var width = 400,
    height = 400,
    radius = Math.min(width, height) / 2;

var hist = window.histograms.states;

var total = d3.sum(hist,function(d) { return d.hits });

var desc = d3.select('#desc');

desc.text('Total: '+total);

var color = d3.scale.ordinal()
    .range(["#98abc5", "#8a89a6", "#7b6888", "#6b486b", "#a05d56", "#d0743c", "#ff8c00"]);

var arc = d3.svg.arc()
    .outerRadius(radius)
    .innerRadius(radius / 4);

var pie = d3.layout.pie()
    .sort(null)
    .value(function(d) { return d.hits; });

var svg = d3.select("#chart-div").append("svg")
    .attr("width", width)
    .attr("height", height)
  .append("g")
    .attr("transform", "translate(" + width / 2 + "," + height / 2 + ")");

  var g = svg.selectAll(".arc")
      .data(pie(hist))
    .enter().append("g")
      .attr("class", "arc");

  g.append("path")
      .attr("d", arc)
      .style("fill", function(d) { return color(d.data.hits); })
      .on("mouseover",function(d) {desc.text(d.data.name+': '+d.data.hits);})
      .on("mouseout",function(d) {desc.text('Total: '+total);});

  g.append("text")
      .attr("transform", function(d) { return "translate(" + arc.centroid(d) + ")"; })
      .attr("dy", ".35em")
      .style("text-anchor", "middle")
      .text(function(d) {return d.data.name});