"""WSGI request handler for cubicweb

:organization: Logilab

:copyright: 2008-2009 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.

:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr

:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses

"""

__docformat__ = "restructuredtext en"

from cubicweb import ObjectNotFound, AuthenticationError

from cubicweb.web import (NotFound, Redirect, DirectResponse, StatusResponse,

                       ExplicitLogin)

from cubicweb.web.application import CubicWebPublisher

from cubicweb.wsgi.request import CubicWebWsgiRequest

# See http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html

STATUS_CODE_TEXT = {

    100: 'CONTINUE',

    101: 'SWITCHING PROTOCOLS',

    200: 'OK',

    201: 'CREATED',

    202: 'ACCEPTED',

    203: 'NON-AUTHORITATIVE INFORMATION',

    204: 'NO CONTENT',

    205: 'RESET CONTENT',

    206: 'PARTIAL CONTENT',

    300: 'MULTIPLE CHOICES',

    301: 'MOVED PERMANENTLY',

    302: 'FOUND',

    303: 'SEE OTHER',

    304: 'NOT MODIFIED',

    305: 'USE PROXY',

    306: 'RESERVED',

    307: 'TEMPORARY REDIRECT',

    400: 'BAD REQUEST',

    401: 'UNAUTHORIZED',

    402: 'PAYMENT REQUIRED',

    403: 'FORBIDDEN',

    404: 'NOT FOUND',

    405: 'METHOD NOT ALLOWED',

    406: 'NOT ACCEPTABLE',

    407: 'PROXY AUTHENTICATION REQUIRED',

    408: 'REQUEST TIMEOUT',

    409: 'CONFLICT',

    410: 'GONE',

    411: 'LENGTH REQUIRED',

    412: 'PRECONDITION FAILED',

    413: 'REQUEST ENTITY TOO LARGE',

    414: 'REQUEST-URI TOO LONG',

    415: 'UNSUPPORTED MEDIA TYPE',

    416: 'REQUESTED RANGE NOT SATISFIABLE',

    417: 'EXPECTATION FAILED',

    500: 'INTERNAL SERVER ERROR',

    501: 'NOT IMPLEMENTED',

    502: 'BAD GATEWAY',

    503: 'SERVICE UNAVAILABLE',

    504: 'GATEWAY TIMEOUT',

    505: 'HTTP VERSION NOT SUPPORTED',

}

class WSGIResponse(object):

    """encapsulates the wsgi response parameters

    (code, headers and body if there is one)

    """

    def __init__(self, code, req, body=None):

        text = STATUS_CODE_TEXT.get(code, 'UNKNOWN STATUS CODE')

        self.status =  '%s %s' % (code, text)

        self.headers = [(str(k), str(v)) for k, v in req.headers_out.items()]

        if body:

            self.body = [body]

        else:

            self.body = []

    def __iter__(self):

        return iter(self.body)

class CubicWebWSGIApplication(object):

    """This is the wsgi application which will be called by the

    wsgi server with the WSGI ``environ`` and ``start_response``

    parameters.

    XXX: missing looping tasks and proper repository shutdown when

    the application is stopped.

    NOTE: no pyro

    """

    def __init__(self, config, debug=None, vreg=None):

        self.appli = CubicWebPublisher(config, debug=debug, vreg=vreg)

        self.debugmode = debug

        self.config = config

        self.base_url = None

#         self.base_url = config['base-url'] or config.default_base_url()

#         assert self.base_url[-1] == '/'

#         self.https_url = config['https-url']

#         assert not self.https_url or self.https_url[-1] == '/'

        try:

            self.url_rewriter = self.appli.vreg.select_component('urlrewriter')

        except ObjectNotFound:

            self.url_rewriter = None

    def _render(self, req):

        """this function performs the actual rendering

        XXX missing: https handling, url rewriting, cache management,

                     authentication

        """

        if self.base_url is None:

            self.base_url = self.config._base_url = req.base_url()

        # XXX https handling needs to be implemented

        if req.authmode == 'http':

            # activate realm-based auth

            realm = self.config['realm']

            req.set_header('WWW-Authenticate', [('Basic', {'realm' : realm })], raw=False)

        try:

            self.appli.connect(req)

        except AuthenticationError:

            return self.request_auth(req)

        except Redirect, ex:

            return self.redirect(req, ex.location)

        path = req.path

        if not path or path == "/":

            path = 'view'

        try:

            result = self.appli.publish(path, req)

        except DirectResponse, ex:

            return WSGIResponse(200, req, ex.response)

        except StatusResponse, ex:

            return WSGIResponse(ex.status, req, ex.content)

        except NotFound:

            result = self.appli.notfound_content(req)

            return WSGIResponse(404, req, result)

        except ExplicitLogin:  # must be before AuthenticationError

            return self.request_auth(req)

        except AuthenticationError:

            if self.config['auth-mode'] == 'cookie':

                # in cookie mode redirecting to the index view is enough :

                # either anonymous connection is allowed and the page will

                # be displayed or we'll be redirected to the login form

                msg = req._('you have been logged out')

#                 if req.https:

#                     req._base_url =  self.base_url

#                     req.https = False

                url = req.build_url('view', vid='index', __message=msg)

                return self.redirect(req, url)

            else:

                # in http we have to request auth to flush current http auth

                # information

                return self.request_auth(req, loggedout=True)

        except Redirect, ex:

            return self.redirect(req, ex.location)

        if not result:

            # no result, something went wrong...

            self.error('no data (%s)', req)

            # 500 Internal server error

            return self.redirect(req, req.build_url('error'))

        return WSGIResponse(200, req, result)

    def __call__(self, environ, start_response):

        """WSGI protocol entry point"""

        req = CubicWebWsgiRequest(environ, self.appli.vreg, self.base_url)

        response = self._render(req)

        start_response(response.status, response.headers)

        return response.body

    def redirect(self, req, location):

        """convenience function which builds a redirect WSGIResponse"""

        self.debug('redirecting to %s', location)

        req.set_header('location', str(location))

        return WSGIResponse(303, req)

    def request_auth(self, req, loggedout=False):

        """returns the appropriate WSGIResponse to require the user to log in

        """

#         if self.https_url and req.base_url() != self.https_url:

#             return self.redirect(self.https_url + 'login')

        if self.config['auth-mode'] == 'http':

            code = 401 # UNAUTHORIZED

        else:

            code = 403 # FORBIDDEN

        if loggedout:

#             if req.https:

#                 req._base_url =  self.base_url

#                 req.https = False

            content = self.appli.loggedout_content(req)

        else:

            content = self.appli.need_login_content(req)

        return WSGIResponse(code, req, content)

from logging import getLogger

from cubicweb import set_log_methods

set_log_methods(CubicWebWSGIApplication, getLogger('cubicweb.wsgi'))