automatic tab indentation after new line (textEdit element)

veryQTguy

We are working on an Code Editor in our Company, for that we are using an textEdit element in our qml program.
What I am trying to achieve is that after a new Line an automatic Tab indentation is placed, like in popular IDEs like Visual Studio

this is the code I already have for that in my textedit element:

Keys.onPressed:
{
if(event.key === Qt.Key_Return || event.key === Qt.Key_Enter)
                {
                    pos1 = edit.cursorPosition //helping variable to reset actual position in line
                    console.log("lastTab nach enter: " + posDifference)

                    let spaces = "";
                    for(let i = 0; i < posDifference; i++)
                    {
                        spaces += " "
                        console.log("Iterator:" + i)
                    }
                }
}

onLineCountChanged: /
            {
                update()
                console.log("string to write:"+ spaces)
                edit.cursorPosition = edit.length
                edit.insert(edit.cursorPosition,spaces)
            }

the problem is that the blank spaces are placed in the previous line not in the new Line. I have no idea how to fix.
Note: posDifferent is the actual Position in the current line