private static void indentPlainTextBlock(final @NotNull Document document, final int startOffset, final int endOffset, final int indentLevel) {
    CharSequence chars = document.getCharsSequence();
    int spaceEnd = CharArrayUtil.shiftForward(chars, startOffset, " \t");
    final int startLine = document.getLineNumber(startOffset);
    if (spaceEnd > endOffset || indentLevel <= 0 || startLine >= document.getLineCount() - 1 || chars.charAt(spaceEnd) == '\n') {
      return;
    }

    int endLine = startLine + 1;
    while (endLine < document.getLineCount() && document.getLineStartOffset(endLine) < endOffset) endLine++;

    final String indentString = StringUtil.repeatSymbol(' ', indentLevel);
    indentLines(document, startLine + 1, endLine - 1, indentString);
  }
private static void indentPlainTextBlock(final @NotNull Document document, final int startOffset, final int endOffset, final int indentLevel)