private static DateTime? TryParseDateTimeUtcFromString()

in src/Utilities.cs [359:399]
31 lines of code
8 McCabe index (conditional complexity)

        private static DateTime? TryParseDateTimeUtcFromString(string sourceString, DateTimeFormatPattern dateTimeFormat)
        {
            if (dateTimeFormat == null || string.IsNullOrWhiteSpace(sourceString))
            {
                return null;
            }

            if (sourceString.Length < dateTimeFormat.Prefix.Length + dateTimeFormat.Format.Length + dateTimeFormat.Suffix.Length)
            {
                return null;
            }

            int startIndex = 0;
            while ((startIndex = sourceString.IndexOf(dateTimeFormat.Prefix, startIndex)) >= 0)
            {
                // Advance post prefix
                startIndex += dateTimeFormat.Prefix.Length;

                // Look for suffix, skipping the DateTime format part
                int suffixStartIndex = sourceString.IndexOf(dateTimeFormat.Suffix, startIndex + dateTimeFormat.Format.Length);

                if (suffixStartIndex < 0)
                {
                    // If the suffix cannot be found - we are done searchng for it
                    break;
                }

                if (suffixStartIndex - startIndex >= dateTimeFormat.Format.Length)
                {
                    var dateTimePortion = sourceString.Substring(startIndex, suffixStartIndex - startIndex);

                    DateTime ret;
                    if (ExtendedDateTime.TryParseExactUtc(dateTimePortion, dateTimeFormat.Format, out ret))
                    {
                        return ret;
                    }
                }
            }

            return null;
        }