BetterCMS.Module.LuceneSearch.Services.IndexerService.DefaultIndexerService.GetSnippet C# (CSharp) Method

        private static string GetSnippet(string text, string fullSearchString)
        {
            const int beforeStart = 100;
            const int afterEnd = 100;

            if (text.Length <= afterEnd + beforeStart)
            {
                return text;
            }

            var searchString = fullSearchString.Trim().Split(' ')[0].Trim('\'').Trim('"').Trim('*');

            // Find first position of the keyword
            int index;
            var pattern = string.Format("\\b{0}\\b", searchString);
            var match = Regex.Match(text, pattern, RegexOptions.IgnoreCase);
            if (match.Success)
            {
                index = match.Index;
            }
            else
            {
                index = text.IndexOf(searchString, StringComparison.InvariantCulture);
            }
            if (index < 0)
            {
                index = 0;
            }

            var textLength = text.Length;

            // Crop snippet from the whole search text
            var takeFromEnd = (index + afterEnd < textLength) ? 0 : afterEnd - (textLength - index);
            var startFrom = index - beforeStart - takeFromEnd;
            var addToEnd = 0;
            if (startFrom < 0)
            {
                startFrom = 0;
            }
            if (startFrom < beforeStart)
            {
                addToEnd = beforeStart - startFrom;
            }

            var endWith = index + afterEnd + addToEnd;
            if (endWith > textLength)
            {
                endWith = textLength;
            }

            if (startFrom > 0)
            {
                var spaceIndex = text.LastIndexOf(" ", startFrom, StringComparison.InvariantCulture);
                if (spaceIndex > 0)
                {
                    startFrom = spaceIndex;
                }
            }
            if (endWith < textLength)
            {
                var spaceIndex = text.IndexOf(" ", endWith, StringComparison.InvariantCulture);
                if (spaceIndex > 0)
                {
                    endWith = spaceIndex;
                }
            }

            var snippet = text.Substring(startFrom, endWith - startFrom);

            if (startFrom > 0)
            {
                snippet = string.Concat("...", snippet);
            }
            if (endWith < textLength)
            {
                snippet = string.Concat(snippet, "...");
            }

            return HttpUtility.HtmlDecode(snippet);
        }