MarkdownSharp.Markdown.Normalize C# (CSharp) Method

        private string Normalize(string text)
        {            
            var output = new StringBuilder(text.Length);
            var line = new StringBuilder();
            bool valid = false;

            for (int i = 0; i < text.Length; i++)
            {
                switch (text[i])
                {
                    case '\n':
                        if (valid) output.Append(line);
                        output.Append('\n');
                        line.Length = 0; valid = false;
                        break;
                    case '\r':
                        if ((i < text.Length - 1) && (text[i + 1] != '\n'))
                        {
                            if (valid) output.Append(line);
                            output.Append('\n');
                            line.Length = 0; valid = false;
                        }
                        break;
                    case '\t':
                        int width = (_tabWidth - line.Length % _tabWidth);
                        for (int k = 0; k < width; k++)
                            line.Append(' ');
                        break;
                    case '\x1A':
                        break;
                    default:
                        if (!valid && text[i] != ' ') valid = true;
                        line.Append(text[i]);
                        break;
                }
            }

            if (valid) output.Append(line);
            output.Append('\n');

            // add two newlines to the end before return
            return output.Append("\n\n").ToString();
        }