/*
    * Copyright (c) 2002-2025, City of Paris
    * All rights reserved.
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions
    * are met:
    *
    *  1. Redistributions of source code must retain the above copyright notice
   *     and the following disclaimer.
   *
   *  2. Redistributions in binary form must reproduce the above copyright notice
   *     and the following disclaimer in the documentation and/or other materials
   *     provided with the distribution.
   *
   *  3. Neither the name of 'Mairie de Paris' nor 'Lutece' nor the names of its
   *     contributors may be used to endorse or promote products derived from
   *     this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   * License 1.0
   */
  package fr.paris.lutece.plugins.oauth2.business;
  
  import java.io.IOException;
  import java.util.Objects;
  import java.util.Set;
  
  import com.fasterxml.jackson.databind.DeserializationFeature;
  import com.fasterxml.jackson.databind.ObjectMapper;
  
  import fr.paris.lutece.plugins.oauth2.service.CachingHttpAccessService;
  import fr.paris.lutece.portal.service.util.AppException;
  import fr.paris.lutece.util.httpaccess.HttpAccess;
  import fr.paris.lutece.util.httpaccess.HttpAccessException;
  import fr.paris.lutece.util.httpaccess.HttpAccessService;
  import fr.paris.lutece.util.httpaccess.PropertiesHttpClientConfiguration;
  
  /**
   * Server configuration for OpenID Connect
   * 
   * @since 2.0.0
   */
  public class OIDCAuthServerConf extends AuthServerConf
  {
      private static final long serialVersionUID = 3459341547945895738L;
      private static final String WELLKNOWN_PATH = ".well-known/openid-configuration";
  
      private final HttpAccess _httpAccess;
      private final ObjectMapper _mapper;
  
      public OIDCAuthServerConf( )
      {
          HttpAccessService accessService = new CachingHttpAccessService( new PropertiesHttpClientConfiguration( ) );
          this._httpAccess = new HttpAccess( accessService );
          this._mapper = new ObjectMapper( );
          this._mapper.configure( DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false );
      }
  
      @Override
      public boolean isEnableJwtParser( )
      {
          return true;
      }
  
      @Override
      public String getAuthorizationEndpointUri( )
      {
          if ( super.getAuthorizationEndpointUri( ) != null )
          {
              return super.getAuthorizationEndpointUri( );
          }
          return getOpenidConfiguration( ).getAuthorizationEndpoint( );
      }
  
      @Override
      public String getTokenEndpointUri( )
      {
          if ( super.getTokenEndpointUri( ) != null )
          {
              return super.getTokenEndpointUri( );
          }
          return getOpenidConfiguration( ).getTokenEndpoint( );
      }
  
      @Override
      public Set<String> getIDTokenSignatureAlgorithmNames( )
      {
         if ( super.getIDTokenSignatureAlgorithmNames( ) != null )
         {
             return super.getIDTokenSignatureAlgorithmNames( );
         }
         return Set.of( getOpenidConfiguration( ).getIDTokenSigningAlgValuesSupported( ) );
     }
 
     @Override
     public String getJwksEndpointUri( )
     {
         if ( super.getJwksEndpointUri( ) != null )
         {
             return super.getJwksEndpointUri( );
         }
         return getOpenidConfiguration( ).getJwksURI( );
     }
 
     @Override
     public String getLogoutEndpointUri( )
     {
         if ( super.getLogoutEndpointUri( ) != null )
         {
             return super.getLogoutEndpointUri( );
         }
         return getOpenidConfiguration( ).getEndSessionEndpoint( );
     }
 
     private OpenIDConfiguration getOpenidConfiguration( )
     {
         String issuer = getIssuer( );
         Objects.requireNonNull( issuer, "issuer must not be null" );
         if ( !issuer.startsWith( "https" ) )
         {
             throw new UnsupportedOperationException( "The issuer must start with https, but is " + issuer );
         }
         String strConfURL;
         if ( issuer.endsWith( "/" ) )
         {
             strConfURL = issuer + WELLKNOWN_PATH;
         }
         else
         {
             strConfURL = issuer + "/" + WELLKNOWN_PATH;
         }
         try
         {
             String strConfiguration = _httpAccess.doGet( strConfURL );
             OpenIDConfiguration res = this._mapper.readValue( strConfiguration, OpenIDConfiguration.class );
             res.validate( issuer );
             return res;
         }
         catch( HttpAccessException | IOException e )
         {
             throw new AppException( e.getMessage( ), e );
         }
     }
 }