Update editor content on submission selection

app/assets/javascripts/submission_statistics.js

@@ -0,0 +1,32 @@
+$(function() {
+
+  if ($.isController('exercises') && $('#timeline').isPresent()) {
+
+    var editors = $('.editor');
+    var slider = $('#slider>input');
+    var submissions = $('#data').data('submissions');
+    var files = $('#data').data('files');
+
+    editors.each(function(index, editor) {
+      currentEditor = ace.edit(editor);
+      currentEditor.$blockScrolling = Infinity;
+      currentEditor.setReadOnly(true);
+    });
+
+    slider.on('change', function(event) {
+      var currentSubmission = slider.val();
+      var currentFiles = JSON.parse(files[currentSubmission]);
+
+      editors.each(function(index, editor) {
+        currentEditor = ace.edit(editor);
+        fileContent = "";
+        if (currentFiles[index]) {
+          fileContent = currentFiles[index].content
+        }
+        currentEditor.getSession().setValue(fileContent);
+      });
+    });
+
+  }
+
+});

app/views/exercises/external_users/statistics.html.slim

@@ -4,7 +4,11 @@ h1 = "#{@exercise} (external user #{@external_user})"
 - if current_submission
     - files = current_submission.files.to_a
 
-    .hidden data-submissions=ActiveSupport::JSON.encode(submissions)
+    - all_files = []
+    - submissions.each do |submission|
+        - all_files.push(ActiveSupport::JSON.encode(submission.files))
+
+    .hidden#data data-submissions=ActiveSupport::JSON.encode(submissions) data-files=all_files
 
     #editor.row data-exercise-id=@exercise.id data-message-depleted=t('exercises.editor.depleted') data-user-id=@external_user.id
       div class=(@exercise.hide_file_tree ? 'hidden col-sm-3' : 'col-sm-3') id='files' data-entries=FileTree.new(files).to_js_tree