Practice levels Ux and next level algorithm

Update classroom and gameplay Ux to surface practice levels as 3a, 3b,
etc.
Update next level logic to leverage practice levels based on per level
completion playtime thresholds.
Patrol buster and patrol buster A are live for testing.
Fix a few classroom Ux progress hover bubble info bugs.

Closes #3767

app/core/utils.coffee

@@ -325,3 +325,48 @@ module.exports.capitalLanguages = capitalLanguages =
   'python': 'Python'
   'java': 'Java'
   'lua': 'Lua'
+
+module.exports.createLevelNumberMap = (levels) ->
+  levelNumberMap = {}
+  practiceLevelTotalCount = 0
+  practiceLevelCurrentCount = 0
+  for level, i in levels
+    levelNumber = i - practiceLevelTotalCount + 1
+    if level.practice
+      levelNumber = i - practiceLevelTotalCount + String.fromCharCode('a'.charCodeAt(0) + practiceLevelCurrentCount)
+      practiceLevelTotalCount++
+      practiceLevelCurrentCount++
+    else
+      practiceLevelCurrentCount = 0
+    levelNumberMap[level.key] = levelNumber
+  levelNumberMap
+
+module.exports.findNextLevel = (levels, currentIndex, needsPractice) ->
+    # levels = [{practice: true/false, complete: true/false}]
+    index = currentIndex
+    index++
+    if needsPractice
+      if levels[currentIndex].practice or index < levels.length and levels[index].practice
+        # Needs practice, on practice or next practice, choose next incomplete level
+        # May leave earlier practice levels incomplete and reach end of course
+        index++ while index < levels.length and levels[index].complete
+      else
+        # Needs practice, on required, next required, choose first incomplete level of previous practice chain
+        index--
+        index-- while index >= 0 and not levels[index].practice
+        if index >= 0
+          index-- while index >= 0 and levels[index].practice
+          if index >= 0
+            index++
+            index++ while index < levels.length and levels[index].practice and levels[index].complete
+            if levels[index].practice and not levels[index].complete
+              return index
+        index = currentIndex + 1
+        index++ while index < levels.length and levels[index].complete
+    else
+      # No practice needed, next required incomplete level
+      index++ while index < levels.length and (levels[index].practice or levels[index].complete)
+    index
+
+module.exports.needsPractice = (playtime=0, threshold=2) ->
+  playtime / 60 > threshold

app/locale/en.coffee

@@ -295,6 +295,7 @@
     saving: "Saving..."
     sending: "Sending..."
     send: "Send"
+    type: "Type"
     cancel: "Cancel"
     save: "Save"
     publish: "Publish"

app/models/Campaign.coffee

@@ -3,6 +3,7 @@ schema = require 'schemas/models/campaign.schema'
 Level = require 'models/Level'
 Levels = require 'collections/Levels'
 CocoCollection = require 'collections/CocoCollection'
+utils = require '../core/utils'
 
 module.exports = class Campaign extends CocoModel
   @className: 'Campaign'
@@ -23,3 +24,11 @@ module.exports = class Campaign extends CocoModel
     levels.comparator = 'campaignIndex'
     levels.sort()
     return levels
+
+  getLevelNumber: (levelID, defaultNumber) ->
+    unless @levelNumberMap
+      levels = []
+      for level in @getLevels().models when level.get('original')
+        levels.push({key: level.get('original'), practice: level.get('practice') ? false})
+      @levelNumberMap = utils.createLevelNumberMap(levels)
+    @levelNumberMap[levelID] ? defaultNumber

app/models/Classroom.coffee

@@ -1,6 +1,6 @@
 CocoModel = require './CocoModel'
 schema = require 'schemas/models/classroom.schema'
-utils = require 'core/utils'
+utils = require '../core/utils'
 User = require 'models/User'
 
 module.exports = class Classroom extends CocoModel
@@ -44,6 +44,16 @@ module.exports = class Classroom extends CocoModel
     _.extend options, opts
     @fetch(options)
 
+  getLevelNumber: (levelID, defaultNumber) ->
+    unless @levelNumberMap
+      @levelNumberMap = {}
+      for course in @get('courses') ? []
+        levels = []
+        for level in course.levels when level.original
+          levels.push({key: level.original, practice: level.practice ? false})
+        _.assign(@levelNumberMap, utils.createLevelNumberMap(levels))
+    @levelNumberMap[levelID] ? defaultNumber
+
   removeMember: (userID, opts) ->
     options = {
       url: _.result(@, 'url') + '/members'
@@ -88,30 +98,59 @@ module.exports = class Classroom extends CocoModel
 
   statsForSessions: (sessions, courseID) ->
     return null unless sessions
-    stats = {}
     sessions = sessions.models or sessions
     arena = @getLadderLevel(courseID)
-    levels = @getLevels({courseID: courseID, withoutLadderLevels: true})
+    courseLevels = @getLevels({courseID: courseID, withoutLadderLevels: true})
-    levelOriginals = levels.pluck('original')
+    levelSessionMap = {}
-    completeSessionOriginals = (session.get('level').original for session in sessions when session.get('state').complete)
+    levelSessionMap[session.get('level').original] = session for session in sessions
-    incompleteSessionOriginals = (session.get('level').original for session in sessions when not session.get('state').complete)
+    currentIndex = -1
-    levelsLeft = _.size(_.difference(levelOriginals, completeSessionOriginals))
+    lastStarted = null
-    next = _.find levels.models, (level) -> level.get('original') not in completeSessionOriginals
+    levelsTotal = 0
-    lastPlayed = _.find levels.models, (level) -> level.get('original') in incompleteSessionOriginals
+    levelsLeft = 0
-    stats.levels = {
+    lastPlayed = null
-      size: levels.size()
+    playtime = 0
+    levels = []
+    for level, index in courseLevels.models
+      levelsTotal++ unless level.get('practice')
+      complete = false
+      if session = levelSessionMap[level.get('original')]
+        complete = session.get('state').complete ? false
+        playtime += session.get('playtime') ? 0
+        lastPlayed = level
+        if complete
+          currentIndex = index
+        else
+          lastStarted = level
+          levelsLeft++ unless level.get('practice')
+      else if not level.get('practice')
+        levelsLeft++
+      levels.push
+        practice: level.get('practice') ? false
+        complete: complete
+    lastPlayed = lastStarted ? lastPlayed
+    needsPractice = false
+    nextIndex = 0
+    if currentIndex >= 0
+      currentLevel = courseLevels.models[currentIndex]
+      currentPlaytime = levelSessionMap[currentLevel.get('original')]?.get('playtime') ? 0
+      needsPractice = utils.needsPractice(currentPlaytime, currentLevel.get('practiceThresholdMinutes'))
+      nextIndex = utils.findNextLevel(levels, currentIndex, needsPractice)
+    nextLevel = courseLevels.models[nextIndex]
+    nextLevel ?= _.find courseLevels.models, (level) -> not levelSessionMap[level.get('original')]?.get('state')?.complete
+
+    stats =
+      levels:
+        size: levelsTotal
         left: levelsLeft
         done: levelsLeft is 0
-      numDone: levels.size() - levelsLeft
+        numDone: levelsTotal - levelsLeft
-      pctDone: (100 * (levels.size() - levelsLeft) / levels.size()).toFixed(1) + '%'
+        pctDone: (100 * (levelsTotal - levelsLeft) / levelsTotal).toFixed(1) + '%'
         lastPlayed: lastPlayed
-      next: next
+        next: nextLevel
-      first: levels.first()
+        first: courseLevels.first()
         arena: arena
-    }
+      playtime: playtime
-    sum = (nums) -> _.reduce(nums, (s, num) -> s + num) or 0
+    stats
-    stats.playtime = sum((session.get('playtime') or 0 for session in sessions))
-    return stats
 
   fetchForCourseInstance: (courseInstanceID, options={}) ->
     return unless courseInstanceID

app/models/Level.coffee

@@ -262,9 +262,9 @@ module.exports = class Level extends CocoModel
   isLadder: ->
     return @get('type')?.indexOf('ladder') > -1
 
-  fetchNextForCourse: ({ levelOriginalID, courseInstanceID, courseID }, options={}) ->
+  fetchNextForCourse: ({ levelOriginalID, courseInstanceID, courseID, sessionID }, options={}) ->
     if courseInstanceID
-      options.url = "/db/course_instance/#{courseInstanceID}/levels/#{levelOriginalID}/next"
+      options.url = "/db/course_instance/#{courseInstanceID}/levels/#{levelOriginalID}/sessions/#{sessionID}/next"
     else
       options.url = "/db/course/#{courseID}/levels/#{levelOriginalID}/next"
     @fetch(options)

app/schemas/models/campaign.schema.coffee

@@ -66,6 +66,7 @@ _.extend CampaignSchema.properties, {
       original: { type: 'string', format: 'hidden' }
       adventurer: { type: 'boolean' }
       practice: { type: 'boolean' }
+      practiceThresholdMinutes: {type: 'number'}
       adminOnly: { type: 'boolean' }
       disableSpaces: { type: ['boolean','number'] }
       hidesSubmitUntilRun: { type: 'boolean' }

app/schemas/models/classroom.schema.coffee

@@ -23,6 +23,8 @@ _.extend ClassroomSchema.properties,
   courses: c.array { title: 'Courses' }, c.object { title: 'Course' }, {
     _id: c.objectId()
     levels: c.array { title: 'Levels' }, c.object { title: 'Level' }, {
+      practice: {type: 'boolean'}
+      practiceThresholdMinutes: {type: 'number'}
       type: c.shortString()
       original: c.objectId()
       name: {type: 'string'}

app/templates/courses/classroom-view.jade

@@ -32,10 +32,6 @@ block content
         td(data-i18n="courses.total_students")
         td
           span.spr= _.size(view.classroom.get('members'))
-          span (
-          span.spr(data-i18n="courses.enrolled_courses")
-          span= stats.enrolledUsers
-          span )
       tr
         td(data-i18n="courses.average_time")
         td= stats.averagePlaytime
@@ -108,16 +104,17 @@ block content
                 .progress
                   each trimModel in levels.models
                     - var level = view.levels.get(trimModel.get('original')); // get the level loaded through the db
+                    - var levelNumber = view.classroom.getLevelNumber(level.get('original'), i + 1)
                     - i++
                     - var session = sessionMap[level.get('original')];
                     a(href=view.getLevelURL(level, course, courseInstance, session))
-                      - var content = view.levelPopoverContent(level, session, i);
+                      - var content = view.levelPopoverContent(level, session, levelNumber);
                       if session && session.get('state') && session.get('state').complete
-                        .progress-bar.progress-bar-complete(style=css, data-content=content, data-toggle='popover')= i
+                        .progress-bar.progress-bar-complete(style=css, data-content=content, data-toggle='popover')= levelNumber
                       else if session
-                        .progress-bar.progress-bar-started(style=css, data-content=content, data-toggle='popover')= i
+                        .progress-bar.progress-bar-started(style=css, data-content=content, data-toggle='popover')= levelNumber
                       else
-                        .progress-bar.progress-bar-default(style=css, data-content=content, data-toggle='popover')= i
+                        .progress-bar.progress-bar-default(style=css, data-content=content, data-toggle='popover')= levelNumber
         else if paidFor
           .text-center
             button.enable-btn.btn.btn-info.btn-sm.text-uppercase(data-user-id=user.id, data-course-instance-cid=courseInstance.cid)

app/templates/courses/course-details.jade

@@ -88,6 +88,7 @@ block content
       tr
         th
         th(data-i18n="clans.status")
+        th(data-i18n="common.type")
         th(data-i18n="resources.level")
         th(data-i18n="courses.concepts")
     tbody
@@ -97,6 +98,7 @@ block content
       - var levelCount = 0;
       each level in view.levels.models
         - var levelStatus = null;
+        - var levelNumber = view.classroom.getLevelNumber(level.get('original'), ++levelCount);
         if view.userLevelStateMap[me.id]
           - levelStatus = view.userLevelStateMap[me.id][level.get('original')]
         tr
@@ -107,10 +109,8 @@ block content
           td
             if view.userLevelStateMap[me.id]
               div= view.userLevelStateMap[me.id][level.get('original')]
-              - previousLevelCompleted = view.userLevelStateMap[me.id][level.get('original')] === 'complete'
+          td #{level.get('practice') ? 'practice' : 'required'}
-            else
+          td #{levelNumber}. #{level.get('name').replace('Course: ', '')} 
-              - previousLevelCompleted = false
-          td= ++levelCount + '. ' + level.get('name').replace('Course: ', '')
           td
             if view.levelConceptMap[level.get('original')]
               each concept in view.course.get('concepts')
@@ -118,3 +118,8 @@ block content
                   span.spr.concept(data-i18n="concepts." + concept)
           if level.get('original') === lastLevelCompleted
             - passedLastCompletedLevel = true
+          if !level.get('practice')
+            if view.userLevelStateMap[me.id]
+              - previousLevelCompleted = view.userLevelStateMap[me.id][level.get('original')] === 'complete'
+            else
+              - previousLevelCompleted = false

app/templates/courses/teacher-class-view.jade

@@ -309,7 +309,8 @@ mixin courseOverview
     .course-overview-progress
       each level, index in levels
         - var progress = state.get('progressData').get({ classroom: view.classroom, course: course, level: level })
-        +allStudentsLevelProgressDot(progress, level, index+1)
+        - var levelNumber = view.classroom.getLevelNumber(level.get('original'), index + 1)
+        +allStudentsLevelProgressDot(progress, level, levelNumber)
 
 mixin studentLevelsRow(student)
   .student-levels-row.alternating-background
@@ -321,7 +322,8 @@ mixin studentLevelsRow(student)
       - var levels = view.classroom.getLevels({courseID: course.id}).models
       each level, index in levels
         - var progress = state.get('progressData').get({ classroom: view.classroom, course: course, level: level, user: student })
-        +studentLevelProgressDot(progress, level, index+1, session)
+        - var levelNumber = view.classroom.getLevelNumber(level.get('original'), index + 1)
+        +studentLevelProgressDot(progress, level, levelNumber, session)
   
 mixin studentCourseProgressDot(progress, levelsTotal, level, label)
   //- TODO: Refactor with TeacherClassesView jade

app/templates/courses/teacher-courses-view.jade

@@ -56,12 +56,12 @@ block content
                   | :
                   select.level-select.form-control
                     if view.campaigns.loaded
-                      each level, levelIndex in view.campaigns.get(course.get('campaignID')).getLevels().models
+                      - var campaign = view.campaigns.get(course.get('campaignID'))
-                        if level.get('practice')
+                      each level, levelIndex in campaign.getLevels().models
-                          - continue;
+                        - var levelNumber = campaign.getLevelNumber(level.get('original'), levelIndex + 1)
                         option(value=level.get('slug'))
                           span
-                            = levelIndex + 1
+                            = levelNumber
                           span.spr
                             | . 
                           span

app/templates/play/level/control_bar.jade

@@ -22,7 +22,7 @@ else
     .level-name-area
       .level-label(data-i18n="play_level.level")
       .level-name(title=difficultyTitle || "")
-        span= (campaignIndex ? campaignIndex + '. ' : '') + worldName.replace('Course: ', '')
+        span #{view.levelNumber ? view.levelNumber + '. ' : ''}#{worldName.replace('Course: ', '')}
         if levelDifficulty
           sup.level-difficulty= levelDifficulty
 

app/templates/teachers/hovers/progress-dot-all-students-single-level.jade

@@ -17,5 +17,9 @@ if started
   //- .small-details
   //-   i(data-i18n='teacher.click_to_view_progress')
 else
+  .small-details.nowrap
+    span= levelNumber
+    span.spr . 
+    span= levelName
   span.small-details.nowrap(data-i18n='teacher.no_progress')
     | No progress

app/templates/teachers/hovers/progress-dot-single-student-level.jade

@@ -13,7 +13,7 @@ if completed
   .small-details.nowrap
     span.spr(data-i18n='teacher.completed')
       | Completed
-    span= new Date(dateFirstCompleted).toLocaleString()
+    span= new Date(session.get('dateFirstCompleted')).toLocaleString()
     +timePlayed
   //- .small-details
   //-   i(data-i18n='teacher.click_to_view_solution')
@@ -26,11 +26,15 @@ else if started
   .small-details.nowrap
     span.spr(data-i18n='teacher.last_played')
       | Last played
-    span= new Date(lastPlayed).toLocaleString()
+    span= new Date(session.get('changed')).toLocaleString()
     +timePlayed
   //- .small-details
   //-   i(data-i18n='teacher.click_to_view_progress')
   //-     | click to view progress
 else
+  .small-details.nowrap
+    span= levelNumber
+    span.spr . 
+    span= levelName
   span.small-details.nowrap(data-i18n='teacher.no_progress')
     | No progress

app/views/courses/ClassroomView.coffee

@@ -55,7 +55,7 @@ module.exports = class ClassroomView extends RootView
     @ownedClassrooms.fetchMine({data: {project: '_id'}})
     @supermodel.trackCollection(@ownedClassrooms)
     @levels = new Levels()
-    @levels.fetchForClassroom(classroomID, {data: {project: 'name,slug,original'}})
+    @levels.fetchForClassroom(classroomID, {data: {project: 'name,original,practice,slug'}})
     @levels.on 'add', (model) -> @_byId[model.get('original')] = model # so you can 'get' them
     @supermodel.trackCollection(@levels)
     window.tracker?.trackEvent 'Students Class Loaded', category: 'Students', classroomID: classroomID, ['Mixpanel']
@@ -177,7 +177,9 @@ module.exports = class ClassroomView extends RootView
     stats.averagePlaytime = if playtime and total then moment.duration(playtime / total, "seconds").humanize() else 0
     stats.totalPlaytime = if playtime then moment.duration(playtime, "seconds").humanize() else 0
 
-    completeSessions = @sessions.filter (s) -> s.get('state')?.complete
+    levelPracticeMap = {}
+    levelPracticeMap[level.id] = level.get('practice') ? false for level in @levels.models
+    completeSessions = @sessions.filter (s) -> s.get('state')?.complete and not levelPracticeMap[s.get('levelID')]
     stats.averageLevelsComplete = if @users.size() then (_.size(completeSessions) / @users.size()).toFixed(1) else 'N/A'  # '
     stats.totalLevelsComplete = _.size(completeSessions)
 

app/views/courses/CourseDetailsView.coffee

@@ -52,7 +52,7 @@ module.exports = class CourseDetailsView extends RootView
       @supermodel.trackRequest(@classroom.fetch())
 
       levelsLoaded = @supermodel.trackRequest(@levels.fetchForClassroomAndCourse(classroomID, @courseID, {
-        data: { project: 'concepts,type,slug,name,original,description' }
+        data: { project: 'concepts,practice,type,slug,name,original,description' }
       }))
 
       @supermodel.trackRequest($.when(levelsLoaded, sessionsLoaded).then(=>

app/views/courses/TeacherClassView.coffee

@@ -118,7 +118,7 @@ module.exports = class TeacherClassView extends RootView
     @supermodel.trackRequest @courseInstances.fetchForClassroom(classroomID)
 
     @levels = new Levels()
-    @supermodel.trackRequest @levels.fetchForClassroom(classroomID, {data: {project: 'original,concepts'}})
+    @supermodel.trackRequest @levels.fetchForClassroom(classroomID, {data: {project: 'original,concepts,practice'}})
     
     @attachMediatorEvents()
     window.tracker?.trackEvent 'Teachers Class Loaded', category: 'Teachers', classroomID: @classroom.id, ['Mixpanel']
@@ -449,7 +449,9 @@ module.exports = class TeacherClassView extends RootView
     stats.totalPlaytime = if playtime then moment.duration(playtime, "seconds").humanize() else 0
     # TODO: Humanize differently ('1 hour' instead of 'an hour')
 
-    completeSessions = @classroom.sessions.filter (s) -> s.get('state')?.complete
+    levelPracticeMap = {}
+    levelPracticeMap[level.id] = level.get('practice') ? false for level in @levels.models
+    completeSessions = @classroom.sessions.filter (s) -> s.get('state')?.complete and not levelPracticeMap[s.get('levelID')]
     stats.averageLevelsComplete = if @students.size() then (_.size(completeSessions) / @students.size()).toFixed(1) else 'N/A'  # '
     stats.totalLevelsComplete = _.size(completeSessions)
 

app/views/play/level/ControlBarView.coffee

@@ -2,6 +2,10 @@ CocoView = require 'views/core/CocoView'
 template = require 'templates/play/level/control_bar'
 {me} = require 'core/auth'
 
+Campaign = require 'models/Campaign'
+Classroom = require 'models/Classroom'
+Course = require 'models/Course'
+CourseInstance = require 'models/CourseInstance'
 GameMenuModal = require 'views/play/menu/GameMenuModal'
 RealTimeModel = require 'models/RealTimeModel'
 RealTimeCollection = require 'collections/RealTimeCollection'
@@ -28,6 +32,7 @@ module.exports = class ControlBarView extends CocoView
     'click #control-bar-sign-up-button': 'onClickSignupButton'
 
   constructor: (options) ->
+    @supermodel = options.supermodel
     @courseID = options.courseID
     @courseInstanceID = options.courseInstanceID
 
@@ -38,6 +43,26 @@ module.exports = class ControlBarView extends CocoView
     @levelID = @levelSlug or @level.id
     @spectateGame = options.spectateGame ? false
     @observing = options.session.get('creator') isnt me.id
+
+    @levelNumber = ''
+    if @level.get('type') is 'course' and @level.get('campaignIndex')?
+      @levelNumber = @level.get('campaignIndex') + 1
+    if @courseInstanceID
+      @courseInstance = new CourseInstance(_id: @courseInstanceID)
+      jqxhr = @courseInstance.fetch()
+      @supermodel.trackRequest(jqxhr)
+      new Promise(jqxhr.then).then(=>
+        @classroom = new Classroom(_id: @courseInstance.get('classroomID'))
+        @supermodel.trackRequest @classroom.fetch()
+      )
+    else if @courseID
+      @course = new Course(_id: @courseID)
+      jqxhr = @course.fetch()
+      @supermodel.trackRequest(jqxhr)
+      new Promise(jqxhr.then).then(=>
+        @campaign = new Campaign(_id: @course.get('campaignID'))
+        @supermodel.trackRequest(@campaign.fetch())
+      )
     super options
     if @level.get('type') in ['hero-ladder', 'course-ladder'] and me.isAdmin()
       @isMultiplayerLevel = true
@@ -45,6 +70,13 @@ module.exports = class ControlBarView extends CocoView
     if @level.get 'replayable'
       @listenTo @session, 'change-difficulty', @onSessionDifficultyChanged
 
+  onLoaded: ->
+    if @classroom
+      @levelNumber = @classroom.getLevelNumber(@level.get('original'), @levelNumber)
+    else if @campaign
+      @levelNumber = @campaign.getLevelNumber(@level.get('original'), @levelNumber)
+    super()
+
   setBus: (@bus) ->
 
   onPlayerStatesChanged: (e) ->
@@ -62,7 +94,6 @@ module.exports = class ControlBarView extends CocoView
   getRenderData: (c={}) ->
     super c
     c.worldName = @worldName
-    c.campaignIndex = @level.get('campaignIndex') + 1 if @level.get('type') is 'course' and @level.get('campaignIndex')?  # TODO: support 'game-dev' levels in courses
     c.multiplayerEnabled = @session.get('multiplayer')
     c.ladderGame = @level.get('type') in ['ladder', 'hero-ladder', 'course-ladder']
     if c.isMultiplayerLevel = @isMultiplayerLevel

app/views/play/level/modal/CourseVictoryModal.coffee

@@ -43,7 +43,12 @@ module.exports = class CourseVictoryModal extends ModalView
 
     @playSound 'victory'
     @nextLevel = new Level()
-    @nextLevelRequest = @supermodel.trackRequest @nextLevel.fetchNextForCourse({ levelOriginalID: @level.get('original'), @courseInstanceID, @courseID })
+    @nextLevelRequest = @supermodel.trackRequest(@nextLevel.fetchNextForCourse({
+      levelOriginalID: @level.get('original')
+      @courseInstanceID
+      @courseID
+      sessionID: @session.id
+    }))
 
     @course = options.course
     if @courseID and not @course

server/middleware/classrooms.coffee

@@ -151,12 +151,10 @@ module.exports =
       courseData = { _id: course._id, levels: [] }
       campaign = campaignMap[course.get('campaignID').toString()]
       levels = _.values(campaign.get('levels'))
-      # TODO: remove practice filter after classroom Ux supports practice levels
-      levels = _.reject(levels, {'practice': true})
       levels = _.sortBy(levels, 'campaignIndex')
       for level in levels
         levelData = { original: mongoose.Types.ObjectId(level.original) }
-        _.extend(levelData, _.pick(level, 'type', 'slug', 'name'))
+        _.extend(levelData, _.pick(level, 'type', 'slug', 'name', 'practice', 'practiceThresholdMinutes'))
         courseData.levels.push(levelData)
       coursesData.push(courseData)
     classroom.set('courses', coursesData)

server/middleware/course-instances.coffee

@@ -9,8 +9,10 @@ Classroom = require '../models/Classroom'
 Course = require '../models/Course'
 User = require '../models/User'
 Level = require '../models/Level'
+LevelSession = require '../models/LevelSession'
 parse = require '../commons/parse'
 {objectIdFromTimestamp} = require '../lib/utils'
+utils = require '../../app/core/utils'
 Prepaid = require '../models/Prepaid'
 
 module.exports =
@@ -71,35 +73,46 @@ module.exports =
 
   fetchNextLevel: wrap (req, res) ->
     levelOriginal = req.params.levelOriginal
-    if not database.isID(levelOriginal)
+    unless database.isID(levelOriginal) then throw new errors.UnprocessableEntity('Invalid level original ObjectId')
-      throw new errors.UnprocessableEntity('Invalid level original ObjectId')
+    sessionID = req.params.sessionID
-    
+    unless database.isID(sessionID) then throw new errors.UnprocessableEntity('Invalid session ObjectId')
     courseInstance = yield database.getDocFromHandle(req, CourseInstance)
-    if not courseInstance
+    unless courseInstance then throw new errors.NotFound('Course Instance not found.')
-      throw new errors.NotFound('Course Instance not found.')
-    courseID = courseInstance.get('courseID')
-
     classroom = yield Classroom.findById courseInstance.get('classroomID')
-    if not classroom
+    unless classroom then throw new errors.NotFound('Classroom not found.')
-      throw new errors.NotFound('Classroom not found.')
+    currentLevel = yield Level.findOne({original: mongoose.Types.ObjectId(levelOriginal)}, {practiceThresholdMinutes: 1, type: 1})
+    unless currentLevel then throw new errors.NotFound('Current level not found.')
 
-    nextLevelOriginal = null
+    courseID = courseInstance.get('courseID')
-    foundLevelOriginal = false
+    courseLevels = []
-    for course in classroom.get('courses') or []
+    courseLevels = course.levels for course in classroom.get('courses') or [] when courseID.equals(course._id)
-      if not courseID.equals(course._id)
-        continue
-      for level, index in course.levels
-        if level.original.toString() is levelOriginal
-          foundLevelOriginal = true
-          nextLevelOriginal = course.levels[index+1]?.original
-          break
 
-    if not foundLevelOriginal
+    # Get level completions and playtime
-      throw new errors.NotFound('Level original ObjectId not found in Classroom courses')
+    currentLevelSession = null
+    levelIDs = (level.original.toString() for level in courseLevels)
+    query = {$and: [{creator: req.user.id}, {'level.original': {$in: levelIDs}}]}
+    levelSessions = yield LevelSession.find(query, {level: 1, playtime: 1, state: 1})
+    levelCompleteMap = {}
+    for levelSession in levelSessions
+      currentLevelSession = levelSession if levelSession.id is sessionID
+      levelCompleteMap[levelSession.get('level')?.original] = levelSession.get('state')?.complete
+    unless currentLevelSession then throw new errors.NotFound('Level session not found.') 
+    needsPractice = utils.needsPractice(currentLevelSession.get('playtime'), currentLevel.get('practiceThresholdMinutes'))
 
-    if not nextLevelOriginal
+    # Find next level
-      return res.status(200).send({})
+    levels = []
+    currentIndex = -1
+    for level, index in courseLevels
+      currentIndex = index if level.original.toString() is levelOriginal
+      levels.push
+        practice: level.practice ? false
+        complete: levelCompleteMap[level.original?.toString()] or currentIndex is index
+    unless currentIndex >=0 then throw new errors.NotFound('Level original ObjectId not found in Classroom courses')
+    nextLevelIndex = utils.findNextLevel(levels, currentIndex, needsPractice)
+    nextLevelOriginal = courseLevels[nextLevelIndex]?.original
+    unless nextLevelOriginal then return res.status(200).send({})
 
+    # Return full Level object
     dbq = Level.findOne({original: mongoose.Types.ObjectId(nextLevelOriginal)})
     dbq.sort({ 'version.major': -1, 'version.minor': -1 })
     dbq.select(parse.getProjectFromReq(req))
@@ -107,7 +120,6 @@ module.exports =
     level = level.toObject({req: req})
     res.status(200).send(level)
 
-    
   fetchClassroom: wrap (req, res) ->
     courseInstance = yield database.getDocFromHandle(req, CourseInstance)
     if not courseInstance

server/middleware/levels.coffee

@@ -55,6 +55,7 @@ module.exports =
         classroomID = courseInstance.get('classroomID')
         continue unless classroomID
         classroom = classroomMap[classroomID.toString()]
+        continue unless classroom
         courseID = courseInstance.get('courseID')
         classroomCourse = _.find(classroom.get('courses'), (c) -> c._id.equals(courseID))
         for courseLevel in classroomCourse.levels

server/routes/index.coffee

@@ -81,7 +81,7 @@ module.exports.setup = (app) ->
   app.get('/db/course/:handle/levels/:levelOriginal/next', mw.courses.fetchNextLevel)
 
   app.post('/db/course_instance/-/recent', mw.auth.checkHasPermission(['admin']), mw.courseInstances.fetchRecent)
-  app.get('/db/course_instance/:handle/levels/:levelOriginal/next', mw.courseInstances.fetchNextLevel)
+  app.get('/db/course_instance/:handle/levels/:levelOriginal/sessions/:sessionID/next', mw.courseInstances.fetchNextLevel)
   app.post('/db/course_instance/:handle/members', mw.auth.checkLoggedIn(), mw.courseInstances.addMembers)
   app.get('/db/course_instance/:handle/classroom', mw.auth.checkLoggedIn(), mw.courseInstances.fetchClassroom)
 

spec/server/functional/classrooms.spec.coffee

@@ -144,16 +144,6 @@ describe 'POST /db/classroom', ->
     expect(classroom.get('courses')[0].levels[0].name).toBe('Level A')
     done()
 
-  it 'makes a copy of the list of all non-practice levels in all courses', utils.wrap (done) ->
-    teacher = yield utils.initUser({role: 'teacher'})
-    yield utils.loginUser(teacher)
-    data = { name: 'tmp Classroom 2' }
-    [res, body] = yield request.postAsync {uri: classroomsURL, json: data }
-    classroom = yield Classroom.findById(res.body._id)
-    # console.log(JSON.stringify(classroom.get('courses')[0], null, 2));
-    expect(classroom.get('courses')[0].levels.length).toEqual(2)
-    done()
-
 describe 'GET /db/classroom/:handle/levels', ->
 
   beforeEach utils.wrap (done) ->

spec/server/functional/course_instance.spec.coffee

@@ -9,6 +9,7 @@ User = require '../../../server/models/User'
 Classroom = require '../../../server/models/Classroom'
 Campaign = require '../../../server/models/Campaign'
 Level = require '../../../server/models/Level'
+LevelSession = require '../../../server/models/LevelSession'
 Prepaid = require '../../../server/models/Prepaid'
 request = require '../request'
 moment = require 'moment'
@@ -246,6 +247,7 @@ describe 'GET /db/course_instance/:handle/levels/:levelOriginal/next', ->
     yield utils.clearModels [User, Classroom, Course, Level, Campaign]
     admin = yield utils.initAdmin()
     yield utils.loginUser(admin)
+    teacher = yield utils.initUser({role: 'teacher'})
 
     levelJSON = { name: 'A', permissions: [{access: 'owner', target: admin.id}], type: 'course' }
     [res, body] = yield request.postAsync({uri: getURL('/db/level'), json: levelJSON})
@@ -253,12 +255,25 @@ describe 'GET /db/course_instance/:handle/levels/:levelOriginal/next', ->
     @levelA = yield Level.findById(res.body._id)
     paredLevelA = _.pick(res.body, 'name', 'original', 'type')
 
+    @sessionA = new LevelSession
+      creator: teacher.id
+      level: original: @levelA.get('original').toString()
+      permissions: simplePermissions
+      state: complete: true
+    yield @sessionA.save()
+
     levelJSON = { name: 'B', permissions: [{access: 'owner', target: admin.id}], type: 'course' }
     [res, body] = yield request.postAsync({uri: getURL('/db/level'), json: levelJSON})
     expect(res.statusCode).toBe(200)
     @levelB = yield Level.findById(res.body._id)
     paredLevelB = _.pick(res.body, 'name', 'original', 'type')
 
+    @sessionB = new LevelSession
+      creator: teacher.id
+      level: original: @levelB.get('original').toString()
+      permissions: simplePermissions
+    yield @sessionB.save()
+
     levelJSON = { name: 'C', permissions: [{access: 'owner', target: admin.id}], type: 'course' }
     [res, body] = yield request.postAsync({uri: getURL('/db/level'), json: levelJSON})
     expect(res.statusCode).toBe(200)
@@ -282,7 +297,6 @@ describe 'GET /db/course_instance/:handle/levels/:levelOriginal/next', ->
     @courseB = Course({name: 'Course B', campaignID: @campaignB._id})
     yield @courseB.save()
 
-    teacher = yield utils.initUser({role: 'teacher'})
     yield utils.loginUser(teacher)
     data = { name: 'Classroom 1' }
     classroomsURL = getURL('/db/classroom')
@@ -305,19 +319,19 @@ describe 'GET /db/course_instance/:handle/levels/:levelOriginal/next', ->
     done()
 
   it 'returns the next level for the course in the linked classroom', utils.wrap (done) ->
-    [res, body] = yield request.getAsync { uri: utils.getURL("/db/course_instance/#{@courseInstanceA.id}/levels/#{@levelA.id}/next"), json: true }
+    [res, body] = yield request.getAsync { uri: utils.getURL("/db/course_instance/#{@courseInstanceA.id}/levels/#{@levelA.id}/sessions/#{@sessionA.id}/next"), json: true }
     expect(res.statusCode).toBe(200)
     expect(res.body.original).toBe(@levelB.original.toString())
     done()
 
   it 'returns empty object if the given level is the last level in its course', utils.wrap (done) ->
-    [res, body] = yield request.getAsync { uri: utils.getURL("/db/course_instance/#{@courseInstanceA.id}/levels/#{@levelB.id}/next"), json: true }
+    [res, body] = yield request.getAsync { uri: utils.getURL("/db/course_instance/#{@courseInstanceA.id}/levels/#{@levelB.id}/sessions/#{@sessionB.id}/next"), json: true }
     expect(res.statusCode).toBe(200)
     expect(res.body).toEqual({})
     done()
 
   it 'returns 404 if the given level is not in the course instance\'s course', utils.wrap (done) ->
-    [res, body] = yield request.getAsync { uri: utils.getURL("/db/course_instance/#{@courseInstanceB.id}/levels/#{@levelA.id}/next"), json: true }
+    [res, body] = yield request.getAsync { uri: utils.getURL("/db/course_instance/#{@courseInstanceB.id}/levels/#{@levelA.id}/sessions/#{@sessionA.id}/next"), json: true }
     expect(res.statusCode).toBe(404)
     done()
 

test/app/core/utils.spec.coffee

@@ -1,5 +1,5 @@
 describe 'Utility library', ->
-  util = require 'core/utils'
+  utils = require 'core/utils'
 
   describe 'i18n', ->
     beforeEach ->
@@ -25,24 +25,217 @@ describe 'Utility library', ->
             'text': 'Godagens, trollkarl! Kommit för att öva? Nå, låt oss börja...'
 
     it 'i18n should find a valid target string', ->
-      expect(util.i18n(this.fixture1, 'text', 'sv')).toEqual(this.fixture1.i18n['sv'].text)
+      expect(utils.i18n(this.fixture1, 'text', 'sv')).toEqual(this.fixture1.i18n['sv'].text)
-      expect(util.i18n(this.fixture1, 'text', 'es-ES')).toEqual(this.fixture1.i18n['es-ES'].text)
+      expect(utils.i18n(this.fixture1, 'text', 'es-ES')).toEqual(this.fixture1.i18n['es-ES'].text)
 
     it 'i18n picks the correct fallback for a specific language', ->
-      expect(util.i18n(this.fixture1, 'text', 'fr-be')).toEqual(this.fixture1.i18n['fr'].text)
+      expect(utils.i18n(this.fixture1, 'text', 'fr-be')).toEqual(this.fixture1.i18n['fr'].text)
 
     it 'i18n picks the correct fallback', ->
-      expect(util.i18n(this.fixture1, 'text', 'nl')).toEqual(this.fixture1.i18n['en'].text)
+      expect(utils.i18n(this.fixture1, 'text', 'nl')).toEqual(this.fixture1.i18n['en'].text)
-      expect(util.i18n(this.fixture1, 'text', 'nl', 'de')).toEqual(this.fixture1.i18n['de'].text)
+      expect(utils.i18n(this.fixture1, 'text', 'nl', 'de')).toEqual(this.fixture1.i18n['de'].text)
 
     it 'i18n falls back to the default text, even for other targets (like blurb)', ->
       delete this.fixture1.i18n['en']
-      expect(util.i18n(this.fixture1, 'text', 'en')).toEqual(this.fixture1.text)
+      expect(utils.i18n(this.fixture1, 'text', 'en')).toEqual(this.fixture1.text)
-      expect(util.i18n(this.fixture1, 'blurb', 'en')).toEqual(this.fixture1.blurb)
+      expect(utils.i18n(this.fixture1, 'blurb', 'en')).toEqual(this.fixture1.blurb)
       delete this.fixture1.blurb
-      expect(util.i18n(this.fixture1, 'blurb', 'en')).toEqual(null)
+      expect(utils.i18n(this.fixture1, 'blurb', 'en')).toEqual(null)
 
     it 'i18n can fall forward if a general language is not found', ->
-      expect(util.i18n(this.fixture1, 'text', 'pt')).toEqual(this.fixture1.i18n['pt-BR'].text)
+      expect(utils.i18n(this.fixture1, 'text', 'pt')).toEqual(this.fixture1.i18n['pt-BR'].text)
 
-  describe 'Miscellaneous utility', ->
+  describe 'createLevelNumberMap', ->
+    it 'returns correct map for r', ->
+      levels = [
+        {key: 1, practice: false}
+      ]
+      levelNumberMap = utils.createLevelNumberMap(levels)
+      expect((val.toString() for key, val of levelNumberMap)).toEqual(['1'])
+    it 'returns correct map for r r', ->
+      levels = [
+        {key: 1, practice: false}
+        {key: 2, practice: false}
+      ]
+      levelNumberMap = utils.createLevelNumberMap(levels)
+      expect((val.toString() for key, val of levelNumberMap)).toEqual(['1', '2'])
+    it 'returns correct map for p', ->
+      levels = [
+        {key: 1, practice: true}
+      ]
+      levelNumberMap = utils.createLevelNumberMap(levels)
+      expect((val.toString() for key, val of levelNumberMap)).toEqual(['0a'])
+    it 'returns correct map for r p r', ->
+      levels = [
+        {key: 1, practice: false}
+        {key: 2, practice: true}
+        {key: 3, practice: false}
+      ]
+      levelNumberMap = utils.createLevelNumberMap(levels)
+      expect((val.toString() for key, val of levelNumberMap)).toEqual(['1', '1a', '2'])
+    it 'returns correct map for r p p p', ->
+      levels = [
+        {key: 1, practice: false}
+        {key: 2, practice: true}
+        {key: 3, practice: true}
+        {key: 4, practice: true}
+      ]
+      levelNumberMap = utils.createLevelNumberMap(levels)
+      expect((val.toString() for key, val of levelNumberMap)).toEqual(['1', '1a', '1b', '1c'])
+    it 'returns correct map for r p p p r p p r r p r', ->
+      levels = [
+        {key: 1, practice: false}
+        {key: 2, practice: true}
+        {key: 3, practice: true}
+        {key: 4, practice: true}
+        {key: 5, practice: false}
+        {key: 6, practice: true}
+        {key: 7, practice: true}
+        {key: 8, practice: false}
+        {key: 9, practice: false}
+        {key: 10, practice: true}
+        {key: 11, practice: false}
+      ]
+      levelNumberMap = utils.createLevelNumberMap(levels)
+      expect((val.toString() for key, val of levelNumberMap)).toEqual(['1', '1a', '1b', '1c', '2', '2a', '2b', '3', '4', '4a', '5'])
+
+  describe 'findNextlevel', ->
+    describe 'when no practice needed', ->
+      needsPractice = false
+      it 'returns next level when rc* p', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: false}
+        ]
+        expect(utils.findNextLevel(levels, 0, needsPractice)).toEqual(2)
+        done()
+      it 'returns next level when pc* p r', (done) ->
+        levels = [
+          {practice: true, complete: true}
+          {practice: true, complete: false}
+          {practice: false, complete: false}
+        ]
+        expect(utils.findNextLevel(levels, 0, needsPractice)).toEqual(2)
+        done()
+      it 'returns next level when pc* p p', (done) ->
+        levels = [
+          {practice: true, complete: true}
+          {practice: true, complete: false}
+          {practice: true, complete: false}
+        ]
+        expect(utils.findNextLevel(levels, 0, needsPractice)).toEqual(3)
+        done()
+      it 'returns next level when rc* p rc', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: false}
+          {practice: false, complete: true}
+        ]
+        expect(utils.findNextLevel(levels, 0, needsPractice)).toEqual(3)
+        done()
+    describe 'when needs practice', ->
+      needsPractice = true
+      it 'returns next level when rc* p', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: false}
+        ]
+        expect(utils.findNextLevel(levels, 0, needsPractice)).toEqual(1)
+        done()
+      it 'returns next level when rc* rc', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: false, complete: true}
+        ]
+        expect(utils.findNextLevel(levels, 0, needsPractice)).toEqual(2)
+        done()
+      it 'returns next level when rc p rc*', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: false}
+          {practice: false, complete: true}
+        ]
+        expect(utils.findNextLevel(levels, 2, needsPractice)).toEqual(1)
+        done()
+      it 'returns next level when rc pc p rc*', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+          {practice: true, complete: false}
+          {practice: false, complete: true}
+        ]
+        expect(utils.findNextLevel(levels, 3, needsPractice)).toEqual(2)
+        done()
+      it 'returns next level when rc pc p rc* p', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+          {practice: true, complete: false}
+          {practice: false, complete: true}
+          {practice: true, complete: false}
+        ]
+        expect(utils.findNextLevel(levels, 3, needsPractice)).toEqual(4)
+        done()
+      it 'returns next level when rc pc p rc* pc', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+          {practice: true, complete: false}
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+        ]
+        expect(utils.findNextLevel(levels, 3, needsPractice)).toEqual(5)
+        done()
+      it 'returns next level when rc pc p rc* pc p', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+          {practice: true, complete: false}
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+          {practice: true, complete: false}
+        ]
+        expect(utils.findNextLevel(levels, 3, needsPractice)).toEqual(5)
+        done()
+      it 'returns next level when rc pc p rc* pc r', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+          {practice: true, complete: false}
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+          {practice: false, complete: false}
+        ]
+        expect(utils.findNextLevel(levels, 3, needsPractice)).toEqual(5)
+        done()
+      it 'returns next level when rc pc p rc* pc p r', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+          {practice: true, complete: false}
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+          {practice: true, complete: false}
+          {practice: false, complete: false}
+        ]
+        expect(utils.findNextLevel(levels, 3, needsPractice)).toEqual(5)
+        done()
+      it 'returns next level when rc pc pc rc* r p', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+          {practice: true, complete: true}
+          {practice: false, complete: true}
+          {practice: false, complete: false}
+          {practice: true, complete: false}
+        ]
+        expect(utils.findNextLevel(levels, 3, needsPractice)).toEqual(4)
+        done()
+      it 'returns next level when rc* pc rc', (done) ->
+        levels = [
+          {practice: false, complete: true}
+          {practice: true, complete: true}
+          {practice: false, complete: true}
+        ]
+        expect(utils.findNextLevel(levels, 0, needsPractice)).toEqual(3)
+        done()