fm

gistfile1.txt

const fm = (() => {
  const model = {}
  let observers = { fm_observe_all : [] }
  function sub (key, observerCallback) {
    if (typeof observers[key] === 'undefined') {
      observers[key] = []
    }
    if (!observers[key].includes(observerCallback)) {
      observers[key].push(observerCallback)
    }
  }
  function unsub (key, observerCallback) {
    var index = observers[key].indexOf(observerCallback)
    if (index > -1) {
      observers[key].splice(index, 1)
    }
  }
  function emit (key) {
    if (typeof observers[key] !== 'undefined') {
      observers[key].forEach((observerCallback) => {
        observerCallback(model[key])
      })
    }
    observers['fm_observe_all'].forEach((observerCallback) => {
      observerCallback({[key]: model[key]})
    })
  }
  function save (key, val) {
    model[key] = val
    emit(key)
  }
  function silentSave (key, val) {
    model[key] = val
  }
  function val (key) {
    return model[key]
  }
  return {
    sub,
    unsub,
    emit,
    save,
    silentSave,
    val
  }
})()
export default fm;