## $Id: applicant.py 7240 2011-11-30 23:13:26Z 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
##
import os
from random import SystemRandom as r
import grok
from grok import index
from zope.component.interfaces import IFactory
from zope.securitypolicy.interfaces import IPrincipalRoleManager
from zope.interface import implementedBy
from hurry.workflow.interfaces import IWorkflowInfo, IWorkflowState
from waeup.sirp.app import University
from waeup.sirp.image import WAeUPImageFile
from waeup.sirp.imagestorage import DefaultFileStoreHandler
from waeup.sirp.interfaces import (
    IObjectHistory, IFileStoreHandler, IFileStoreNameChooser)
from waeup.sirp.utils.helpers import attrs_to_fields, get_current_principal
from waeup.sirp.applicants.interfaces import (
    IApplicant, IApplicantEdit,
    )
from waeup.sirp.applicants.workflow import INITIALIZED

def generate_applicant_id(container=None):
    if container is not None:
        aid = u"%s_%d" % (container.code, r().randint(99999,1000000))
        while aid in container.keys():
            aid = u"%s_%d" % (container.code, r().randint(99999,1000000))
        return aid
    else:
        # In some tests we don't use containers
        return u"xxx_1234"

class Applicant(grok.Model):
    grok.implements(IApplicant,IApplicantEdit)
    grok.provides(IApplicant)

    def __init__(self, container=None):
        super(Applicant, self).__init__()
        self.applicant_id = generate_applicant_id(container)
        self.password = None
        IWorkflowInfo(self).fireTransition('init')
        self.application_date = None
        return

    def loggerInfo(self, ob_class, comment=None):
        target = self.__name__
        return grok.getSite()['applicants'].logger_info(ob_class,target,comment)

    @property
    def state(self):
        state = IWorkflowState(self).getState()
        return state

    @property
    def history(self):
        history = IObjectHistory(self)
        return history

    @property
    def application_number(self):
        return self.applicant_id.split('_')[1]

    @property
    def fullname(self):
        # We do not necessarily have the middlenames attribute
        middlenames = getattr(self, 'middlenames', None)
        if middlenames:
            return '%s %s %s' % (self.firstname,
                middlenames, self.lastname)
        else:
            return '%s %s' % (self.firstname, self.lastname)

# Set all attributes of Applicant required in IApplicant as field
# properties. Doing this, we do not have to set initial attributes
# ourselves and as a bonus we get free validation when an attribute is
# set.
Applicant = attrs_to_fields(Applicant)

class ApplicantCatalog(grok.Indexes):
    """A catalog indexing :class:`Applicant` instances in the ZODB.
    """
    grok.site(University)
    grok.name('applicants_catalog')
    grok.context(IApplicant)

    access_code = index.Field(attribute='access_code')
    applicant_id = index.Field(attribute='applicant_id')
    reg_no = index.Field(attribute='reg_no')

class ApplicantFactory(grok.GlobalUtility):
    """A factory for applicants.
    """
    grok.implements(IFactory)
    grok.name(u'waeup.Applicant')
    title = u"Create a new applicant.",
    description = u"This factory instantiates new applicant instances."

    def __call__(self, *args, **kw):
        return Applicant(kw['container'])

    def getInterfaces(self):
        return implementedBy(Applicant)


#: The file id marker for applicant passport images
APPLICANT_IMAGE_STORE_NAME = 'img-applicant'

class ApplicantImageNameChooser(grok.Adapter):
    """A file id chooser for :class:`Applicant` objects.

    `context` is an :class:`Applicant` instance.

    The :class:`ApplicantImageNameChooser` can build/check file ids
    for :class:`Applicant` objects suitable for use with
    :class:`ExtFileStore` instances. The delivered file_id contains
    the file id marker for :class:`Applicant` object and the
    registration number or access code of the context applicant. Also
    the name of the connected applicant container will be part of the
    generated file id.

    This chooser is registered as an adapter providing
    :class:`waeup.sirp.interfaces.IFileStoreNameChooser`.

    File store name choosers like this one are only convenience
    components to ease the task of creating file ids for applicant
    objects. You are nevertheless encouraged to use them instead of
    manually setting up filenames for applicants.

    .. seealso:: :mod:`waeup.sirp.imagestorage`

    """
    grok.context(IApplicant)
    grok.implements(IFileStoreNameChooser)

    def checkName(self, name=None, attr=None):
        """Check whether the given name is a valid file id for the context.

        Returns ``True`` only if `name` equals the result of
        :meth:`chooseName`.

        The `attr` parameter is not taken into account for
        :class:`Applicant` context as the single passport image is the
        only file we store for applicants.
        """
        return name == self.chooseName()

    def chooseName(self, name=None, attr=None):
        """Get a valid file id for applicant context.

        *Example:*

        For an applicant with applicant_id. ``'app2001_1234'``
        and stored in an applicants container called
        ``'mycontainer'``, this chooser would create:

          ``'__img-applicant__mycontainer/app2001_1234.jpg'``

        meaning that the passport image of this applicant would be
        stored in the site-wide file storage in path:

          ``mycontainer/app2001_1234.jpg``

        If the context applicant has no parent, ``'_default'`` is used
        as parent name.

        The `attr` parameter is not taken into account for
        :class:`Applicant` context as the single passport image is the
        only file we store for applicants.

        """
        parent_name = getattr(
            getattr(self.context, '__parent__', None),
            '__name__', '_default')
        marked_filename = '__%s__%s/%s.jpg' % (
            APPLICANT_IMAGE_STORE_NAME,
            parent_name, self.context.applicant_id)
        return marked_filename


class ApplicantImageStoreHandler(DefaultFileStoreHandler, grok.GlobalUtility):
    """Applicant specific image handling.

    This handler knows in which path in a filestore to store applicant
    images and how to turn this kind of data into some (browsable)
    file object.

    It is called from the global file storage, when it wants to
    get/store a file with a file id starting with
    ``__img-applicant__`` (the marker string for applicant images).

    Like each other file store handler it does not handle the files
    really (this is done by the global file store) but only computes
    paths and things like this.
    """
    grok.implements(IFileStoreHandler)
    grok.name(APPLICANT_IMAGE_STORE_NAME)

    def pathFromFileID(self, store, root, file_id):
        """All applicants images are filed in directory ``applicants``.
        """
        marker, filename, basename, ext = store.extractMarker(file_id)
        sub_root = os.path.join(root, 'applicants')
        return super(ApplicantImageStoreHandler, self).pathFromFileID(
            store, sub_root, basename)

    def createFile(self, store, root, filename, file_id, file):
        """Create a browsable file-like object.
        """
        ext = os.path.splitext(filename)[1].lower()
        if ext not in ['.jpg', '.png']:
            raise ValueError('Only .jpg and .png allowed')
        # call super method to ensure that any old files with
        # different filename extension are deleted.
        file, path, file_obj =  super(
            ApplicantImageStoreHandler, self).createFile(
            store, root,  filename, file_id, file)
        return file, path, WAeUPImageFile(
            file_obj.filename, file_obj.data)

@grok.subscribe(IApplicant, grok.IObjectAddedEvent)
def handle_applicant_added(applicant, event):
    """If an applicant is added local and site roles are assigned.
    """
    role_manager = IPrincipalRoleManager(applicant)
    role_manager.assignRoleToPrincipal(
        'waeup.local.ApplicationOwner', applicant.applicant_id)
    # Assign current principal the global Applicant role
    role_manager = IPrincipalRoleManager(grok.getSite())
    role_manager.assignRoleToPrincipal(
        'waeup.Applicant', applicant.applicant_id)

    # Assign global applicant role for new applicant (alternative way)
    #account = IUserAccount(applicant)
    #account.roles = ['waeup.Applicant']

    return

@grok.subscribe(IApplicant, grok.IObjectRemovedEvent)
def handle_applicant_removed(applicant, event):
    """If an applicant is removed a message is logged.
    """
    comment = 'Applicant record removed'
    target = applicant.applicant_id
    # In some tests we don't have a principal
    try:
        user = get_current_principal().id
    except (TypeError, AttributeError):
        return
    try:
        grok.getSite()['applicants'].logger.info('%s - %s - %s' % (
            user, target, comment))
    except KeyError:
        # If we delete an entire university instance there won't be
        # an applicants subcontainer
        return
    return