(function($) {
	
	$.fn.spinButton = function(cfg){
		return this.each(function() {

			this.spinCfg = {
				minimum: cfg && !isNaN(parseFloat(cfg.minimum)) ? Number(cfg.minimum) : null,	// Fixes bug with minimum:0
				maximum: cfg && !isNaN(parseFloat(cfg.maximum)) ? Number(cfg.maximum) : null,
				step: cfg && cfg.step ? Number(cfg.step) : 1,
				page: cfg && cfg.page ? Number(cfg.page) : 10,
				upClass: cfg && cfg.upClass ? cfg.upClass : 'up',
				downClass: cfg && cfg.downClass ? cfg.downClass : 'down',
				reset: cfg && cfg.reset ? cfg.reset : this.value,
				delay: cfg && cfg.delay ? Number(cfg.delay) : 500,
				interval: cfg && cfg.interval ? Number(cfg.interval) : 100,
				callback: cfg && cfg.callback ? cfg.callback : null,
				_btn_width: 17,
				_btn_height: 17,
				_direction: null,
				_delay: null,
				_repeat: null
			};
			
			this.adjustValue = function(i){
				var v = (isNaN(this.value) ? this.spinCfg.reset : Number(this.value)) + Number(i);
				if (this.spinCfg.minimum !== null) v = Math.max(v, this.spinCfg.minimum);
				if (this.spinCfg.maximum !== null) v = Math.min(v, this.spinCfg.maximum);
				this.value = v;
				
				if (this.spinCfg.callback) {
					this.spinCfg.callback();
				}
			};
			
			$(this).attr("autocomplete", "off");
			
			$(this).addClass(cfg && cfg.spinClass ? cfg.spinClass : 'spin-button')
			.mousemove(function(e){
				// Determine which button mouse is over, or not (spin direction):
				var x = e.pageX || e.x;
				var y = e.pageY || e.y;
				var el = e.target || e.srcElement;
				var direction = 
					(x > coord(el,'offsetLeft') + el.offsetWidth - this.spinCfg._btn_width)
					? ((y < coord(el,'offsetTop') + el.offsetHeight - this.spinCfg._btn_height/2) ? 1 : -1) : 0;
				
				if (direction !== this.spinCfg._direction) {
					// Style up/down buttons:
					switch(direction){
						case 1: // Up arrow:
							$(this).removeClass(this.spinCfg.downClass).addClass(this.spinCfg.upClass);
							break;
						case -1: // Down arrow:
							$(this).removeClass(this.spinCfg.upClass).addClass(this.spinCfg.downClass);
							break;
						default: // Mouse is elsewhere in the textbox
							$(this).removeClass(this.spinCfg.upClass).removeClass(this.spinCfg.downClass);
					}
					// Set spin direction:
					this.spinCfg._direction = direction;
				}
			})
			
			.mouseout(function(){
				// Reset up/down buttons to their normal appearance when mouse moves away:
				$(this).removeClass(this.spinCfg.upClass).removeClass(this.spinCfg.downClass);
				this.spinCfg._direction = null;
			})
			
			.mousedown(function(e){
				if (this.spinCfg._direction != 0) {
					// Respond to click on one of the buttons:
					var self = this;
					var adjust = function() {
						self.adjustValue(self.spinCfg._direction * self.spinCfg.step);
					};
					adjust();
					
					// Initial delay before repeating adjustment
					self.spinCfg._delay = window.setTimeout(function() {
						adjust();
						// Repeat adjust at regular intervals
						self.spinCfg._repeat = window.setInterval(adjust, self.spinCfg.interval);
					}, self.spinCfg.delay);
				}
			})
			
			.mouseup(function(e){
				// Cancel repeating adjustment
				window.clearInterval(this.spinCfg._repeat);
				window.clearTimeout(this.spinCfg._delay);
			})
			
			.dblclick(function(e) {
				if ($.browser.msie)
					this.adjustValue(this.spinCfg._direction * this.spinCfg.step);
			})
			
			.keydown(function(e){
				// Respond to up/down arrow keys.
				switch(e.keyCode){
					case 38: this.adjustValue(this.spinCfg.step);  break; // Up
					case 40: this.adjustValue(-this.spinCfg.step); break; // Down
					case 33: this.adjustValue(this.spinCfg.page);  break; // PageUp
					case 34: this.adjustValue(-this.spinCfg.page); break; // PageDown
					default:
						if ( (e.keyCode >= 48 && e.keyCode <= 57) && this.spinCfg.callback ) {
							$(this).val( $(this).val() + (e.keyCode - 48) );
							this.spinCfg.callback();
							e.preventDefault();
						}
					break;
				}
			})
	
			.bind("mousewheel", function(e){
				// Respond to mouse wheel in IE. (It returns up/dn motion in multiples of 120)
				if (e.wheelDelta >= 120)
					this.adjustValue(this.spinCfg.step);
				else if (e.wheelDelta <= -120)
					this.adjustValue(-this.spinCfg.step);
				
				e.preventDefault();
			})
			
			.change(function(e){
				this.adjustValue(0);
			});
			
			if (this.addEventListener) {
				// Respond to mouse wheel in Firefox
				this.addEventListener('DOMMouseScroll', function(e) {
					if (e.detail > 0)
						this.adjustValue(-this.spinCfg.step);
					else if (e.detail < 0)
						this.adjustValue(this.spinCfg.step);
					
					e.preventDefault();
				}, false);
			}
		});
		
		function coord(el,prop) {
			var c = el[prop], b = document.body;
			
			while ((el = el.offsetParent) && (el != b)) {
				c += el[prop];
				//if (!$.browser.msie || parseInt($.browser.version) >= 7 || (el.currentStyle.position != 'relative'))
					//c += el[prop];
			}
			return c;
		}
	};
})(jQuery);