Limit on the number of input lines in NSTextView?

Question

Cocoa

There is a text input field NSTextView. What you need:
1. limit the number of characters entered to 150 as much as possible;
2. limit the maximum number of lines to 4.
The first is quite simple. But on the second point I have a problem. I can count the number of lines of text in a field

NSLayoutManager *layoutManager = [NSTextView layoutManager];<br/>
NSUInteger numberOfLines, index, numberOfGlyphs = [layoutManager numberOfGlyphs];<br/>
NSRange lineRange;<br/>
<br/>
for (numberOfLines = 0, index = 0; index &lt; numberOfGlyphs; numberOfLines++){<br/>
 [layoutManager lineFragmentRectForGlyphAtIndex:index effectiveRange:&lineRange];<br/>
 index = NSMaxRange(lineRange);<br/>
}<br/>

But how to cut it to the required number of lines?