elliptical-observe/lib-es/store.js

Sideways Data Loading for Elliptical

import _typeof from 'babel-runtime/helpers/typeof';
import _ from 'lodash';
import Observable from 'zen-observable';

export default function createStore() {
  var items = [];
  var observer = void 0;
  var data = new Observable(function (newObserver) {
    observer = newObserver;
  });

  function register(element) {
    var existing = _.find(items, function (item) {
      return _.isEqual(element, item.element);
    });

    if (existing) {
      return existing.value;
    } else {
      var _ret = function () {
        var newItem = { element: element };
        items.push(newItem);

        var fetched = element.type.fetch(element);

        var subscription = fetched.subscribe({
          next: function next(value) {
            newItem.value = value;

            if (observer) {
              observer.next({ element: element, value: value });
            }
          }
        });
        newItem.subscription = subscription;

        return {
          v: newItem.value
        };
      }();

      if ((typeof _ret === 'undefined' ? 'undefined' : _typeof(_ret)) === "object") return _ret.v;
    }
  }

  function remove(item) {
    var index = items.indexOf(item);
    var removed = items.splice(index, 1);
    removed[0].subscription.unsubscribe();
  }

  return { data: data, register: register, items: items, remove: remove };
}