~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

# App: subjects

# Author: Matt Giuca

# Date: 29/2/2008

# This is an IVLE application.

# A sample / testing application for IVLE.

import os

import urllib

import cgi

from storm.locals import Desc

from genshi.filters import HTMLFormFiller

import formencode

from ivle.webapp.base.xhtml import XHTMLView

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

from ivle.webapp.errors import NotFound

from ivle.database import Subject, Semester, Offering, Enrolment, User

from ivle import util

class SubjectsView(XHTMLView):

    '''The view of the list of subjects.'''

    template = 'subjects.html'

    tab = 'subjects'

    def authorize(self, req):

        return req.user is not None

    def populate(self, req, ctx):

        ctx['user'] = req.user

        ctx['semesters'] = []

        for semester in req.store.find(Semester).order_by(Desc(Semester.year),

                                                     Desc(Semester.semester)):

            enrolments = semester.enrolments.find(user=req.user)

            if enrolments.count():

                ctx['semesters'].append((semester, enrolments))

class UserValidator(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):

        user = User.get_by_login(state.store, value)

        if user:

            return user

        else:

            raise formencode.Invalid('User does not exist', value, state)

class NoEnrolmentValidator(formencode.FancyValidator):

    """A FormEncode validator that ensures absence of an enrolment.

    The state must have an 'offering' attribute.

    """

    def _to_python(self, value, state):

        if state.offering.get_enrolment(value):

            raise formencode.Invalid('User already enrolled', value, state)

        return value

class EnrolSchema(formencode.Schema):

    user = formencode.All(NoEnrolmentValidator(), UserValidator())

class EnrolView(XHTMLView):

    """A form to enrol a user in an offering."""

    template = 'enrol.html'

    tab = 'subjects'

    permission = 'edit'

    def __init__(self, req, subject, year, semester):

        """Find the given offering by subject, year and semester."""

        self.context = req.store.find(Offering,

            Offering.subject_id == Subject.id,

            Subject.short_name == subject,

            Offering.semester_id == Semester.id,

            Semester.year == year,

            Semester.semester == semester).one()

        if not self.context:

            raise NotFound()

    def filter(self, stream, ctx):

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

    def populate(self, req, ctx):

        if req.method == 'POST':

            data = dict(req.get_fieldstorage())

            try:

                validator = EnrolSchema()

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

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

                self.context.enrol(data['user'])

                req.store.commit()

                req.throw_redirect(req.uri)

            except formencode.Invalid, e:

                errors = e.unpack_errors()

        else:

            data = {}

            errors = {}

        ctx['data'] = data or {}

        ctx['offering'] = self.context

        ctx['errors'] = errors

class Plugin(ViewPlugin, MediaPlugin):

    urls = [

        ('subjects/', SubjectsView),

        ('subjects/:subject/:year/:semester/+enrolments/+new', EnrolView),

    ]

    tabs = [

        ('subjects', 'Subjects',

         'View subject content and complete worksheets',

         'subjects.png', 'subjects', 5)

    ]

    media = 'subject-media'