progress tracker

index.js

"use strict"
var EventEmitter = require("events").EventEmitter
var util = require("util")

var Tracker = exports.Tracker = function (done,todo) {
  this.workDone = done || 0
  this.workTodo = todo || 0
}
util.extend(Tracker, EventEmitter)

Tracker.prototype.completed = function () {
  return this.workTodo==0 ? 0 : this.workDone / this.workTodo
}

Tracker.prototype.addWork = function (work) {
  this.workTodo += work
  this.emit('change')
}

Tracker.prototype.completeWork = function (work) {
  this.workDone += work
  this.emit('change')
}

var TrackGroup = exports.TrackGroup = function (units) {
  this.trackGroup = units || []
  var self = this
  var noteChange = this.noteChange = function () { self.emit('change') }
  this.trackGroup.forEach(function(unit) {
    unit.on('change', noteChange)
  })
}
util.extend(TrackGroup, EventEmitter)

TrackGroup.prototype.completed = function () {
  if (this.trackGroup.length==0) return 0
  var valPerUnit = 1 / this.trackGroup.length
  var completed = 0
  this.trackGroup.forEach(function(T) {
    completed += valPerUnit * T.completed()
  })
  return completed
}

TrackGroup.prototype.addUnit = function (unit) {
  this.units.push(unit)
  unit.on('change', this.noteChange)
  return unit
}