Timestamp.ts

import moment from 'moment'

class Timestamp {
    private timestamp: string;
    private readonly format = 'YYY-MM-DD HH:mm:ss'

    private constructor(timestamp: string) {
        this.timestamp = timestamp
    }

    private isValid(timestamp: string): Boolean {
        return moment(timestamp, this.format, true).isValid()
    }

    public toString(): string {
        return moment(this.timestamp).format(this.format)
    }

    public fromString(timestamp: string): Timestamp {
        if (timestamp === '' && !this.isValid(timestamp)) {
            throw Error('Invalid timestamp')
        }
        return new Timestamp(moment(timestamp).format(this.format))
    }

    public equals(that: Timestamp): Boolean {
        return that.timestamp === this.timestamp
    }

    public isBefore(that: Timestamp): Boolean {
        return moment(this.timestamp).isBefore(that.timestamp)
    }

    public isAfter(that: Timestamp): Boolean {
        return moment(this.timestamp).isAfter(that.timestamp)
    }
}