var parseDateTimeMaybeOffset = function()

in JSLib/src/odata-utils.js [771:853]
60 lines of code
16 McCabe index (conditional complexity)

    var parseDateTimeMaybeOffset = function (value, withOffset, nullOnError) {
        /// <summary>Parses a string into a DateTime value.</summary>
        /// <param name="value" type="String">Value to parse.</param>
        /// <param name="withOffset" type="Boolean">Whether offset is expected.</param>
        /// <returns type="Date">The parsed value.</returns>

        // We cannot parse this in cases of failure to match or if offset information is specified.
        var parts = parseDateTimeRE.exec(value);
        var offset = (parts) ? getCanonicalTimezone(parts[8]) : null;

        if (!parts || (!withOffset && offset !== "Z")) {
            if (nullOnError) {
                return null;
            }
            throw { message: "Invalid date/time value" };
        }

        // Pre-parse years, account for year '0' being invalid in dateTime.
        var year = parseInt10(parts[1]);
        if (year <= 0) {
            year++;
        }

        // Pre-parse optional milliseconds, fill in default. Fail if value is too precise.
        var ms = parts[7];
        var ns = 0;
        if (!ms) {
            ms = 0;
        } else {
            if (ms.length > 7) {
                if (nullOnError) {
                    return null;
                }
                throw { message: "Cannot parse date/time value to given precision." };
            }

            ns = formatNumberWidth(ms.substring(3), 4, true);
            ms = formatNumberWidth(ms.substring(0, 3), 3, true);

            ms = parseInt10(ms);
            ns = parseInt10(ns);
        }

        // Pre-parse other time components and offset them if necessary.
        var hours = parseInt10(parts[4]);
        var minutes = parseInt10(parts[5]);
        var seconds = parseInt10(parts[6]) || 0;
        if (offset !== "Z") {
            // The offset is reversed to get back the UTC date, which is
            // what the API will eventually have.
            var timezone = parseTimezone(offset);
            var direction = -(timezone.d);
            hours += timezone.h * direction;
            minutes += timezone.m * direction;
        }

        // Set the date and time separately with setFullYear, so years 0-99 aren't biased like in Date.UTC.
        var result = new Date();
        result.setUTCFullYear(
            year,                       // Year.
            parseInt10(parts[2]) - 1,   // Month (zero-based for Date.UTC and setFullYear).
            parseInt10(parts[3])        // Date.
            );
        result.setUTCHours(hours, minutes, seconds, ms);

        if (isNaN(result.valueOf())) {
            if (nullOnError) {
                return null;
            }
            throw { message: "Invalid date/time value" };
        }

        if (withOffset) {
            result.__edmType = "Edm.DateTimeOffset";
            result.__offset = offset;
        }

        if (ns) {
            result.__ns = ns;
        }

        return result;
    };