Treeview make item and all children shift right (become child of previous item)

[corgano]

I can't explain easily what i want to do, so i made a picture:

What i want to do is to specify a treeview item, and then be able to move it right to be a child of the previous item, or left to do the opposite (make a child into a sibling). I also want to move and child items of the target with it, like in the bottom half of the above image depicts. However I didn't see any functions in the help file to move items around. All i want is a button that when pressed, makes the selected item and any of selected item's children move one layer to the right / left. Does anyone know how?

Edit: something along the lines of _GUICtrlTreeView_Level but SET level

Edited June 7, 2017 by corgano