//noprotect

var width = 960,
    height = 500;

var color = d3.scale.category20();

var force = d3.layout.force()
    .linkDistance(1000)
    .size([width, height]);

var svg = d3.select("body").append("svg")
    .attr("width", width)
    .attr("height", height)

var zoomable_layer = svg.append('g');

zoom = d3.behavior.zoom()
  .scaleExtent([0.5,4])
  .on('zoom', function() {
    zoomable_layer
      .attr('transform', "translate(" + zoom.translate() + ")scale(" + zoom.scale() + ")");
  });

svg.call(zoom);

d3.json("node_link_ontology.json", function(error, graph) {
   
  var thickness = d3.scale.sqrt()
      .domain([1, d3.max(graph.links, function(d) {return d.value;})])
      .range([0.1, 10]);
  
  nodeLabelID = [];
  graph.nodes.forEach(function(d) {    
    nodeLabelID[d.id] = d.name;
  });
  
  force
      .nodes(graph.nodes)
      .links(graph.links)
      .start();

  var link = zoomable_layer.selectAll(".link")
      .data(graph.links)
    .enter().append("line")
      .attr("class", "link")
      .style("stroke-width", function(d) { return thickness(d.value); });
  
  link.append("title")
    .text(function(d) {
      return nodeLabelID[d.source.id] + " -> " + nodeLabelID[d.target.id]; 
    });

  var node = zoomable_layer.selectAll(".node")
      .data(graph.nodes)
    .enter().append("circle")
      .attr("class", "node")
      .attr("r", 2.5)
      .style("fill", function(d) { return color(d.group); })
      .call(force.drag);

  node.append("title")
      .text(function(d) { return d.name; });

  force.on("tick", function() {
    link.attr("x1", function(d) { return d.source.x; })
        .attr("y1", function(d) { return d.source.y; })
        .attr("x2", function(d) { return d.target.x; })
        .attr("y2", function(d) { return d.target.y; });

    node.attr("cx", function(d) { return d.x; })
        .attr("cy", function(d) { return d.y; });
  });
});