Useful NSTextView extensions

NSTextViewExtensions.swift

extension NSTextView {
    func rectForRange(range: NSRange) -> NSRect? {
        guard let layout = self.layoutManager, container = self.textContainer else {return nil}
        let rng = layout.glyphRangeForCharacterRange(range, actualCharacterRange: nil)
        let rct = layout.boundingRectForGlyphRange(rng, inTextContainer: container)
        return NSOffsetRect(rct, self.textContainerOrigin.x, self.textContainerOrigin.y)
    }
    
    func rectForSelectedRange() -> NSRect? {
        return rectForRange(self.selectedRange())
    }
    
    func scrollAndHighlight(toLine ln: Int) {
        scroll(toLine: ln) { (range) -> () in
            self.setSelectedRange(range)
        }
    }

    func scroll(toLine ln: Int, withAction f: (range:NSRange) -> ()) {
        guard let layout = self.layoutManager else {return}
        guard ln >= 1 else {return}
        
        let numGlyphs = layout.numberOfGlyphs
        var i = 0
        var cl = 1
        var targetRange = NSRange()

        while i < numGlyphs {
            let _ = layout.lineFragmentRectForGlyphAtIndex(i, effectiveRange: &targetRange)
            
            if cl == ln {
                self.scrollRangeToVisible(targetRange)
                return f(range: targetRange)
            }
            
            i += targetRange.length
            cl++
        }
    }
}