New Post: Problems with colspan and rowspan together

Had a similar problem with a parent row containing both a horizontally merged cell and a vertically merged cell.
The following code need to be reviewed and better rewritten, but it works for now.

        private void ProcessClosingTableRow(HtmlEnumerator en)
        {
            if (!tables.HasContext) return;
            TableRow row = tables.CurrentTable.GetLastChild<TableRow>();
            if (row == null) return;

            // Word will not open documents with empty rows (reported by scwebgroup)
            if (row.GetFirstChild<TableCell>() == null)
            {
                row.Remove();
                return;
            }

            // Add empty columns to fill rowspan
            if (tables.RowSpan.Count > 0)
            {
                int rowIndex = tables.CellPosition.Y;

                for (int i = 0; i < tables.RowSpan.Count; i++)
                {
                    Point position = tables.RowSpan.Keys[i];
                    if (position.Y == rowIndex) continue;

                    //note: incorrect when the row source of the rowspan contains some horizontally spanned cells), position.X can be invalid
                    //row.InsertAt<TableCell>(new TableCell(new TableCellProperties(
                    //                            new VerticalMerge()),
                    //                        new Paragraph()),
                    //    position.X);

                    TableRow spanSourceRow = tables.CurrentTable.ChildElements.OfType<TableRow>().ElementAtOrDefault(position.Y - 1);
                    int insertPos = position.X;
                    int gridspan = 0;
                    if (spanSourceRow != null)
                    {
                        int virtualInsertPos = spanSourceRow.ChildElements.OfType<TableCell>().Take(position.X + 1)
                                                 .Sum(c =>
                                                        {
                                                            if (c.TableCellProperties != null && c.TableCellProperties.GridSpan != null && c.TableCellProperties.VerticalMerge == null)
                                                                return (int) c.TableCellProperties.GridSpan.Val;
                                                            return 1;
                                                        }) - 1;
                        // the destination row can have horizontally merged cells too
                        int hiddenColumnsCountBeforeInsertPos = 0;
                        if (virtualInsertPos > 0)
                        {
                            int virtualDestInsertPos = 0;
                            foreach (var c in row.ChildElements.OfType<TableCell>())
                            {
                                if (c.TableCellProperties != null && c.TableCellProperties.GridSpan != null)
                                {
                                    hiddenColumnsCountBeforeInsertPos += (int) c.TableCellProperties.GridSpan.Val - 1;
                                    virtualDestInsertPos += (int) c.TableCellProperties.GridSpan.Val;
                                }
                                else
                                    virtualDestInsertPos++;
                                if (virtualDestInsertPos >= virtualInsertPos)
                                    break;
                            }
                        }
                        insertPos = virtualInsertPos - hiddenColumnsCountBeforeInsertPos;

                        //report gridspan from the parent cell 
                        var parentCell = spanSourceRow.ChildElements.OfType<TableCell>().Skip(position.X).FirstOrDefault();
                        if (parentCell != null && parentCell.TableCellProperties != null && parentCell.TableCellProperties.GridSpan != null)
                            gridspan = parentCell.TableCellProperties.GridSpan.Val;
                    }

                    var tcProps = new TableCellProperties();
                    if (gridspan > 0)
                        tcProps.AppendChild(new GridSpan() {Val = gridspan});
                    row.InsertAt<TableCell>(new TableCell(tcProps, new Paragraph()), insertPos);

                    int span = tables.RowSpan[position];
                    if (span == 1) { tables.RowSpan.RemoveAt(i); i--; }
                    else tables.RowSpan[position] = span - 1;
                }
            }

            htmlStyles.Tables.EndTag("<tr>");
            htmlStyles.Runs.EndTag("<tr>");
        }