Format Date.

DateFormat.js

class DateFormat {
  constructor(tmp) {
    this.tmp = +tmp || Date.now();
  }

  duration(format = 'HH:mm:ss') {
    let hour = ~~(this.tmp/1000/60/60);
    let minutes = ~~((this.tmp/1000/60)%60);
    let seconds = ~~((this.tmp/1000)%60);

    return format.replace(/HH|mm|ss/g, (reg) => {
      switch (reg) {
        case 'HH':
          return fill(hour);
          break;
        case 'mm':
          return fill(minutes);
          break;
        case 'ss':
          return fill(seconds);
          break;
      }
    });
  }

  format(format = 'YYYY-MM-DD HH:mm:ss') {
    const date = new Date(this.tmp);

    return format.replace(/YYYY|MM|DD|HH|mm|ss/g, (reg) => {
      switch (reg) {
        case 'YYYY':
          return fill(date.getFullYear());
          break;
        case 'MM':
          return fill(date.getMonth() + 1);
          break;
        case 'DD':
          return fill(date.getDate());
          break;
        case 'HH':
          return fill(date.getHours());
          break;
        case 'mm':
          return fill(date.getMinutes());
          break;
        case 'ss':
          return fill(date.getSeconds());
          break;
      }
    });
  }
}

const fill = (val) => val < 10 ? `0${val}` : val;

export default DateFormat;