SKMultilineLabel.swift

import SpriteKit

class SKMultilineLabelNode: SKNode {
	//props
	var labelWidth:Int {didSet {update()}}
	var labelHeight:Int = 0
	var text:String {didSet {update()}}
	var fontName:String {didSet {update()}}
	var fontSize:CGFloat {didSet {update()}}
	var pos:CGPoint {didSet {update()}}
	var fontColor:SKColor {didSet {update()}}
	var leading:CGFloat {didSet {update()}}
	var alignment:SKLabelHorizontalAlignmentMode {didSet {update()}}
	var dontUpdate = false
	var shouldShowBorder:Bool = false {didSet {update()}}
	//display objects
	var rect:SKShapeNode?
	var labels:[SKLabelNode] = []
	
	init(text:String, labelWidth:Int, pos:CGPoint, fontName:String="Helvetica",fontSize:CGFloat=10,fontColor:SKColor=SKColor.blackColor(),alignment:SKLabelHorizontalAlignmentMode = .Left, shouldShowBorder:Bool = false)
	{
		self.text = text
		self.labelWidth = labelWidth
		self.pos = pos
		self.fontName = fontName
		self.fontSize = fontSize
		self.fontColor = fontColor
		self.leading = fontSize
		self.shouldShowBorder = shouldShowBorder
		self.alignment = alignment
		
		super.init()
		
		self.update()
	}
	
	required init?(coder aDecoder: NSCoder) {
		fatalError("init(coder:) has not been implemented")
	}
	
	func getLinesArrayOfStringInLabel(text:NSString, fontName:String, fontSize:CGFloat, width:CGFloat) -> [String] {
		
		
		let myFont:CTFontRef = CTFontCreateWithName(fontName, fontSize, nil)
		let attStr:NSMutableAttributedString = NSMutableAttributedString(string: text as String)
		attStr.addAttribute(String(kCTFontAttributeName), value:myFont, range: NSMakeRange(0, attStr.length))
		let frameSetter:CTFramesetterRef = CTFramesetterCreateWithAttributedString(attStr as CFAttributedStringRef)
		let path:CGMutablePathRef = CGPathCreateMutable()
		CGPathAddRect(path, nil, CGRectMake(0, 0, width, 100000))
		let frame:CTFrameRef = CTFramesetterCreateFrame(frameSetter, CFRangeMake(0, 0), path, nil)
		let lines = CTFrameGetLines(frame) as NSArray
		var linesArray = [String]()
		
		for line in lines {
			let lineRange = CTLineGetStringRange(line as! CTLine)
			let range:NSRange = NSMakeRange(lineRange.location, lineRange.length)
			let lineString = text.substringWithRange(range)
			linesArray.append(lineString as String)
		}
		return linesArray
	}
	
	func update() {
		if (dontUpdate) {return}
		if (labels.count>0) {
			for label in labels {
				label.removeFromParent()
			}
			labels = []
		}
		
		
		let lines = self.getLinesArrayOfStringInLabel(text, fontName: self.fontName , fontSize: self.fontSize, width: CGFloat(self.labelWidth))
		var lineCount = 0
		
		for line in lines {
			
			lineCount++
			let label = SKLabelNode(fontNamed: fontName)
			
			label.name = "line\(lineCount)"
			label.horizontalAlignmentMode = alignment
			label.fontSize = fontSize
			label.fontColor = self.fontColor
			label.text = line
			var linePos = pos
			if (alignment == .Left) {
				linePos.x -= CGFloat(labelWidth / 2)
			} else if (alignment == .Right) {
				linePos.x += CGFloat(labelWidth / 2)
			}
			linePos.y += leading * CGFloat(-lineCount) * 2
			label.position = CGPointMake( linePos.x , linePos.y )
			self.addChild(label)
			labels.append(label)
		}
		
		labelHeight = Int(CGFloat(lineCount) * leading * 2)
		showBorder()
	}

	
	func showBorder() {
		if (!shouldShowBorder) {return}
		if let rect = self.rect {
			self.removeChildrenInArray([rect])
		}
		self.rect = SKShapeNode(rectOfSize: CGSize(width: labelWidth, height: labelHeight))
		if let rect = self.rect {
			rect.strokeColor = SKColor.whiteColor()
			rect.lineWidth = 1
			rect.position = CGPoint(x: pos.x, y: pos.y - (CGFloat(labelHeight) / 2.0))
			self.addChild(rect)
		}
	}
}