From b5368f2a4ff71b835c083bd6f0aa45f43c9da1f2 Mon Sep 17 00:00:00 2001
From: Victor Shnayder <victor@mitx.mit.edu>
Date: Tue, 19 Jun 2012 18:16:14 -0400
Subject: [PATCH] Initial progress display.

* add module_from_xml param to I4xSystem
* use it to implement xmodule.get_children()
* fix a few comments here and there
* Render-time progress display for seq and vertical modules.
  - Computes fraction of subproblems done.
* Pass problem state back to js during ajax calls.
* general cleanup in capa_module.py
* add progress_changed and progress fields to json returned from each ajax handler

* Coffeescript changes to hook up sequence tracking of problem progress

* net result: sequence 'a' tags now have a progress class
* properly set css class on initial load
* fire event when progress changes after ajax calls
* also save state in 'progress' property of problems-wrapper tag
* event handler finds those tags, computes updated progress
---
 common/lib/capa/capa_problem.py               |   3 +-
 common/lib/xmodule/capa_module.py             | 240 +++++++++++-------
 common/lib/xmodule/progress.py                |   2 +
 common/lib/xmodule/seq_module.py              |  30 ++-
 common/lib/xmodule/vertical_module.py         |   9 +
 common/lib/xmodule/x_module.py                |   8 +
 lms/djangoapps/courseware/grades.py           |   2 +
 lms/djangoapps/courseware/module_render.py    |  38 ++-
 lms/static/coffee/src/modules/problem.coffee  |  21 +-
 lms/static/coffee/src/modules/sequence.coffee |  59 ++++-
 10 files changed, 309 insertions(+), 103 deletions(-)

diff --git a/common/lib/capa/capa_problem.py b/common/lib/capa/capa_problem.py
index 4ee2a2113d..a06ac1d7b6 100644
--- a/common/lib/capa/capa_problem.py
+++ b/common/lib/capa/capa_problem.py
@@ -169,7 +169,8 @@ class LoncapaProblem(object):
     def get_score(self):
         '''
         Compute score for this problem.  The score is the number of points awarded.
-        Returns an integer, from 0 to get_max_score().
+        Returns a dictionary {'score': integer, from 0 to get_max_score(),
+                              'total': get_max_score()}.
         '''
         correct = 0
         for key in self.correct_map:
diff --git a/common/lib/xmodule/capa_module.py b/common/lib/xmodule/capa_module.py
index 55534f8a3e..7c75d1666a 100644
--- a/common/lib/xmodule/capa_module.py
+++ b/common/lib/xmodule/capa_module.py
@@ -11,6 +11,7 @@ from datetime import timedelta
 from lxml import etree
 
 from x_module import XModule, XModuleDescriptor
+from progress import Progress
 from capa.capa_problem import LoncapaProblem
 from capa.responsetypes import StudentInputError
 
@@ -79,24 +80,41 @@ class Module(XModule):
     def get_xml_tags(c):
         return ["problem"]
 
+
     def get_state(self):
         state = self.lcp.get_state()
         state['attempts'] = self.attempts
         return json.dumps(state)
 
+
     def get_score(self):
         return self.lcp.get_score()
 
+
     def max_score(self):
         return self.lcp.get_max_score()
 
+
+    def get_progress(self):
+        ''' For now, just return score / max_score
+        '''
+        d = self.get_score()
+        score = d['score']
+        total = d['total']
+        return Progress(score, total)
+
+
     def get_html(self):
         return self.system.render_template('problem_ajax.html', {
             'id': self.item_id,
             'ajax_url': self.ajax_url,
         })
 
+
     def get_problem_html(self, encapsulate=True):
+        '''Return html for the problem.  Adds check, reset, save buttons
+        as necessary based on the problem config and state.'''
+
         html = self.lcp.get_html()
         content = {'name': self.name,
                    'html': html,
@@ -109,7 +127,7 @@ class Module(XModule):
         reset_button = True
         save_button = True
 
-        # If we're after deadline, or user has exhuasted attempts,
+        # If we're after deadline, or user has exhausted attempts,
         # question is read-only.
         if self.closed():
             check_button = False
@@ -154,11 +172,13 @@ class Module(XModule):
                    'attempts_used': self.attempts,
                    'attempts_allowed': self.max_attempts,
                    'explain': explain,
+                   'progress': self.get_progress(),
                    }
 
         html = self.system.render_template('problem.html', context)
         if encapsulate:
-            html = '<div id="problem_{id}" class="problem" data-url="{ajax_url}">'.format(id=self.item_id, ajax_url=self.ajax_url) + html + "</div>"
+            html = '<div id="problem_{id}" class="problem" data-url="{ajax_url}">'.format(
+                id=self.item_id, ajax_url=self.ajax_url) + html + "</div>"
 
         return html
 
@@ -170,7 +190,8 @@ class Module(XModule):
 
         dom2 = etree.fromstring(xml)
 
-        self.explanation = "problems/" + only_one(dom2.xpath('/problem/@explain'), default="closed")
+        self.explanation = "problems/" + only_one(dom2.xpath('/problem/@explain'),
+                                                  default="closed")
         # TODO: Should be converted to: self.explanation=only_one(dom2.xpath('/problem/@explain'), default="closed")
         self.explain_available = only_one(dom2.xpath('/problem/@explain_available'))
 
@@ -190,19 +211,19 @@ class Module(XModule):
             self.grace_period = None
             self.close_date = self.display_due_date
 
-        self.max_attempts =only_one(dom2.xpath('/problem/@attempts'))
-        if len(self.max_attempts)>0:
-            self.max_attempts =int(self.max_attempts)
+        self.max_attempts = only_one(dom2.xpath('/problem/@attempts'))
+        if len(self.max_attempts) > 0:
+            self.max_attempts = int(self.max_attempts)
         else:
-            self.max_attempts =None
+            self.max_attempts = None
 
-        self.show_answer =only_one(dom2.xpath('/problem/@showanswer'))
+        self.show_answer = only_one(dom2.xpath('/problem/@showanswer'))
 
-        if self.show_answer =="":
-            self.show_answer ="closed"
+        if self.show_answer == "":
+            self.show_answer = "closed"
 
-        self.rerandomize =only_one(dom2.xpath('/problem/@rerandomize'))
-        if self.rerandomize =="" or self.rerandomize=="always" or self.rerandomize=="true":
+        self.rerandomize = only_one(dom2.xpath('/problem/@rerandomize'))
+        if self.rerandomize == "" or self.rerandomize=="always" or self.rerandomize=="true":
             self.rerandomize="always"
         elif self.rerandomize=="false" or self.rerandomize=="per_student":
             self.rerandomize="per_student"
@@ -253,23 +274,33 @@ class Module(XModule):
 
     def handle_ajax(self, dispatch, get):
         '''
-        This is called by courseware.module_render, to handle an AJAX call.  "get" is request.POST
+        This is called by courseware.module_render, to handle an AJAX call.
+        "get" is request.POST.
+
+        Returns a json dictionary:
+        { 'progress_changed' : True/False,
+          'progress' : 'none'/'in_progress'/'done',
+          <other request-specific values here > }
         '''
-        if dispatch=='problem_get':
-            response = self.get_problem(get)
-        elif False: #self.close_date >
-            return json.dumps({"error":"Past due date"})
-        elif dispatch=='problem_check':
-            response = self.check_problem(get)
-        elif dispatch=='problem_reset':
-            response = self.reset_problem(get)
-        elif dispatch=='problem_save':
-            response = self.save_problem(get)
-        elif dispatch=='problem_show':
-            response = self.get_answer(get)
-        else:
-            return "Error"
-        return response
+        handlers = {
+            'problem_get': self.get_problem,
+            'problem_check': self.check_problem,
+            'problem_reset': self.reset_problem,
+            'problem_save': self.save_problem,
+            'problem_show': self.get_answer,
+            }
+
+        if dispatch not in handlers:
+            return 'Error'
+
+        before = self.get_progress()
+        d = handlers[dispatch](get)
+        after = self.get_progress()
+        d.update({
+            'progress_changed' : after != before,
+            'progress' : after.ternary_str(),
+            })
+        return json.dumps(d, cls=ComplexEncoder)
 
     def closed(self):
         ''' Is the student still allowed to submit answers? '''
@@ -283,24 +314,22 @@ class Module(XModule):
 
     def answer_available(self):
         ''' Is the user allowed to see an answer?
-        TODO: simplify. 
         '''
         if self.show_answer == '':
             return False
+
         if self.show_answer == "never":
             return False
-        if self.show_answer == 'attempted' and self.attempts == 0:
-            return False
-        if self.show_answer == 'attempted' and self.attempts > 0:
-            return True
-        if self.show_answer == 'answered' and self.lcp.done:
-            return True
-        if self.show_answer == 'answered' and not self.lcp.done:
-            return False
-        if self.show_answer == 'closed' and self.closed():
-            return True
-        if self.show_answer == 'closed' and not self.closed():
-            return False
+
+        if self.show_answer == 'attempted':
+            return self.attempts > 0
+
+        if self.show_answer == 'answered':
+            return self.lcp.done
+
+        if self.show_answer == 'closed':
+            return self.closed()
+
         if self.show_answer == 'always':
             return True
         raise self.system.exception404 #TODO: Not 404
@@ -310,45 +339,64 @@ class Module(XModule):
         For the "show answer" button.
 
         TODO: show answer events should be logged here, not just in the problem.js
+
+        Returns the answers: {'answers' : answers}
         '''
         if not self.answer_available():
             raise self.system.exception404
         else:
             answers = self.lcp.get_question_answers()
-            return json.dumps(answers,
-                              cls=ComplexEncoder)
+            return {'answers' : answers}
+
 
     # Figure out if we should move these to capa_problem?
     def get_problem(self, get):
-        ''' Same as get_problem_html -- if we want to reconfirm we
-            have the right thing e.g. after several AJAX calls.'''
-        return self.get_problem_html(encapsulate=False)
+        ''' Return results of get_problem_html, as a simple dict for json-ing.
+        { 'html': <the-html> }
+
+            Used if we want to reconfirm we have the right thing e.g. after
+            several AJAX calls.
+        ''' 
+        return {'html' : self.get_problem_html(encapsulate=False)}
+
+    @staticmethod
+    def make_dict_of_responses(get):
+        '''Make dictionary of student responses (aka "answers")
+        get is POST dictionary.
+        '''
+        answers = dict()
+        for key in get:
+            # e.g. input_resistor_1 ==> resistor_1
+            answers['_'.join(key.split('_')[1:])] = get[key]
+
+        return answers
 
     def check_problem(self, get):
         ''' Checks whether answers to a problem are correct, and
-            returns a map of correct/incorrect answers'''
+            returns a map of correct/incorrect answers:
+
+            {'success' : bool,
+             'contents' : html}
+            '''
         event_info = dict()
         event_info['state'] = self.lcp.get_state()
         event_info['filename'] = self.filename
 
-        # make a dict of all the student responses ("answers").
-        answers=dict()
-        # input_resistor_1 ==> resistor_1
-        for key in get:
-            answers['_'.join(key.split('_')[1:])]=get[key]
+        answers = self.make_dict_of_responses(get)
 
-        event_info['answers']=answers
+        event_info['answers'] = answers
 
         # Too late. Cannot submit
         if self.closed():
-            event_info['failure']='closed'
+            event_info['failure'] = 'closed'
             self.tracker('save_problem_check_fail', event_info)
+            # TODO: probably not 404?
             raise self.system.exception404
 
         # Problem submitted. Student should reset before checking
         # again.
         if self.lcp.done and self.rerandomize == "always":
-            event_info['failure']='unreset'
+            event_info['failure'] = 'unreset'
             self.tracker('save_problem_check_fail', event_info)
             raise self.system.exception404
 
@@ -357,89 +405,107 @@ class Module(XModule):
             lcp_id = self.lcp.problem_id
             correct_map = self.lcp.grade_answers(answers)
         except StudentInputError as inst:
-            self.lcp = LoncapaProblem(self.filestore.open(self.filename), id=lcp_id, state=old_state, system=self.system)
+            # TODO: why is this line here?
+            self.lcp = LoncapaProblem(self.filestore.open(self.filename),
+                                      id=lcp_id, state=old_state, system=self.system)
             traceback.print_exc()
-            return json.dumps({'success':inst.message})
+            return {'success': inst.message}
         except:
-            self.lcp = LoncapaProblem(self.filestore.open(self.filename), id=lcp_id, state=old_state, system=self.system)
+            # TODO: why is this line here?
+            self.lcp = LoncapaProblem(self.filestore.open(self.filename),
+                                      id=lcp_id, state=old_state, system=self.system)
             traceback.print_exc()
             raise Exception,"error in capa_module"
-            return json.dumps({'success':'Unknown Error'})
+            # TODO: Dead code...  is this a bug, or just old?
+            return {'success':'Unknown Error'}
 
         self.attempts = self.attempts + 1
-        self.lcp.done=True
+        self.lcp.done = True
 
-        success = 'correct'				# success = correct if ALL questions in this problem are correct
+        # success = correct if ALL questions in this problem are correct
+        success = 'correct'
         for answer_id in correct_map:
             if not correct_map.is_correct(answer_id):
                 success = 'incorrect'
 
-        event_info['correct_map']=correct_map.get_dict()	# log this in the tracker
-        event_info['success']=success
+        event_info['correct_map'] = correct_map.get_dict()	# log this in the tracker
+        event_info['success'] = success
         self.tracker('save_problem_check', event_info)
 
         try:
             html = self.get_problem_html(encapsulate=False)	# render problem into HTML
         except Exception,err:
             log.error('failed to generate html')
-            raise Exception,err
+            raise Exception, err
+
+        return {'success': success,
+                'contents': html,
+                }
 
-        return json.dumps({'success': success,
-                           'contents': html,
-                           })
 
     def save_problem(self, get):
+        '''
+        Save the passed in answers.
+        Returns a dict { 'success' : bool, ['error' : error-msg]},
+        with the error key only present if success is False.
+        '''
         event_info = dict()
         event_info['state'] = self.lcp.get_state()
         event_info['filename'] = self.filename
 
-        answers=dict()
-        for key in get:
-            answers['_'.join(key.split('_')[1:])]=get[key]
+        answers = self.make_dict_of_responses(get)
         event_info['answers'] = answers
 
         # Too late. Cannot submit
         if self.closed():
-            event_info['failure']='closed'
+            event_info['failure'] = 'closed'
             self.tracker('save_problem_fail', event_info)
-            return "Problem is closed"
+            return {'success': False,
+                    'error': "Problem is closed"}
 
         # Problem submitted. Student should reset before saving
         # again.
         if self.lcp.done and self.rerandomize == "always":
-            event_info['failure']='done'
+            event_info['failure'] = 'done'
             self.tracker('save_problem_fail', event_info)
-            return "Problem needs to be reset prior to save."
+            return {'success' : False,
+                    'error' : "Problem needs to be reset prior to save."}
 
-        self.lcp.student_answers=answers
+        self.lcp.student_answers = answers
 
+        # TODO: should this be save_problem_fail?  Looks like success to me...
         self.tracker('save_problem_fail', event_info)
-        return json.dumps({'success':True})
+        return {'success': True}
 
     def reset_problem(self, get):
         ''' Changes problem state to unfinished -- removes student answers,
-            and causes problem to rerender itself. '''
+            and causes problem to rerender itself.
+
+            Returns problem html as { 'html' : html-string }.
+        ''' 
         event_info = dict()
-        event_info['old_state']=self.lcp.get_state()
-        event_info['filename']=self.filename
+        event_info['old_state'] = self.lcp.get_state()
+        event_info['filename'] = self.filename
 
         if self.closed():
-            event_info['failure']='closed'
+            event_info['failure'] = 'closed'
             self.tracker('reset_problem_fail', event_info)
             return "Problem is closed"
 
         if not self.lcp.done:
-            event_info['failure']='not_done'
+            event_info['failure'] = 'not_done'
             self.tracker('reset_problem_fail', event_info)
             return "Refresh the page and make an attempt before resetting."
 
-        self.lcp.do_reset()		# call method in LoncapaProblem to reset itself
+        self.lcp.do_reset()
         if self.rerandomize == "always":
-            self.lcp.seed=None		# reset random number generator seed (note the self.lcp.get_state() in next line)
- 
-        self.lcp=LoncapaProblem(self.filestore.open(self.filename), self.item_id, self.lcp.get_state(), system=self.system)
+            # reset random number generator seed (note the self.lcp.get_state() in next line)
+            self.lcp.seed=None
+            
+        self.lcp = LoncapaProblem(self.filestore.open(self.filename),
+                                  self.item_id, self.lcp.get_state(), system=self.system)
 
-        event_info['new_state']=self.lcp.get_state()
+        event_info['new_state'] = self.lcp.get_state()
         self.tracker('reset_problem', event_info)
 
-        return json.dumps(self.get_problem_html(encapsulate=False))
+        return {'html' : self.get_problem_html(encapsulate=False)}
diff --git a/common/lib/xmodule/progress.py b/common/lib/xmodule/progress.py
index 1ce5d821f3..b9e242f2b2 100644
--- a/common/lib/xmodule/progress.py
+++ b/common/lib/xmodule/progress.py
@@ -13,6 +13,8 @@ class Progress(object):
 
     Progress can only represent Progress for modules where that makes sense.  Other
     modules (e.g. html) should return None from get_progress().
+
+    TODO: add tag for module type?  Would allow for smarter merging.
     '''
 
     def __init__(self, a, b):
diff --git a/common/lib/xmodule/seq_module.py b/common/lib/xmodule/seq_module.py
index b394227aa7..598fc4443e 100644
--- a/common/lib/xmodule/seq_module.py
+++ b/common/lib/xmodule/seq_module.py
@@ -1,8 +1,12 @@
 import json
+import logging
 
 from lxml import etree
 
 from x_module import XModule, XModuleDescriptor
+from xmodule.progress import Progress
+
+log = logging.getLogger("mitx.common.lib.seq_module")
 
 # HACK: This shouldn't be hard-coded to two types
 # OBSOLETE: This obsoletes 'type'
@@ -37,6 +41,16 @@ class Module(XModule):
         self.render()
         return self.destroy_js
 
+    def get_progress(self):
+        ''' Return the total progress, adding total done and total available.
+        (assumes that each submodule uses the same "units" for progress.)
+        '''
+        # TODO: Cache progress or children array?
+        children = self.get_children()
+        progresses = [child.get_progress() for child in children]
+        progress = reduce(Progress.add_counts, progresses)
+        return progress
+
     def handle_ajax(self, dispatch, get):		# TODO: bounds checking
         ''' get = request.POST instance '''
         if dispatch=='goto_position':
@@ -53,10 +67,15 @@ class Module(XModule):
         titles = ["\n".join([i.get("name").strip() for i in e.iter() if i.get("name") is not None]) \
                        for e in self.xmltree]
 
+        children = self.get_children()
+        progresses = [child.get_progress() for child in children]
+        
         self.contents = self.rendered_children()
 
-        for contents, title in zip(self.contents, titles):
+        for contents, title, progress in zip(self.contents, titles, progresses):
             contents['title'] = title
+            contents['progress_str'] = str(progress) if progress is not None else ""
+            contents['progress_stat'] = progress.ternary_str() if progress is not None else ""
 
         for (content, element_class) in zip(self.contents, child_classes):
             new_class = 'other'
@@ -68,16 +87,17 @@ class Module(XModule):
         # Split </script> tags -- browsers handle this as end
         # of script, even if it occurs mid-string. Do this after json.dumps()ing
         # so that we can be sure of the quotations being used
-        params={'items':json.dumps(self.contents).replace('</script>', '<"+"/script>'),
-                'id':self.item_id,
+        params={'items': json.dumps(self.contents).replace('</script>', '<"+"/script>'),
+                'id': self.item_id,
                 'position': self.position,
-                'titles':titles,
-                'tag':self.xmltree.tag}
+                'titles': titles,
+                'tag': self.xmltree.tag}
 
         if self.xmltree.tag in ['sequential', 'videosequence']:
             self.content = self.system.render_template('seq_module.html', params)
         if self.xmltree.tag == 'tab':
             self.content = self.system.render_template('tab_module.html', params)
+        log.debug("rendered content: %s", content)
         self.rendered = True
 
     def __init__(self, system, xml, item_id, state=None):
diff --git a/common/lib/xmodule/vertical_module.py b/common/lib/xmodule/vertical_module.py
index 7eb6dda0b8..b3feec8bae 100644
--- a/common/lib/xmodule/vertical_module.py
+++ b/common/lib/xmodule/vertical_module.py
@@ -1,12 +1,14 @@
 import json
 
 from x_module import XModule, XModuleDescriptor
+from xmodule.progress import Progress
 from lxml import etree
 
 class ModuleDescriptor(XModuleDescriptor):
     pass
 
 class Module(XModule):
+    ''' Layout module for laying out submodules vertically.'''
     id_attribute = 'id'
 
     def get_state(self):
@@ -21,6 +23,13 @@ class Module(XModule):
             'items': self.contents
         })
 
+    def get_progress(self):
+        # TODO: Cache progress or children array?
+        children = self.get_children()
+        progresses = [child.get_progress() for child in children]
+        progress = reduce(Progress.add_counts, progresses)
+        return progress
+
     def __init__(self, system, xml, item_id, state=None):
         XModule.__init__(self, system, xml, item_id, state)
         xmltree=etree.fromstring(xml)
diff --git a/common/lib/xmodule/x_module.py b/common/lib/xmodule/x_module.py
index 3a5bd05286..043a830500 100644
--- a/common/lib/xmodule/x_module.py
+++ b/common/lib/xmodule/x_module.py
@@ -59,6 +59,13 @@ class XModule(object):
         else: 
             raise "We should iterate through children and find a default name"
 
+    def get_children(self):
+        '''
+        Return module instances for all the children of this module.
+        '''
+        children = [self.module_from_xml(e) for e in self.__xmltree]
+        return children            
+
     def rendered_children(self):
         '''
         Render all children. 
@@ -92,6 +99,7 @@ class XModule(object):
             self.tracker = system.track_function
             self.filestore = system.filestore
             self.render_function = system.render_function
+            self.module_from_xml = system.module_from_xml
             self.DEBUG = system.DEBUG
         self.system = system
 
diff --git a/lms/djangoapps/courseware/grades.py b/lms/djangoapps/courseware/grades.py
index 354cf5991f..4a11ec2d51 100644
--- a/lms/djangoapps/courseware/grades.py
+++ b/lms/djangoapps/courseware/grades.py
@@ -174,6 +174,8 @@ def get_score(user, problem, cache, coursename=None):
     else:
         ## HACK 1: We shouldn't specifically reference capa_module
         ## HACK 2: Backwards-compatibility: This should be written when a grade is saved, and removed from the system
+        # TODO: These are no longer correct params for I4xSystem -- figure out what this code
+        # does, clean it up.
         from module_render import I4xSystem
         system = I4xSystem(None, None, None, coursename=coursename)
         total=float(xmodule.capa_module.Module(system, etree.tostring(problem), "id").max_score())
diff --git a/lms/djangoapps/courseware/module_render.py b/lms/djangoapps/courseware/module_render.py
index af5fec6b85..9b5e7e4940 100644
--- a/lms/djangoapps/courseware/module_render.py
+++ b/lms/djangoapps/courseware/module_render.py
@@ -34,7 +34,8 @@ class I4xSystem(object):
     and user, or other environment-specific info.
     '''
     def __init__(self, ajax_url, track_function, render_function,
-                 render_template, request=None, filestore=None):
+                 module_from_xml, render_template, request=None,
+                 filestore=None):
         '''
         Create a closure around the system environment.
 
@@ -43,6 +44,8 @@ class I4xSystem(object):
                          or otherwise tracking the event.
                          TODO: Not used, and has inconsistent args in different
                          files.  Update or remove.
+        module_from_xml - function that takes (module_xml) and returns a corresponding
+                          module instance object.
         render_function - function that takes (module_xml) and renders it,
                           returning a dictionary with a context for rendering the
                           module to html.  Dictionary will contain keys 'content'
@@ -62,6 +65,7 @@ class I4xSystem(object):
             if settings.DEBUG:
                 log.info("[courseware.module_render.I4xSystem] filestore path = %s",
                          filestore)
+        self.module_from_xml = module_from_xml
         self.render_function = render_function
         self.render_template = render_template
         self.exception404 = Http404
@@ -127,6 +131,18 @@ def grade_histogram(module_id):
         return []
     return grades
 
+
+def make_module_from_xml_fn(user, request, student_module_cache, position):
+    '''Create the make_from_xml() function'''
+    def module_from_xml(xml):
+        '''Modules need a way to convert xml to instance objects.
+        Pass the rest of the context through.'''
+        (instance, sm, module_type) = get_module(
+            user, request, xml, student_module_cache, position)
+        return instance
+    return module_from_xml
+
+
 def get_module(user, request, module_xml, student_module_cache, position=None):
     ''' Get an instance of the xmodule class corresponding to module_xml,
     setting the state based on an existing StudentModule, or creating one if none
@@ -165,6 +181,9 @@ def get_module(user, request, module_xml, student_module_cache, position=None):
     # Setup system context for module instance
     ajax_url = settings.MITX_ROOT_URL + '/modx/' + module_type + '/' + module_id + '/'
 
+    module_from_xml = make_module_from_xml_fn(
+        user, request, student_module_cache, position)
+    
     system = I4xSystem(track_function = make_track_function(request), 
                        render_function = lambda xml: render_x_module(
                            user, request, xml, student_module_cache, position),
@@ -172,6 +191,7 @@ def get_module(user, request, module_xml, student_module_cache, position=None):
                        ajax_url = ajax_url,
                        request = request,
                        filestore = OSFS(data_root),
+                       module_from_xml = module_from_xml,
                        )
     # pass position specified in URL to module through I4xSystem
     system.set('position', position) 
@@ -295,9 +315,17 @@ def modx_dispatch(request, module=None, dispatch=None, id=None):
             response = HttpResponse(json.dumps({'success': error_msg}))
         return response
 
+    # TODO: This doesn't have a cache of child student modules.  Just
+    # passing the current one.  If ajax calls end up needing children,
+    # this won't work (but fixing it may cause performance issues...)
+    # Figure out :)
+    module_from_xml = make_module_from_xml_fn(
+        request.user, request, [s], None)
+
     # Create the module
     system = I4xSystem(track_function = make_track_function(request), 
-                       render_function = None, 
+                       render_function = None,
+                       module_from_xml = module_from_xml,
                        render_template = render_to_string,
                        ajax_url = ajax_url,
                        request = request,
@@ -316,7 +344,11 @@ def modx_dispatch(request, module=None, dispatch=None, id=None):
         return response
 
     # Let the module handle the AJAX
-    ajax_return = instance.handle_ajax(dispatch, request.POST)
+    try:
+        ajax_return = instance.handle_ajax(dispatch, request.POST)
+    except:
+        log.exception("error processing ajax call")
+        raise
 
     # Save the state back to the database
     s.state = instance.get_state()
diff --git a/lms/static/coffee/src/modules/problem.coffee b/lms/static/coffee/src/modules/problem.coffee
index aad41f23d4..1b254d5d3f 100644
--- a/lms/static/coffee/src/modules/problem.coffee
+++ b/lms/static/coffee/src/modules/problem.coffee
@@ -17,12 +17,20 @@ class @Problem
     @$('section.action input.save').click @save
     @$('input.math').keyup(@refreshMath).each(@refreshMath)
 
+  update_progress: (response) =>
+    if response.progress_changed
+        @element.attr progress: response.progress
+        @element.trigger('progressChanged')
+
   render: (content) ->
     if content
       @element.html(content)
       @bind()
     else
-      @element.load @content_url, @bind
+      $.postWithPrefix "/modx/problem/#{@id}/problem_get", '', (response) =>
+        @element.html(response.html)
+        @bind()
+      
 
   check: =>
     Logger.log 'problem_check', @answers
@@ -30,19 +38,22 @@ class @Problem
       switch response.success
         when 'incorrect', 'correct'
           @render(response.contents)
+          @update_progress response
         else
           alert(response.success)
 
   reset: =>
     Logger.log 'problem_reset', @answers
-    $.postWithPrefix "/modx/problem/#{@id}/problem_reset", id: @id, (content) =>
-      @render(content)
+    $.postWithPrefix "/modx/problem/#{@id}/problem_reset", id: @id, (response) =>
+        @render(response.html)
+        @update_progress response
 
   show: =>
     if !@element.hasClass 'showed'
       Logger.log 'problem_show', problem: @id
       $.postWithPrefix "/modx/problem/#{@id}/problem_show", (response) =>
-        $.each response, (key, value) =>
+        answers = response.answers
+        $.each answers, (key, value) =>
           if $.isArray(value)
             for choice in value
               @$("label[for='input_#{key}_#{choice}']").attr correct_answer: 'true'
@@ -51,6 +62,7 @@ class @Problem
         MathJax.Hub.Queue ["Typeset", MathJax.Hub]
         @$('.show').val 'Hide Answer'
         @element.addClass 'showed'
+        @update_progress response
     else
       @$('[id^=answer_], [id^=solution_]').text ''
       @$('[correct_answer]').attr correct_answer: null
@@ -62,6 +74,7 @@ class @Problem
     $.postWithPrefix "/modx/problem/#{@id}/problem_save", @answers, (response) =>
       if response.success
         alert 'Saved'
+      @update_progress response
 
   refreshMath: (event, element) =>
     element = event.target unless element
diff --git a/lms/static/coffee/src/modules/sequence.coffee b/lms/static/coffee/src/modules/sequence.coffee
index 463bf419fc..72a1c82ab6 100644
--- a/lms/static/coffee/src/modules/sequence.coffee
+++ b/lms/static/coffee/src/modules/sequence.coffee
@@ -2,6 +2,7 @@ class @Sequence
   constructor: (@id, @elements, @tag, position) ->
     @element = $("#sequence_#{@id}")
     @buildNavigation()
+    @initProgress()
     @bind()
     @render position
 
@@ -11,11 +12,52 @@ class @Sequence
   bind: ->
     @$('#sequence-list a').click @goto
 
+  initProgress: ->
+    @progressTable = {}  # "#problem_#{id}" -> progress
+
+
+  hookUpProgressEvent: ->
+    $('.problems-wrapper').bind 'progressChanged', @updateProgress
+
+  mergeProgress: (p1, p2) ->
+    if p1 == "done" and p2 == "done"
+      return "done"
+    # not done, so if any progress on either, in_progress
+    w1 = p1 == "done" or p1 == "in_progress"
+    w2 = p2 == "done" or p2 == "in_progress"
+    if w1 or w2
+      return "in_progress"
+
+    return "none"
+
+  updateProgress: =>
+    new_progress = "none"
+    _this = this
+    $('.problems-wrapper').each (index) ->
+      progress = $(this).attr 'progress'
+      new_progress = _this.mergeProgress progress, new_progress
+
+    @progressTable[@position] = new_progress
+    @setProgress(new_progress, @link_for(@position))
+
+  setProgress: (progress, element) ->
+      element.removeClass('progress-none')
+             .removeClass('progress-some')
+             .removeClass('progress-done')
+      switch progress
+        when 'none' then element.addClass('progress-none')
+        when 'in_progress' then element.addClass('progress-some')
+        when 'done' then element.addClass('progress-done')
+  
   buildNavigation: ->
     $.each @elements, (index, item) =>
       link = $('<a>').attr class: "seq_#{item.type}_inactive", 'data-element': index + 1
       title = $('<p>').html(item.title)
+      # TODO: add item.progress_str either to the title or somewhere else.
+      # Make sure it gets updated after ajax calls
       list_item = $('<li>').append(link.append(title))
+      @setProgress item.progress_stat, link
+        
       @$('#sequence-list').append list_item
 
   toggleArrows: =>
@@ -36,13 +78,14 @@ class @Sequence
       if @position != undefined
         @mark_visited @position
         $.postWithPrefix "/modx/#{@tag}/#{@id}/goto_position", position: new_position
-
+        
       @mark_active new_position
       @$('#seq_content').html @elements[new_position - 1].content
 
       MathJax.Hub.Queue(["Typeset", MathJax.Hub])
       @position = new_position
       @toggleArrows()
+      @hookUpProgressEvent()
       @element.trigger 'contentChanged'
 
   goto: (event) =>
@@ -67,7 +110,17 @@ class @Sequence
     @$("#sequence-list a[data-element=#{position}]")
 
   mark_visited: (position) ->
-    @link_for(position).attr class: "seq_#{@elements[position - 1].type}_visited"
+    # Don't overwrite class attribute to avoid changing Progress class
+    type = @elements[position - 1].type
+    element = @link_for(position)
+    element.removeClass("seq_#{type}_inactive")
+    .removeClass("seq_#{type}_active")
+    .addClass("seq_#{type}_visited")
 
   mark_active: (position) ->
-    @link_for(position).attr class: "seq_#{@elements[position - 1].type}_active"
+    # Don't overwrite class attribute to avoid changing Progress class
+    type = @elements[position - 1].type
+    element = @link_for(position)
+    element.removeClass("seq_#{type}_inactive")
+    .removeClass("seq_#{type}_visited")
+    .addClass("seq_#{type}_active")