package org.openjdk;

import org.openjdk.jmh.annotations.*; 
import java.util.*;
import java.util.concurrent.*;
import java.time.*;

@State(Scope.Benchmark)
public class ZipUtilsMixed {

    @Param("677456332112")
    public long dosTime;

    @Param("0")
    public long dosTime2;

    @Setup
    public void setup() {
        long dtime = dosTime;
        int year = (int) (((dtime >> 25) & 0x7f) + 1980);
        int month = (int) ((dtime >> 21) & 0x0f);
        int day = (int) ((dtime >> 16) & 0x1f);
        int hour = (int) ((dtime >> 11) & 0x1f);
        int minute = (int) ((dtime >> 5) & 0x3f);
        int second = (int) ((dtime << 1) & 0x3e);
        System.out.println(year + "-" + month + "-" + day + " " + hour + ":" + minute + ":" + second);    
    }

    @Benchmark
    public long dosToJavaTime8Bench() {
        return dosToJavaTime8(dosTime) + dosToJavaTime8(dosTime2);
    }

    public static long dosToJavaTime8(long dtime) {
        Date d = new Date((int)(((dtime >> 25) & 0x7f) + 80),
                          (int)(((dtime >> 21) & 0x0f) - 1),
                          (int)((dtime >> 16) & 0x1f),
                          (int)((dtime >> 11) & 0x1f),
                          (int)((dtime >> 5) & 0x3f),
                          (int)((dtime << 1) & 0x3e));
        return d.getTime();
    }

    @Benchmark
    public long dosToJavaTime9Bench() {
        return dosToJavaTime9(dosTime) + dosToJavaTime9(dosTime);
    }

    public static long dosToJavaTime9(long dtime) {
        int year = (int) (((dtime >> 25) & 0x7f) + 1980);
        int month = (int) ((dtime >> 21) & 0x0f);
        int day = (int) ((dtime >> 16) & 0x1f);
        int hour = (int) ((dtime >> 11) & 0x1f);
        int minute = (int) ((dtime >> 5) & 0x3f);
        int second = (int) ((dtime << 1) & 0x3e);

        try {
            LocalDateTime ldt = LocalDateTime.of(year, month, day, hour, minute, second);
            return TimeUnit.MILLISECONDS.convert(ldt.toEpochSecond(
                ZoneId.systemDefault().getRules().getOffset(ldt)), TimeUnit.SECONDS);
        } catch (DateTimeException dte) {
            return overflowDosToJavaTime(year, month, day, hour, minute, second);
        }
    }

    @SuppressWarnings("deprecation") // Use of date constructor
    private static long overflowDosToJavaTime(int year, int month, int day, int hour, int minute, int second) {
        return new Date(year - 1900, month - 1, day, hour, minute, second).getTime();
    }

    @Benchmark
    public long dosToJavaTime9Bench2() {
        return dosToJavaTime92(dosTime) + dosToJavaTime92(dosTime2);
    }

    public static long dosToJavaTime92(long dtime) {
        int year = (int) (((dtime >> 25) & 0x7f) + 1980);
        int month = (int) ((dtime >> 21) & 0x0f);
        int day = (int) ((dtime >> 16) & 0x1f);
        int hour = (int) ((dtime >> 11) & 0x1f);
        int minute = (int) ((dtime >> 5) & 0x3f);
        int second = (int) ((dtime << 1) & 0x3e);

        if (month >= 1 && day >= 0 && second < 60 && minute < 60 && hour < 24) {
          try {
              LocalDateTime ldt = LocalDateTime.of(year, month, day, hour, minute, second);
              return TimeUnit.MILLISECONDS.convert(ldt.toEpochSecond(
                  ZoneId.systemDefault().getRules().getOffset(ldt)), TimeUnit.SECONDS);
          } catch (DateTimeException dte) {
              // ignore
          }
        }
        return overflowDosToJavaTime(year, month, day, hour, minute, second);
    }

    public ZipUtilsMixed() {
    }
}