/*
 * 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.knox.gateway.ha.dispatch;

import org.apache.http.Header;
import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpUriRequest;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

public class AtlasTrustedProxyHaDispatch extends ConfigurableHADispatch {
  public AtlasTrustedProxyHaDispatch() {
    setServiceRole("ATLAS");
  }

  @Override
  protected void executeRequest(HttpUriRequest outboundRequest,
                                HttpServletRequest inboundRequest,
                                HttpServletResponse outboundResponse) throws IOException {
    HttpResponse inboundResponse = null;
    try {
      inboundResponse = executeOutboundRequest(outboundRequest);

      int sc = inboundResponse.getStatusLine().getStatusCode();
      if (sc == HttpServletResponse.SC_MOVED_TEMPORARILY || sc == HttpServletResponse.SC_TEMPORARY_REDIRECT) {
        if (!isLoginRedirect(inboundResponse.getFirstHeader("Location"))) {
          inboundResponse.removeHeaders("Location");
          failoverRequest(outboundRequest,
              inboundRequest,
              outboundResponse,
              inboundResponse,
              new Exception("Atlas HA redirection"));
        }
      }

      writeOutboundResponse(outboundRequest, inboundRequest, outboundResponse, inboundResponse);

    } catch (IOException e) {
      LOG.errorConnectingToServer(outboundRequest.getURI().toString(), e);
      failoverRequest(outboundRequest, inboundRequest, outboundResponse, inboundResponse, e);
    }
  }

  private boolean isLoginRedirect(Header locationHeader) {
    boolean result = false;
    if (locationHeader != null) {
      String value = locationHeader.getValue();
      result = (value.endsWith("login.jsp") || value.contains("originalUrl"));
    }
    return result;
  }
}
