"""WAeUP portal certificates
"""
import grok
from hurry.workflow.interfaces import IWorkflowInfo, IWorkflowState
from zope.app.catalog.interfaces import ICatalog
from zope.component import getUtility
from zope.component.interfaces import IFactory, ComponentLookupError
from zope.interface import implementedBy
from waeup.sirp.university.interfaces import (
    ICertificate, ICertificateCourse, ICourse)

class Certificate(grok.Container):
    """A certificate.
    """
    grok.implements(ICertificate)

    def __init__(self, code=u'NA', title=u'Unnamed Certificate',
                 study_mode=None, start_level=None,
                 end_level=None, application_category=None, max_pass = u''):
        super(Certificate, self).__init__()
        self.code = code
        self.title = title
        self.study_mode = study_mode
        self.start_level = start_level
        self.end_level = end_level
        self.application_category = application_category
        self.max_pass = max_pass
        # Initialize workflow state...
        self.setReviewState('unchecked')

    def check(self):
        """Set Review State to ``checked``.
        """
        self.setReviewState(state='checked')

    def getReviewState(self):
        return IWorkflowState(self).getState()

    def setReviewState(self, state=None):
        """Try to set new state.

        Instead of simply setting a value, we fire a transition of a
        workflow. This might fail if, for instance, the required state
        is not part of the workflow or unreachable from current state.
        """
        if state == self.getReviewState():
            # Accept staying in the same state, even if workflow does
            # not allow this.
            return
        info = IWorkflowInfo(self)
        info.fireTransitionToward(state)
        return

    review_state = property(getReviewState, setReviewState)
    
    def addCourseRef(self, course, level=100, core_or_elective=True):
        """Add a course reference.
        """
        code = "%s_%s" % (course.code, level)
        self[code] = CertificateCourse(course, level, core_or_elective)
        self[code].__parent__ = self
        self[code].__name__ = code
        self._p_changed = True

    def delCourseRef(self, code, level=None):
        """Delete a course denoted by its code.
        """
        for key in self.keys():
            if self[key].getCourseCode() != code:
                continue
            if level is not None and str(self[key].level) != str(level):
                # found a course with correct key but wrong level...
                continue
            del self[key]
            self._p_changed = True
        return




class CertificateFactory(grok.GlobalUtility):
    """A factory for certificates.
    """
    grok.implements(IFactory)
    grok.name(u'waeup.Certificate')
    title = u"Create a new certificate.",
    description = u"This factory instantiates new certificate instances."

    def __call__(self, *args, **kw):
        return Certificate(*args, **kw)

    def getInterfaces(self):
        return implementedBy(Certificate)

class CertificateCourse(grok.Model):
    grok.implements(ICertificateCourse)

    def __init__(self, course=None, level=100, core_or_elective=True):
        self.course = course
        self.level = level
        self.core_or_elective = core_or_elective

    def getCourseCode(self):
        """Get code of a course.
        """
        return self.course.code
    
class CertificateCourseFactory(grok.GlobalUtility):
    """A factory for certificate courses.
    """
    grok.implements(IFactory)
    grok.name(u'waeup.CertificateCourse')
    title = u"Create a new certificate course.",
    description = u"This factory instantiates new certificate courses."

    def __call__(self, *args, **kw):
        return CertificateCourse(*args, **kw)

    def getInterfaces(self):
        return implementedBy(CertificateCourse)

@grok.subscribe(ICourse, grok.IObjectRemovedEvent)
def removedCourseHandler(course, event):
    """If a course is deleted, we make sure that also references in a
       certificatecontainer are removed.
    """
    code = course.code

    # Find all certcourses that reference the given course...
    try:
        cat = getUtility(ICatalog, name='certcourses_catalog')
    except ComponentLookupError:
        # catalog not available. This might happen during tests.
        return
        
    results = cat.searchResults(course_code=(code, code))
    for certcourse in results:
        # Remove that reference...
        cert = certcourse.__parent__
        cert.delCourseRef(code)
        cert._p_changed = True
    return