Indent in TOC

Hi,
I can not manage controlling the space between chapter/section number and chapter/section title + customizing the indent of the line depending on the section Level in TOC…

Actually what I’d like to get is something like this:

X.   Chapter
	x.1            Section Level1
		x.1.1 Section Level 2
			x.1.1.1 Section Level 3

where the indent is constant but the space between Lavel 1 section number and title is not the same than the space for Level 2 section or Level 3 section…

Could anyone help me to find out which parameter shall be used and which condition (if level1 > xxx otherwise …) shall be applied to achieve that?
Many thanks and regards,
JF