// JS

var chart = JSC.chart("chartDiv", {
  title_label_text: "Select points",
  debug: true,
  type: "column",
  events_pointSelectionChanged: function syncAllCheckbox() {
     //If all points are selected or cleared, this syncs the checkAll checkbox.
    var chart = this;
    var allPoints = chart.series().points().items.length;
    var selectedPoints = chart.series().points(function (p) {
      return p.options("selected");
    }).items.length;

    //If selected point count equals all points count or if no points are selected.
    if (selectedPoints === allPoints || !selectedPoints) {
      chart
        .legends(0)
        .entries("checkAll")
        .options({ checkbox_checked: !!selectedPoints });
    }
  },
  legend: {
    defaultEntry: {
      // Enable checkboxes for each point legend entry.
      checkbox_enabled: true,
      hoverAction: "none"
    },
    customEntries: [
      {
        id: "checkAll",
        // Position as first entry.
        sortOrder: -1,
        // Enable checkbox. Required since custom entries don't have them by default.
        checkbox_enabled: true,
        // Appearance
        value: "Value",
        name: "Name",
        icon: "none",
        style_fontWeight: "bold",
        // Apply checked state to all points.
        events_click: function () {
          var checked = this.options("checkbox.checked");
          this.chart.series().points().options({ selected: checked });
        }
      }
    ]
  },
  defaultSeries: {
    palette: "default",
    pointSelection: "multiple",
    firstPoint_legendEntry_lineAbove: true
  },

  yAxis_label_text: "Units Sold",
  xAxis_label_text: "Quarter",
  series: [
    {
      name: "A",
      points: [
        { x: "Q1", y: 230 },
        { x: "Q2", y: 240 },
        { x: "Q3", y: 267 },
        { x: "Q4", y: 238 }
      ]
    }
  ]
});