export function parseDateNoFallback()

in frontend/src/js/util/parseDate.js [55:109]
37 lines of code
16 McCabe index (conditional complexity)

export function parseDateNoFallback(text, mode) {
    // Date parser mode will chose either the from start of your date or the end
    // This is because if you say, "Give me all documents from after 2018" you don't want the
    // calculation to be from the first of January because you'd get results from all of 2018
    //
    // For example from_start '2018' returns 2018-01-01T00:00:00, from_end returns 2018-12-31T24:00:00
    if (mode !== 'from_start' && mode !== 'from_end') {
        throw new Error('Invalid date parsing mode');
    }


    let year, month, day;

    // Check if we can just parse the text text as a single year
    year = Number(text);
    if (!isNaN(year)) {
    // Check if we can just parse the text text as a single year
        if (mode === 'from_end') {
            year += 1;
        }

        return Date.UTC(year, 0);
    }

    const monthYear = monthYearDateRegex.exec(text);
    if (monthYear !== null && monthYear.length === 3 && validateMonth(monthYear[1]) && validateYear(monthYear[2])) {
        year = Number(monthYear[2]);
        month = getMonthIndex(monthYear[1]);

        if (mode === 'from_end') {
            month += 1;

            return Date.UTC(year, month);
        } else {
            return Date.UTC(year, month);
        }
    }

    const dayMonthYear = dayMonthYearDateRegex.exec(text);
    if (dayMonthYear !== null && dayMonthYear.length === 4 && validateDay(dayMonthYear[1]) && validateMonth(dayMonthYear[2]) && validateYear(dayMonthYear[3])) {
        year = Number(dayMonthYear[3]);
        month = getMonthIndex(dayMonthYear[2]);
        day = Number(dayMonthYear[1]);

        if (mode === 'from_end') {
            day += 1;

            return Date.UTC(year, month, day);
        } else {
            return Date.UTC(year, month, day);
        }
    }

    return null;
}