export const zero = (value: number | string) => value.toString().length === 1 ? `0${value}` : value;

export default class DateUtil{
    constructor() {
    }

    public static getCurrentDateTime(format?:string):string {
        return this.toDateString(new Date(), format);
    }

    public static toDateString(date:Date, format?:string):string{
        if (format == null || format == undefined) {
            format = "yyyy-MM-DD";
        }
        return this.toDateFormat(date, format);
    }

    public static toDateTimeString(date:Date, format?:string):string{
        if (format == null || format == undefined) {
            format = "yyyy-MM-DD H:i:s";
        }
        return this.toDateFormat(date, format);
    }

    public static toDateFormat(date: Date, format: string) {
        return format.replace(/(yyyy|mm|dd|MM|DD|H|i|s)/g, (t: string): any => {
            switch (t) {
                case "yyyy":
                    return date.getFullYear();
                case "mm":
                    return date.getMonth() + 1;
                case "dd":
                    return date.getDate();
                case "MM":
                    return zero(date.getMonth() + 1);
                case "DD":
                    return zero(date.getDate());
                case "H":
                    return zero(date.getHours());
                case "i":
                    return zero(date.getMinutes());
                case "s":
                    return zero(date.getSeconds());
                default:
                    return "";
            }
        });

    }

    public static addMonth(date:Date, gap:number):Date{
        let yy1:number = date.getFullYear();
        let mm1:number = date.getMonth();
        let dd1:number = date.getDate();
        return new Date(yy1, mm1+gap, dd1);
    }

    public static addDay(date:Date, gap:number):Date{
        let yy1:number = date.getFullYear();
        let mm1:number = date.getMonth();
        let dd1:number = date.getDate();
        return new Date(yy1, mm1, dd1+gap);
    }
}