Fixed tutorial modal for nonexistent tutorials

app/views/play/ladder/play_modal.coffee

@@ -11,6 +11,7 @@ module.exports = class LadderPlayModal extends View
   closeButton: true
   startsLoading: true
   @shownTutorialButton: false
+  tutorialLevelExists: null
 
   events:
     'click #skip-tutorial-button': 'hideTutorialButtons'
@@ -58,9 +59,11 @@ module.exports = class LadderPlayModal extends View
   # PART 4: Render
 
   finishRendering: ->
-    @startsLoading = false
-    @render()
-    @maybeShowTutorialButtons()
+    @checkTutorialLevelExists (exists) =>
+      @tutorialLevelExists = exists
+      @startsLoading = false
+      @render()
+      @maybeShowTutorialButtons()
 
   getRenderData: ->
     ctx = super()
@@ -94,7 +97,7 @@ module.exports = class LadderPlayModal extends View
     ctx
 
   maybeShowTutorialButtons: ->
-    return if @session or LadderPlayModal.shownTutorialButton
+    return if @session or LadderPlayModal.shownTutorialButton or not @tutorialLevelExists
     @$el.find('#normal-view').addClass('secret')
     @$el.find('.modal-header').addClass('secret')
     @$el.find('#noob-view').removeClass('secret')
@@ -105,6 +108,17 @@ module.exports = class LadderPlayModal extends View
     @$el.find('.modal-header').removeClass('secret')
     @$el.find('#noob-view').addClass('secret')
 
+  checkTutorialLevelExists: (cb) ->
+    levelID = @level.get('slug') or @level.id
+    tutorialLevelID = "#{levelID}-tutorial"
+    success = => cb true
+    failure = => cb false
+    $.ajax
+      type: "GET"
+      url: "/db/level/#{tutorialLevelID}/exists"
+      success: success
+      error: failure
+    
   # Choosing challengers
 
   getChallengers: ->

server/levels/level_handler.coffee

@@ -37,7 +37,7 @@ LevelHandler = class LevelHandler extends Handler
     return @getLeaderboardFacebookFriends(req, res, args[0]) if args[1] is 'leaderboard_facebook_friends'
     return @getLeaderboardGPlusFriends(req, res, args[0]) if args[1] is 'leaderboard_gplus_friends'
     return @getHistogramData(req, res, args[0]) if args[1] is 'histogram_data'
-    
+    return @checkExistence(req, res, args[0]) if args[1] is 'exists'
     return @sendNotFoundError(res)
 
   fetchLevelByIDAndHandleErrors: (id, req, res, callback) ->
@@ -131,6 +131,22 @@ LevelHandler = class LevelHandler extends Handler
       valueArray = _.pluck data, "totalScore"
       @sendSuccess res, valueArray
   
+  checkExistence: (req, res, slugOrID) ->
+    findParameters = {}
+    if Handler.isID slugOrID
+      findParameters["_id"] = slugOrID
+    else
+      findParameters["slug"] = slugOrID
+    selectString = 'original version.major permissions'
+    query = Level.findOne(findParameters)
+    .select(selectString)
+    .lean()
+
+    query.exec (err, level) =>
+      return @sendDatabaseError(res, err) if err
+      return @sendNotFoundError(res) unless level?
+      res.send({"exists":true})
+      res.end()
 
   getLeaderboard: (req, res, id) ->
     sessionsQueryParameters = @makeLeaderboardQueryParameters(req, id)