ユニックスタイム unix time を年月日時分秒に変換

/**
 * unixtime to datetime
 *
 * author ao-system, Inc.
 * date 2024-08-09
 */
(() => {
	'use strict';
	new class {
		#unixTime = document.getElementById('unixtime');
		#offset = document.getElementById('offset');
		#result1 = document.getElementById('result1');
		#result2 = document.getElementById('result2');
		constructor() {
			const unixTime = Math.floor(Date.now() / 1000);
			this.#unixTime.value = unixTime;
			this.#calc();
			this.#unixTime.addEventListener('input', () => { this.#calc(); });
			this.#offset.addEventListener('input', () => { this.#calc(); });
		}
		#calc() {
			const date = new Date(this.#unixTime.value * 1000);
			const offset = this.#offset.value ? parseInt(this.#offset.value) : 0;
			date.setHours(date.getHours() + offset);
			const year		= date.getFullYear();
			const month		= ('0' + (date.getMonth() + 1)).slice(-2);
			const day		= ('0' + date.getDate()).slice(-2);
			const hour		= ('0' + date.getHours()).slice(-2);
			const minute	= ('0' + date.getMinutes()).slice(-2);
			const second	= ('0' + date.getSeconds()).slice(-2);
			this.#result1.value = `${year}-${month}-${day} ${hour}:${minute}:${second}`;
			this.#result2.value = `${year}年${month}月${day}日 ${hour}時${minute}分${second}秒`;
		}
	}
})();