/*
    * Copyright (c) 2002-2023, 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.knowledge.rs;
  import fr.paris.lutece.util.json.ErrorJsonResponse;
  import fr.paris.lutece.portal.service.security.SecurityService;
  import javax.ws.rs.GET;
  import javax.ws.rs.POST;
  import javax.ws.rs.Path;
  import javax.ws.rs.Produces;
  import javax.ws.rs.core.MediaType;
  import javax.ws.rs.core.Response;
  import fr.paris.lutece.plugins.knowledge.service.ChatService;
  import org.glassfish.jersey.media.sse.EventOutput;
  import org.glassfish.jersey.media.sse.OutboundEvent;
  import org.glassfish.jersey.media.sse.SseFeature;
  
  import java.io.IOException;
  import java.util.UUID;
  import java.util.concurrent.CompletableFuture;
  import java.util.concurrent.ConcurrentHashMap;
  import javax.servlet.http.HttpServletRequest;
  import javax.ws.rs.Consumes;
  import javax.ws.rs.QueryParam;
  import javax.ws.rs.core.Context;
  
  /**
   * ProjectRest
   */
  @Path( Constants.API_PATH + Constants.VERSION_PATH + Constants.BOT_PATH )
  public class BotRest
  {
      private static ConcurrentHashMap<String, EventOutput> sessions = new ConcurrentHashMap<>( );
  
      @POST
      @Path( "/chat" )
      @Consumes( MediaType.APPLICATION_JSON )
      @Produces( MediaType.APPLICATION_JSON )
      public Response postChat( RequestData data, @Context HttpServletRequest request )
      {
          if ( SecurityService.getInstance( ).getRegisteredUser( request ) == null )
          {
              return Response.status( Response.Status.UNAUTHORIZED ).entity( new ErrorJsonResponse( "Unauthorized" ) ).build( );
          }
  
          String sessionId = UUID.randomUUID( ).toString( );
          final EventOutput eventOutput = new EventOutput( );
          sessions.put( sessionId, eventOutput );
          CompletableFuture<Void> future = ChatService.run( request, data, eventOutput, sessionId );
          future.whenComplete( ( result, ex ) -> {
              try
              {
  
                  OutboundEvent closeEvent = new OutboundEvent.Builder( ).name( "message" ).mediaType( MediaType.APPLICATION_JSON_TYPE )
                          .data( String.class, "CLOSE" ).build( );
                  eventOutput.write( closeEvent );
                  eventOutput.close( );
  
              }
              catch( IOException ioClose )
              {
                  throw new RuntimeException( "Error when closing the event output.", ioClose );
              }
          } );
  
          return Response.ok( ).entity( "{\"sessionId\":\"" + sessionId + "\"}" ).build( );
      }
  
     @GET
     @Path( "/chat/sse" )
     @Produces( SseFeature.SERVER_SENT_EVENTS )
     public EventOutput getChatEvents( @QueryParam( "sessionId" ) String sessionId, @Context HttpServletRequest request )
     {
         if ( SecurityService.getInstance( ).getRegisteredUser( request ) == null )
         {
             return null;
         }
         return sessions.get( sessionId );
     }
 
 }