from contextlib import contextmanager

from warnings import warn

import rql

from cubicweb.web.request import CubicWebRequestBase

from cubicweb import repoapi

import cubicweb

import cubicweb.web

from pyramid import httpexceptions

from pyramid_cubicweb import authplugin

import logging

log = logging.getLogger(__name__)

@contextmanager

def cw_to_pyramid(request):

    """Wrap a call to the cubicweb API.

    All CW exceptions will be transformed into their pyramid equivalent.

    When needed, some CW reponse bits may be converted too (mainly headers)"""

    try:

        yield

    except cubicweb.web.Redirect as ex:

        assert 300 <= ex.status < 400

        raise httpexceptions.status_map[ex.status](ex.location)

    except cubicweb.web.StatusResponse as ex:

        warn('[3.16] StatusResponse is deprecated use req.status_out',

             DeprecationWarning, stacklevel=2)

        request.body = ex.content

        request.status_int = ex.status

    except cubicweb.web.Unauthorized as ex:

        raise httpexceptions.HTTPForbidden(

            request.cw_request._(

                'You\'re not authorized to access this page. '

                'If you think you should, please contact the site '

                'administrator.'))

    except cubicweb.web.Forbidden:

        raise httpexceptions.HTTPForbidden(

            request.cw_request._(

                'This action is forbidden. '

                'If you think it should be allowed, please contact the site '

                'administrator.'))

    except (rql.BadRQLQuery, cubicweb.web.RequestError) as ex:

        raise

class CubicWebPyramidRequest(CubicWebRequestBase):

    def __init__(self, request):

        self._request = request

        self.path = request.upath_info

        vreg = request.registry['cubicweb.registry']

        https = request.scheme == 'https'

        post = request.params

        headers_in = request.headers

        super(CubicWebPyramidRequest, self).__init__(vreg, https, post,

                                                     headers=headers_in)

    def is_secure(self):

        return self._request.scheme == 'https'

    def relative_path(self, includeparams=True):

        path = self._request.path[1:]

        if includeparams and self._request.query_string:

            return '%s?%s' % (path, self._request.query_string)

        return path

    def instance_uri(self):

        return self._request.application_url

    def get_full_path(self):

        path = self._request.path

        if self._request.query_string:

            return '%s?%s' % (path, self._request.query_string)

        return path

    def http_method(self):

        return self._request.method

    def _set_status_out(self, value):

        self._request.response.status_int = value

    def _get_status_out(self):

        return self._request.response.status_int

    status_out = property(_get_status_out, _set_status_out)

def render_view(request, vid, **kwargs):

    vreg = request.registry['cubicweb.registry']

    # XXX The select() function could, know how to handle a pyramid

    # request, and feed it directly to the views that supports it.

    # On the other hand, we could refine the View concept and decide it works

    # with a cnx, and never with a WebRequest

    with cw_to_pyramid(request):

        view = vreg['views'].select(vid, request.cw_request, **kwargs)

        view.set_stream()

        view.render()

        return view._stream.getvalue()

def _cw_cnx(request):

    cnx = repoapi.ClientConnection(request.cw_session)

    def cleanup(request):

        if request.exception is not None:

            cnx.rollback()

        else:

            cnx.commit()

        cnx.__exit__(None, None, None)

    request.add_finished_callback(cleanup)

    cnx.__enter__()

    return cnx

def _cw_close_session(request):

    request.cw_session.close()

def _cw_session(request):

    """Obtains a cw session from a pyramid request"""

    repo = request.registry['cubicweb.repository']

    config = request.registry['cubicweb.config']

    if not request.authenticated_userid:

        login, password = config.anonymous_user()

        sessionid = repo.connect(login, password=password)

        session = repo._sessions[sessionid]

        request.add_finished_callback(_cw_close_session)

    else:

        session = request._cw_cached_session

    # XXX Ideally we store the cw session data in the pyramid session.

    # BUT some data in the cw session data dictionnary makes pyramid fail.

    session.data = request.session

    return session

def _cw_request(request):

    req = CubicWebPyramidRequest(request)

    req.set_cnx(request.cw_cnx)

    return req

def get_principals(login, request):

    repo = request.registry['cubicweb.repository']

    try:

        sessionid = repo.connect(

            str(login), __pyramid_directauth=authplugin.EXT_TOKEN)

        session = repo._sessions[sessionid]

        request._cw_cached_session = session

        request.add_finished_callback(_cw_close_session)

    except:

        log.exception("Failed")

        raise

    return session.user.groups

def hello_world(request):

    request.response.text = \

        u"<html><body>Hello %s</body></html>" % request.cw_cnx.user.login

    return request.response

def includeme(config):

    repo = config.registry['cubicweb.repository']

    repo.system_source.add_authentifier(authplugin.DirectAuthentifier())

    config.add_request_method(

        _cw_session, name='cw_session', property=True, reify=True)

    config.add_request_method(

        _cw_cnx, name='cw_cnx', property=True, reify=True)

    config.add_request_method(

        _cw_request, name='cw_request', property=True, reify=True)