HTML Document Outline "Table Of Contents" Generator

I have this script that will read all the headers (h1-h6) in your HTML document and also HTML comment tags which are specially recognized, and it will create an HTML document "table of contents" (or outline) and insert it as a DIV within the document. This is for people with ESPECIALLY LONG HTML documents...it makes sense for this purpose.

The script is attached to this post in a zip. The zip archive has four JS files. 'htmlTOCgenerator.js' has all the meat of getting the nodes and generating the DOM nodes for the ToC. The other three have 'support' functions and are included. The 'colorContrasting.js' file is actually supposed to compute 'complementary' colors from random color generation. Why? Refresh the document each time, and the ToC has a different foreground (text) and background color, that's why. Breaks up the monotony. A large comment block inside 'htmlTOCgenerator.js' tells the document maker how to set up the HTML document for making this work.

In a first version, this script inserted the ToC ('table of contents') at the top of the document where the HTML comment tag "<!-- putTOChere -->" was placed/found.

Then I decided it was better to place the ToC DIV element to the left of the text, in a fixed block (does not scroll with text). The ToC DIV contents themselves are scrollable in case the contents would go beneath the bottom of the client window height--can't have that.

Click here to see an example of how it works:

I am having problems with it though.

1. The scrollbar on the ToC block always shows, even if the contents don't fill up the block. The CSS is set for 'overflow-y:scroll' but that does not mean the scrollbar does not show if there is no overflow. It would be nice to control that. Still have not figured it out.

For an example of not enough headers to fill out the height-specified (by necessity) fixed DIV block, see this page.

2. In my documents, the main body of text is all wrapped in a DIV with its right- and left-margins set to 'auto', so that when user widens or narrows the client window, the text is always centered. I need to stop the main body text from running behind the TOC during a narrowing of the client window. I thought setting the right margin of the ToC DIV should stop that. Anyway, that is a CSS styling problem, I suppose, although the CSS must be set through script (I do through script since the instructions don't require the document maker to set up CSS: too many instructions become annoying for anyone wanting utility in the script). And if you think frames are answer, that complicates matters and I believe it gets away from the eventuality when frames are deprecated.

3. I also want criticism on how to make this presentation/structuring/interaction of the ToC block better or workable.