/*
    * Copyright 2021 TiKV Project Authors.
    *
    * 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.tikv.common.columnar;
  
  /**
   * TiCoreTime is TiDB's representation of date/datetime/timestamp, used to decode chunk data from
   * dag response
   */
  public class TiCoreTime {
    // copied from https://github.com/pingcap/tidb/blob/master/types/time.go
    private static final long YEAR_BIT_FIELD_OFFSET = 50, YEAR_BIT_FIELD_WIDTH = 14;
    private static final long MONTH_BIT_FIELD_OFFSET = 46, MONTH_BIT_FIELD_WIDTH = 4;
    private static final long DAY_BIT_FIELD_OFFSET = 41, DAY_BIT_FIELD_WIDTH = 5;
    private static final long HOUR_BIT_FIELD_OFFSET = 36, HOUR_BIT_FIELD_WIDTH = 5;
    private static final long MINUTE_BIT_FIELD_OFFSET = 30, MINUTE_BIT_FIELD_WIDTH = 6;
    private static final long SECOND_BIT_FIELD_OFFSET = 24, SECOND_BIT_FIELD_WIDTH = 6;
    private static final long MICROSECOND_BIT_FIELD_OFFSET = 4, MICROSECOND_BIT_FIELD_WIDTH = 20;
    private static final long YEAR_BIT_FIELD_MASK =
        ((1L << YEAR_BIT_FIELD_WIDTH) - 1) << YEAR_BIT_FIELD_OFFSET;
    private static final long MONTH_BIT_FIELD_MASK =
        ((1L << MONTH_BIT_FIELD_WIDTH) - 1) << MONTH_BIT_FIELD_OFFSET;
    private static final long DAY_BIT_FIELD_MASK =
        ((1L << DAY_BIT_FIELD_WIDTH) - 1) << DAY_BIT_FIELD_OFFSET;
    private static final long HOUR_BIT_FIELD_MASK =
        ((1L << HOUR_BIT_FIELD_WIDTH) - 1) << HOUR_BIT_FIELD_OFFSET;
    private static final long MINUTE_BIT_FIELD_MASK =
        ((1L << MINUTE_BIT_FIELD_WIDTH) - 1) << MINUTE_BIT_FIELD_OFFSET;
    private static final long SECOND_BIT_FIELD_MASK =
        ((1L << SECOND_BIT_FIELD_WIDTH) - 1) << SECOND_BIT_FIELD_OFFSET;
    private static final long MICROSECOND_BIT_FIELD_MASK =
        ((1L << MICROSECOND_BIT_FIELD_WIDTH) - 1) << MICROSECOND_BIT_FIELD_OFFSET;
  
    private final long coreTime;
  
    public TiCoreTime(long coreTime) {
      this.coreTime = coreTime;
    }
  
    public int getYear() {
      return (int) ((coreTime & YEAR_BIT_FIELD_MASK) >>> YEAR_BIT_FIELD_OFFSET);
    }
  
    public int getMonth() {
      return (int) ((coreTime & MONTH_BIT_FIELD_MASK) >>> MONTH_BIT_FIELD_OFFSET);
    }
  
    public int getDay() {
      return (int) ((coreTime & DAY_BIT_FIELD_MASK) >>> DAY_BIT_FIELD_OFFSET);
    }
  
    public int getHour() {
      return (int) ((coreTime & HOUR_BIT_FIELD_MASK) >>> HOUR_BIT_FIELD_OFFSET);
    }
  
    public int getMinute() {
      return (int) ((coreTime & MINUTE_BIT_FIELD_MASK) >>> MINUTE_BIT_FIELD_OFFSET);
    }
  
    public int getSecond() {
      return (int) ((coreTime & SECOND_BIT_FIELD_MASK) >>> SECOND_BIT_FIELD_OFFSET);
    }
  
    public long getMicroSecond() {
      return (coreTime & MICROSECOND_BIT_FIELD_MASK) >>> MICROSECOND_BIT_FIELD_OFFSET;
    }
  }