var w = 960,

    h = 500,

    fill = d3.scale.ordinal().range(colorbrewer.Greys[9].slice(1, 4)),

    stroke = d3.scale.linear().domain([0, 1e4]).range(["brown", "steelblue"]);

var treemap = d3.layout.treemap()

    .size([w, h])

    .value(function(d) { return d.size; });

var bundle = d3.layout.bundle();

var div = d3.select("#chart").append("div")

    .style("position", "relative")

    .style("width", w + "px")

    .style("height", h + "px");

var line = d3.svg.line()

    .interpolate("bundle")

    .tension(.85)

    .x(function(d) { return d.x + d.dx / 2; })

    .y(function(d) { return d.y + d.dy / 2; });

d3.json("../data/flare-imports.json", function(classes) {

  var nodes = treemap.nodes(packages.root(classes)),

      links = packages.imports(nodes);

  div.selectAll("div")

      .data(nodes)

    .enter().append("div")

      .attr("class", "cell")

      .style("background", function(d) { return d.children ? fill(d.key) : null; })

      .call(cell)

      .text(function(d) { return d.children ? null : d.key; });

  div.append("svg:svg")

      .attr("width", w)

      .attr("height", h)

      .style("position", "absolute")

    .selectAll("path.link")

      .data(bundle(links))

    .enter().append("svg:path")

      .style("stroke", function(d) { return stroke(d[0].value); })

      .attr("class", "link")

      .attr("d", line);

});

function cell() {

  this

      .style("left", function(d) { return d.x + "px"; })

      .style("top", function(d) { return d.y + "px"; })

      .style("width", function(d) { return d.dx - 1 + "px"; })

      .style("height", function(d) { return d.dy - 1 + "px"; });

}