text: /* ------------------------------------------------------------------------------
   *
   *  # D3.js - collapsible tree layout
   *
   *  Demo of tree layout setup with collapsible nodes
   *
   * ---------------------------------------------------------------------------- */
  
  
  // Setup module
  // ------------------------------
  
  var D3TreeCollapsible = function() {
  
  
      //
      // Setup module components
      //
  
      // Chart
      var _treeCollapsible = function() {
          if (typeof d3 == 'undefined') {
              console.warn('Warning - d3.min.js is not loaded.');
              return;
          }
  
          // Main variables
          var element = document.getElementById('d3-tree-collapsible'),
              height = 800;
  
  
          // Initialize chart only if element exsists in the DOM
          if(element) {
  
              // Basic setup
              // ------------------------------
  
              // Define main variables
              var d3Container = d3.select(element),
                  margin = {top: 0, right: 0, bottom: 0, left: 40},
                  width = d3Container.node().getBoundingClientRect().width - margin.left - margin.right,
                  height = height - margin.top - margin.bottom - 5,
                  i = 0,
                  root;
  
  
  
              // Create chart
              // ------------------------------
  
              // Add SVG element
              var container = d3Container.append("svg");
  
              // Add SVG group
              var svg = container
                  .attr("width", width + margin.left + margin.right)
                  .attr("height", height + margin.top + margin.bottom)
                  .append("g")
                      .attr("transform", "translate(" + margin.left + "," + margin.top + ")");
  
  
  
              // Construct chart layout
              // ------------------------------
  
              // Tree
              var tree = d3.layout.tree()
                  .size([height, width - 180]);
  
              // Diagonal projection
              var diagonal = d3.svg.diagonal()
                  .projection(function(d) { return [d.y, d.x]; });
  
  
  
              // Load data
              // ------------------------------
  
              d3.json(" global_assets/demo_data/d3/tree/tree_data_collapsible.json", function(error, json) {
  
                  root = json;
                  root.x0 = height/2;
                  root.y0 = 0;
  
                  // Toggle nodes function
                  function toggleAll(d) {
                      if (d.children) {
                          d.children.forEach(toggleAll);
                          toggle(d);
                      }
                  }
  
                  // Initialize the display to show a few nodes
                  root.children.forEach(toggleAll);
                  toggle(root.children[1]);
                  toggle(root.children[1].children[2]);
                  toggle(root.children[9]);
                  toggle(root.children[9].children[0]);
  
                  update(root);
              });
  
  
  
              // Layout setup
              // ------------------------------
  
              // Update nodes
              function update(source) {
  
                  // Set duration
                  var duration = d3.event && d3.event.altKey ? 5000 : 500;
  
                  // Compute the new tree layout.
                  var nodes = tree.nodes(root).reverse();
  
                  // Normalize for fixed-depth.
                  //nodes.forEach(function(d) { d.y = d.depth * 250; });
  
                  // Update the nodes…
                  var node = svg.selectAll(".d3-tree-node")
                      .data(nodes, function(d) { return d.id || (d.id = ++i); });
  
  
                  // Enter nodes
                  // ------------------------------
  
                  // Enter any new nodes at the parent's previous position.
                  var nodeEnter = node.enter().append("g")
                      .attr("class", "d3-tree-node")
                      .attr("transform", function(d) { return "translate(" + source.y0 + "," + source.x0 + ")"; })
                      .on("click", function(d) { toggle(d); update(d); });
  
                  // Add node circles
                  nodeEnter.append("circle")
                      .attr("r", 1e-6)
                      .style("fill", "#fff")
                      .style("stroke", "#2196F3")
                      .style("stroke-width", 1.5)
                      .style("cursor", "pointer")
                      .style("fill", function(d) { return d._children ? "#2196F3" : "#fff"; });
  
                  // Add nodes text
                  nodeEnter.append("text")
                      .attr("x", function(d) { return d.children || d._children ? -10 : 10; })
                      .attr("dy", ".35em")
                      .style("text-anchor", function(d) { return d.children || d._children ? "end" : "start"; })
                      .style("font-size", 12)
                      .style("fill-opacity", 1e-6)
                      .text(function(d) { return d.name; });
  
  
                  // Update nodes
                  // ------------------------------
  
                  // Transition nodes to their new position.
                  var nodeUpdate = node.transition()
                      .duration(duration)
                      .attr("transform", function(d) { return "translate(" + d.y + "," + d.x + ")"; });
  
                  // Update circle
                  nodeUpdate.select("circle")
                      .attr("r", 4.5)
                      .style("fill", function(d) { return d._children ? "#2196F3" : "#fff"; });
  
                  // Update text
                  nodeUpdate.select("text")
                      .style("fill-opacity", 1);
  
  
                  // Exit nodes
                  // ------------------------------
  
                  // Transition exiting nodes to the parent's new position.
                  var nodeExit = node.exit()
                      .transition()
                          .duration(duration)
                          .attr("transform", function(d) { return "translate(" + source.y + "," + source.x + ")"; })
                          .remove();
  
                  // Update circles
                  nodeExit.select("circle")
                      .attr("r", 1e-6);
  
                  // Update text
                  nodeExit.select("text")
                      .style("fill-opacity", 1e-6);
  
  
                  // Links
                  // ------------------------------
  
                  // Update the links…
                  var link = svg.selectAll(".d3-tree-link")
                      .data(tree.links(nodes), function(d) { return d.target.id; });
  
                  // Enter any new links at the parent's previous position.
                  link.enter().insert("path", "g")
                      .attr("class", "d3-tree-link")
                      .style("fill", "none")
                      .style("stroke", "#ddd")
                      .style("stroke-width", 1.5)
                      .attr("d", function(d) {
                          var o = {x: source.x0, y: source.y0};
                          return diagonal({source: o, target: o});
                      })
                      .transition()
                          .duration(duration)
                          .attr("d", diagonal);
  
                  // Transition links to their new position.
                  link.transition()
                      .duration(duration)
                      .attr("d", diagonal);
  
                  // Transition exiting nodes to the parent's new position.
                  link.exit().transition()
                      .duration(duration)
                      .attr("d", function(d) {
                      var o = {x: source.x, y: source.y};
                          return diagonal({source: o, target: o});
                      })
                      .remove();
  
                  // Stash the old positions for transition.
                  nodes.forEach(function(d) {
                      d.x0 = d.x;
                      d.y0 = d.y;
                  });
  
  
                  // Resize chart
                  // ------------------------------
  
                  // Call function on window resize
                  $(window).on('resize', resize);
  
                  // Call function on sidebar width change
                  $('.sidebar-control, .d3-tree-node circle').on('click', resize);
  
  
                  // Resize function
                  // 
                  // Since D3 doesn't support SVG resize by default,
                  // we need to manually specify parts of the graph that need to 
                  // be updated on window resize
                  function resize() {
  
                      // Layout variables
                      width = d3Container.node().getBoundingClientRect().width - margin.left - margin.right,
                      nodes = tree.nodes(root),
                      links = tree.links(nodes);
  
                      // Layout
                      // -------------------------
  
                      // Main svg width
                      container.attr("width", width + margin.left + margin.right);
  
                      // Width of appended group
                      svg.attr("width", width + margin.left + margin.right);
  
  
                      // Tree size
                      tree.size([height, width - 180]);
  
                      diagonal.projection(function(d) { return [d.y, d.x]; });
  
  
                      // Chart elements
                      // -------------------------
  
                      // Link paths
                      svg.selectAll(".d3-tree-link").attr("d", diagonal)
  
                      // Node paths
                      svg.selectAll(".d3-tree-node").attr("transform", function(d) { return "translate(" + d.y + "," + d.x + ")"; });
                  }
              }
  
              // Toggle childrens
              function toggle(d) {
                  if (d.children) {
                      d._children = d.children;
                      d.children = null;
                  }
                  else {
                      d.children = d._children;
                      d._children = null;
                  }
              }
          }
      };
  
  
      //
      // Return objects assigned to module
      //
  
      return {
          init: function() {
              _treeCollapsible();
          }
      }
  }();
  
  
  // Initialize module
  // ------------------------------
  
  document.addEventListener('DOMContentLoaded', function() {
      D3TreeCollapsible.init();
  });
  