function graphSettings(type) {
   var t;

   if (type == "arranged" || type == "chaotic") {
      t = {
         //id of the visualization container
         injectInto: 'infovis',
         //Enable zooming and panning
         //by scrolling and DnD
         Navigation: {
            enable: true,
            type: 'HTML',
            //Enable panning events only if we're dragging the empty
            //canvas (and not a node).
            panning: 'avoid nodes',
            zooming: 15 //zoom speed. higher is more sensible
         },
         // Change node and edge styles such as
         // color and width.
         // These properties are also set per node
         // with dollar prefixed data-properties in the
         // JSON structure.
         Node: {
            overridable: true,
            color: '#2D6A5D',
            type: 'customNode',
            dim: 25
         },
         Edge: {
            overridable: true,
            color: '#222222',
            type: 'customEdge',
            lineWidth: 2
         },
         //Native canvas text styling
         Label: {
            type: 'HTML', //Native or HTML
            size: 20,
            //style: 'bold'
         },
         //Add Tips
         Tips: {
            enable: false,
            onShow: function (tip, node) {}
         },
         // Add node events
         Events: {
            enable: true,
			enableForEdges: true,
            type: 'HTML',
            //Change cursor style when hovering a node
            onMouseEnter: function () {
               
            },
            onMouseLeave: function () {
               
            },
            //Update node positions when dragged
            onDragMove: function (node, eventInfo, e) {
			   clickDragOnTopic(node, eventInfo, e);
            },
			onDragEnd: function() {
				if (tempInit && tempNode2 == null) {
					$('#topic_addSynapse').val("true");
					$('#new_topic').fadeIn('fast');
					addMetacode();
					$('#topic_name').focus();
				}
				else if (tempInit && tempNode2 != null) {
					$('#topic_addSynapse').val("false");
					$('#synapse_topic1id').val(tempNode.id);
        			$('#synapse_topic2id').val(tempNode2.id);
					$('#new_synapse').fadeIn('fast');
					$('#synapse_desc').focus();
					tempNode = null;
					tempNode2 = null;
					tempInit = false;
				}
			},
			onDragCancel: function() {
				tempNode = null;
				tempNode2 = null;
				tempInit = false;
				$('#topic_addSynapse').val("false");
				$('#topic_topic1id').val(0);
				$('#topic_topic2id').val(0);
				Mconsole.plot();
			},
            //Implement the same handler for touchscreens
            onTouchMove: function (node, eventInfo, e) {
               $jit.util.event.stop(e); //stop default touchmove event
               this.onDragMove(node, eventInfo, e);
            },
            //Add also a click handler to nodes
            onClick: function (node, eventInfo, e) {
               //clicking on a node, or clicking on blank part of canvas?
               if (node.nodeFrom) {
					selectEdgeOnClickHandler(node);  
			   }
			   else if (node && !node.nodeFrom) {
                 selectNodeOnClickHandler(node);
               } else {
                 canvasDoubleClickHandler(eventInfo.getPos(), e);
               }//if
            }//onClick
         },
         //Number of iterations for the FD algorithm
         iterations: 200,
         //Edge length
         levelDistance: 200,
         // Add text to the labels. This method is only triggered
         // on label creation and only for DOM labels (not native canvas ones).
         onCreateLabel: function (domElement, node) {
           onCreateLabelHandler(domElement, node);
         },
         // Change node styles when DOM labels are placed
         // or moved.
         onPlaceLabel: function (domElement, node) {
            var style = domElement.style;
            var left = parseInt(style.left);
            var top = parseInt(style.top);
            var w = domElement.offsetWidth;
            style.left = (left - w / 2) + 'px';
            style.top = (top+25) + 'px';
            style.display = '';
         }
      };
   } else if (type = "centered") {
      t = {
         //id of the visualization container
         injectInto: 'infovis',
         //Optional: create a background canvas that plots  
         //concentric circles.  
         background: {
            CanvasStyles: {
               strokeStyle: '#333',
               lineWidth: 1.5
            }
         },
         //Enable zooming and panning
         //by scrolling and DnD
         Navigation: {
            enable: true,
            type: 'HTML',
            //Enable panning events only if we're dragging the empty
            //canvas (and not a node).
            panning: 'avoid nodes',
            zooming: 15 //zoom speed. higher is more sensible
         },
         // Change node and edge styles such as
         // color and width.
         // These properties are also set per node
         // with dollar prefixed data-properties in the
         // JSON structure.
         Node: {
            overridable: true,
            color: '#2D6A5D',
            type: 'customNode',
            dim: 25
         },
         Edge: {
            overridable: true,
            color: '#222222',
            type: 'customEdge',
            lineWidth: 2
         },
         //Native canvas text styling
         Label: {
            type: 'HTML', //Native or HTML
            size: 20,
            //style: 'bold'
         },
         //Add Tips
         Tips: {
            enable: false,
            onShow: function (tip, node) {}
         },
         // Add node events
         Events: {
            enable: true,
            type: 'HTML',
            //Change cursor style when hovering a node
            onMouseEnter: function () {
               
            },
            onMouseLeave: function () {
               
            },
            //Update node positions when dragged
            onDragMove: function (node, eventInfo, e) {
               clickDragOnTopic(node, eventInfo, e);
            },
			onDragEnd: function() {
				if (tempInit && tempNode2 == null) {
					$('#topic_addSynapse').val("true");
					$('#new_topic').fadeIn('fast');
					addMetacode();
					$('#topic_name').focus();
				}
				else if (tempInit && tempNode2 != null) {
					$('#topic_addSynapse').val("false");
					$('#synapse_topic1id').val(tempNode.id);
        			$('#synapse_topic2id').val(tempNode2.id);
					$('#new_synapse').fadeIn('fast');
					$('#synapse_desc').focus();
					tempNode = null;
					tempNode2 = null;
					tempInit = false;
				}
			},
			onDragCancel: function() {
				tempNode = null;
				tempNode2 = null;
				tempInit = false;
				Mconsole.plot();
			},
            //Implement the same handler for touchscreens
            onTouchMove: function (node, eventInfo, e) {
               $jit.util.event.stop(e); //stop default touchmove event
               this.onDragMove(node, eventInfo, e);
            },
			//Add also a click handler to nodes
            onClick: function (node, eventInfo, e) {
               //clicking on an edge, a node, or clicking on blank part of canvas?
               if (eventInfo.getEdge() != false || node.nodeFrom) {
					if (eventInfo.getEdge() != false) selectEdgeOnClickHandler(eventInfo.getEdge());
					else if (node.nodeFrom) selectEdgeOnClickHandler(node);  
			   }
			   else if (node && !node.nodeFrom) {
				 if (!Mconsole.busy) {
					selectNodeOnClickHandler(node);
					Mconsole.onClick(node.id, {  
					   hideLabels: false  
					});
				 }
               } 
			   else {
                 canvasDoubleClickHandler(eventInfo.getPos(), e);
               }//if
            }//onClick
         },
         //Number of iterations for the FD algorithm
         iterations: 200,
         //Edge length
         levelDistance: 200,
         // Add text to the labels. This method is only triggered
         // on label creation and only for DOM labels (not native canvas ones).
         onCreateLabel: function (domElement, node) {
           onCreateLabelHandler(domElement, node);
         },
         // Change node styles when DOM labels are placed
         // or moved.
         onPlaceLabel: function (domElement, node) {
            var style = domElement.style;
            var left = parseInt(style.left);
            var top = parseInt(style.top);
            var w = domElement.offsetWidth;
            style.left = (left - w / 2) + 'px';
            style.top = (top+25) + 'px';
            style.display = '';
         }
      };
   }

   return t;
}

// defining code to draw edges with arrows pointing in the middle of them
var renderMidArrow = function(from, to, dim, swap, canvas){ 
        var ctx = canvas.getCtx(); 
        // invert edge direction 
        if (swap) { 
              var tmp = from; 
              from = to; 
              to = tmp; 
        } 
        // vect represents a line from tip to tail of the arrow 
        var vect = new $jit.Complex(to.x - from.x, to.y - from.y); 
        // scale it 
        vect.$scale(dim / vect.norm()); 
        // compute the midpoint of the edge line 
        var midPoint = new $jit.Complex((to.x + from.x) / 2, (to.y + from.y) / 2); 
        // move midpoint by half the "length" of the arrow so the arrow is centered on the midpoint 
        midPoint.x += (vect.x / 0.7); 
        midPoint.y += (vect.y / 0.7); 
        // compute the tail intersection point with the edge line 
        var intermediatePoint = new $jit.Complex(midPoint.x - vect.x, 
midPoint.y - vect.y); 
        // vector perpendicular to vect 
        var normal = new $jit.Complex(-vect.y / 2, vect.x / 2); 
        var v1 = intermediatePoint.add(normal); 
        var v2 = intermediatePoint.$add(normal.$scale(-1)); 

        //ctx.strokeStyle = 'black';
        ctx.beginPath(); 
        ctx.moveTo(from.x, from.y); 
        ctx.lineTo(to.x, to.y); 
        ctx.stroke(); 
        ctx.beginPath(); 
        ctx.moveTo(v1.x, v1.y); 
        ctx.lineTo(midPoint.x, midPoint.y); 
        ctx.lineTo(v2.x, v2.y); 
        ctx.stroke(); 
};

// defining custom node type	
var nodeSettings = {
	  'customNode': {  
		  'render': function (node, canvas) {		  			  
			  var pos = node.pos.getc(true),
			  dim = node.getData('dim'),
			  cat = node.getData('metacode'),
			  inCommons = node.getData('inCommons'),
			  onCanvas = node.getData('onCanvas'),
			  ctx = canvas.getCtx();
			  
			  // if the topic is from the Commons draw a green circle around it
			  if (inCommons) {
				  ctx.beginPath();
				  ctx.arc(pos.x, pos.y, dim+3, 0, 2 * Math.PI, false);
				  ctx.strokeStyle = '#67be5f'; // green
				  ctx.lineWidth = 2;
				  ctx.stroke();
			  }
			  // if the topic is on the Canvas draw a white circle around it
			  if (onCanvas) {
				  ctx.beginPath();
				  ctx.arc(pos.x, pos.y, dim+3, 0, 2 * Math.PI, false);
				  ctx.strokeStyle = 'white';
				  ctx.lineWidth = 2;
				  ctx.stroke();
			  }
			  ctx.drawImage(imgArray[cat], pos.x - dim, pos.y - dim, dim*2, dim*2);

		  },
		  'contains': function(node, pos) {
			var npos = node.pos.getc(true), 
			dim = node.getData('dim');
			return this.nodeHelper.circle.contains(npos, pos, dim);
		  }
	  }
  }
  
  
// defining custom edges
 var edgeSettings = {  
	  'customEdge': {  
		'render': function(adj, canvas) {  
		  //get nodes cartesian coordinates 
		  var pos = adj.nodeFrom.pos.getc(true); 
		  var posChild = adj.nodeTo.pos.getc(true);
		  
		  var directionCat = adj.getData("category");
		  //label placement on edges 
		  //plot arrow edge 
		  if (directionCat == "none") {
				this.edgeHelper.line.render({ x: pos.x, y: pos.y }, { x: posChild.x, y: posChild.y }, canvas);
		  }
		  else if (directionCat == "both") {
				renderMidArrow({ x: pos.x, y: pos.y }, { x: posChild.x, y: posChild.y }, 13, true, canvas);
				renderMidArrow({ x: pos.x, y: pos.y }, { x: posChild.x, y: posChild.y }, 13, false, canvas);
		  }
		  else if (directionCat == "from-to") {
				var direction = adj.data.$direction;
				var inv = (direction && direction.length>1 && direction[0] != adj.nodeFrom.id);
				renderMidArrow({ x: pos.x, y: pos.y }, { x: posChild.x, y: posChild.y }, 13, inv, canvas);
		  }
		   
		  //check for edge label in data  
		  var desc = adj.getData("desc") + ' (' + adj.getData("id") + ')';
		  var showDesc = adj.getData("showDesc");
		  if( desc != "" && showDesc ) { 
			 //now adjust the label placement 
			var radius = canvas.getSize(); 
			var x = parseInt((pos.x + posChild.x - (desc.length * 5)) /2); 
			var y = parseInt((pos.y + posChild.y) /2); 
			canvas.getCtx().fillStyle = '#000';
			canvas.getCtx().font = 'bold 14px arial';
			canvas.getCtx().fillText(desc, x, y); 
		  }
		}, 'contains' : function(adj, pos) { 
				var from = adj.nodeFrom.pos.getc(true), 
				 to = adj.nodeTo.pos.getc(true);
				return this.edgeHelper.line.contains(from, to, pos, adj.Edge.epsilon); 
		}  
	  }  
	}
	
function selectEdgeOnClickHandler(adj) {
      var showDesc = adj.getData("showDesc");
	  if (showDesc) {
		adj.setData('showDesc', false, 'current');
	  	Mconsole.plot();  
	  } else if (!showDesc) {
	  	adj.setData('showDesc', true, 'current');
	  	Mconsole.plot();
	  }
}//selectEdgeOnClickHandler

function selectNodeOnClickHandler(node) {
   
    $('.showcard').css('display','none');
	$('.name').css('display','block');
	$('.name.topic_' + node.id).css('display','none');
	$('.showcard.topic_' + node.id).fadeIn('fast');
				
   //set final styles  
   Mconsole.graph.eachNode(function (n) {
      if (n.id != node.id) delete n.selected;
      n.setData('dim', 25, 'current');
      n.eachAdjacency(function (adj) {
         adj.setDataset('end', {
            lineWidth: 2,
            color: '#222222'
         });
         adj.setData('showDesc', false, 'current');
      });
   });
   if (!node.selected) {
      node.selected = true;
	  node.setData('dim', 1, 'current');  

      node.eachAdjacency(function (adj) {
         adj.setDataset('end', {
            lineWidth: 4,
            color: '#FFF'
         });
         adj.setData('showDesc', true, 'current');
      });
   } else {
	  node.setData('dim', 25, 'current');
      delete node.selected;
   }
   //trigger animation to final styles  
   Mconsole.fx.animate({
      modes: ['edge-property:lineWidth:color'],
      duration: 500
   });
}//selectNodeOnClickHandler

//for the canvasDoubleClickHandler function
var canvasDoubleClickHandlerObject = new Object();
canvasDoubleClickHandlerObject.storedTime = 0;

function canvasDoubleClickHandler(canvasLoc,e) {
   var TOLERANCE = 300; //0.3 seconds

   //grab the location and timestamp of the click
   var storedTime = canvasDoubleClickHandlerObject.storedTime;
   var now = Date.now(); //not compatible with IE8 FYI

   if (now - storedTime < TOLERANCE) {
      //pop up node creation :)
	  $('#topic_grabTopic').val("null");
	  $('#topic_addSynapse').val("false");
      document.getElementById('new_topic').style.left = e.x + "px";
      document.getElementById('new_topic').style.top = e.y + "px";
      $('#topic_x').val(canvasLoc.x);
      $('#topic_y').val(canvasLoc.y);
      $('#new_topic').fadeIn('fast');
	  addMetacode();
      $('#topic_name').focus();
   } else {
      canvasDoubleClickHandlerObject.storedTime = now;
	  $('#new_topic').fadeOut('fast');
	  $('#new_synapse').fadeOut('fast');
	  tempInit = false;
	  tempNode = null;
	  tempNode2 = null;
	  Mconsole.plot();
   }
}//canvasDoubleClickHandler

// ForceDirected Mode: for the creation of new topics and synapses through clicking and draggin with right clicks off of topics
function clickDragOnTopic(node, eventInfo, e) {
    if (node && !node.nodeFrom) {
	   $('#new_synapse').fadeOut('fast');
	   $('#new_topic').fadeOut('fast');
	   var pos = eventInfo.getPos();
	   // if it's a left click, move the node
	   if (e.button == 0 && !e.altKey ) {
		   node.pos.setc(pos.x, pos.y);
		   Mconsole.plot();
	   }
	   // if it's a right click, start synapse creation
	   else if (e.button == 2 || (e.button == 0 && e.altKey)) {
		   if (tempInit == false) {
			  tempNode = node;
			  tempInit = true;   
		   }
		   // 
		   temp = eventInfo.getNode();
		   if (temp != false && temp.id != node.id) { // this means a Node has been returned
			  tempNode2 = temp;
			  Mconsole.plot();
			  renderMidArrow({ x: tempNode.pos.getc().x, y: tempNode.pos.getc().y }, { x: temp.pos.getc().x, y: temp.pos.getc().y }, 13, false, Mconsole.canvas);
			  // before making the highlighted one bigger, make sure all the others are regular size
			  Mconsole.graph.eachNode(function (n) {
				  n.setData('dim', 25, 'current');
			  });
			  temp.setData('dim',35,'current');
			  Mconsole.fx.plotNode(tempNode, Mconsole.canvas);
			  Mconsole.fx.plotNode(temp, Mconsole.canvas);
		   } else if (!temp) {
			   tempNode2 = null;
			   Mconsole.graph.eachNode(function (n) {
				  n.setData('dim', 25, 'current');
			   });
			   //pop up node creation :)
			  $('#topic_grabTopic').val("null");
			  var myX = e.x - 110;
			  var myY = e.y - 30;
			  document.getElementById('new_topic').style.left = myX + "px";
			  document.getElementById('new_topic').style.top = myY + "px";
			  document.getElementById('new_synapse').style.left = myX + "px";
			  document.getElementById('new_synapse').style.top = myY + "px";
			  $('#topic_x').val(eventInfo.getPos().x);
			  $('#topic_y').val(eventInfo.getPos().y);
			  Mconsole.plot();
			  renderMidArrow({ x: tempNode.pos.getc().x, y: tempNode.pos.getc().y }, { x: pos.x, y: pos.y }, 13, false, Mconsole.canvas);
			  Mconsole.fx.plotNode(tempNode, Mconsole.canvas);
		   }
	   }
   }	
}

function onCreateLabelHandler(domElement, node) {
  var html = '                                                                \
    <div class="CardOnGraph"                                                  \
         title="Click to Hide"                                                \
         id="topic_$_id_$">                                                   \
      <p class="type best_in_place"                                           \
         id="best_in_place_metacode"                                          \
         data-url="/topics/$_id_$"                                            \
         data-object="topic"                                                  \
         data-collection=$_metacode_choices_$                                 \
         data-attribute="metacode"                                            \
         data-type="select">$_metacode_$</p>                                  \
      <a href="/topics/$_id_$">                                               \
        <img alt="$_metacode_$"                                               \
             class="icon"                                                     \
             height="50"                                                      \
             width="50"                                                       \
           src="$_imgsrc_$" />                                                \
      </a>                                                                    \
      <div class="scroll">                                                    \
        <span class="title best_in_place"                                     \
              id="best_in_place_name"                                         \
              data-url="/topics/$_id_$"                                       \
              data-object="topic"                                             \
              data-attribute="name"                                           \
              data-type="input">$_name_$</span>                               \
        <div class="contributor">                                             \
          Added by: <a href="/users/$_userid_$">$_username_$</a>              \
        </div>                                                                \
        <div class="desc">                                                    \
          <p>$_desc_$</p>                                                     \
        </div>                                                                \
      </div>                                                                  \
      <a href="$_link_$" class="link" target="_blank">$_link_$</a>            \
    </div>';

  //create metacode_choices array from imgArray
  var metacode_choices = "'[";
  for (var key in imgArray) {
    if (imgArray.hasOwnProperty(key)) {
      metacode_choices += '["' + key + '","' + key + '"],';
    }
  }
  //remove trailing comma and add ]
  metacode_choices = metacode_choices.slice(0, -1); 
  metacode_choices += "]'";

  html = html.replace(/\$_id_\$/g, node.id);
  html = html.replace(/\$_metacode_\$/g, node.getData("metacode"));
  html = html.replace(/\$_imgsrc_\$/g, imgArray[node.getData("metacode")].src);
  html = html.replace(/\$_name_\$/g, node.name);
  html = html.replace(/\$_userid_\$/g, node.getData("userid"));
  html = html.replace(/\$_username_\$/g, node.getData("username"));
  html = html.replace(/\$_desc_\$/g, node.getData("desc"));
  html = html.replace(/\$_link_\$/g, node.getData("link"));
  html = html.replace(/\$_metacode_choices_\$/g, metacode_choices);

  var showCard = document.createElement('div');
  showCard.className = 'showcard topic_' + node.id;
  showCard.innerHTML = html;
  showCard.style.display = "none";
  domElement.appendChild(showCard);

  // add some events to the label
  showCard.onclick = function(){
    delete node.selected;
    node.setData('dim', 25, 'current');
    node.eachAdjacency(function (adj) {
      adj.setDataset('end', {
        lineWidth: 2,
        color: '#222222'
      });
      adj.setData('showDesc', false, 'current');
    });
    Mconsole.fx.animate({
      modes: ['edge-property:lineWidth:color'],
      duration: 500
    });
//    $('.showcard.topic_' + node.id).fadeOut('fast', function(){
//      $('.name').css('display','block');
//      Mconsole.plot();
//    });
  }

  // Create a 'name' button and add it to the main node label
  var nameContainer = document.createElement('span'),
    style = nameContainer.style;
  nameContainer.className = 'name topic_' + node.id;
  nameContainer.innerHTML = '<div class="label">' + node.name + '</div>';
  domElement.appendChild(nameContainer);
  style.fontSize = "0.9em";
  style.color = "#222222";

  // add some events to the label
  nameContainer.onclick = function(){
    selectNodeOnClickHandler(node)
  }
}//onCreateLabelHandler