"""Testing support for :mod:`waeup.sirp`.
"""
import os.path
import grok
import zope.component
import waeup.sirp
from zope.app.testing.functional import ZCMLLayer
from zope.component import getGlobalSiteManager

ftesting_zcml = os.path.join(
    os.path.dirname(waeup.sirp.__file__), 'ftesting.zcml')
FunctionalLayer = ZCMLLayer(ftesting_zcml, __name__, 'FunctionalLayer',
                            allow_teardown=True)

class WAeUPSIRPUnitTestLayer(object):
    """A layer for doctests that groks `waeup.sirp`.
    """
    @classmethod
    def setUp(self):
        import grok
        grok.testing.grok('waeup.sirp')

    @classmethod
    def tearDown(self):
        pass


def setUpZope(test=None):
    """Initialize a Zope-compatible environment.

    Currently, we only initialize the event machinery.
    """
    zope.component.eventtesting.setUp(test)

def cleanUpZope(test=None):
    """Clean up Zope-related registrations.

    Cleans up all registrations and the like.
    """
    cleanUp()

def maybe_grok():
    """Try to grok the :mod:`waeup.sirp` package.

    For many tests, even simple ones, we want the components defined
    somewhere in the :mod:`waeup.sirp` package being registered. While
    grokking the complete package can become expensive when done many
    times, we only want to grok if it did not happen
    before. Furthermore regrokking the whole package makes no sense if
    done already.

    :func:`maybe_grok` checks whether any eventhandlers are already
    registered and does nothing in that case.

    The grokking of :mod:`waeup.sirp` is done with warnings disabled.

    Returns ``True`` if grokking was done, ``False`` else.

    Sample
    ******
    
    Together with the :func:`setUpZope` and :func:`cleanUpZope`
    functions we then can do unittests with all components registered
    like this::

      import unittest2 as unittest # Want Python 2.7 features
      from waeup.sirp.testing import (
        maybe_grok, setUpZope, cleanUpZope,
        )
      from waeup.sirp.app import University

      class MyTestCase(unittest.TestCase):

          @classmethod
          def setUpClass(cls):
              grokked = maybe_grok()
              if grokked:
                  setUpZope(None)
              return

          @classmethod
          def tearDownClass(cls):
              cleanUpZope(None)

          def setUp(self):
              pass
        
          def tearDown(self):
              pass

          def test_jambdata_in_site(self):
              u = University()
              self.assertTrue('jambdata' in u.keys())
              return

    Here the component registration is done only once for the whole
    :class:`unittest.TestCase` and no ZODB is needed. That means
    inside the tests you can expect to have all :mod:`waeup.sirp`
    components (utilities, adapter, events) registered but as objects
    have here still have no place inside a ZODB things like 'browsing'
    won't work out of the box. The benefit is the faster test
    setup/teardown.
    """
    gsm =  getGlobalSiteManager()
    # If there are any event handlers registered already, we assume
    # that waeup.sirp was grokked already. There might be a batter
    # check, though.
    if len(list(gsm.registeredHandlers())) > 0:
        return False
    warnings.simplefilter('ignore') # disable (erraneous) warnings
    grok.testing.grok('waeup.sirp')
    warnings.simplefilter('default') # reenable warnings
    return True