Something like that sounds possible using javascript, but it depends a bit on the structure of your html and whether or not you want to break paragraphs or just move the next paragraph to the next page if it doesn´t fit
So the simplest example, not breaking paragraphs / html elements with a flat html structure (no nested divs, columns, etc) like:
<div class="document">
<h1>title</h1>
<p>texts</p>
<h2>subtitle</h2>
<p>texts</p>
...
<p>texts</p>
</div>
would be to do something like:
height = 0
loop through all direct child elements of .document
{
if ( (height + element_height) > page_height)
{
add page_break_element before current element
height = 0
}
height = height + element_height
}
I´d use jquery because it makes it easy to loop through the elements, measure heights, etc.
I guess breaking paragraphs would be possible as well, but a lot of extra work.