private void InputRichTextBox_OnSelectionChanged(object sender, RoutedEventArgs e)
{
if (MirrorToggleButton.IsChecked == false)
{
return;
}
OutputRichTextBox.ClearFormatting();
if (InputRichTextBox.Selection.IsEmpty || OutputRichTextBox.IsEmpty() || _containKeys)
{
return;
}
var inputStartPointer = InputRichTextBox.GetStart();
var outputStartPointer = OutputRichTextBox.GetStart();
var selectionStartPointer = InputRichTextBox.Selection.Start;
var selectedText = InputRichTextBox.Selection.Text;
var precedingText = new TextRange(inputStartPointer, selectionStartPointer).Text;
var encodedSelectedText = _selectedCipher.Encode(selectedText, CharsDelimiter, WordsDelimiter);
var encodedPrecedingText = _selectedCipher.Encode(precedingText, CharsDelimiter, WordsDelimiter);
var highlightStartPointer = outputStartPointer.GetPositionAtOffset(encodedPrecedingText.Length + 2);
var highlightEndPointer = highlightStartPointer?.GetPositionAtOffset(encodedSelectedText.Length + 2);
var highlightTextRange = new TextRange(highlightStartPointer, highlightEndPointer);
var brush = _isLight ? Brushes.Yellow : Brushes.DarkMagenta;
highlightTextRange.ApplyPropertyValue(TextElement.BackgroundProperty, brush);
}