
    public String[] getAttributes() {
      List<String> attributes = new ArrayList<>(Arrays.asList(name));
      attributes.add(mail);
      return attributes.toArray(new String[] {});
    }
  }