(function () {
  Polymer({
    is: 'fm-private-storex',
    properties: {
      /**
       * @description Store all states
       */
      store: {
        type: Object,
        value: function () {
          return {};
        }
      },
      /**
       * @description Array with callbacks functions subscribers
       */
      subscriptions: {
        type: Array,
        value: function () {
          return [];
        }
      },
      /**
       * @description Mutations saved to apply
       */
      mutations: {
        type: Object,
        value: function () {
          return [];
        },
        observer: 'onUpdateMutations'
      }
    },
    /**
     * @description Observers to apply changes on store
     */
    observers: ['onUpdate(store.*)'],
    /**
     * @description In attached generates all init object
     */
    attached: function () {
      /**
       * @description Object on window to get a bridge communication
       * @type {{subscribe, commit, mutations: *}}
       */
      window.gs = window.gs || {
        subscribe: this.subscribe.bind(this),
        commit: this.commit.bind(this),
        mutations: this.mutations
      }
      /**
       * @description Proxy to protect the bridge store
       * @type {Proxy}
       */
      var pgs = new Proxy(window.gs, {
        set: function (obj, prop, value) {
          if (prop === 'commit') {
            throw new TypeError('"commit" option cannot be modified');
          } else if (prop === 'mutations') {
            if (typeof value !== 'object') {
              throw new TypeError('"mutations" option should be an object');
            }
          } else if (prop === 'subscribe') {
            if (typeof value !== 'function') {
              throw new TypeError('"subscribe" option should be a function');
            }
          } else {
            throw new TypeError('The only valid options are "commit", "subscriptions" and "mutations"');
          }
          Reflect.set(obj, prop, value);
        },
        deleteProperty: function(target, prop) {
          throw new Error('This object cannot be deleted')
        }
      })
      window.gs = pgs;
    },
    /**
     * @description Function to subscribe the callbacks fn
     * @param fn
     * @returns {function(this:subscribe)}
     */
    subscribe: function (fn) {
      this.subscriptions.push(fn);
      return function () {
        var idx = this.subscriptions.indexOf(fn)
        if (idx > -1) {
          this.subscriptions.splice(idx, 1);
        }
      }.bind(this)
    },
    /**
     * @description Function to apply the mutations
     * @param mutation
     * @param value
     */
    commit: function (mutation, value) {
      this.set('mutations', gs.mutations);
      if (this.mutations[mutation]) {
        (this.mutations[mutation])(this, value);
      } else {
        throw new Error('The mutation ' + mutation + ' does not exist.');
      }

    },
    /**
     * @description Function that execute each fn from subscribers
     * @param store
     */
    onUpdate: function (store) {
      if (this.subscriptions) {
        this.subscriptions.forEach(function (t) {
          t(store);
        })
      }
    },
    onUpdateMutations: function (mutation) {
      console.log(mutation);
    }
  })
})()