##############################################################################
#
# Copyright (c) 2001 Zope Corporation and Contributors. All Rights
# Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL).  A copy of the ZPL should accompany this
# distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
""" Class: HTTPBasicAuthHelper

$Id: HTTPBasicAuthHelper.py 70851 2006-10-20 19:25:56Z jens $
"""

from zExceptions import Unauthorized

from AccessControl.SecurityInfo import ClassSecurityInfo
from App.class_init import default__class_init__ as InitializeClass

from zope.interface import Interface

from Products.PageTemplates.PageTemplateFile import PageTemplateFile
from Products.PluggableAuthService.interfaces.plugins import \
        ILoginPasswordHostExtractionPlugin
from Products.PluggableAuthService.interfaces.plugins import \
        IChallengePlugin
from Products.PluggableAuthService.interfaces.plugins import \
        ICredentialsResetPlugin
from Products.PluggableAuthService.plugins.BasePlugin import BasePlugin
from Products.PluggableAuthService.utils import classImplements


manage_addHTTPBasicAuthHelperForm = PageTemplateFile(
    'www/hbAdd', globals(), __name__='manage_addHTTPBasicAuthHelperForm' )

class IHTTPBasicAuthHelper(Interface):
    """ Marker interface.
    """

def addHTTPBasicAuthHelper( dispatcher, id, title=None, REQUEST=None ):

    """ Add a HTTP Basic Auth Helper to a Pluggable Auth Service.
    """
    sp = HTTPBasicAuthHelper( id, title )
    dispatcher._setObject( sp.getId(), sp )

    if REQUEST is not None:
        REQUEST['RESPONSE'].redirect( '%s/manage_workspace'
                                      '?manage_tabs_message='
                                      'HTTPBasicAuthHelper+added.'
                                    % dispatcher.absolute_url() )


class HTTPBasicAuthHelper( BasePlugin ):

    """ Multi-plugin for managing details of HTTP Basic Authentication.
    """
    meta_type = 'HTTP Basic Auth Helper'

    security = ClassSecurityInfo()

    protocol = "http" # The PAS challenge 'protocol' we use.

    def __init__( self, id, title=None ):
        self._setId( id )
        self.title = title

    security.declarePrivate( 'extractCredentials' )
    def extractCredentials( self, request ):

        """ Extract basic auth credentials from 'request'.
        """
        creds = {}
        login_pw = request._authUserPW()

        if login_pw is not None:
            name, password = login_pw

            creds[ 'login' ] = name
            creds[ 'password' ] = password
            creds[ 'remote_host' ] = request.get('REMOTE_HOST', '')

            try:
                creds[ 'remote_address' ] = request.getClientAddr()
            except AttributeError:
                creds[ 'remote_address' ] = ''

        return creds

    security.declarePrivate( 'challenge' )
    def challenge( self, request, response, **kw ):

        """ Challenge the user for credentials.
        """
        realm = response.realm
        if realm:
            response.addHeader('WWW-Authenticate',
                               'basic realm="%s"' % realm)
        m = "<strong>You are not authorized to access this resource.</strong>"
        if response.debug_mode:
            if response._auth:
                m = m + '<p>\nUsername and password are not correct.'
            else:
                m = m + '<p>\nNo Authorization header found.'

        response.setBody(m, is_error=1)
        response.setStatus(401)
        return 1

    security.declarePrivate( 'resetCredentials' )
    def resetCredentials( self, request, response ):

        """ Raise unauthorized to tell browser to clear credentials.
        """
        # XXX:  Does this need to check whether we have an HTTP response?
        response.unauthorized()

classImplements( HTTPBasicAuthHelper
               , IHTTPBasicAuthHelper
               , ILoginPasswordHostExtractionPlugin
               , IChallengePlugin
               , ICredentialsResetPlugin
               )

InitializeClass( HTTPBasicAuthHelper )
