package {
	
	import flash.display.DisplayObject;
	import flash.display.Stage;
	import flash.display.StageScaleMode;
	import flash.display.StageAlign;
	import flash.events.Event;
	import flash.utils.Dictionary;
	
	public class StageAlignTool{
		
		//nine slices for pinning objects
		public static const TL:uint = 1;
		public static const TC:uint = 2;
		public static const TR:uint = 3;
		public static const ML:uint = 4;
		public static const MC:uint = 5;
		public static const MR:uint = 6;
		public static const BL:uint = 7;
		public static const BC:uint = 8;
		public static const BR:uint = 9;
		
		private static var _stage:Stage
		private static var _stageW:uint;
		private static var _stageH:uint;
		private static var _minW:uint
		private static var _minH:uint
		private static var _registeredObjects:Dictionary;
		
		//function StageAlignTool(){}
		
		
		//inital call, sets stage and minimum stage size
		public static function init($stage:Stage, $minW:uint = 1024, $minH:uint = 768):void{
			_stage = $stage;
			_stageW = _stage.stageWidth;
			_stageH = _stage.stageHeight;
			_minW = $minW;
			_minH = $minH;
			_stage.scaleMode = StageScaleMode.NO_SCALE;
			_stage.align = StageAlign.TOP_LEFT;
			
			_registeredObjects = new Dictionary();
			
			_stage.addEventListener(Event.RESIZE, onStageResize);
		}
		
		//if you need to stop positioning objects for some reason
		public static function kill():void{
			_stage.removeEventListener(Event.RESIZE, onStageResize);
		}
		
		//used to add a display object to the list of objects that will be laid out
		//if stayRelative == true the object will retain it's original offset from the stage (when registered);
		//if stayRelative == false the object will pin to whichever corner is set by $loc
		public static function registerLocation($disp:DisplayObject, $loc:uint, $stayRelative:Boolean = false):void{
			if (_stage){
				
				_registeredObjects[$disp] = {location:$loc, stayRelative:$stayRelative, ogX:$disp.x, ogY:$disp.y};
				onStageResize(null);
				
			}else{
				trace("stage not set");
			}
		}
		
		//meat
		private static function onStageResize(e:Event = null):void{
			//trace(e);
			var sw:uint = (_stage.stageWidth >= _minW) ? _stage.stageWidth : _minW;
			var sh:uint = (_stage.stageHeight >= _minH) ? _stage.stageHeight : _minH;
			
			//if (sw >= _minW && sh >= _minH){
			
				for (var $disp in _registeredObjects){
					
					trace($disp.name, _registeredObjects[$disp].location, _registeredObjects[$disp].stayRelative);
					switch (_registeredObjects[$disp].location){
						
						case TL:
							if (_registeredObjects[$disp].stayRelative){
								//x doesn't change
								//y doesn't change
							}else{
								$disp.x = $disp.y = 0;
							}
							break;
						case TC:
							if (_registeredObjects[$disp].stayRelative){
								$disp.x = (sw/2) - (_stageW / 2) + _registeredObjects[$disp].ogX;
								//y doesn't change
							}else{
								$disp.x = (sw / 2) - ($disp.width / 2);
								$disp.y = 0;
							}
							break;
						case TR:
							if (_registeredObjects[$disp].stayRelative){
								$disp.x = sw - _stageW + _registeredObjects[$disp].ogX;
								//y doesn't change
								
							}else{
								$disp.x = (sw - $disp.width);
								$disp.y = 0;
							}
							break;
						case ML:
							if (_registeredObjects[$disp].stayRelative){
								//x doesn't change
								$disp.y = (sh/2) - (_stageH / 2) + _registeredObjects[$disp].ogY;
							}else{
								$disp.x = 0;
								$disp.y = (sh / 2) - ($disp.height / 2);
							}
							break;
						case MC:
							if (_registeredObjects[$disp].stayRelative){
								$disp.x = (sw/2) - (_stageW / 2) + _registeredObjects[$disp].ogX;
								$disp.y = (sh/2) - (_stageH / 2) + _registeredObjects[$disp].ogY;
							}else{
								$disp.x = (sw / 2) - ($disp.width / 2);
								$disp.y = (sh / 2) - ($disp.height / 2);
							}
							break;
						case MR:
							if (_registeredObjects[$disp].stayRelative){
								$disp.x = sw - _stageW + _registeredObjects[$disp].ogX;
								$disp.y = (sh/2) - (_stageH / 2) + _registeredObjects[$disp].ogY;
							}else{
								$disp.x = (sw - $disp.width);
								$disp.y = (sh / 2) - ($disp.height / 2);
							}
							break;
						case BL:
							if (_registeredObjects[$disp].stayRelative){
								//x doesn't change
								$disp.y = sh - _stageH + _registeredObjects[$disp].ogY;
							}else{
								$disp.x = 0;
								$disp.y = (sh - $disp.height);
							}
							break;
						case BC:
							if (_registeredObjects[$disp].stayRelative){
								$disp.x = (sw/2) - (_stageW / 2) + _registeredObjects[$disp].ogX;
								$disp.y = sh - _stageH + _registeredObjects[$disp].ogY;
							}else{
								$disp.x = (sw / 2) - ($disp.width / 2);
								$disp.y = (sh - $disp.height);
							}
							break;
						case BR:
							if (_registeredObjects[$disp].stayRelative){
								$disp.x = sw - _stageW + _registeredObjects[$disp].ogX;
								$disp.y = sh - _stageH + _registeredObjects[$disp].ogY;
							}else{
								$disp.x = (sw - $disp.width);
								$disp.y = (sh - $disp.height);
							}
							break;
						
					}//switch
					
				}//for
			//}//if min width
			
		}//onStageResize
		
		
		
	}//class
}//package