// ==========================================================
// 	計時器功能
// ==========================================================
;(function($) {
    $('.timer').each(function(i, ele) {
    	const startTime = $(ele).data('start') * 1000
    	const endTime = $(ele).data('end') * 1000
    	
    	setInterval(countDown, 1000, ele, endTime, startTime)
    	countDown(ele, endTime, startTime)
    });


    function countDown(target, endTime, startTime) {
    	const nowTime = Date.now()

    	if(startTime > nowTime) {
    		$(target).text('尚未開始') 
    	} else if(nowTime > endTime) {
    		$(target).text('優惠結束')
    	} else {
	    	const leftTime = endTime - nowTime

    		const leftSec = Math.floor(leftTime / 1000) % 60
    		const leftMin = Math.floor(leftTime / 1000 / 60) % 60
    		const leftHour = Math.floor(leftTime / 1000 / 60 / 60) % 24

    		$(target).text(`${padLeft(leftHour, 2)}:${padLeft(leftMin, 2)}:${padLeft(leftSec, 2)}`)
    	}
    }

    function padLeft(content, length, symbol) {
    	let targetStr = content.toString()
    	let letter = symbol || 0

    	if(targetStr.length < length) {
			targetStr = letter + targetStr

			return padLeft(targetStr, length, letter)
    	} else {
    		return targetStr
    	}
    }
})($)