Listing Harmony Hub activities in HABpanel

I am trying to build a HABpanel widget to control my Harmony Hub. I would like to have a dropdown with all the current activities and I have that working, but the list is hardcodet in the widget. I would like the list to be fetched directly from the hub itself.

I found out that the channel-types rest api provides the list I need, but now I need to fill this list into the widget.

I am trying to do at http config to hold the URL for the channel-type.

  "parameters": [],
  "parameterGroups": [],
  "description": "Current activity for HarmonyHub Harmony Hub",
  "label": "Current Activity",
  "itemType": "String",
  "kind": "STATE",
  "stateDescription": {
    "pattern": "%s",
    "readOnly": false,
    "options": [
        "value": "PowerOff",
        "label": "PowerOff"
        "value": "Watch TV",
        "label": "Watch TV"
        "value": "Play Xbox",
        "label": "Play Xbox"
  "tags": [],
  "UID": "harmonyhub:hub:HarmonyHub:currentActivity",
  "advanced": false

Then I have created an item that calls some js to pass the JSON and return a list.

String harmonyHubActivities "Harmony Hub activities [%s]" { http="<[harmonyHubActivities:60000:JS(getHarmonyHubActivities.js)]" }
(function(i) {
    var json = JSON.parse(i);
    return (json["stateDescription"]["options"]);

Right now the script return the full json. I would like to just get the options list. And then I would like to pass the list to the widget instead of the static list sceneMap.

<div ng-init="sceneMap={
              'PowerOff' : 'PowerOff',
              'Watch TV' : 'Watch TV',
              'Play Xbox' : 'Play Xbox',
             }" />

            <div style="width: 100%;" class="btn-group" uib-dropdown>
              <button id="single-button" type="button" class="action-button" uib-dropdown-toggle>
                <span id="hub-select">{{sceneMap[itemValue(config.hub)]}}</span><span class="caret" id="hue-controller-caret"></span>
                <span id="hub-select" ng-if="sceneMap[itemValue(config.hub)]== NULL">UNKNOWN ({{itemValue(config.hub)}})</span>
              <ul class="dropdown-menu" id="hub-controller-dropdown" uib-dropdown-menu role="menu" aria-labelledby="single-button">
                <li role="menuitem" ng-repeat="(state, label) in sceneMap">
                  <a ng-click="sendCmd(config.hub, state)">{{label}}</a>

I’m not that skilled in javascript and json parsing, so how do get the list from the json, and how do I get it into the widget?

And also I would like to know, if there is an easier way to get this list from the hub.