import grok
from zope.component import getUtility, getMultiAdapter
from zope.component.interfaces import Invalid
from zope.exceptions import DuplicationError
from waeup.basecontainer import BaseContainer
from waeup.interfaces import IFacultyContainer
from waeup.viewlets import MainArea, LeftSidebar, Index, Add, FormWrapMixin
from interfaces import IFaculty
from faculty import Faculty

from zope.schema import ValidationError

class FacultyContainer(grok.Container):

    grok.implements(IFacultyContainer)
    grok.require('waeup.manageUniversity')
    
    name = u'Faculties'
   
    def getId(self, faculty):
        """We need a unified id for each faculty, which acts as key.
        """
        id = faculty.name
        id = id.replace(' ', '')
        return id.lower()
    
    def addFaculty(self, faculty):
        if not IFaculty.providedBy(faculty):
            raise TypeError('FacultyContainers contain only IFaculty instances')
        id = self.getId(faculty)
        self[id] = faculty

# We register FacultyContainer as a utility. This way we can
# call getUtility(IFacultyContainer) from anywhere in the code and
# get an instance of FacultyContainer.
grok.global_utility(FacultyContainer, provides=IFacultyContainer)

class Content(grok.Viewlet):
    grok.viewletmanager(MainArea)
    grok.context(IFacultyContainer)
    grok.view(Index)

    def getFaculties(self):
        """Convinience method to create a sorted list of faculties.

        It provides a list of dicts with entries for all data needed by
        usual list templates.
        """
        result = []
        for key, val in self.context.items():
            result.append(dict(id=key, name=val.name))
        return result

class AddFacultyForm(grok.AddForm):
    grok.context(IFacultyContainer)
    form_fields = grok.AutoFields(IFaculty)
    label = 'Add a faculty'

    @grok.action('Add faculty')
    def addFaculty(self, **data):
        faculty = getUtility(IFaculty)
        self.applyData(faculty, **data)
        try:
            self.context.addFaculty(faculty)
        except DuplicationError:
            self.status = Invalid('The name chosen already exists '
                                  'in the database')
            return
        self.redirect(self.url(self.context))

        
class AddFaculty(FormWrapMixin, grok.Viewlet):
    """A viewlet that wraps the `AddFacultyForm`.
    """
    grok.viewletmanager(MainArea)
    grok.context(IFacultyContainer)
    grok.view(Add)
    grok.require('waeup.manageUniversity')

    formview_name = 'addfacultyform' # The name of the formview we
                                     # want to be rendered in this
                                     # viewlet.


class AddFacultyLink(grok.Viewlet):
    """A link in the left sidebar displaying 'Add faculty'
    """
    grok.viewletmanager(LeftSidebar)
    grok.context(IFacultyContainer)
    grok.view(Index)
    grok.order(5)
    # This is so cool! This link is only displayed, when the user is
    # allowed to use it!
    grok.require('waeup.manageUniversity')
    
    def render(self):
        return u'<div class="portlet"><a href="add">Add faculty</a></div>'