source: main/waeup.kofa/trunk/src/waeup/kofa/students/utils.py @ 9957

## $Id: utils.py 9957 2013-02-15 13:31:58Z henrik $
##
## Copyright (C) 2011 Uli Fouquet & Henrik Bettermann
## 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
##
"""General helper functions and utilities for the student section.
"""
import grok
from time import time
from reportlab.lib import colors
from reportlab.lib.units import cm
from reportlab.lib.pagesizes import A4
from reportlab.lib.styles import getSampleStyleSheet
from reportlab.platypus import Paragraph, Image, Table, Spacer
from zope.schema.interfaces import ConstraintNotSatisfied
from zope.component import getUtility, createObject
from zope.formlib.form import setUpEditWidgets
from zope.i18n import translate
from waeup.kofa.interfaces import (
    IExtFileStore, IKofaUtils, RETURNING, PAID, CLEARED,
    academic_sessions_vocab)
from waeup.kofa.interfaces import MessageFactory as _
from waeup.kofa.students.interfaces import IStudentsUtils
from waeup.kofa.browser.pdf import (
    ENTRY1_STYLE, format_html, NOTE_STYLE, HEADING_STYLE)
from waeup.kofa.browser.interfaces import IPDFCreator

SLIP_STYLE = [
    ('VALIGN',(0,0),(-1,-1),'TOP'),
    #('FONT', (0,0), (-1,-1), 'Helvetica', 11),
    ]

CONTENT_STYLE = [
    ('VALIGN',(0,0),(-1,-1),'TOP'),
    #('FONT', (0,0), (-1,-1), 'Helvetica', 8),
    #('TEXTCOLOR',(0,0),(-1,0),colors.white),
    #('BACKGROUND',(0,0),(-1,0),colors.black),
    ('INNERGRID', (0,0), (-1,-1), 0.25, colors.black),
    ('BOX', (0,0), (-1,-1), 1, colors.black),

    ]

FONT_SIZE = 10
FONT_COLOR = 'black'

def trans(text, lang):
    # shortcut
    return translate(text, 'waeup.kofa', target_language=lang)

def formatted_text(text, color=FONT_COLOR):
    """Turn `text`, `color` and `size` into an HTML snippet.

    The snippet is suitable for use with reportlab and generating PDFs.
    Wraps the `text` into a ``<font>`` tag with passed attributes.

    Also non-strings are converted. Raw strings are expected to be
    utf-8 encoded (usually the case for widgets etc.).

    Finally, a br tag is added if widgets contain div tags
    which are not supported by reportlab.

    The returned snippet is unicode type.
    """
    try:
        # In unit tests IKofaUtils has not been registered
        portal_language = getUtility(IKofaUtils).PORTAL_LANGUAGE
    except:
        portal_language = 'en'
    if not isinstance(text, unicode):
        if isinstance(text, basestring):
            text = text.decode('utf-8')
        else:
            text = unicode(text)
    if text == 'None':
        text = ''
    # Mainly for boolean values we need our customized
    # localisation of the zope domain
    text = translate(text, 'zope', target_language=portal_language)
    text = text.replace('</div>', '<br /></div>')
    tag1 = u'<font color="%s">' % (color)
    return tag1 + u'%s</font>' % text

def generate_student_id():
    students = grok.getSite()['students']
    new_id = students.unique_student_id
    return new_id

def set_up_widgets(view, ignore_request=False):
    view.adapters = {}
    view.widgets = setUpEditWidgets(
        view.form_fields, view.prefix, view.context, view.request,
        adapters=view.adapters, for_display=True,
        ignore_request=ignore_request
        )

def render_student_data(studentview):
    """Render student table for an existing frame.
    """
    width, height = A4
    set_up_widgets(studentview, ignore_request=True)
    data_left = []
    data_right = []
    style = getSampleStyleSheet()
    img = getUtility(IExtFileStore).getFileByContext(
        studentview.context, attr='passport.jpg')
    if img is None:
        from waeup.kofa.browser import DEFAULT_PASSPORT_IMAGE_PATH
        img = open(DEFAULT_PASSPORT_IMAGE_PATH, 'rb')
    doc_img = Image(img.name, width=4*cm, height=4*cm, kind='bound')
    data_left.append([doc_img])
    #data.append([Spacer(1, 12)])
    portal_language = getUtility(IKofaUtils).PORTAL_LANGUAGE

    f_label = _('Name:')
    f_label = Paragraph(f_label, ENTRY1_STYLE)
    f_text = formatted_text(studentview.context.display_fullname)
    f_text = Paragraph(f_text, ENTRY1_STYLE)
    data_right.append([f_label,f_text])

    for widget in studentview.widgets:
        if 'name' in widget.name:
            continue
        f_label = translate(
            widget.label.strip(), 'waeup.kofa',
            target_language=portal_language)
        f_label = Paragraph('%s:' % f_label, ENTRY1_STYLE)
        f_text = formatted_text(widget())
        f_text = Paragraph(f_text, ENTRY1_STYLE)
        data_right.append([f_label,f_text])

    if getattr(studentview.context, 'certcode', None):
        f_label = _('Study Course:')
        f_label = Paragraph(f_label, ENTRY1_STYLE)
        f_text = formatted_text(
            studentview.context['studycourse'].certificate.longtitle())
        f_text = Paragraph(f_text, ENTRY1_STYLE)
        data_right.append([f_label,f_text])

        f_label = _('Department:')
        f_label = Paragraph(f_label, ENTRY1_STYLE)
        f_text = formatted_text(
            studentview.context[
            'studycourse'].certificate.__parent__.__parent__.longtitle(),
            )
        f_text = Paragraph(f_text, ENTRY1_STYLE)
        data_right.append([f_label,f_text])

        f_label = _('Faculty:')
        f_label = Paragraph(f_label, ENTRY1_STYLE)
        f_text = formatted_text(
            studentview.context[
            'studycourse'].certificate.__parent__.__parent__.__parent__.longtitle(),
            )
        f_text = Paragraph(f_text, ENTRY1_STYLE)
        data_right.append([f_label,f_text])

        f_label = _('Entry Session: ')
        f_label = Paragraph(f_label, ENTRY1_STYLE)
        entry_session = studentview.context['studycourse'].entry_session
        entry_session = academic_sessions_vocab.getTerm(entry_session).title
        f_text = formatted_text(entry_session)
        f_text = Paragraph(f_text, ENTRY1_STYLE)
        data_right.append([f_label,f_text])

    table_left = Table(data_left,style=SLIP_STYLE)
    table_right = Table(data_right,style=SLIP_STYLE, colWidths=[5*cm, 6*cm])
    table = Table([[table_left, table_right],],style=SLIP_STYLE)
    return table

def render_table_data(tableheader,tabledata):
    """Render children table for an existing frame.
    """
    data = []
    #data.append([Spacer(1, 12)])
    line = []
    style = getSampleStyleSheet()
    for element in tableheader:
        field = '<strong>%s</strong>' % formatted_text(element[0])
        field = Paragraph(field, style["Normal"])
        line.append(field)
    data.append(line)
    for ticket in tabledata:
        line = []
        for element in tableheader:
              field = formatted_text(getattr(ticket,element[1],u' '))
              field = Paragraph(field, style["Normal"])
              line.append(field)
        data.append(line)
    table = Table(data,colWidths=[
        element[2]*cm for element in tableheader], style=CONTENT_STYLE)
    return table

def get_signature_table(signatures, lang='en'):
    """Return a list of one or more reportlab tables with signature fields.

    Each signature will get a date field.

    If more than three signatures have to be rendered, instead of a
    list with one table a list of tables with one signature field each
    will be returned.
    """
    style = getSampleStyleSheet()
    space_width = 0.4  # width in cm of space between signatures
    table_width = 16.0 # supposed width of signature table in cms
    # width of signature cells in cm...
    sig_col_width = table_width - ((len(signatures) - 1) * space_width)
    sig_col_width = sig_col_width / len(signatures)
    data = []
    col_widths = [] # widths of columns

    sig_style = [
        ('VALIGN',(0,-1),(-1,-1),'TOP'),
        #('FONT', (0,0), (-1,-1), 'Helvetica-BoldOblique', 12),
        ('BOTTOMPADDING', (0,0), (-1,0), 36),
        ('TOPPADDING', (0,-1), (-1,-1), 0),
        ]

    col_widths = [sig_col_width*cm, space_width*cm] * len(signatures)
    if len(signatures) == 1 or len(signatures) > 3:
        col_widths = [table_width*0.66*cm, table_width*0.34*cm]

    row = []
    if len(signatures) < 4:
        # draw several signature fields in a row
        for num, signature in enumerate(signatures):
            # draw a line above each signature cell (not: empty cells
            # in between)
            sig_style.append(
                ('LINEABOVE', (num*2,-1), (num*2, -1), 1, colors.black))
            row.append(Paragraph(trans(_('Date:'), lang), ENTRY1_STYLE))
            row.append('') # space col
        data.append(row[:-1])
        data.extend(([''],)*2) # insert 2 empty rows...
        row = []
        for signature in signatures:
            row.append(Paragraph(trans(signature, lang), ENTRY1_STYLE))
            row.append('')
        data.append(row[:-1])
    else:
        # Draw each signature field one under another (vertically)
        for num, signature in enumerate(signatures):
            line = len(data)
            sig_style.extend((
                ('TOPPADDING', (0, line), (-1, line), 32),
                ('BOTTOMPADDING', (0, line), (-1, line), 2),
                ('LINEABOVE', (0, line+1), (0, line+1), 1, colors.black),
                ('SPAN', (0, line+1), (1, line+1)),
                ))
            data.append(['', ''])
            row.append(Paragraph(trans(signature, lang), ENTRY1_STYLE))
            data.append(row)
            row = []
    table = Table(data, style=sig_style, repeatRows=len(data),
                  colWidths=col_widths)
    return table

def docs_as_flowables(view, lang='en'):
    """Create reportlab flowables out of scanned docs.
    """
    # XXX: fix circular import problem
    from waeup.kofa.students.viewlets import FileManager
    from waeup.kofa.browser import DEFAULT_IMAGE_PATH
    style = getSampleStyleSheet()
    data = []

    # Collect viewlets
    fm = FileManager(view.context, view.request, view)
    fm.update()
    if fm.viewlets:
        sc_translation = trans(_('Scanned Documents'), lang)
        data.append(Paragraph(sc_translation, HEADING_STYLE))
        # Insert list of scanned documents
        table_data = []
        for viewlet in fm.viewlets:
            f_label = Paragraph(trans(viewlet.label, lang), ENTRY1_STYLE)
            img_path = getattr(getUtility(IExtFileStore).getFileByContext(
                view.context, attr=viewlet.download_name), 'name', None)
            f_text = Paragraph(trans(_('(not provided)'),lang), ENTRY1_STYLE)
            if img_path is None:
                pass
            elif not img_path[-4:] in ('.jpg', '.JPG'):
                # reportlab requires jpg images, I think.
                f_text = Paragraph('%s (not displayable)' % (
                    viewlet.title,), ENTRY1_STYLE)
            else:
                f_text = Image(img_path, width=2*cm, height=1*cm, kind='bound')
            table_data.append([f_label, f_text])
        if table_data:
            # safety belt; empty tables lead to problems.
            data.append(Table(table_data, style=SLIP_STYLE))
    return data

class StudentsUtils(grok.GlobalUtility):
    """A collection of methods subject to customization.
    """
    grok.implements(IStudentsUtils)

    def getReturningData(self, student):
        """ Define what happens after school fee payment
        depending on the student's senate verdict.

        In the base configuration current level is always increased
        by 100 no matter which verdict has been assigned.
        """
        new_level = student['studycourse'].current_level + 100
        new_session = student['studycourse'].current_session + 1
        return new_session, new_level

    def setReturningData(self, student):
        """ Define what happens after school fee payment
        depending on the student's senate verdict.

        This method folllows the same algorithm as getReturningData but
        it also sets the new values.
        """
        new_session, new_level = self.getReturningData(student)
        try:
            student['studycourse'].current_level = new_level
        except ConstraintNotSatisfied:
            # Do not change level if level exceeds the
            # certificate's end_level.
            pass
        student['studycourse'].current_session = new_session
        verdict = student['studycourse'].current_verdict
        student['studycourse'].current_verdict = '0'
        student['studycourse'].previous_verdict = verdict
        return

    def _getSessionConfiguration(self, session):
        try:
            return grok.getSite()['configuration'][str(session)]
        except KeyError:
            return None

    def setPaymentDetails(self, category, student,
            previous_session, previous_level):
        """Create Payment object and set the payment data of a student for
        the payment category specified.

        """
        p_item = u''
        amount = 0.0
        if previous_session:
            if previous_session < student['studycourse'].entry_session:
                return _('The previous session must not fall below '
                         'your entry session.'), None
            if category == 'schoolfee':
                # School fee is always paid for the following session
                if previous_session > student['studycourse'].current_session:
                    return _('This is not a previous session.'), None
            else:
                if previous_session > student['studycourse'].current_session - 1:
                    return _('This is not a previous session.'), None
            p_session = previous_session
            p_level = previous_level
            p_current = False
        else:
            p_session = student['studycourse'].current_session
            p_level = student['studycourse'].current_level
            p_current = True
        academic_session = self._getSessionConfiguration(p_session)
        if academic_session == None:
            return _(u'Session configuration object is not available.'), None
        # Determine fee.
        if category == 'schoolfee':
            try:
                certificate = student['studycourse'].certificate
                p_item = certificate.code
            except (AttributeError, TypeError):
                return _('Study course data are incomplete.'), None
            if previous_session:
                # Students can pay for previous sessions in all
                # workflow states.  Fresh students are excluded by the
                # update method of the PreviousPaymentAddFormPage.
                if previous_level == 100:
                    amount = getattr(certificate, 'school_fee_1', 0.0)
                else:
                    amount = getattr(certificate, 'school_fee_2', 0.0)
            else:
                if student.state == CLEARED:
                    amount = getattr(certificate, 'school_fee_1', 0.0)
                elif student.state == RETURNING:
                    # In case of returning school fee payment the
                    # payment session and level contain the values of
                    # the session the student has paid for. Payment
                    # session is always next session.
                    p_session, p_level = self.getReturningData(student)
                    academic_session = self._getSessionConfiguration(p_session)
                    if academic_session == None:
                        return _(
                            u'Session configuration object is not available.'
                            ), None
                    amount = getattr(certificate, 'school_fee_2', 0.0)
                elif student.is_postgrad and student.state == PAID:
                    # Returning postgraduate students also pay for the
                    # next session but their level always remains the
                    # same.
                    p_session += 1
                    academic_session = self._getSessionConfiguration(p_session)
                    if academic_session == None:
                        return _(
                            u'Session configuration object is not available.'
                            ), None
                    amount = getattr(certificate, 'school_fee_2', 0.0)
        elif category == 'clearance':
            try:
                p_item = student['studycourse'].certificate.code
            except (AttributeError, TypeError):
                return _('Study course data are incomplete.'), None
            amount = academic_session.clearance_fee
        elif category == 'bed_allocation':
            p_item = self.getAccommodationDetails(student)['bt']
            amount = academic_session.booking_fee
        elif category == 'hostel_maintenance':
            amount = academic_session.maint_fee
            bedticket = student['accommodation'].get(
                str(student.current_session), None)
            if bedticket:
                p_item = bedticket.bed_coordinates
            else:
                # Should not happen because this is already checked
                # in the browser module, but anyway ...
                portal_language = getUtility(IKofaUtils).PORTAL_LANGUAGE
                p_item = trans(_('no bed allocated'), portal_language)
        if amount in (0.0, None):
            return _('Amount could not be determined.'), None
        for key in student['payments'].keys():
            ticket = student['payments'][key]
            if ticket.p_state == 'paid' and\
               ticket.p_category == category and \
               ticket.p_item == p_item and \
               ticket.p_session == p_session:
                  return _('This type of payment has already been made.'), None
        payment = createObject(u'waeup.StudentOnlinePayment')
        timestamp = ("%d" % int(time()*10000))[1:]
        payment.p_id = "p%s" % timestamp
        payment.p_category = category
        payment.p_item = p_item
        payment.p_session = p_session
        payment.p_level = p_level
        payment.p_current = p_current
        payment.amount_auth = amount
        return None, payment

    def setBalanceDetails(self, category, student,
            balance_session, balance_level, balance_amount):
        """Create Payment object and set the payment data of a student for.

        """
        p_item = u'Balance'
        p_session = balance_session
        p_level = balance_level
        p_current = False
        amount = balance_amount
        academic_session = self._getSessionConfiguration(p_session)
        if academic_session == None:
            return _(u'Session configuration object is not available.'), None
        if amount in (0.0, None) or amount < 0:
            return _('Amount must be greater than 0.'), None
        for key in student['payments'].keys():
            ticket = student['payments'][key]
            if ticket.p_state == 'paid' and\
               ticket.p_category == 'balance' and \
               ticket.p_item == p_item and \
               ticket.p_session == p_session:
                  return _('This type of payment has already been made.'), None
        payment = createObject(u'waeup.StudentOnlinePayment')
        timestamp = ("%d" % int(time()*10000))[1:]
        payment.p_id = "p%s" % timestamp
        payment.p_category = category
        payment.p_item = p_item
        payment.p_session = p_session
        payment.p_level = p_level
        payment.p_current = p_current
        payment.amount_auth = amount
        return None, payment

    def getAccommodationDetails(self, student):
        """Determine the accommodation data of a student.
        """
        d = {}
        d['error'] = u''
        hostels = grok.getSite()['hostels']
        d['booking_session'] = hostels.accommodation_session
        d['allowed_states'] = hostels.accommodation_states
        d['startdate'] = hostels.startdate
        d['enddate'] = hostels.enddate
        d['expired'] = hostels.expired
        # Determine bed type
        studycourse = student['studycourse']
        certificate = getattr(studycourse,'certificate',None)
        entry_session = studycourse.entry_session
        current_level = studycourse.current_level
        if None in (entry_session, current_level, certificate):
            return d
        end_level = certificate.end_level
        if current_level == 10:
            bt = 'pr'
        elif entry_session == grok.getSite()['hostels'].accommodation_session:
            bt = 'fr'
        elif current_level >= end_level:
            bt = 'fi'
        else:
            bt = 're'
        if student.sex == 'f':
            sex = 'female'
        else:
            sex = 'male'
        special_handling = 'regular'
        d['bt'] = u'%s_%s_%s' % (special_handling,sex,bt)
        return d

    def selectBed(self, available_beds):
        """Select a bed from a list of available beds.

        In the base configuration we select the first bed found,
        but can also randomize the selection if we like.
        """
        return available_beds[0]

    def renderPDFAdmissionLetter(self, view, student=None):
        """Render pdf admission letter.
        """
        if student is None:
            return
        style = getSampleStyleSheet()
        creator = self.getPDFCreator(student)
        data = []
        doc_title = view.label
        author = '%s (%s)' % (view.request.principal.title,
                              view.request.principal.id)
        footer_text = view.label.split('\n')
        if len(footer_text) > 1:
            # We can add a department in first line
            footer_text = footer_text[1]
        else:
            # Only the first line is used for the footer
            footer_text = footer_text[0]
        if getattr(student, 'student_id', None) is not None:
            footer_text = "%s - %s - " % (student.student_id, footer_text)

        # Admission text
        portal_language = getUtility(IKofaUtils).PORTAL_LANGUAGE
        inst_name = grok.getSite()['configuration'].name
        text = trans(_(
            'This is to inform you that you have been provisionally'
            ' admitted into ${a} as follows:', mapping = {'a': inst_name}),
            portal_language)
        html = format_html(text)
        data.append(Paragraph(html, NOTE_STYLE))
        data.append(Spacer(1, 20))

        # Student data
        data.append(render_student_data(view))

        # Insert history
        data.append(Spacer(1, 20))
        datelist = student.history.messages[0].split()[0].split('-')
        creation_date = u'%s/%s/%s' % (datelist[2], datelist[1], datelist[0])
        text = trans(_(
            'Your Kofa student record was created on ${a}.',
            mapping = {'a': creation_date}),
            portal_language)
        html = format_html(text)
        data.append(Paragraph(html, NOTE_STYLE))

        # Create pdf stream
        view.response.setHeader(
            'Content-Type', 'application/pdf')
        pdf_stream = creator.create_pdf(
            data, None, doc_title, author=author, footer=footer_text,
            note=None)
        return pdf_stream

    def getPDFCreator(self, context):
        """Get a pdf creator suitable for `context`.

        The default implementation always returns the default creator.
        """
        return getUtility(IPDFCreator)

    def renderPDF(self, view, filename='slip.pdf', student=None,
                  studentview=None,
                  tableheader_1=None, tabledata_1=None,
                  tableheader_2=None, tabledata_2=None,
                  tableheader_3=None, tabledata_3=None,
                  note=None, signatures=None, sigs_in_footer=(),
                  show_scans=True, topMargin=1.5):
        """Render pdf slips for various pages.
        """
        # XXX: tell what the different parameters mean
        style = getSampleStyleSheet()
        creator = self.getPDFCreator(student)
        data = []
        doc_title = view.label
        author = '%s (%s)' % (view.request.principal.title,
                              view.request.principal.id)
        footer_text = view.label.split('\n')
        if len(footer_text) > 2:
            # We can add a department in first line
            footer_text = footer_text[1]
        else:
            # Only the first line is used for the footer
            footer_text = footer_text[0]
        if getattr(student, 'student_id', None) is not None:
            footer_text = "%s - %s - " % (student.student_id, footer_text)

        # Insert student data table
        portal_language = getUtility(IKofaUtils).PORTAL_LANGUAGE
        if student is not None:
            bd_translation = trans(_('Base Data'), portal_language)
            data.append(Paragraph(bd_translation, HEADING_STYLE))
            data.append(render_student_data(studentview))

        # Insert widgets
        if view.form_fields:
            data.append(Paragraph(view.title, HEADING_STYLE))
            portal_language = getUtility(IKofaUtils).PORTAL_LANGUAGE
            separators = getattr(self, 'SEPARATORS_DICT', {})
            table = creator.getWidgetsTable(
                view.form_fields, view.context, None, lang=portal_language,
                separators=separators)
            data.append(table)

        # Insert scanned docs
        if show_scans:
            data.extend(docs_as_flowables(view, portal_language))

        # Insert history
        if filename.startswith('clearance'):
            hist_translation = trans(_('Workflow History'), portal_language)
            data.append(Paragraph(hist_translation, HEADING_STYLE))
            data.extend(creator.fromStringList(student.history.messages))

       # Insert 1st content table (optionally on second page)
        if tabledata_1 and tableheader_1:
            #data.append(PageBreak())
            #data.append(Spacer(1, 20))
            data.append(Paragraph(view.content_title_1, HEADING_STYLE))
            data.append(Spacer(1, 8))
            contenttable = render_table_data(tableheader_1,tabledata_1)
            data.append(contenttable)

       # Insert 2nd content table (optionally on second page)
        if tabledata_2 and tableheader_2:
            #data.append(PageBreak())
            #data.append(Spacer(1, 20))
            data.append(Paragraph(view.content_title_2, HEADING_STYLE))
            data.append(Spacer(1, 8))
            contenttable = render_table_data(tableheader_2,tabledata_2)
            data.append(contenttable)

       # Insert 3rd content table (optionally on second page)
        if tabledata_3 and tableheader_3:
            #data.append(PageBreak())
            #data.append(Spacer(1, 20))
            data.append(Paragraph(view.content_title_3, HEADING_STYLE))
            data.append(Spacer(1, 8))
            contenttable = render_table_data(tableheader_3,tabledata_3)
            data.append(contenttable)

        # Insert signatures
        if signatures and not sigs_in_footer:
            data.append(Spacer(1, 20))
            signaturetable = get_signature_table(signatures)
            data.append(signaturetable)

        view.response.setHeader(
            'Content-Type', 'application/pdf')
        try:
            pdf_stream = creator.create_pdf(
                data, None, doc_title, author=author, footer=footer_text,
                note=note, sigs_in_footer=sigs_in_footer, topMargin=topMargin)
        except IOError:
            view.flash('Error in image file.')
            return view.redirect(view.url(view.context))
        return pdf_stream

    def maxCredits(self, studylevel):
        """Return maximum credits.

        In some universities maximum credits is not constant, it
        depends on the student's study level.
        """
        return 50

    def maxCreditsExceeded(self, studylevel, course):
        max_credits = self.maxCredits(studylevel)
        if max_credits and \
            studylevel.total_credits + course.credits > max_credits:
            return max_credits
        return 0

    VERDICTS_DICT = {
        '0': _('(not yet)'),
        'A': 'Successful student',
        'B': 'Student with carryover courses',
        'C': 'Student on probation',
        }

    SEPARATORS_DICT = {
        }

    #: A prefix used when generating new student ids. Each student id will
    #: start with this string. The default is 'K' for ``Kofa``.
    STUDENT_ID_PREFIX = u'K'