from zope.component import queryUtility
from zope.deprecation import deprecated
from zope.interface import implements
from zope.interface.interface import InterfaceClass

from webob import Request as WebobRequest

from repoze.bfg.interfaces import IRequest
from repoze.bfg.interfaces import IRouteRequest

def make_request_ascii(event):
    """ An event handler that causes the request charset to be ASCII;
    used as an INewRequest subscriber so code written before 0.7.0 can
    continue to work without a change"""
    request = event.request
    request.charset = None

class Request(WebobRequest):
    implements(IRequest)
    charset = 'utf-8'

    # override default WebOb "environ['adhoc_attr']" mutation behavior
    __getattr__ = object.__getattribute__
    __setattr__ = object.__setattr__
    __delattr__ = object.__delattr__

    # b/c dict interface for "root factory" code that expects a bare
    # environ.  Explicitly omitted dict methods: clear (unnecessary),
    # copy (implemented by WebOb), fromkeys (unnecessary)
    
    def __contains__(self, k):
        return self.environ.__contains__(k)

    def __delitem__(self, k):
        return self.environ.__delitem__(k)

    def __getitem__(self, k):
        return self.environ.__getitem__(k)

    def __iter__(self):
        return iter(self.environ)

    def __setitem__(self, k, v):
        self.environ[k] = v

    def get(self, k, default=None):
        return self.environ.get(k, default)

    def has_key(self, k):
        return self.environ.has_key(k)

    def items(self):
        return self.environ.items()

    def iteritems(self):
        return self.environ.iteritems()

    def iterkeys(self):
        return self.environ.iterkeys()

    def itervalues(self):
        return self.environ.itervalues()

    def keys(self):
        return self.environ.keys()

    def pop(self, k):
        return self.environ.pop(k)

    def popitem(self):
        return self.environ.popitem()

    def setdefault(self, v, default):
        return self.environ.setdefault(v, default)

    def update(self, v, **kw):
        return self.environ.update(v, **kw)

    def values(self):
        return self.environ.values()

def route_request_iface(name):
    return InterfaceClass('%s_IRequest' % name, (IRouteRequest,))

def add_global_response_headers(request, headerlist):
    attrs = request.__dict__
    response_headers = attrs.setdefault('global_response_headers', [])
    response_headers.extend(headerlist)

from repoze.bfg.threadlocal import get_current_request as get_request # b/c

deprecated('get_request',
           'As of repoze.bfg 1.0, any import of get_request from'
           '``repoze.bfg.request`` is '
           'deprecated.  Use ``from repoze.bfg.threadlocal import '
           'get_current_request instead.')