TimeUtility is a utility class that provides a set of methods to handle time-related operations.

TimeUtility.ts

/**
 * TimeUtility is a utility class that provides a set of methods to handle time-related operations.
 *
 * @class     DatabaseManager
 * @author    Mohamed Riyad <m@ryad.me>
 * @link      https://RyadPasha.com
 * @copyright Copyright (C) 2023 RyadPasha. All rights reserved.
 * @license   MIT
 * @version   1.0.0-2023.07.26
 * @see       {@link https://momentjs.com/} for more information on Moment.js
 * @see       {@link https://gist.github.com/RyadPasha/ac3509aad9e4a1a91663777817c82e63} for updates
 */

import moment from 'moment-timezone'
import config from '../config/config'

class TimeUtility {
    /**
     * The default timezone to be used in case an invalid timezone is provided or no timezone is specified.
     */
    private readonly defaultTimezone: string

    /**
     * Create a TimeHandler instance.
     *
     * @param {string} timezone - Optional. The timezone to be used as the default timezone. If not provided or invalid, the default timezone will be GMT (UTC).
     */
    constructor(timezone?: string) {
        this.defaultTimezone = this.validateTimezone(timezone) || 'Etc/GMT'
    }

    /**
     * Get the current time in the default or specified timezone.
     *
     * @returns {moment.Moment} The current time as a Moment object.
     */
    getCurrentTime(): moment.Moment {
        return moment.tz(this.defaultTimezone)
    }

    /**
     * Format a given time according to a specified format string in the default or specified timezone.
     *
     * @param   {moment.Moment} time - The time to be formatted (a Moment object, a Date object, or a date string).
     * @param   {string} [formatString='YYYY-MM-DD HH:mm:ss'] - Optional. The format string to be used. Defaults to 'YYYY-MM-DD HH:mm:ss'.
     * @returns {string} The formatted time as a string.
     */
    formatTime(time: moment.Moment, formatString: string = 'YYYY-MM-DD HH:mm:ss'): string {
        return time.format(formatString)
    }

    /**
     * Convert a given time to the specified timezone.
     *
     * @param   {moment.Moment | Date | string} time - The time to be converted (a Moment object, a Date object, or a date string).
     * @param   {string} timezone - The timezone to which the time should be converted.
     * @returns {moment.Moment} The converted time as a Moment object.
     */
    convertToTimezone(time: moment.Moment | Date | string, timezone: string): moment.Moment {
        const tz = this.validateTimezone(timezone)
        return moment.tz(time, tz)
    }

    /**
     * Validate if the provided timezone is valid and exists in the moment-timezone database.
     * If the timezone is valid, it will be returned; otherwise, the default timezone will be used.
     *
     * @param   {string} timezone - The timezone to be validated.
     * @returns {string | null} The validated timezone or null if an invalid timezone was provided.
     */
    private validateTimezone(timezone?: string): string | null {
        if (timezone && moment.tz.names().includes(timezone)) {
            return timezone
        } else {
            console.warn('Invalid timezone provided. Fallback to GMT (UTC).')
            return null
        }
    }
}

const timeUtility = new TimeUtility(config.TIMEZONE)

export default timeUtility