# All files / js hub.jsx

10.34% Statements 3/29
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     'use strict'

    class Hub {
      constructor () {
        this._subscriptions = {}
      }

      /* subscribes a callback to an event */
      subscribe (event, callback) {
        if (typeof event !== 'string') {
          event = event.getEventType()
        }

        let subs = this._subscriptions[event]
        if (subs === undefined) {
          this._subscriptions[event] = subs = []
        }

        for (let i = 0; i < subs.length; i++) {
          if (subs[i] === callback) {
            return false
          }
        }

        subs.push(callback)
        return true
      }

      /* unsubscribes a callback from an event */
      unsubscribe (event, callback) {
        if (typeof event !== 'string') {
          event = event.getEventType()
        }

        const subs = this._subscriptions[event]
        if (subs === undefined) {
          return false
        }

        for (let i = 0; i < subs.length; i++) {
          if (subs[i] === callback) {
            subs.splice(i, 1)
            return true
          }
        }
        return false
      }

      /* emits an event with some parameters */
      emit (event) {
        const subs = this._subscriptions[event.type]
        if (subs !== undefined) {
          subs.forEach((callback) => {
            try {
              callback(event)
            } catch (e) {
              console.log('Event callback failed: ', e, 'callback=',
                callback, 'event=', event)
            }
          })
        }
      }
    }

    const hub = new Hub()

    export default hub