var startX,startY,endX,endY;
var selectionTop,selectionLeft,selectionBottom,selectionRight;
var ErrMsg = "The warehouse hasn't got sufficient stock to fulfill this request of items below. Please reduce your quantity\n";
var NewErrMsg = '';
function checkRange(point,smallLimit,largeLimit){
	var returnValue = false;
	if (point >= smallLimit && point <= largeLimit){
		returnValue = true;
	}
	return returnValue;
}

function addSelection(obj){
	$(obj).addClass("selected");
}

function clearSelection(){
	$(".selectable").removeClass("selected");
}

function setSelection(){
	selectionTop = Math.min(startY,endY);
	selectionLeft = Math.min(startX,endX);
	selectionBottom = Math.max(startY,endY);
	selectionRight = Math.max(startX,endX);
	//Debug
	//appendOutput("output","selection:\ntop:" + selectionTop + "\nleft:" + selectionLeft + "\nbottom:" + selectionBottom + "\nright:" + selectionRight);
}

function checkSelection(){
	var localTop = $(this).offset().top;
	var localLeft = $(this).offset().left;
	var localBottom = $(this).offset().top + $(this).height();
	var localRight = $(this).offset().left + $(this).width();
	//Debug
	//appendOutput("output","local(" + this.id + "):\ntop:" + localTop + "\nleft:" + localLeft + "\nbottom:" + localBottom + "\nright:" + localRight);
	//Fully selected case
	if (localTop >= selectionTop && localLeft >= selectionLeft && localBottom <= selectionBottom && localRight <= selectionRight) {
		addSelection(this);
		return;
	}
	//Corner cases
	if ((checkRange(selectionTop,localTop,localBottom) || checkRange(selectionBottom,localTop,localBottom))
		&& (checkRange(selectionLeft,localLeft,localRight) || checkRange(selectionRight,localLeft,localRight))) {
		addSelection(this);
		return;
	}
	//Vertical border cases
	if ((checkRange(selectionLeft,localLeft,localRight) || checkRange(selectionRight,localLeft,localRight))
		&& selectionTop <= localTop && selectionBottom >= localBottom) {
		addSelection(this);
		return;
	}
	//Horizontal border cases
	if ((checkRange(selectionTop,localTop,localBottom) || checkRange(selectionBottom,localTop,localBottom))
		&& selectionLeft <= localLeft && selectionRight >= localRight) {
		addSelection(this);
		return;
	}
}

//Place selection rectangle
function placeSelectionRectangle(startX,startY){
	var obj = document.getElementById("selectionCanvas");
	$(obj).css("display","block").css("left",startX).css("top",startY).height(0).width(0);
}

//Size selection rectangle
function sizeSelectionRectangle(posX,posY){
	if (startX && startY) {
		var obj = document.getElementById("selectionCanvas");
		var selectionTop = Math.min(startY,posY);
		var selectionLeft = Math.min(startX,posX);
		var selectionHeight = Math.abs(startY-posY);
		var selectionWidth = Math.abs(startX-posX);
		//appendOutput("output","T : " + selectionTop + " L : " + selectionLeft + " H : " + selectionHeight + " W : " + selectionWidth);
		$(obj).css("top",selectionTop).css("left",selectionLeft).height(selectionHeight).width(selectionWidth);
	}
}

//Remove selection rectangle
function removeSelectionRectangle(){
	var obj = document.getElementById("selectionCanvas");
	$(obj).css("display","none").css("left",0).css("top",0).height(0).width(0);
}

function initialiseSelectionGrid(){
    //Null start and end points
    startX = null;
    startY = null;
    endX = null;
    endY = null;		
	//Disable selection on the container
	$("#selectcontainer").bind('selectstart', function(e){
        return false;
    });
	
	//Drag select start event
	$("#selectcontainer").bind("mousedown",function(e){
		clearSelection();
		if (e.button > 1) {return false};
		startX = e.pageX;
		startY = e.pageY;
		placeSelectionRectangle(startX,startY);
	});
	
	//Drag select end event
	$("#selectcontainer").add("#selectionCanvas").bind("mouseup",function(e){
		if (e.button > 1) {return false};
		endX = e.pageX;
		endY = e.pageY;
		removeSelectionRectangle();
		setSelection();
		$(".selectable").each(checkSelection);
	});
	
	$("#selectcontainer").bind("click",function(e){
		removeSelectionRectangle();
	});
	
	//Track mouse position
	$("#selectcontainer").bind("mousemove",function(e){
		var posX = e.pageX;
		var posY = e.pageY;
		sizeSelectionRectangle(posX,posY);
		//Debug
		//writeOutput("mousepos","X : " + posX + " Y : " + posY);
	});
	
	//Check for key presses
	$(".selectable").bind("keydown",function(e){
		//<ESC> key exit
		if(e.keyCode == 27){
			clearSelection();
		}
		//<ENTER> key save
		if(e.keyCode == 13){
			updateSelectionValues(this);
			clearSelection();
		}
		//<TAB> key save
		if(e.keyCode == 9){
			updateSelectionValues(this);
			clearSelection();
		}		
	});
	
	//Check for blur event save
	$(".selectable").bind("blur",function(e){
		//Debug
		//appendOutput("output","Blur Saving (Current Object Only)");
		saveSelectionValue(this,this.value)
		clearSelection();
	});
}

//Wrapping function for <ENTER> key save
function updateSelectionValues(obj){
	NewErrMsg = '';
	if ($(".selected").size() > 0){
		//Debug
		//appendOutput("output","Enter Saving (All Selected Objects)");
		$(".selected").each(function(){
			saveSelectionValue(this,obj.value);
		});
	}
	else {
		//Debug
		//appendOutput("output","Enter Saving (Current Object Only)");
		saveSelectionValue(obj,obj.value);
	}
	if(NewErrMsg != '')
	{
		alert(ErrMsg + NewErrMsg);	
	}
}

//The save function for individual selectable boxes
function saveSelectionValue(obj,value){
	//Debug
	//appendOutput("output","Saved: " + obj.id + " (" + value + ")");
	obj.value = value;
	var ObjID = obj.id;
	var ArrObjID = ObjID.split('_');
	var r = ArrObjID[1];
	var RC = ArrObjID[1] + '_' + ArrObjID[2];
	var OrderType = document.getElementById('txtOrderType').value;
	var StockID = document.getElementById('StockID_'+RC).value;
	var StockCount = document.getElementById('StockCount_'+RC).value;
	var StockDesc = document.getElementById('StockDesc_'+RC).value;
	
	StockCount = eval(StockCount);
	
	//alert(obj.value);
	var Qty = 0;
	var EqQty = 0;
	
	if(obj.value == '')
	{
		obj.value = 0	
	}
	
	if (eval(obj.value) > StockCount)
	{
		NewErrMsg = NewErrMsg + StockDesc + '\n';
//		obj.value = 0;
	}
	if(obj.value != '')
	{
		if (eval(obj.value) < StockCount)
		{
			var ColCount = document.getElementById("txtCol_"+r).value;
			var eqname = 'txtOrderItemQtyTotal_' + r + '_' + ColCount;
			var eq = document.getElementById(eqname);
			for (var k=1;k<ColCount;k++)
			{
				Qty = document.getElementById("txtOrderItemQty_" + r + '_' + k).value;
				if(Qty == '')
				{
					Qty = 0;	
				}
				EqQty = eval(EqQty) + eval(Qty);
			}
			//alert(EqQty);
			eq.value = EqQty; 
			SaveOrder(obj, StockID, OrderType);
		}
	}
}