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var canvas = $("canvas");
var color = $(".selected").css("background-color");
var context = $canvas[0].getContext("2d");
var lastEvent;
var mouseDown = false;

//When clicking on control list items
$(".controls").on("click", "li", function(){
  //Deselect siblings elements
  $(this).siblings().removeClass("selected");
  //Select clicked element
  $(this).addClass("selected");
  //cache color
  color = $(this).css("background-color");
});


//When "new color" is pressed
$("#revealColorSelect").click(function(){
  //show or hide colorSelect
  changeColor();
  $("#colorSelect").toggle();
});

 //update the newColor span
function changeColor() {
  var r = $("#red").val();
  var g = $("#green").val();
  var b = $("#blue").val();
  $("#newColor").css("background-color", "rgb(" + r + "," + g + "," + b + ")");
}

//When color sliders change
$("input[type=range]").change(changeColor);

//When "add color" is pressed
$("#addNewColor").click(function(){
 //append the color to the controls ul
  var $newColor = $("<li></li>")
  $newColor.css("background-color",$("#newColor").css("background-color"));
  $(".controls ul").append($newColor);
  //Select the new color
  $newColor.click();
});

//On mouse events on the canvas
$canvas.mousedown(function(e){
  lastEvent = e;
  mouseDown = true;
}).mousemove(function(e){
  //Draw lines
if(mouseDown){
  context.beginPath();
  context.moveTo(lastEvent.offsetx, lastEvent.offsety);
  context.lineTo(e.offsetx,e.offsety);
  context.strokeStyle = color;
  context.stroke();
  lastEvent = e;
  }
}).mouseup(function(){
  mouseDown = false;
}).mouseleave(function(){
  $canvas.mouseup();
});