// Place your application-specific JavaScript functions and classes here
// This file is automatically included by javascript_include_tag :defaults

// When object is available, do function fn.
function when(obj, fn) {
  if (Object.isString(obj)) obj = /^[\w-]+$/.test(obj) ? $(obj) : $(document.body).down(obj);
  if (Object.isArray(obj) && !obj.length) return;
  if (obj) fn(obj);
}

Event.observe(window, 'load', function(){
    $$('.Scrollbar-Up').invoke('observe', 'mouseover', function(event){
			scroller.startScroll(0, 15);
    });
    $$('.Scrollbar-Up').invoke('observe', 'mouseout', function(event){
			scroller.stopScroll();
    });
    $$('.Scrollbar-Down').invoke('observe', 'mouseover', function(event){
			scroller.startScroll(0, -15);
    });
    $$('.Scrollbar-Down').invoke('observe', 'mouseout', function(event){
			scroller.stopScroll();
    });
});

document.observe('dom:loaded', function() {

  when('notice', function(notice) {
    new Effect.Fade(notice, {delay: 3});
  });
  
  when('error', function(notice) {
    new Effect.Fade(notice, {delay: 3});
  });
	
	when('files_list', function() {
		var multi_selector = new MultiSelector($('files_list'));
		multi_selector.addElement($('my_file_element'));
	});
});

var scroller = null;
window.onload = function () {
  when("Scroller-1", function(el) {
    scroller = new jsScroller(el, 100, 400);
  });
}

//Written by Nathan Faubion: http://n-son.com
//Use this or edit how you want, just give me
//some credit!
function jsScroller (o, w, h) {
	var self = this;
	var list = o.getElementsByTagName("div");
	for (var i = 0; i < list.length; i++) {
		if (list[i].className.indexOf("Scroller-Container") > -1) {
			o = list[i];
		}
	}
	
	//Private methods
	this._setPos = function (x, y) {
		if (x < this.viewableWidth - this.totalWidth) 
			x = this.viewableWidth - this.totalWidth;
		if (x > 0) x = 0;
		if (y < this.viewableHeight - this.totalHeight) 
			y = this.viewableHeight - this.totalHeight;
		if (y > 0) y = 0;
		this._x = x;
		this._y = y;
		with (o.style) {
			left = this._x +"px";
			top  = this._y +"px";
		}
	};
	
	//Public Methods
	this.reset = function () {
		this.content = o;
		this.totalHeight = o.offsetHeight;
		this.totalWidth	 = o.offsetWidth;
		this._x = 0;
		this._y = 0;
		with (o.style) {
			left = "0px";
			top  = "0px";
		}
	};
	this.scrollBy = function (x, y) {
		this._setPos(this._x + x, this._y + y);
	};
	this.scrollTo = function (x, y) {
		this._setPos(-x, -y);
	};
	this.stopScroll = function () {
		if (this.scrollTimer) window.clearInterval(this.scrollTimer);
	};
	this.startScroll = function (x, y) {
		this.stopScroll();
		this.scrollTimer = window.setInterval(
			function(){ self.scrollBy(x, y); }, 40
		);
	};
	this.swapContent = function (c, w, h) {
		o = c;
		var list = o.getElementsByTagName("div");
		for (var i = 0; i < list.length; i++) {
			if (list[i].className.indexOf("Scroller-Container") > -1) {
				o = list[i];
			}
		}
		if (w) this.viewableWidth  = w;
		if (h) this.viewableHeight = h;
		this.reset();
	};
	
	//variables
	this.content = o;
	this.viewableWidth  = w;
	this.viewableHeight = h;
	this.totalWidth	 = o.offsetWidth;
	this.totalHeight = o.offsetHeight;
	this.scrollTimer = null;
	this.reset();
};


function MultiSelector( list_target, max ){

	// Where to write the list
	this.list_target = list_target;
	// How many elements?
	this.count = 0;
	// How many elements?
	this.id = 0;
	// Is there a maximum?
	if( max ){
		this.max = max;
	} else {
		this.max = -1;
	};
	
	/**
	 * Add a new file input element
	 */
	this.addElement = function( element ){

		// Make sure it's a file input element
		if( element.tagName == 'INPUT' && element.type == 'file' ){

			// Element name -- what number am I?
			element.name = 'file_' + this.id++;

			// Add reference to this object
			element.multi_selector = this;

			// What to do when a file is selected
			element.onchange = function(){

				// New file input
				var new_element = document.createElement( 'input' );
				new_element.type = 'file';

				// Add new element
				this.parentNode.insertBefore( new_element, this );

				// Apply 'update' to element
				this.multi_selector.addElement( new_element );

				// Update list
				this.multi_selector.addListRow( this );

				// Hide this: we can't use display:none because Safari doesn't like it
				this.style.position = 'absolute';
				this.style.left = '-1000px';

			};
			// If we've reached maximum number, disable input element
			if( this.max != -1 && this.count >= this.max ){
				element.disabled = true;
			};

			// File element counter
			this.count++;
			// Most recent element
			this.current_element = element;
			
		} else {
			// This can only be applied to file input elements!
			alert( 'Error: not a file input element' );
		};

	};

	/**
	 * Add a new row to the list of files
	 */
	this.addListRow = function( element ){

		// Row div
		var new_row = document.createElement( 'div' );

		// Delete button
		var new_row_button = document.createElement( 'input' );
		new_row_button.type = 'button';
		new_row_button.value = 'Delete';

		// References
		new_row.element = element;

		// Delete function
		new_row_button.onclick= function(){

			// Remove element from form
			this.parentNode.element.parentNode.removeChild( this.parentNode.element );

			// Remove this row from the list
			this.parentNode.parentNode.removeChild( this.parentNode );

			// Decrement counter
			this.parentNode.element.multi_selector.count--;

			// Re-enable input element (if it's disabled)
			this.parentNode.element.multi_selector.current_element.disabled = false;

			// Appease Safari
			//    without it Safari wants to reload the browser window
			//    which nixes your already queued uploads
			return false;
		};

		// Set row value
		new_row.innerHTML = element.value;

		// Add button
		new_row.appendChild( new_row_button );

		// Add it to the list
		this.list_target.appendChild( new_row );
		
	};

};