(function( $ ){
	$.fn.qrcode = function(options) {
		// if options is string, 
		if( typeof options === 'string' ){
			options	= { text: options };
		}
		//�����ĵĵ���
        options.text = utf16to8(options.text);
		// set default values
		// typenumber < 1 for automatic calculation
		options	= $.extend( {}, {
			render		: "canvas",
			width		: 256,
			height		: 256,
			typenumber	: -1,
			correctlevel	: qrerrorcorrectlevel.h,
            background : "#ffffff",
            foreground : "#000000",
            logo : ""
		}, options);

		var createcanvas	= function(){
			// create the qrcode itself
			var qrcode	= new qrcode(options.typenumber, options.correctlevel);
			qrcode.adddata(options.text);
			qrcode.make();

			// create canvas element
			var canvas	= document.createelement('canvas');
			canvas.width	= options.width;
			canvas.height	= options.height;
			var ctx		= canvas.getcontext('2d');

			// compute tilew/tileh based on options.width/options.height
			var tilew	= options.width  / qrcode.getmodulecount();
			var tileh	= options.height / qrcode.getmodulecount();

			// draw in the canvas
			for( var row = 0; row < qrcode.getmodulecount(); row++ ){
				for( var col = 0; col < qrcode.getmodulecount(); col++ ){
					ctx.fillstyle = qrcode.isdark(row, col) ? options.foreground : options.background;
					var w = (math.ceil((col+1)*tilew) - math.floor(col*tilew));
					var h = (math.ceil((row+1)*tilew) - math.floor(row*tilew));
					ctx.fillrect(math.round(col*tilew),math.round(row*tileh), w, h);  
				}	
			}
            if(options.logo != "")
		   {
		       var image = new image(); 
                image.onload = function() { 
        		       var w = image.width;
        		       var h = image.height;
		           ctx.drawimage(image,(options.width-w)/2,(options.height-h)/2);
                } 
                image.src = options.logo;
		   }
			// return just built canvas
			return canvas;
		}

		// from jon-carlos rivera (https://github.com/imbcmdth)
		var createtable	= function(){
			// create the qrcode itself
			var qrcode	= new qrcode(options.typenumber, options.correctlevel);
			qrcode.adddata(options.text);
			qrcode.make();
			
			// create table element
			var $table	= $('<table></table>')
				.css("width", options.width+"px")
				.css("height", options.height+"px")
				.css("border", "0px")
				.css("border-collapse", "collapse")
				.css('background-color', options.background);
			// compute tiles percentage
			var tilew	= options.width / qrcode.getmodulecount();
			var tileh	= options.height / qrcode.getmodulecount();

			// draw in the table
			for(var row = 0; row < qrcode.getmodulecount(); row++ ){
				var $row = $('<tr></tr>').css('height', tileh+"px").appendto($table);
				
				for(var col = 0; col < qrcode.getmodulecount(); col++ ){
					$('<td></td>')
						.css('width', tilew+"px")
						.css('background-color', qrcode.isdark(row, col) ? options.foreground : options.background)
						.appendto($row);
				}	
			}
			// return just built table
			if(options.logo != "")
			{
			       $table.css("position", "absolute").css("z-index", "0");    
			       //������table������logo��ĸ�����
			       var divcontainer = $('<div></div>')
        			    .css("width", options.width+"px")
        			    .css("height", options.height+"px")
        			    .css("position", "relative");
			
			         var logodiv = $('<div></div>')
        			    .css("width", options.width+"px")
        			    .css("height", options.height+"px")
        			    .css("background", "url("+options.logo+") no-repeat center center")
        			    .css("position", "absolute")
        			    .css("z-index", "1");
        			    
        			    //��logo��������
        			    divcontainer.append(logodiv);
        			    //��table��������
        			    divcontainer.append($table);
        			    
        			    return divcontainer;
			}	
			return $table;
		}
  

		return this.each(function(){
			var element	= options.render == "canvas" ? createcanvas() : createtable();
			$(element).appendto(this);
		});
	};
})( jquery );

function utf16to8(str) { //ת�� 
    var out, i, len, c; 
    out = ""; 
    len = str.length; 
    for (i = 0; i < len; i++) { 
        c = str.charcodeat(i); 
        if ((c >= 0x0001) && (c <= 0x007f)) { 
            out += str.charat(i); 
        } else if (c > 0x07ff) { 
            out += string.fromcharcode(0xe0 | ((c >> 12) & 0x0f)); 
            out += string.fromcharcode(0x80 | ((c >> 6) & 0x3f)); 
            out += string.fromcharcode(0x80 | ((c >> 0) & 0x3f)); 
        } else { 
            out += string.fromcharcode(0xc0 | ((c >> 6) & 0x1f)); 
            out += string.fromcharcode(0x80 | ((c >> 0) & 0x3f)); 
        } 
    } 
    return out; 
}