/// <summary>
        /// Method to handle inline replacement of style tag by closing style definition.
        /// </summary>
        /// <param name="charBuffer"></param>
        /// <param name="writeIndex"></param>
        /// <param name="styleStack"></param>
        /// <returns></returns>
        static void ReplaceClosingStyleTag(ref int[] charBuffer, ref int writeIndex, ref RichTextTagStack <int> styleStack)
        {
            // Get style from the Style Stack
            int       hashCode = styleStack.CurrentItem();
            TextStyle style    = TextStyleSheet.GetStyle(hashCode);

            styleStack.Remove();

            // Return if we don't have a valid style.
            if (style == null)
            {
                return;
            }

            int styleLength = style.styleClosingTagArray.Length;

            // Replace <style> tag with opening definition
            int[] closingTagArray = style.styleClosingTagArray;

            for (int i = 0; i < styleLength; i++)
            {
                int c = closingTagArray[i];

                if (c == 60)
                {
                    if (IsTagName(ref closingTagArray, "<BR>", i))
                    {
                        if (writeIndex == charBuffer.Length)
                        {
                            ResizeInternalArray(ref charBuffer);
                        }

                        charBuffer[writeIndex] = 10;
                        writeIndex            += 1;
                        i += 3;

                        continue;
                    }
                    if (IsTagName(ref closingTagArray, "<STYLE=", i))
                    {
                        int offset;
                        if (ReplaceOpeningStyleTag(ref closingTagArray, i, out offset, ref charBuffer, ref writeIndex, ref styleStack))
                        {
                            i = offset;
                            continue;
                        }
                    }
                    else if (IsTagName(ref closingTagArray, "</STYLE>", i))
                    {
                        ReplaceClosingStyleTag(ref charBuffer, ref writeIndex, ref styleStack);

                        // Strip </style> even if style is invalid.
                        i += 7;
                        continue;
                    }
                }

                if (writeIndex == charBuffer.Length)
                {
                    ResizeInternalArray(ref charBuffer);
                }

                charBuffer[writeIndex] = c;
                writeIndex            += 1;
            }
        }
 public static TextStyleSheet LoadDefaultStyleSheet()
 {
     TextStyleSheet.s_Instance = null;
     return(TextStyleSheet.instance);
 }
        /// <summary>
        /// Method to handle inline replacement of style tag by opening style definition.
        /// </summary>
        /// <param name="sourceText"></param>
        /// <param name="srcIndex"></param>
        /// <param name="srcOffset"></param>
        /// <param name="charBuffer"></param>
        /// <param name="writeIndex"></param>
        /// <param name="styleStack"></param>
        /// <returns></returns>
        static bool ReplaceOpeningStyleTag(ref string sourceText, int srcIndex, out int srcOffset, ref int[] charBuffer, ref int writeIndex, ref RichTextTagStack <int> styleStack)
        {
            // Validate <style> tag.
            int hashCode = GetTagHashCode(ref sourceText, srcIndex + 7, out srcOffset);

            TextStyle style = TextStyleSheet.GetStyle(hashCode);

            // Return if we don't have a valid style.
            if (style == null || srcOffset == 0)
            {
                return(false);
            }

            styleStack.Add(style.hashCode);

            int styleLength = style.styleOpeningTagArray.Length;

            // Replace <style> tag with opening definition
            int[] openingTagArray = style.styleOpeningTagArray;

            for (int i = 0; i < styleLength; i++)
            {
                int c = openingTagArray[i];

                if (c == 60)
                {
                    if (IsTagName(ref openingTagArray, "<BR>", i))
                    {
                        if (writeIndex == charBuffer.Length)
                        {
                            ResizeInternalArray(ref charBuffer);
                        }

                        charBuffer[writeIndex] = 10;
                        writeIndex            += 1;
                        i += 3;

                        continue;
                    }
                    if (IsTagName(ref openingTagArray, "<STYLE=", i))
                    {
                        int offset;
                        if (ReplaceOpeningStyleTag(ref openingTagArray, i, out offset, ref charBuffer, ref writeIndex, ref styleStack))
                        {
                            i = offset;
                            continue;
                        }
                    }
                    else if (IsTagName(ref openingTagArray, "</STYLE>", i))
                    {
                        ReplaceClosingStyleTag(ref charBuffer, ref writeIndex, ref styleStack);

                        // Strip </style> even if style is invalid.
                        i += 7;
                        continue;
                    }
                }

                if (writeIndex == charBuffer.Length)
                {
                    ResizeInternalArray(ref charBuffer);
                }

                charBuffer[writeIndex] = c;
                writeIndex            += 1;
            }

            return(true);
        }