export function dateToDatetimeLocal(date: Date): string {
    function ten(i: number) {
        return (i < 10 ? '0' : '') + i;
    }
    const YYYY = date.getFullYear();
    const MM = ten(date.getMonth() + 1);
    const DD = ten(date.getDate());
    const HH = ten(date.getHours());
    const II = ten(date.getMinutes());
    const SS = ten(date.getSeconds());
    return YYYY + '-' + MM + '-' + DD + 'T' +
        HH + ':' + II + ':' + SS;
}

export const dateToIsoString = (function (BST) {
    // BST should not be present as UTC time
    if (new Date(BST).toISOString().slice(0, 16) === BST) {
        return (date: Date): string => {
            return new Date(date.getTime() + date.getTimezoneOffset() * 60000)
                .toISOString();
        };
    } else {
        return (date: Date) => date.toISOString();
    }
}('2006-06-06T06:06'));