/**
 * 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.metron.rest.controller;

import org.apache.commons.lang3.exception.ExceptionUtils;
import org.apache.metron.rest.RestException;
import org.apache.metron.rest.model.RestError;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;

import javax.servlet.http.HttpServletRequest;
import java.lang.invoke.MethodHandles;

@ControllerAdvice(basePackages = "org.apache.metron.rest.controller")
public class RestExceptionHandler extends ResponseEntityExceptionHandler {
  private static final Logger LOG = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());

  @ExceptionHandler(RestException.class)
  @ResponseBody
  ResponseEntity<?> handleControllerException(HttpServletRequest request, Throwable ex) {
    HttpStatus status = getStatus(request);
    LOG.error("Encountered error: " + ex.getMessage(), ex);
    return new ResponseEntity<>(new RestError(status.value(), ex.getMessage(), ExceptionUtils.getRootCauseMessage(ex)), status);
  }

  private HttpStatus getStatus(HttpServletRequest request) {
    Integer statusCode = (Integer) request.getAttribute("javax.servlet.error.status_code");
    if (statusCode == null) {
      return HttpStatus.INTERNAL_SERVER_ERROR;
    }
    return HttpStatus.valueOf(statusCode);
  }
}
