(function($) {

  $.registerLiquidCanvasPlugin({
    name: "rect",
    paint: function(area) {
      area.ctx.beginPath();
      area.ctx.rect(0, 0, area.width, area.height);
      area.ctx.closePath();
      if (this.action) this.action.paint(area);  // for chaining
    }
  });
  
  $.registerLiquidCanvasPlugin({
    name: "roundedRect",
    defaultOpts: { radius:20 },
    paint: function(area) {
      var ctx = area.ctx;
      var opts = this.opts;
      ctx.beginPath();
      ctx.moveTo(0, opts.radius);
      ctx.lineTo(0, area.height - opts.radius);
      ctx.quadraticCurveTo(0, area.height, opts.radius, area.height);
      ctx.lineTo(area.width - opts.radius, area.height);
      ctx.quadraticCurveTo(area.width, area.height, area.width, area.height - opts.radius);
      ctx.lineTo(area.width, opts.radius);
      ctx.quadraticCurveTo(area.width, 0, area.width - opts.radius, 0);
      ctx.lineTo(opts.radius, 0);
      ctx.quadraticCurveTo(0, 0, 0, opts.radius);
      ctx.closePath();
      if (this.action) this.action.paint(area);  // for chaining
    },
    shrink: function(area, steps) {
      this.defaultShrink(area, steps);
      this.opts.radius -= steps;
    }
  });
  
  // This is a Liquid Canvas Plugin
  $.registerLiquidCanvasPlugin({
    name: "fill",
    defaultOpts: { color:"#aaa" },
    paint: function(area) {
      area.ctx.fillStyle = this.opts.color;
      this.action.paint(area);
      area.ctx.fill();
    }
  });

  $.registerLiquidCanvasPlugin({  // hmmmmmmm, no rotation? no width??? ah patterns!
    name: "image",
    defaultOpts: { url:"http://www.ruzee.com/files/liquid-canvas-image.png" },
    paint: function(area) {
      var image = new Image();
      image.src = this.opts.url;
      image.onload = function() { 
        area.ctx.drawImage(this, 0, 0); 
      };
    }
  });

  // This is a Liquid Canvas Plugin
  $.registerLiquidCanvasPlugin({
    name: "gradient",
    defaultOpts: { from: "#ffffff", to:"#666666" },
		/* from：グラデーションの開始色（上）　to：グラデーションの終了色（下） */
    paint: function(area) {
      var grad = area.ctx.createLinearGradient(0, 0, 0, area.height);
      grad.addColorStop(0, this.opts.from);
      grad.addColorStop(1, this.opts.to);
      area.ctx.fillStyle = grad;
      this.action.paint(area);
      area.ctx.fill();
    }
  });
  // End of Liquid Canvas Plugin
  
  $.registerLiquidCanvasPlugin({
    name: "shadow",
    defaultOpts: { width:3, color:'#000000', shift:2 },
		/* width：影の幅　color：影の色　shift：影の上下位置（＋で影が下に、−で影が上にずれて見えるようになる） */
    paint: function(area) {
      var sw = this.opts.width;
      area.ctx.fillStyle = this.opts.color; 
      area.ctx.globalAlpha = 1.0 / sw;
      for (var s = 0; s < sw; ++s) {
        this.action.paint(area);
        area.ctx.fill();
        this.action.shrink(area, 1);
      }
      area.ctx.globalAlpha = 1;
      area.ctx.translate(0, -this.opts.shift);
			/* 座標　0が横位置（＋で右に、−で左にずれて見えるようになる）、-this.opts.shiftはdefaultOptsで指定したshiftの値 */
    }
  });

  $.registerLiquidCanvasPlugin({
    name: "border",
    defaultOpts: { color:'#88ff44', width:3 },
		/* color：線の色　width：線の幅 */
    paint: function(area) {
      var bw = this.opts.width;
      area.ctx.strokeStyle = this.opts.color;
      area.ctx.lineWidth = bw;
      this.action.shrink(area, bw / 2);
      this.action.paint(area);
      area.ctx.stroke();
      this.action.shrink(area, bw / 2);
    }
  });
	
	$.registerLiquidCanvasPlugin({
		name: "mandala",
		paint: function(area) {
			var opts = this.opts;
			var ctx = area.ctx;
			var min = area.width > area.height ? area.height : area.width;
			var trans = min / 3;
			var rad = trans / 3;
			for (var i = 0; i < 10; ++i) {
				area.save();
				ctx.translate(area.width / 2, area.height / 2);
				ctx.rotate(i * 2*Math.PI / 10);
				ctx.translate(trans - rad, 0);
				area.width = 30;
				area.height = 30;
				this.action.paint(area);
				area.restore();
			}
		}
	});



})(jQuery);