javascript unix timestamp to date corrector[updated]

function converDate(dateToCheck) {
        var date = new Date(dateToCheck);
        var turningDate = new Date(1582, 9, 15);
        if (date.getTime() < turningDate.getTime()) {
            date.setDate(date.getDate() - 10);
        }
        var century = 1500
        while (date.getFullYear() < century) {
            if ((century % 400) != 0) {
                date.setDate(date.getDate() + 1);
            }
            century = century - 100;
        }
        var formatedTime = date.getFullYear() + '-' + (date.getMonth() + 1) + '-' + date.getDate();
        return formatedTime;
    }