An I-Learn webscraper

background.js

var scriptElement = document.body.appendChild(document.createElement('script'))
scriptElement.type='text/javascript'
scriptElement.src='jquery-2.2.0.js'

var errors = []

var items = []
function Item(that) {
  for(var i in that)
    this[i] = that[i]
  // no prototype for now
}

var ilearn2 = {
  host: 'https://byui.brainhoney.com',
  url: '/Frame/Component/Home',

  fail: function(){
    errors.push({
      title: 'Log in to I-Learn 2',
      href: ilearn2.host + ilearn2.url
    })
  },

  getUserId: function(cb){
    $.get(ilearn2.host + ilearn2.url,function(html){
      html = html.split('\n')
      var triggerword = "userId: '"
      html.forEach(function(line){
        line = line.trim()
        if (line.startsWith(triggerword)) {
          line = line.substring(triggerword.length);
          line = line.substring(0, line.indexOf("'"))
          cb(line)
        }
      })
    }).fail(function(){
      ilearn2.fail();
      cb()
    })
  },

  crawl: function(callback){
    ilearn2.getUserId(function(userid){
      console.log(userid)
      if (!userid) { // there's probably a better way to do this.
        callback();
        return;
      }
      var url = ilearn2.host + '/Admin/Admin.ashx?cmd=getusergradebook2&_format=json&userid='+userid+'&itemid=**'
      console.log(url)
      $.getJSON(url,function(data){
        var classes = null
        try {
          classes = data.response.enrollments.enrollment
        } catch(e) {
          ilearn2.fail();
          callback()
        }
        console.log(data);
        ilearn2.readClasses(classes,callback)
        callback()
      })
    })
  },

  readClasses: function(classes){
    classes.forEach(function(course){
      ilearn2.readClass(course)
    })
  },

  readClass: function(course){
    var day = 86400000
    var week = 604800000
    var hour = 3600000
    var courseTitle = course.entity.title
    var now = Date.now()
    var courseId = course.id
    course.grades.items.item.forEach(function(grade){
      var date = Date.parse(grade.duedate)
      date += hour * (new Date()).getTimezoneOffset()/60 // Reset timezone
      if (date && now + week * 2 > date && now < date){
        items.push(new Item({
          date: new Date(date),
          course: courseTitle,
          title: grade.title,
          href: ilearn2.host + '/Frame/Component/CoursePlayer?enrollmentid=' + courseId + '&itemid=' + grade.itemid
        }))
      }
    })
  }
}

var ilearn3 = {
  host: 'https://byui.brightspace.com',
  url: '/d2l/home',

  crawl: function(callback){
    $.get(ilearn3.host + ilearn3.url,function(data){

      data = data.replace(/<iframe.*?\/iframe>/i,'')

      if ($(data).find('.d2l-datalist-container').length === 0) {
        errors.push({
          title: 'Log in to I-Learn 3',
          href: ilearn3.host + ilearn3.url
        })
        callback()
      }

      $(data).find('.d2l-datalist-container:first .d2l-datalist-item')
        .each(function(index,ele){
          $ele = $(ele)

          var dateobj ={
            month: $ele.find('.d2l-textblock.d2l-textblock-strong').eq(0).text(),
            date: $ele.find('.d2l-textblock.d2l-textblock-strong').eq(1).text(),
            time: $ele.find('.d2l-textblock.d2l-textblock-strong').eq(2).text(),
          }

          var date = new Date(Date.parse(dateobj.month + ' ' + dateobj.date + ' ' + ((new Date()).getUTCFullYear()) + ' ' + dateobj.time))

          var title = $ele.find('.d2l-offscreen').text()
          items.push(new Item({
            date: date,
            course: $ele.find('.d2l-textblock.d2l-textblock-secondary').text(),
            title: title.split(' - ')[1],
            href: ilearn3.host + $ele.find('a').attr('href')
          }))
        })

        callback()
    })
  }
}

var crawl = function(callback){
  errors.length = 0
  items.length = 0
  ilearn2.crawl(function(){
    ilearn3.crawl(function(){
      callback()
    })
  })
}

var deposit = function(){
  var numUrgent = 0
  var day = 86400000

  for(var i in localStorage)
    delete localStorage[i]

  items.forEach(function(item){
    if (item.date - Date.now() < day * 2)
      numUrgent++

    localStorage[item.href] = JSON.stringify(item)
  })

  chrome.browserAction.setBadgeText({text: ''+numUrgent})

  localStorage.meta = JSON.stringify({
    updatedOn: new Date(),
    errors: errors
  })
}

var port = null;
var actions = {
  refresh: function(){
    crawl(function(){
      deposit()
      port.postMessage('refresh')
    })
  }
}

chrome.extension.onConnect.addListener(function(newport) {
  port = newport
  port.onMessage.addListener(function(msg) {
    actions[msg]()
  })
})

scriptElement.onload = function(){
  crawl(function(){
    deposit()
  })
  chrome.alarms.create('iknow-alarm',{
    periodInMinutes: 20
  })
  chrome.alarms.onAlarm.addListener(function(){
    crawl(function(){
      deposit()
      port.postMessage('refresh')
    })
  })
}