## $Id: batching.py 8302 2012-04-28 07:58:39Z 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
##
"""Batch processing components for academics objects.

Batch processors eat CSV files to add, update or remove large numbers
of certain kinds of objects at once.

Here we define the processors for academics specific objects like
faculties, departments and the like.
"""
import grok
from zope.interface import Interface
from zope.component import queryUtility
from zope.schema import getFields
from zope.catalog.interfaces import ICatalog
from waeup.kofa.interfaces import IBatchProcessor, IGNORE_MARKER, FatalCSVError
from waeup.kofa.university.interfaces import (
    IFacultiesContainer, IFaculty, ICourse, IDepartment, ICertificate,
    ICertificateCourse)
from waeup.kofa.utils.batching import BatchProcessor

class FacultyProcessor(BatchProcessor):
    """A batch processor for IFaculty objects.
    """
    grok.implements(IBatchProcessor)
    grok.provides(IBatchProcessor)
    grok.context(Interface)
    util_name = 'facultyprocessor'
    grok.name(util_name)

    name = u'Faculty Processor'
    iface = IFaculty

    location_fields = ['code',]
    factory_name = 'waeup.Faculty'

    mode = None

    def parentsExist(self, row, site):
        return 'faculties' in site.keys()

    def entryExists(self, row, site):
        return row['code'] in site['faculties'].keys()

    def getParent(self, row, site):
        return site['faculties']

    def getEntry(self, row, site):
        if not self.entryExists(row, site):
            return None
        parent = self.getParent(row, site)
        return parent.get(row['code'])

    def addEntry(self, obj, row, site):
        parent = self.getParent(row, site)
        parent.addFaculty(obj)
        return

    def delEntry(self, row, site):
        parent = self.getParent(row, site)
        del parent[row['code']]
        pass

class DepartmentProcessor(BatchProcessor):
    """A batch processor for IDepartment objects.
    """
    grok.implements(IBatchProcessor)
    grok.provides(IBatchProcessor)
    grok.context(Interface)
    util_name = 'departmentprocessor'
    grok.name(util_name)

    name = u'Department Processor'
    iface = IDepartment

    location_fields = ['code', 'faculty_code']
    factory_name = 'waeup.Department'

    mode = None

    def parentsExist(self, row, site):
        if not 'faculties' in site.keys():
            return False
        return row['faculty_code'] in site['faculties']

    def entryExists(self, row, site):
        if not self.parentsExist(row, site):
            return False
        parent = self.getParent(row, site)
        return row['code'] in parent.keys()

    def getParent(self, row, site):
        return site['faculties'][row['faculty_code']]

    def getEntry(self, row, site):
        if not self.entryExists(row, site):
            return None
        parent = self.getParent(row, site)
        return parent.get(row['code'])

    def addEntry(self, obj, row, site):
        parent = self.getParent(row, site)
        parent.addDepartment(obj)
        return

    def delEntry(self, row, site):
        parent = self.getParent(row, site)
        del parent[row['code']]
        return

class CourseProcessor(BatchProcessor):
    """A batch processor for ICourse objects.
    """
    grok.implements(IBatchProcessor)
    grok.provides(IBatchProcessor)
    grok.context(Interface)
    util_name = 'courseprocessor'
    grok.name(util_name)

    name = u'Course Processor'
    iface = ICourse

    location_fields = ['code', 'faculty_code', 'department_code']
    factory_name = 'waeup.Course'

    mode = None

    def parentsExist(self, row, site):
        if not 'faculties' in site.keys():
            return False
        if not row['faculty_code'] in site['faculties'].keys():
            return False
        faculty = site['faculties'][row['faculty_code']]
        return row['department_code'] in faculty.keys()

    def entryExists(self, row, site):
        if not self.parentsExist(row, site):
            return False
        parent = self.getParent(row, site)
        return row['code'] in parent.keys()

    def getParent(self, row, site):
        dept = site['faculties'][row['faculty_code']][row['department_code']]
        return dept.courses

    def getEntry(self, row, site):
        if not self.entryExists(row, site):
            return None
        parent = self.getParent(row, site)
        return parent.get(row['code'])

    def addEntry(self, obj, row, site):
        parent = self.getParent(row, site)
        parent.addCourse(obj)
        return

    def delEntry(self, row, site):
        parent = self.getParent(row, site)
        del parent[row['code']]
        return

class CertificateProcessor(BatchProcessor):
    """A batch processor for ICertificate objects.
    """
    grok.implements(IBatchProcessor)
    grok.provides(IBatchProcessor)
    grok.context(Interface)
    util_name = 'certificateprocessor'
    grok.name(util_name)

    name = u'Certificate Processor'
    iface = ICertificate

    location_fields = ['code']
    factory_name = 'waeup.Certificate'

    mode = None

    @property
    def available_fields(self):
        fields = getFields(self.iface)
        return sorted(list(set(
            ['faculty_code','department_code'] + fields.keys())))

    def checkHeaders(self, headerfields, mode='create'):
        req = self.req[mode]
        # Check for required fields...
        for field in req:
            if not field in headerfields:
                raise FatalCSVError(
                    "Need at least columns %s for import!" %
                    ', '.join(["'%s'" % x for x in req]))
        # Check for double fields. Cannot happen because this error is
        # already catched in views
        not_ignored_fields = [x for x in headerfields
                              if not x.startswith('--')]
        if len(set(not_ignored_fields)) < len(not_ignored_fields):
            raise FatalCSVError(
                "Double headers: each column name may only appear once.")
        if mode == 'create':
            if not 'faculty_code' in headerfields \
                and not 'department_code' in headerfields :
                raise FatalCSVError(
                    "Need at least columns faculty_code and department_code")
        return True

    def parentsExist(self, row, site):
        return self.getParent(row,site) is not None

    def entryExists(self, row, site):
        parent = self.getParent(row, site)
        if parent is not None:
            return row['code'] in parent.keys()
        return False

    def getParent(self, row, site):
        if not 'faculties' in site.keys():
            return None
        # If both faculty and department codes are provided, use
        # these to get parent.
        if row.get('faculty_code',None) not in (None, IGNORE_MARKER) and \
            row.get('department_code',None) not in (None, IGNORE_MARKER):
            if not row['faculty_code'] in site['faculties'].keys():
                return None
            faculty = site['faculties'][row['faculty_code']]
            if not row['department_code'] in faculty.keys():
                return None
            dept = faculty[row['department_code']]
            return dept.certificates
        # If department code or faculty code is missing,
        # use catalog to get parent. Makes only sense in update mode but
        # does also work in create mode.
        cat = queryUtility(ICatalog, name='certificates_catalog')
        results = list(
            cat.searchResults(code=(row['code'], row['code'])))
        if results:
            return results[0].__parent__
        return None

    def getEntry(self, row, site):
        parent = self.getParent(row, site)
        if parent is not None:
            return parent.get(row['code'])
        return None

    def addEntry(self, obj, row, site):
        parent = self.getParent(row, site)
        parent.addCertificate(obj)
        return

    def delEntry(self, row, site):
        parent = self.getParent(row, site)
        del parent[row['code']]
        return

class CertificateCourseProcessor(BatchProcessor):
    """A batch processor for ICertificateCourse objects.
    """
    grok.implements(IBatchProcessor)
    grok.provides(IBatchProcessor)
    grok.context(Interface)
    util_name = 'certificatecourseprocessor'
    grok.name(util_name)

    name = u'CertificateCourse Processor'
    iface = ICertificateCourse

    location_fields = ['course', 'level', 'faculty_code', 'department_code',
                       'certificate_code',]
    factory_name = 'waeup.CertificateCourse'

    mode = None

    def parentsExist(self, row, site):
        if not 'faculties' in site.keys():
            return False
        if not row['faculty_code'] in site['faculties'].keys():
            return False
        faculty = site['faculties'][row['faculty_code']]
        if not row['department_code'] in faculty.keys():
            return False
        dept = faculty[row['department_code']]
        return row['certificate_code'] in dept.certificates.keys()

    def entryExists(self, row, site):
        if not self.parentsExist(row, site):
            return False
        parent = self.getParent(row, site)
        code = "%s_%s" % (row['course'].code, row['level'])
        return code in parent.keys()

    def getParent(self, row, site):
        dept = site['faculties'][row['faculty_code']][row['department_code']]
        return dept.certificates[row['certificate_code']]

    def getEntry(self, row, site):
        if not self.entryExists(row, site):
            return None
        parent = self.getParent(row, site)
        return parent.get("%s_%s" % (row['course'].code, row['level']))

    def addEntry(self, obj, row, site):
        parent = self.getParent(row, site)
        parent.addCourseRef(row['course'],
                            row['level'], row['mandatory'])
        return

    def delEntry(self, row, site):
        parent = self.getParent(row, site)
        parent.delCourseRef(row['course'].code, row['level'])
        return