/*
    * This file is part of Waarp Project (named also Waarp or GG).
    *
    *  Copyright (c) 2019, Waarp SAS, and individual contributors by the @author
    *  tags. See the COPYRIGHT.txt in the distribution for a full listing of
    * individual contributors.
    *
    *  All Waarp Project is free software: you can redistribute it and/or
    * modify it under the terms of the GNU General Public License as published by
   * the Free Software Foundation, either version 3 of the License, or (at your
   * option) any later version.
   *
   * Waarp is distributed in the hope that it will be useful, but WITHOUT ANY
   * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
   * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License along with
   * Waarp . If not, see <http://www.gnu.org/licenses/>.
   */
  
  package org.waarp.openr66.protocol.http.restv2.resthandlers;
  
  import io.cdap.http.ExceptionHandler;
  import io.cdap.http.HttpResponder;
  import io.netty.handler.codec.http.DefaultHttpHeaders;
  import io.netty.handler.codec.http.HttpRequest;
  import org.waarp.common.logging.WaarpLogger;
  import org.waarp.common.logging.WaarpLoggerFactory;
  import org.waarp.openr66.protocol.http.restv2.errors.RestErrorException;
  import org.waarp.openr66.protocol.http.restv2.utils.JsonUtils;
  import org.waarp.openr66.protocol.http.restv2.utils.RestUtils;
  
  import javax.ws.rs.InternalServerErrorException;
  import javax.ws.rs.NotSupportedException;
  import java.util.Locale;
  
  import static io.netty.handler.codec.http.HttpResponseStatus.*;
  import static javax.ws.rs.core.HttpHeaders.*;
  
  /**
   * Handles all exceptions thrown by handlers during the processing of an HTTP
   * request.
   */
  public class RestExceptionHandler extends ExceptionHandler {
  
    /**
     * The logger for all events.
     */
    private static final WaarpLogger logger =
        WaarpLoggerFactory.getLogger(RestExceptionHandler.class);
  
    /**
     * Method called when an exception is thrown during the processing of a
     * request.
     *
     * @param t the exception thrown during execution
     * @param request the HttpRequest that failed
     * @param responder the HttpResponder for the request
     */
    @Override
    public void handle(final Throwable t, final HttpRequest request,
                       final HttpResponder responder) {
      if (t instanceof RestErrorException) {
        final RestErrorException userErrors = (RestErrorException) t;
        try {
          final Locale lang = RestUtils.getLocale(request);
          final String errorText =
              JsonUtils.nodeToString(userErrors.makeNode(lang));
          responder.sendJson(BAD_REQUEST, errorText);
        } catch (final InternalServerErrorException e) {
          logger.error(e);
          responder.sendStatus(INTERNAL_SERVER_ERROR);
        }
      } else if (t instanceof NotSupportedException) {
        final DefaultHttpHeaders headers = new DefaultHttpHeaders();
        headers.add(ACCEPT, t.getMessage());
        responder.sendStatus(UNSUPPORTED_MEDIA_TYPE, headers);
      } else {
        logger.error(t);
        responder.sendStatus(INTERNAL_SERVER_ERROR);
      }
    }
  }