content: /*
   * 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.calcite.util.format.postgresql.format.compiled;
  
  import org.apache.calcite.util.format.postgresql.ChronoUnitEnum;
  import org.apache.calcite.util.format.postgresql.PatternModifier;
  
  import java.text.ParseException;
  import java.text.ParsePosition;
  import java.time.ZonedDateTime;
  import java.util.Locale;
  import java.util.Set;
  
  import static java.lang.Integer.parseInt;
  
  /**
   * The date/time format compiled component for the hours of the timezone offset.
   */
  public class TimeZoneHoursCompiledPattern extends CompiledPattern {
    public TimeZoneHoursCompiledPattern(Set<PatternModifier> modifiers) {
      super(ChronoUnitEnum.TIMEZONE_HOURS, modifiers);
    }
  
    @Override public String convertToString(ZonedDateTime dateTime, Locale locale) {
      return String.format(
          Locale.ROOT,
          "%+02d",
          dateTime.getOffset().getTotalSeconds() / 3600);
    }
  
    @Override public int parseValue(ParsePosition inputPosition, String input, boolean enforceLength,
        Locale locale) throws ParseException {
      int inputOffset = inputPosition.getIndex();
      String inputTrimmed = input.substring(inputOffset);
  
      boolean isPositive = true;
      if (inputTrimmed.charAt(0) == '-') {
        isPositive = false;
      } else if (inputTrimmed.charAt(0) != '+') {
        throw new ParseException("Unable to parse value", inputPosition.getIndex());
      }
  
      inputOffset++;
      inputTrimmed = input.substring(inputOffset);
  
      if (!Character.isDigit(inputTrimmed.charAt(0))) {
        throw new ParseException("Unable to parse value", inputPosition.getIndex());
      }
  
      int endIndex = inputOffset + 1;
      if (endIndex > input.length() || !Character.isDigit(input.charAt(inputOffset))) {
        throw new ParseException("Unable to parse value", inputPosition.getIndex());
      }
  
      if (endIndex < input.length() && Character.isDigit(input.charAt(endIndex))) {
        endIndex++;
      }
  
      int timezoneHours = parseInt(input.substring(inputOffset, endIndex));
  
      if (timezoneHours > 15) {
        throw new ParseException("Value is outside of valid range", inputPosition.getIndex());
      }
  
      inputPosition.setIndex(endIndex);
      return isPositive ? timezoneHours : -1 * timezoneHours;
    }
  
    @Override protected int getBaseFormatPatternLength() {
      return 3;
    }
  
    @Override public boolean isNumeric() {
      return true;
    }
  }
  