/**
*  jquery.spin-button
*  (c) 2008 Semooh (http://semooh.jp/)
*
*  Dual licensed under the MIT (MIT-LICENSE.txt)
*  and GPL (GPL-LICENSE.txt) licenses.
*
**/
(function($){
	$.fn.extend({
		spin: function(opt){
			return this.each(function(){
				opt = $.extend({
						imageBasePath: '/img/spin/',
						spinBtnImage: 'spin-button.png',
						spinUpImage: 'spin-up.png',
						spinDownImage: 'spin-down.png',
						interval: 1,
						max: null,
						min: null,
						timeInterval: 500,
						timeBlink: 200
					}, opt || {});
				
				var txt = $(this);
				
				var spinBtnImage = opt.imageBasePath+opt.spinBtnImage;
				var btnSpin = new Image();
				btnSpin.src = spinBtnImage;
				var spinUpImage = opt.imageBasePath+opt.spinUpImage;
				var btnSpinUp = new Image();
				btnSpinUp.src = spinUpImage;
				var spinDownImage = opt.imageBasePath+opt.spinDownImage;
				var btnSpinDown = new Image();
				btnSpinDown.src = spinDownImage;
				
				var btn = $(document.createElement('img'));
				btn.attr('src', spinBtnImage);
				btn.css({cursor: 'pointer', padding: 0, margin: '0 0 0 2px'});
				txt.after(btn);
				txt.css({marginRight:0, paddingRight:0});
				
				function spin(vector){
					var val = txt.val();
					if(!isNaN(val)){
						val = parseFloat(val) + (vector*opt.interval);
						if(opt.min!=null && val<opt.min) val=opt.min;
						if(opt.min!=null && val>opt.max) val=opt.max;
						if(val != txt.val()){
							txt.val(val);
							txt.change();
							src = (vector > 0 ? spinUpImage : spinDownImage);
							btn.attr('src', src);
							if(opt.timeBlink<opt.timeInterval)
								setTimeout(function(){btn.attr('src', spinBtnImage);}, opt.timeBlink);
						}
					}
				}
				
				btn.mousedown(function(e){
					var pos = e.pageY - btn.offset().top;
					var vector = (btn.height()/2 > pos ? 1 : -1);
					(function(){
						spin(vector);
						var tk = setTimeout(arguments.callee, opt.timeInterval);
						$(document).one('mouseup', function(){
							clearTimeout(tk); btn.attr('src', spinBtnImage);
						});
					})();
					return false;
				});
			});
		}
	});
})(jQuery);