/*
    * Licensed 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.gbif.ws.client;
  
  import java.text.ParseException;
  import java.text.SimpleDateFormat;
  import java.util.Date;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import feign.Param;
  
  /**
   * Convert date string from the default {@link Date} format to custom 'yyyy-MM'.
   */
  public class PartialDateExpander implements Param.Expander {
  
    private static final Logger LOG = LoggerFactory.getLogger(PartialDateExpander.class);
  
    private static final String UTIL_DATE_FORMAT_PATTERN = "EEE MMM dd HH:mm:ss zzz yyyy";
    private static final String CUSTOM_DATE_FORMAT_PATTERN = "yyyy-MM";
  
    @Override
    public String expand(Object value) {
      return convertDate(value);
    }
  
    private String convertDate(Object rawDate) {
      Date utilDate;
  
      try {
        utilDate = new SimpleDateFormat(UTIL_DATE_FORMAT_PATTERN).parse(rawDate.toString());
      } catch (ParseException e) {
        LOG.error("Wrong date format {}. Expected format: {}", rawDate, UTIL_DATE_FORMAT_PATTERN);
        return null;
      }
  
      return new SimpleDateFormat(CUSTOM_DATE_FORMAT_PATTERN).format(utilDate);
    }
  }