/*
    * The MIT License (MIT)
    *
    * Copyright (c) 2013 - 2023, Tapio Rautonen
    *
    * Permission is hereby granted, free of charge, to any person obtaining a copy
    * of this software and associated documentation files (the "Software"), to deal
    * in the Software without restriction, including without limitation the rights
    * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  package org.eluder.coveralls.maven.plugin.util;
  
  import org.apache.commons.lang3.StringUtils;
  import org.eluder.coveralls.maven.plugin.ProcessingException;
  
  import java.text.DateFormat;
  import java.text.ParseException;
  import java.text.SimpleDateFormat;
  import java.util.Date;
  
  public class TimestampParser {
  
      public static final String EPOCH_MILLIS = "EpochMillis";
  
      public static final String DEFAULT_FORMAT = "yyyy-MM-dd'T'HH:mm:ss'Z'";
  
      private final Parser parser;
  
      public TimestampParser(final String format) {
          try {
              if (EPOCH_MILLIS.equalsIgnoreCase(format)) {
                  this.parser = new EpochMillisParser();
              } else if (StringUtils.isNotBlank(format)) {
                  this.parser = new DateFormatParser(format);
              } else {
                  this.parser = new DateFormatParser(DEFAULT_FORMAT);
              }
          } catch (IllegalArgumentException ex) {
              throw new IllegalArgumentException("Invalid timestamp format \"" + format + "\"", ex);
          }
      }
  
      public Date parse(final String timestamp) throws ProcessingException {
          if (StringUtils.isBlank(timestamp)) {
              return null;
          }
          try {
              return parser.parse(timestamp);
          } catch (Exception ex) {
              throw new ProcessingException("Unable to parse timestamp \"" + timestamp + "\"", ex);
          }
      }
  
      private interface Parser {
          Date parse(String timestamp) throws Exception;
      }
  
      private static class DateFormatParser implements Parser {
  
          final DateFormat format;
  
          DateFormatParser(final String format) {
              this.format = new SimpleDateFormat(format);
          }
  
          @Override
          public synchronized Date parse(final String timestamp) throws ParseException {
              return format.parse(timestamp);
          }
      }
  
      private static class EpochMillisParser implements Parser {
  
          @Override
          public Date parse(final String timestamp) {
              return new Date(Long.valueOf(timestamp));
          }
      }
  }