// requires global.js -- NEEDS Function.prototype.closure = function(obj){...} from global.js

function MLoader(map, statusElement, textElement, barElement, fillElement, cancelButton, tally)
{
    this.map = map;
    this.statusElement = statusElement;
    this.bar = barElement;
    this.fill = fillElement;
    this.textElement = textElement;
    this.cancelButton = cancelButton;
	this.tally = tally
}
MLoader.prototype.map = null;
MLoader.prototype.statusElement = null;
MLoader.prototype.textElement = null;
MLoader.prototype.cancelButton = null;
MLoader.prototype.bar = null;
MLoader.prototype.fill = null;
MLoader.prototype.counter = 0;
MLoader.prototype.show = function (text, allowCancel)
{
    this.map.disableDragging();
    this.statusElement.style.display = "";
    this.statusElement.style.left = (document.body.clientWidth - 160)/2 + "px";
    this.textElement.innerHTML = text;
    if (allowCancel)
        this.cancelButton.style.display = "";
    else
        this.cancelButton.style.display = "none";
    this.counter++;
}
MLoader.prototype.hide = function (force)
{
    if (force)
        this.counter = 0;
    else if (this.counter > 0)
        this.counter--;
        
    if (this.counter == 0)
    {
        this.fill.style.width = "1px";
        this.statusElement.style.display = "none";
        this.map.enableDragging();
    }
}
MLoader.prototype.queue = null;
MLoader.prototype.add = function (o, f, a)
{
    if (!this.queue)
        this.queue = new Array();
        
    this.queue[this.queue.length] = _MOneTimeClosure(o,f,a);
}
MLoader.prototype.queueCounter = 0;
MLoader.prototype.execute = function ()
{
    
	if ((this.queueCounter > 0) && (this.queue)) {
        this.fill.style.width = (100 * this.queueCounter / this.queue.length) + "%";
		this.tally.innerHTML = this.queueCounter + ' records of ' + this.queue.length;
	}
	else {
        this.fill.style.width = "1px";
	}
    
    var stopAt = this.queueCounter + 10;
    while ((this.queue) && (this.queueCounter < this.queue.length) && (this.queueCounter < stopAt))
    {
        this.queue[this.queueCounter]();
        this.queue[this.queueCounter++] = null;
    }
    
    if ((this.queue) && (this.queueCounter < this.queue.length))
    {
        setTimeout(this.execute.closure(this), 50);
    }
    else
    {
        for (var i = 0; (this.queue) && (i < this.queue.length); i++)
            this.queue[i] = null;
        this.queue = null;
        this.queueCounter = 0;
        this.hide(true);
    }
}
MLoader.prototype.cancel = function ()
{
    for (var i = 0; (this.queue) && (i < this.queue.length); i++)
        this.queue[i] = null;
    this.queue = null;
    this.queueCounter = 0;
    this.hide(true);
}

// Executes once and removes all references
function _MOneTimeClosure (h, f, a){
        return (function() {
            hf = f;
            hf(a);
            a = null;
            hf = null;
            h = null;
        })
    }