bq/composr-core

'use strict'

var events = require('events')
var eventEmitter = new events.EventEmitter()
eventEmitter.setMaxListeners(100)

var _ = require('lodash')
var suscribed = {}

function on (fnNames, originModule, fn, errCb) {
  fnNames = !_.isArray(fnNames) ? [fnNames] : fnNames

  var genericErrorCallback = function genericErrorCallback (err) {
    console.log('Error on module ' + originModule + ', ' + fnNames.join(',') + err)
  }

  errCb = errCb || genericErrorCallback

  fnNames.forEach(function (fnName) {
    // Avoid various suscriptions with the same origin
    if (!suscribed[fnName]) {
      suscribed[fnName] = {}
    } else if (suscribed[fnName][originModule]) {
      eventEmitter.removeListener(fnName, suscribed[fnName][originModule].fn)
      eventEmitter.removeListener('error' + fnName, suscribed[fnName][originModule].errCb)
    }

    suscribed[fnName][originModule] = {
      fn: fn,
      errCb: errCb
    }

    eventEmitter.on(fnName, fn)
    eventEmitter.on('error' + fnName, errCb)
  })
}

function resetSuscriptions () {
  _.forIn(suscribed, function (itemValue, fnName) {
    _.forIn(itemValue, function (opts) {
      eventEmitter.removeListener(fnName, opts.fn)
      eventEmitter.removeListener(fnName, opts.errCb)
    })
  })
}

function emit () {
  eventEmitter.emit.apply(eventEmitter, Array.prototype.slice.call(arguments))
}

module.exports = {
  on: on,
  emit: emit,
  resetSuscriptions: resetSuscriptions,
  emitter: eventEmitter
}