from zope.component.zcml import handler
from zope.component.interface import provideInterface
from zope.configuration.exceptions import ConfigurationError
from zope.configuration.fields import GlobalObject

from zope.interface import Interface

from zope.schema import TextLine

from repoze.bfg.interfaces import IRequest
from repoze.bfg.interfaces import IViewPermission
from repoze.bfg.interfaces import IView

from repoze.bfg.security import ViewPermissionFactory

def view(_context,
         permission=None,
         for_=None,
         view=None,
         name="",
         request_type=IRequest,
         ):

    if not view:
        raise ConfigurationError('"view" attribute was not specified')

    if for_ is not None:
        _context.action(
            discriminator = None,
            callable = provideInterface,
            args = ('', for_)
            )

    if permission:
        pfactory = ViewPermissionFactory(permission)
        _context.action(
            discriminator = ('permission', for_,name, request_type,
                             IViewPermission),
            callable = handler,
            args = ('registerAdapter',
                    pfactory, (for_, request_type), IViewPermission, name,
                    _context.info),
            )

    _context.action(
        discriminator = ('view', for_, name, request_type, IView),
        callable = handler,
        args = ('registerAdapter',
                view, (for_, request_type), IView, name,
                _context.info),
        )

class IViewDirective(Interface):
    for_ = GlobalObject(
        title=u"The interface or class this view is for.",
        required=False
        )

    permission = TextLine(
        title=u"Permission",
        description=u"The permission needed to use the view.",
        required=False
        )

    view = GlobalObject(
        title=u"",
        description=u"The view function",
        required=False,
        )

    name = TextLine(
        title=u"The name of the view",
        description=u"""
        The name shows up in URLs/paths. For example 'foo' or
        'foo.html'.""",
        required=False,
        )

    request_type = GlobalObject(
        title=u"""The request type interface for the view""",
        description=(u"The view will be called if the interface represented by "
                     u"'request_type' is implemented by the request.  The "
                     u"default request type is repoze.bfg.interfaces.IRequest"),
        required=False
        )