differencebetweentimes/lib/differencebetweentimes.coffee

A node package to show the difference between two or more formated times.

_   = require 'underscore'
pad = require 'pad'

differenceBetweenTimes =
  version: '0.0.1'
  standardLimiter: /(\.|:)/
  timeUnits: ['Milliseconds', 'Seconds', 'Minutes', 'Hours']

  convert: (timeString) ->
    date = new Date 0

    explodedTimeString = _.filter timeString.split(@standardLimiter), (chunk) ->
      return true if parseInt(chunk, 10) == 0
      !!parseInt(chunk, 10)
    .reverse()

    for chunk, index in explodedTimeString
      date["set#{@timeUnits[index]}"](chunk)

    date.getTime()

  convertToTimeString: (timeStamp) ->
    timeStamp = timeStamp * -1 if timeStamp < 0
    time = new Date timeStamp

    return @convertTimeStringWithoutMinutes time if timeStamp < 60000
    @converToTimeStringWithMinutes time

  converToTimeStringWithMinutes: (timeStamp) ->
    minutes = pad 2, timeStamp.getMinutes(), '0'
    seconds = pad 2, timeStamp.getSeconds(), '0'
    milliseconds = pad 3, timeStamp.getMilliseconds(), '0'

    "#{minutes}:#{seconds}.#{milliseconds}"

  convertTimeStringWithoutMinutes: (timeStamp) ->
    seconds = pad 2, timeStamp.getSeconds(), '0'
    milliseconds = pad 3, timeStamp.getMilliseconds(), '0'

    "#{seconds}.#{milliseconds}"

  difference: (timesArray) ->
    differences = []

    for time, index in timesArray
      if index == 0
        differences[0] = time
      else
        differences.push time - timesArray[0]

    differences

  differenceBetweenTimes: (timeStringsArray) ->
    convertedArray = _.map timeStringsArray, (timeString) =>
      @convert timeString

    differences = [timeStringsArray[0]]

    for time in convertedArray.slice 1
      diff = @difference([convertedArray[0], time])[1]
      differences.push if diff < 0
        "-#{@convertToTimeString diff}"
      else
        "+#{@convertToTimeString diff}"

    differences

module.exports = differenceBetweenTimes