~azzar1/unity/add-show-desktop-key

# IVLE

# Copyright (C) 2007-2008 The University of Melbourne

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

# Author: Matt Giuca, Will Grant

'''Tutorial/worksheet/exercise application.

Displays tutorial content with editable exercises, allowing students to test

and submit their solutions to exercises and have them auto-tested.

'''

import os

import urllib

import re

import mimetypes

from datetime import datetime

from xml.dom import minidom

import formencode

import formencode.validators

import genshi

import genshi.input

from genshi.filters import HTMLFormFiller

import docutils.utils

import ivle.database

from ivle.database import Subject, Offering, Semester, Exercise, \

                          ExerciseSave, WorksheetExercise, ExerciseAttempt

from ivle.database import Worksheet

import ivle.worksheet.utils

from ivle.webapp import ApplicationRoot

from ivle.webapp.base.forms import URLNameValidator

from ivle.webapp.base.views import BaseView

from ivle.webapp.base.xhtml import XHTMLView

from ivle.webapp.base.plugins import ViewPlugin, MediaPlugin

from ivle.webapp.media import media_url

from ivle.webapp.errors import NotFound

from ivle.webapp.tutorial.service import (AttemptsRESTView, AttemptRESTView,

            WorksheetExerciseRESTView, WorksheetsRESTView)

from ivle.webapp.tutorial.exercise_service import ExercisesRESTView, \

                                                  ExerciseRESTView

from ivle.webapp.tutorial.publishing import (root_to_exercise, exercise_url,

            offering_to_worksheet, worksheet_url,

            worksheet_to_worksheetexercise, worksheetexercise_url,

            ExerciseAttempts, worksheetexercise_to_exerciseattempts,

            exerciseattempts_url, exerciseattempts_to_attempt,

            exerciseattempt_url)

from ivle.webapp.tutorial.breadcrumbs import (ExerciseBreadcrumb,

            WorksheetBreadcrumb)

from ivle.webapp.tutorial.media import (SubjectMediaFile, SubjectMediaView,

    subject_to_media)

from ivle.webapp.tutorial.marks import (WorksheetsMarksView,

            WorksheetsMarksCSVView)

class WorksheetView(XHTMLView):

    '''The view of a worksheet with exercises.'''

    template = 'templates/worksheet.html'

    tab = 'subjects'

    permission = 'view'

    def populate(self, req, ctx):

        self.plugin_scripts[Plugin] = ['tutorial.js']

        self.plugin_styles[Plugin] = ['tutorial.css', 'worksheet.css']

        if not self.context:

            raise NotFound()

        ctx['subject'] = self.context.offering.subject

        ctx['worksheet'] = self.context

        ctx['semester'] = self.context.offering.semester.url_name

        ctx['year'] = self.context.offering.semester.year

        ctx['worksheetstream'] = genshi.Stream(list(genshi.XML(self.context.data_xhtml)))

        ctx['user'] = req.user

        ctx['config'] = req.config

        ctx['show_exercise_stats'] = \

            'edit' in self.context.get_permissions(req.user,

                                                   req.config)

        generate_worksheet_data(ctx, req, self._loader, self.context)

        ctx['worksheetstream'] = add_exercises(ctx['worksheetstream'], ctx, req)

def get_worksheets(subjectfile):

    '''Given a subject stream, get all the worksheets and put them in ctx'''

    worksheets = []

    for kind, data, pos in subjectfile:

        if kind is genshi.core.START:

            if data[0] == 'worksheet':

                worksheetid = ''

                worksheetname = ''

                worksheetasses = False

                for attr in data[1]:

                    if attr[0] == 'id':

                        worksheetid = attr[1]

                    elif attr[0] == 'name':

                        worksheetname = attr[1]

                    elif attr[0] == 'assessable':

                        worksheetasses = attr[1] == 'true'

                worksheets.append(Worksheet(worksheetid, worksheetname, \

                                                            worksheetasses))

    return worksheets

# This generator adds in the exercises as they are required. This is returned.

def add_exercises(stream, ctx, req):

    """A filter which adds exercises into the stream."""

    exid = 0

    for kind, data, pos in stream:

        if kind is genshi.core.START:

            # Remove the worksheet tags, as they are not xhtml valid.

            if data[0] == 'worksheet':

                continue

            # If we have an exercise node, replace it with the content of the

            # exercise. Note that we only consider exercises with a

            # 'src' attribute, the same condition that generate_worksheet_data

            # uses to create ctx['exercises'].

            elif data[0] == 'exercise' and 'src' in dict(data[1]):

                # XXX: Note that we presume ctx['exercises'] has a correct list

                #      of exercises. If it doesn't, something has gone wrong.

                new_stream = ctx['exercises'][exid]['stream']

                exid += 1

                for item in new_stream:

                    yield item

            else:

                yield kind, data, pos

        # Remove the end tags for exercises and worksheets

        elif kind is genshi.core.END:

            if data == 'exercise':

                continue

            elif data == 'worksheet':

                continue

            else:

                yield kind, data, pos

        else:

            yield kind, data, pos

# This function runs through the worksheet, to get data on the exercises to

# build a Table of Contents, as well as fill in details in ctx

def generate_worksheet_data(ctx, req, loader, worksheet):

    """Runs through the worksheetstream, generating the exericises"""

    ctx['exercises'] = []

    ctx['exerciselist'] = []

    for kind, data, pos in ctx['worksheetstream']:

        if kind is genshi.core.START:

            if data[0] == 'exercise':

                src = ""

                optional = False

                for attr in data[1]:

                    if attr[0] == 'src':

                        src = attr[1]

                    if attr[0] == 'optional':

                        optional = attr[1] == 'true'

                # Each item in toc is of type (name, complete, stream)

                if src != "":

                    ctx['exercises'].append(

                        present_exercise(req, loader, src, worksheet))

                    ctx['exerciselist'].append((src, optional))

            elif data[0] == 'worksheet':

                ctx['worksheetname'] = 'bob'

                for attr in data[1]:

                    if attr[0] == 'name':

                        ctx['worksheetname'] = attr[1]

def innerXML(elem):

    """Given an element, returns its children as XML strings concatenated

    together."""

    s = ""

    for child in elem.childNodes:

        s += child.toxml()

    return s

def getTextData(element):

    """ Get the text and cdata inside an element

    Leading and trailing whitespace are stripped

    """

    data = ''

    for child in element.childNodes:

        if child.nodeType == child.CDATA_SECTION_NODE:

            data += child.data

        elif child.nodeType == child.TEXT_NODE:

            data += child.data

        elif child.nodeType == child.ELEMENT_NODE:

            data += getTextData(child)

    return data.strip()

def present_exercise(req, loader, identifier, worksheet=None):

    """Render an HTML representation of an exercise.

    identifier: The exercise identifier (URL name).

    worksheet: An optional worksheet from which to retrieve saved results.

               If omitted, a clean exercise will be presented.

    """

    # Exercise-specific context is used here, as we already have all the data

    # we need

    curctx = genshi.template.Context()

    curctx['worksheet'] = worksheet

    if worksheet is not None:

        worksheet_exercise = req.store.find(WorksheetExercise,

            WorksheetExercise.worksheet_id == worksheet.id,

            WorksheetExercise.exercise_id == identifier).one()

        if worksheet_exercise is None:

            raise NotFound()

    # Retrieve the exercise details from the database

    exercise = req.store.find(Exercise, 

        Exercise.id == identifier).one()

    if exercise is None:

        raise ivle.worksheet.utils.ExerciseNotFound(identifier)

    # Read exercise file and present the exercise

    # Note: We do not use the testing framework because it does a lot more

    # work than we need. We just need to get the exercise name and a few other

    # fields from the XML.

    curctx['req'] = req

    curctx['exercise'] = exercise

    curctx['description'] = None

    curctx['error'] = None

    try:

        desc_xhtml = exercise.description_xhtml

        if desc_xhtml:

            curctx['description'] = genshi.XML(desc_xhtml)

        else:

            curctx['description'] = None

    except docutils.utils.SystemMessage, e:

        curctx['error'] = "Error processing reStructuredText: '%s'" % str(e)

    # If the user has already saved some text for this problem, or submitted

    # an attempt, then use that text instead of the supplied "partial".

    # Get exercise stored text will return a save, or the most recent attempt,

    # whichever is more recent

    if worksheet is not None:

        save = ivle.worksheet.utils.get_exercise_stored_text(

                            req.store, req.user, worksheet_exercise)

        # Also get the number of attempts taken and whether this is complete.

        complete, curctx['attempts'] = \

                ivle.worksheet.utils.get_exercise_status(req.store, req.user, 

                                                         worksheet_exercise)

        if save is not None:

            curctx['exercisesave'] = save.text

        else:

            curctx['exercisesave']= exercise.partial

        curctx['complete'] = 'Complete' if complete else 'Incomplete'

        curctx['complete_class'] = curctx['complete'].lower()

    else:

        curctx['exercisesave'] = exercise.partial

        curctx['complete'] = 'Incomplete'

        curctx['complete_class'] = curctx['complete'].lower()

        curctx['attempts'] = 0

    #Save the exercise details to the Table of Contents

    tmpl = loader.load(os.path.join(os.path.dirname(__file__),

        "templates/exercise_fragment.html"))

    ex_stream = tmpl.generate(curctx)

    # Store exercise statistics

    if (worksheet is not None and

        'edit' in worksheet.get_permissions(req.user, req.config)):

        exercise_stats = ivle.worksheet.utils.get_exercise_statistics(

            req.store, worksheet_exercise)

    else:

        exercise_stats = None

    return {'name': exercise.name,

            'complete': curctx['complete_class'],

            'stream': ex_stream,

            'exid': exercise.id,

            'stats': exercise_stats}

# The first element is the default format

WORKSHEET_FORMATS = (('reStructuredText', 'rst'), ('XHTML (legacy)', 'xml'))

class WorksheetFormatValidator(formencode.FancyValidator):

    """A FormEncode validator that turns a username into a user.

    The state must have a 'store' attribute, which is the Storm store

    to use."""

    def _to_python(self, value, state):

        if value not in [x for (_,x) in WORKSHEET_FORMATS]:

            raise formencode.Invalid('Unsupported format', value, state)

        return value

class WorksheetIdentifierUniquenessValidator(formencode.FancyValidator):

    """A FormEncode validator that checks that a worksheet name is unused.

    The worksheet referenced by state.existing_worksheet is permitted

    to hold that name. If any other object holds it, the input is rejected.

    The state must have an 'offering' attribute.

    """

    def __init__(self, matching=None):

        self.matching = matching

    def _to_python(self, value, state):

        if (state.store.find(

            Worksheet, offering=state.offering,

            identifier=value).one() not in (None, state.existing_worksheet)):

            raise formencode.Invalid(

                'Short name already taken', value, state)

        return value

class WorksheetSchema(formencode.Schema):

    identifier = formencode.All(

        WorksheetIdentifierUniquenessValidator(),

        URLNameValidator(not_empty=True))

    name = formencode.validators.UnicodeString(not_empty=True)

    assessable = formencode.validators.StringBoolean(if_missing=False)

    published = formencode.validators.StringBoolean(if_missing=False)

    data = formencode.validators.UnicodeString(not_empty=True)

    format = formencode.All(

        WorksheetFormatValidator(),

        formencode.validators.UnicodeString(not_empty=True))

class WorksheetFormView(XHTMLView):

    """An abstract form for a worksheet in an offering."""

    def filter(self, stream, ctx):

        return stream | HTMLFormFiller(data=ctx['data'])

    def populate_state(self, state):

        state.existing_worksheet = None

    def populate(self, req, ctx):

        if req.method == 'POST':

            data = dict(req.get_fieldstorage())

            try:

                validator = WorksheetSchema()

                req.offering = self.offering # XXX: Getting into state.

                self.populate_state(req)

                data = validator.to_python(data, state=req)

                worksheet = self.get_worksheet_object(req, data)

                ivle.worksheet.utils.update_exerciselist(worksheet)

                req.store.commit()

                req.throw_redirect(req.publisher.generate(worksheet))

            except formencode.Invalid, e:

                errors = e.unpack_errors()

            except genshi.input.ParseError, e:

                errors = {'data': 'Could not parse XML: %s' % e.message}

            except ivle.worksheet.utils.ExerciseNotFound, e:

                errors = {'data': 'Could not find exercise "%s"' % e.message}

            except docutils.utils.SystemMessage, e:

                errors = {'data': 'Could not parse reStructuredText: %s'%(

                        e.message)}

        else:

            data = self.get_default_data(req)

            errors = {}

        if errors:

            req.store.rollback()

        ctx['data'] = data or {}

        ctx['offering'] = self.context

        ctx['errors'] = errors

        # If all of the fields validated, set the global form error.

        if isinstance(errors, basestring):

            ctx['error_value'] = errors

        ctx['formats'] = WORKSHEET_FORMATS

class WorksheetAddView(WorksheetFormView):

    """An form to create a worksheet in an offering."""

    template = 'templates/worksheet_add.html'

    permission = 'edit_worksheets'

    tab = 'subjects'

    @property

    def offering(self):

        return self.context

    def get_default_data(self, req):

        return {}

    def get_worksheet_object(self, req, data):

        new_worksheet = Worksheet()

        new_worksheet.seq_no = self.context.worksheets.count()

        # Setting new_worksheet.offering implicitly adds new_worksheet,

        # hence worksheets.count MUST be called above it

        new_worksheet.offering = self.context

        new_worksheet.identifier = data['identifier']

        new_worksheet.name = data['name']

        new_worksheet.assessable = data['assessable']

        new_worksheet.published = data['published']

        new_worksheet.set_data(data['data'])

        new_worksheet.format = data['format']

        req.store.add(new_worksheet)

        return new_worksheet

class WorksheetEditView(WorksheetFormView):

    """An form to alter a worksheet in an offering."""

    template = 'templates/worksheet_edit.html'

    permission = 'edit'

    tab = 'subjects'

    def populate_state(self, state):

        state.existing_worksheet = self.context

    @property

    def offering(self):

        return self.context.offering

    def get_default_data(self, req):

        return {

            'identifier': self.context.identifier,

            'name': self.context.name,

            'assessable': self.context.assessable,

            'published': self.context.published,

            'data': self.context.data,

            'format': self.context.format

            }

    def get_worksheet_object(self, req, data):

        self.context.identifier = data['identifier']

        self.context.name = data['name']

        self.context.assessable = data['assessable']

        self.context.published = data['published']

        self.context.set_data(data['data'])

        self.context.format = data['format']

        return self.context

class WorksheetsEditView(XHTMLView):

    """View for arranging worksheets."""

    permission = 'edit_worksheets'

    template = 'templates/worksheets_edit.html'

    tab = 'subjects'

    def populate(self, req, ctx):

        self.plugin_styles[Plugin] = ['tutorial_admin.css']

        self.plugin_scripts[Plugin] = ['tutorial_admin.js']

        ctx['subject'] = self.context.subject

        ctx['year'] = self.context.semester.year

        ctx['semester'] = self.context.semester.url_name

        ctx['worksheets'] = self.context.worksheets

        ctx['mediapath'] = media_url(req, Plugin, 'images/')

class ExerciseView(XHTMLView):

    """View of an exercise.

    Primarily to preview and test an exercise without adding it to a

    worksheet for all to see.

    """

    permission = 'edit'

    template = 'templates/exercise.html'

    tab = 'subjects'

    def populate(self, req, ctx):

        self.plugin_scripts[Plugin] = ['tutorial.js']

        self.plugin_styles[Plugin] = ['tutorial.css']

        ctx['req'] = req

        ctx['mediapath'] = media_url(req, Plugin, 'images/')

        ctx['exercise'] = self.context

        ctx['exercise_fragment'] = present_exercise(

            req, self._loader, self.context.id)['stream']

        ctx['ExerciseEditView'] = ExerciseEditView

        ctx['ExerciseDeleteView'] = ExerciseDeleteView

class ExerciseEditView(XHTMLView):

    """View for editing a worksheet."""

    permission = 'edit'

    template = 'templates/exercise_edit.html'

    breadcrumb_text = 'Edit'

    tab = 'subjects'

    def populate(self, req, ctx):

        self.plugin_styles[Plugin] = ['exercise_admin.css']

        self.plugin_scripts[Plugin] = ['exercise_admin.js']

        ctx['mediapath'] = media_url(req, Plugin, 'images/')

        ctx['exercise'] = self.context

        #XXX: These should come from somewhere else

        ctx['var_types'] = {

            'var': 'variable',

            'arg': 'function argument',

            'exception': 'exception',

            }

        ctx['part_types'] = {

            'stdout': 'standard output',

            'stderr': 'standard error',

            'result': 'function result',

            'exception': 'raised exception',

            'code': 'code',

            }

        ctx['test_types'] = {'norm': 'normalisation', 'check': 'comparison'}

class ExerciseDeleteView(XHTMLView):

    """View for confirming the deletion of an exercise."""

    permission = 'edit'

    template = 'templates/exercise_delete.html'

    tab = 'subjects'

    def populate(self, req, ctx):

        # If post, delete the exercise, or display a message explaining that

        # the exercise cannot be deleted

        if req.method == 'POST':

            try:

                self.context.delete()

                self.template = 'templates/exercise_deleted.html'

            except Exception:

                self.template = 'templates/exercise_undeletable.html'

        # If get, display a delete confirmation page

        else:

            if self.context.worksheet_exercises.count() != 0:

                self.template = 'templates/exercise_undeletable.html'

        # Variables for the template

        ctx['exercise'] = self.context

class ExerciseAddView(XHTMLView):

    """View for creating a new exercise."""

    permission = 'edit'

    template = 'templates/exercise_add.html'

    tab = 'subjects'

    def authorize(self, req):

        return ('edit' in

            ivle.database.Exercise.global_permissions(req.user, req.config))

    def populate(self, req, ctx):

        self.plugin_scripts[Plugin] = ['exercise_admin.js']

class ExercisesView(XHTMLView):

    """View for seeing the list of all exercises"""

    permission = 'edit'

    template = 'templates/exercises.html'

    breadcrumb_text = 'Exercises'

    tab = 'subjects'

    def authorize(self, req):

        return ('edit' in

            ivle.database.Exercise.global_permissions(req.user, req.config))

    def populate(self, req, ctx):

        self.plugin_styles[Plugin] = ['exercise_admin.css']

        ctx['req'] = req

        ctx['mediapath'] = media_url(req, Plugin, 'images/')

        ctx['exercises'] = req.store.find(Exercise).order_by(Exercise.id)

class Plugin(ViewPlugin, MediaPlugin):

    forward_routes = (root_to_exercise, offering_to_worksheet,

        worksheet_to_worksheetexercise, worksheetexercise_to_exerciseattempts,

        exerciseattempts_to_attempt, subject_to_media)

    reverse_routes = (exercise_url, worksheet_url, worksheetexercise_url,

        exerciseattempts_url, exerciseattempt_url)

    breadcrumbs = {Exercise: ExerciseBreadcrumb,

                   Worksheet: WorksheetBreadcrumb

                  }

    views = [(Offering, ('+worksheets', '+new'), WorksheetAddView),

             (Offering, ('+worksheets', '+edit'), WorksheetsEditView),

             (Offering, ('+worksheets', '+marks', '+index'),

              WorksheetsMarksView),

             (Offering, ('+worksheets', '+marks', 'marks.csv'),

              WorksheetsMarksCSVView),

             (Worksheet, '+index', WorksheetView),

             (Worksheet, '+edit', WorksheetEditView),

             (ApplicationRoot, ('+exercises', '+index'), ExercisesView),

             (ApplicationRoot, ('+exercises', '+add'), ExerciseAddView),

             (Exercise, '+index', ExerciseView),

             (Exercise, '+edit', ExerciseEditView),

             (Exercise, '+delete', ExerciseDeleteView),

             (SubjectMediaFile, '+index', SubjectMediaView),

             (Offering, ('+worksheets', '+index'), WorksheetsRESTView, 'api'),

             (WorksheetExercise, '+index', WorksheetExerciseRESTView, 'api'),

             (ExerciseAttempts, '+index', AttemptsRESTView, 'api'),

             (ExerciseAttempt, '+index', AttemptRESTView, 'api'),