wdt = {
    last_wdt_time: 0,
    watchdog_counter: 0
}

pollFileChange = () => {
    setTimeout(() => {
        wdt.watchdog_counter++
        console.log(wdt.watchdog_counter)
        if (wdt.watchdog_counter > 20) {
            return
        }
        ajax({
            type: "GET",
            url: "/watchdog",
            success: (data) => {
                var time = Number(data)
                if (wdt.last_wdt_time == 0) {
                    wdt.last_wdt_time = time
                    pollFileChange()
                } else if (time > wdt.last_wdt_time) {
                    location.reload();
                } else {
                    pollFileChange()
                }
            },
        })
    }, 10000)
}

function ajax(setting) {
	if (typeof(shutdown) !== 'undefined') return
	var request = new XMLHttpRequest();
	request.open(setting.type, setting.url, true);
	request.setRequestHeader('Content-Type', setting.dataType)
	request.onload = function(data) {
		if (typeof(shutdown) !== 'undefined') return
		if (this.status >= 200 && this.status < 400) {
			if (setting.success) {
				setting.success(this.response)
			}
		} else {
			if (setting.error) {
				setting.error(this.response)
			}
		}
	}
	request.onerror = function(data) {
		if (typeof(shutdown) !== 'undefined') return
		if (setting.error) {
			setting.error(data)
		}
	}
	if (setting.data) {
		request.send(setting.data)
	} else {
		request.send()
	}
}



pollFileChange()