# -*- encoding: utf-8 -*-
############################################################################9
#
# Copyright P. Christeas <p_christ@hol.gr> 2008-2010
# Copyright OpenERP SA, 2010 (http://www.openerp.com )
#
# Disclaimer: Many of the functions below borrow code from the
#   python-webdav library (http://code.google.com/p/pywebdav/ ),
#   which they import and override to suit OpenERP functionality.
# python-webdav was written by: Simon Pamies <s.pamies@banality.de>
#                               Christian Scholz <mrtopf@webdav.de>
#                               Vince Spicer <vince@vince.ca>
#
# WARNING: This program as such is intended to be used by professional
# programmers who take the whole responsability of assessing all potential
# consequences resulting from its eventual inadequacies and bugs
# End users who are looking for a ready-to-use solution with commercial
# garantees and support are strongly adviced to contract a Free Software
# Service Company
#
# This program is Free Software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 3
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
###############################################################################


import logging
import netsvc
from dav_fs import openerp_dav_handler
from tools.config import config
from DAV.WebDAVServer import DAVRequestHandler
from service import http_server
from service.websrv_lib import FixSendError, HttpOptions
from BaseHTTPServer import BaseHTTPRequestHandler
import urlparse
import urllib
import re
import time
from string import atoi
import addons
from DAV.utils import IfParser, TagList
from DAV.errors import DAV_Error, DAV_Forbidden, DAV_NotFound
from DAV.propfind import PROPFIND
# from DAV.constants import DAV_VERSION_1, DAV_VERSION_2
from xml.dom import minidom
from redirect import RedirectHTTPHandler

khtml_re = re.compile(r' KHTML/([0-9\.]+) ')

def OpenDAVConfig(**kw):
    class OpenDAV:
        def __init__(self, **kw):
            self.__dict__.update(**kw)

        def getboolean(self, word):
            return self.__dict__.get(word, False)

    class Config:
        DAV = OpenDAV(**kw)

    return Config()


class DAVHandler(HttpOptions, FixSendError, DAVRequestHandler):
    verbose = False
    _logger = logging.getLogger('webdav')
    protocol_version = 'HTTP/1.1'
    _HTTP_OPTIONS= { 'DAV' : ['1', '2'],
                    'Allow' : [ 'GET', 'HEAD', 'COPY', 'MOVE', 'POST', 'PUT',
                            'PROPFIND', 'PROPPATCH', 'OPTIONS', 'MKCOL',
                            'DELETE', 'TRACE', 'REPORT', ]
                    }

    def get_userinfo(self,user,pw):
        return False

    def _log(self, message):
        self._logger.debug(message)

    def handle(self):
        self._init_buffer()

    def finish(self):
        pass

    def get_db_from_path(self, uri):
        # interface class will handle all cases.
        res =  self.IFACE_CLASS.get_db(uri, allow_last=True)
        return res

    def setup(self):
        self.davpath = '/'+config.get_misc('webdav','vdir','webdav')
        addr, port = self.server.server_name, self.server.server_port
        server_proto = getattr(self.server,'proto', 'http').lower()
        try:
            if hasattr(self.request, 'getsockname'):
                addr, port = self.request.getsockname()
        except Exception, e:
            self.log_error("Cannot calculate own address: %s" , e)
        # Too early here to use self.headers
        self.baseuri = "%s://%s:%d/"% (server_proto, addr, port)
        self.IFACE_CLASS  = openerp_dav_handler(self, self.verbose)

    def copymove(self, CLASS):
        """ Our uri scheme removes the /webdav/ component from there, so we
        need to mangle the header, too.
        """
        up = urlparse.urlparse(urllib.unquote(self.headers['Destination']))
        if up.path.startswith(self.davpath):
            self.headers['Destination'] = up.path[len(self.davpath):]
        else:
            raise DAV_Forbidden("Not allowed to copy/move outside webdav path")
        # TODO: locks
        DAVRequestHandler.copymove(self, CLASS)

    def get_davpath(self):
        return self.davpath

    def log_message(self, format, *args):
        self._logger.debug(format % args)

    def log_error(self, format, *args):
        self._logger.warning(format % args)

    def _prep_OPTIONS(self, opts):
        ret = opts
        dc=self.IFACE_CLASS
        uri=urlparse.urljoin(self.get_baseuri(dc), self.path)
        uri=urllib.unquote(uri)
        try:
            ret = dc.prep_http_options(uri, opts)
        except DAV_Error, (ec,dd):
            pass
        except Exception,e:
            self.log_error("Error at options: %s", str(e))
            raise
        return ret

    def send_response(self, code, message=None):
        # the BufferingHttpServer will send Connection: close , while
        # the BaseHTTPRequestHandler will only accept int code.
        # workaround both of them.
        if self.command == 'PROPFIND' and int(code) == 404:
            kh = khtml_re.search(self.headers.get('User-Agent',''))
            if kh and (kh.group(1) < '4.5'):
                # There is an ugly bug in all khtml < 4.5.x, where the 404
                # response is treated as an immediate error, which would even
                # break the flow of a subsequent PUT request. At the same time,
                # the 200 response  (rather than 207 with content) is treated
                # as "path not exist", so we send this instead
                # https://bugs.kde.org/show_bug.cgi?id=166081
                code = 200
        BaseHTTPRequestHandler.send_response(self, int(code), message)

    def send_header(self, key, value):
        if key == 'Connection' and value == 'close':
            self.close_connection = 1
        DAVRequestHandler.send_header(self, key, value)

    def send_body(self, DATA, code = None, msg = None, desc = None, ctype='application/octet-stream', headers=None):
        if headers and 'Connection' in headers:
            pass
        elif self.request_version in ('HTTP/1.0', 'HTTP/0.9'):
            pass
        elif self.close_connection == 1: # close header already sent
            pass
        elif headers and self.headers.get('Connection',False) == 'Keep-Alive':
            headers['Connection'] = 'keep-alive'

        if headers is None:
            headers = {}

        DAVRequestHandler.send_body(self, DATA, code=code, msg=msg, desc=desc,
                    ctype=ctype, headers=headers)

    def do_PUT(self):
        dc=self.IFACE_CLASS
        uri=urlparse.urljoin(self.get_baseuri(dc), self.path)
        uri=urllib.unquote(uri)
        # Handle If-Match
        if self.headers.has_key('If-Match'):
            test = False
            etag = None

            for match in self.headers['If-Match'].split(','):
                if match == '*':
                    if dc.exists(uri):
                        test = True
                        break
                else:
                    if dc.match_prop(uri, match, "DAV:", "getetag"):
                        test = True
                        break
            if not test:
                self._get_body()
                self.send_status(412)
                return

        # Handle If-None-Match
        if self.headers.has_key('If-None-Match'):
            test = True
            etag = None
            for match in self.headers['If-None-Match'].split(','):
                if match == '*':
                    if dc.exists(uri):
                        test = False
                        break
                else:
                    if dc.match_prop(uri, match, "DAV:", "getetag"):
                        test = False
                        break
            if not test:
                self._get_body()
                self.send_status(412)
                return

        # Handle expect
        expect = self.headers.get('Expect', '')
        if (expect.lower() == '100-continue' and
                self.protocol_version >= 'HTTP/1.1' and
                self.request_version >= 'HTTP/1.1'):
            self.send_status(100)
            self._flush()

        # read the body
        body=self._get_body()

        # locked resources are not allowed to be overwritten
        if self._l_isLocked(uri):
            return self.send_body(None, '423', 'Locked', 'Locked')

        ct=None
        if self.headers.has_key("Content-Type"):
            ct=self.headers['Content-Type']
        try:
            location = dc.put(uri, body, ct)
        except DAV_Error, (ec,dd):
            self.log_error("Cannot PUT to %s: %s", uri, dd)
            return self.send_status(ec)

        headers = {}
        etag = None
        if location and isinstance(location, tuple):
            etag = location[1]
            location = location[0]
            # note that we have allowed for > 2 elems
        if location:
            headers['Location'] = location
        else:
            try:
                if not etag:
                    etag = dc.get_prop(location or uri, "DAV:", "getetag")
                if etag:
                    headers['ETag'] = str(etag)
            except Exception:
                pass

        self.send_body(None, '201', 'Created', '', headers=headers)

    def _get_body(self):
        body = None
        if self.headers.has_key("Content-Length"):
            l=self.headers['Content-Length']
            body=self.rfile.read(atoi(l))
        return body

    def do_DELETE(self):
        try:
            DAVRequestHandler.do_DELETE(self)
        except DAV_Error, (ec, dd):
            return self.send_status(ec)

    def do_UNLOCK(self):
        """ Unlocks given resource """

        dc = self.IFACE_CLASS
        self.log_message('UNLOCKing resource %s' % self.headers)

        uri = urlparse.urljoin(self.get_baseuri(dc), self.path)
        uri = urllib.unquote(uri)

        token = self.headers.get('Lock-Token', False)
        if token:
            token = token.strip()
            if token[0] == '<' and token[-1] == '>':
                token = token[1:-1]
            else:
                token = False

        if not token:
            return self.send_status(400, 'Bad lock token')

        try:
            res = dc.unlock(uri, token)
        except DAV_Error, (ec, dd):
            return self.send_status(ec, dd)
        
        if res == True:
            self.send_body(None, '204', 'OK', 'Resource unlocked.')
        else:
            # We just differentiate the description, for debugging purposes
            self.send_body(None, '204', 'OK', 'Resource not locked.')

    def do_LOCK(self):
        """ Attempt to place a lock on the given resource.
        """

        dc = self.IFACE_CLASS
        lock_data = {}

        self.log_message('LOCKing resource %s' % self.headers)

        body = None
        if self.headers.has_key('Content-Length'):
            l = self.headers['Content-Length']
            body = self.rfile.read(atoi(l))

        depth = self.headers.get('Depth', 'infinity')

        uri = urlparse.urljoin(self.get_baseuri(dc), self.path)
        uri = urllib.unquote(uri)
        self.log_message('do_LOCK: uri = %s' % uri)

        ifheader = self.headers.get('If')

        if ifheader:
            ldif = IfParser(ifheader)
            if isinstance(ldif, list):
                if len(ldif) !=1 or (not isinstance(ldif[0], TagList)) \
                        or len(ldif[0].list) != 1:
                    raise DAV_Error(400, "Cannot accept multiple tokens")
                ldif = ldif[0].list[0]
                if ldif[0] == '<' and ldif[-1] == '>':
                    ldif = ldif[1:-1]

            lock_data['token'] = ldif

        if not body:
            lock_data['refresh'] = True
        else:
            lock_data['refresh'] = False
            lock_data.update(self._lock_unlock_parse(body))

        if lock_data['refresh'] and not lock_data.get('token', False):
            raise DAV_Error(400, 'Lock refresh must specify token')

        lock_data['depth'] = depth

        try:
            created, data, lock_token = dc.lock(uri, lock_data)
        except DAV_Error, (ec, dd):
            return self.send_status(ec, dd)

        headers = {}
        if not lock_data['refresh']:
            headers['Lock-Token'] = '<%s>' % lock_token

        if created:
            self.send_body(data, '201', 'Created',  ctype='text/xml', headers=headers)
        else:
            self.send_body(data, '200', 'OK', ctype='text/xml', headers=headers)

    def _lock_unlock_parse(self, body):
        # Override the python-webdav function, with some improvements
        # Unlike the py-webdav one, we also parse the owner minidom elements into
        # pure pythonic struct.
        doc = minidom.parseString(body)

        data = {}
        owners = []
        for info in doc.getElementsByTagNameNS('DAV:', 'lockinfo'):
            for scope in info.getElementsByTagNameNS('DAV:', 'lockscope'):
                for scc in scope.childNodes:
                    if scc.nodeType == info.ELEMENT_NODE \
                            and scc.namespaceURI == 'DAV:':
                        data['lockscope'] = scc.localName
                        break
            for ltype in info.getElementsByTagNameNS('DAV:', 'locktype'):
                for ltc in ltype.childNodes:
                    if ltc.nodeType == info.ELEMENT_NODE \
                            and ltc.namespaceURI == 'DAV:':
                        data['locktype'] = ltc.localName
                        break
            for own in info.getElementsByTagNameNS('DAV:', 'owner'):
                for ono in own.childNodes:
                    if ono.nodeType == info.TEXT_NODE:
                        if ono.data:
                            owners.append(ono.data)
                    elif ono.nodeType == info.ELEMENT_NODE \
                            and ono.namespaceURI == 'DAV:' \
                            and ono.localName == 'href':
                        href = ''
                        for hno in ono.childNodes:
                            if hno.nodeType == info.TEXT_NODE:
                                href += hno.data
                        owners.append(('href','DAV:', href))

            if len(owners) == 1:
                data['lockowner'] = owners[0]
            elif not owners:
                pass
            else:
                data['lockowner'] = owners
        return data

from service.http_server import reg_http_service,OpenERPAuthProvider

class DAVAuthProvider(OpenERPAuthProvider):
    def authenticate(self, db, user, passwd, client_address):
        """ authenticate, but also allow the False db, meaning to skip
            authentication when no db is specified.
        """
        if db is False:
            return True
        return OpenERPAuthProvider.authenticate(self, db, user, passwd, client_address)


class dummy_dav_interface(object):
    """ Dummy dav interface """
    verbose = True

    PROPS={"DAV:" : ('creationdate',
                     'displayname',
                     'getlastmodified',
                     'resourcetype',
                     ),
           }

    M_NS={"DAV:" : "_get_dav", }

    def __init__(self, parent):
        self.parent = parent

    def get_propnames(self,uri):
        return self.PROPS

    def get_prop(self,uri,ns,propname):
        if self.M_NS.has_key(ns):
            prefix=self.M_NS[ns]
        else:
            raise DAV_NotFound
        mname=prefix+"_"+propname.replace('-', '_')
        try:
            m=getattr(self,mname)
            r=m(uri)
            return r
        except AttributeError:
            raise DAV_NotFound

    def get_data(self, uri, range=None):
        raise DAV_NotFound

    def _get_dav_creationdate(self,uri):
        return time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime())

    def _get_dav_getlastmodified(self,uri):
        return time.strftime("%a, %d %b %Y %H:%M:%S GMT", time.gmtime())

    def _get_dav_displayname(self, uri):
        return uri

    def _get_dav_resourcetype(self, uri):
        return ('collection', 'DAV:')

    def exists(self, uri):
        """ return 1 or None depending on if a resource exists """
        uri2 = uri.split('/')
        if len(uri2) < 3:
            return True
        logging.getLogger('webdav').debug("Requested uri: %s", uri)
        return None # no

    def is_collection(self, uri):
        """ return 1 or None depending on if a resource is a collection """
        return None # no

class DAVStaticHandler(http_server.StaticHTTPHandler):
    """ A variant of the Static handler, which will serve dummy DAV requests
    """
    verbose = False
    protocol_version = 'HTTP/1.1'
    _HTTP_OPTIONS= { 'DAV' : ['1', '2'],
                    'Allow' : [ 'GET', 'HEAD',
                            'PROPFIND', 'OPTIONS', 'REPORT', ]
                    }

    def send_body(self, content, code, message='OK', content_type='text/xml'):
        self.send_response(int(code), message)
        self.send_header("Content-Type", content_type)
        # self.send_header('Connection', 'close')
        self.send_header('Content-Length', len(content) or 0)
        self.end_headers()
        if hasattr(self, '_flush'):
            self._flush()
        
        if self.command != 'HEAD':
            self.wfile.write(content)

    def do_PROPFIND(self):
        """Answer to PROPFIND with generic data.
        
        A rough copy of python-webdav's do_PROPFIND, but hacked to work
        statically.
        """

        dc = dummy_dav_interface(self)

        # read the body containing the xml request
        # iff there is no body then this is an ALLPROP request
        body = None
        if self.headers.has_key('Content-Length'):
            l = self.headers['Content-Length']
            body = self.rfile.read(atoi(l))

        path = self.path.rstrip('/')
        uri = urllib.unquote(path)

        pf = PROPFIND(uri, dc, self.headers.get('Depth', 'infinity'), body)

        try:
            DATA = '%s\n' % pf.createResponse()
        except DAV_Error, (ec,dd):
            return self.send_error(ec,dd)
        except Exception:
            self.log_exception("Cannot PROPFIND")
            raise

        # work around MSIE DAV bug for creation and modified date
        # taken from Resource.py @ Zope webdav
        if (self.headers.get('User-Agent') ==
            'Microsoft Data Access Internet Publishing Provider DAV 1.1'):
            DATA = DATA.replace('<ns0:getlastmodified xmlns:ns0="DAV:">',
                                    '<ns0:getlastmodified xmlns:n="DAV:" xmlns:b="urn:uuid:c2f41010-65b3-11d1-a29f-00aa00c14882/" b:dt="dateTime.rfc1123">')
            DATA = DATA.replace('<ns0:creationdate xmlns:ns0="DAV:">',
                                    '<ns0:creationdate xmlns:n="DAV:" xmlns:b="urn:uuid:c2f41010-65b3-11d1-a29f-00aa00c14882/" b:dt="dateTime.tz">')

        self.send_body(DATA, '207','Multi-Status','Multiple responses')

    def not_get_baseuri(self):
        baseuri = '/'
        if self.headers.has_key('Host'):
            uparts = list(urlparse.urlparse('/'))
            uparts[1] = self.headers['Host']
            baseuri = urlparse.urlunparse(uparts)
        return baseuri

    def get_davpath(self):
        return ''


try:

    if (config.get_misc('webdav','enable',True)):
        directory = '/'+config.get_misc('webdav','vdir','webdav')
        handler = DAVHandler
        verbose = config.get_misc('webdav','verbose',True)
        handler.debug = config.get_misc('webdav','debug',True)
        _dc = { 'verbose' : verbose,
                'directory' : directory,
                'lockemulation' : True,
                }

        conf = OpenDAVConfig(**_dc)
        handler._config = conf
        reg_http_service(directory, DAVHandler, DAVAuthProvider)
        logging.getLogger('webdav').info("WebDAV service registered at path: %s/ "% directory)
        
        if not (config.get_misc('webdav', 'no_root_hack', False)):
            # Now, replace the static http handler with the dav-enabled one.
            # If a static-http service has been specified for our server, then
            # read its configuration and use that dir_path.
            # NOTE: this will _break_ any other service that would be registered
            # at the root path in future.
            base_path = False
            if config.get_misc('static-http','enable', False):
                base_path = config.get_misc('static-http', 'base_path', '/')
            if base_path and base_path == '/':
                dir_path = config.get_misc('static-http', 'dir_path', False)
            else:
                dir_path = addons.get_module_resource('document_webdav','public_html')
                # an _ugly_ hack: we put that dir back in tools.config.misc, so that
                # the StaticHttpHandler can find its dir_path.
                config.misc.setdefault('static-http',{})['dir_path'] = dir_path
    
            reg_http_service('/', DAVStaticHandler)

except Exception, e:
    logging.getLogger('webdav').error('Cannot launch webdav: %s' % e)


def init_well_known():
    reps = RedirectHTTPHandler.redirect_paths

    num_svcs = config.get_misc('http-well-known', 'num_services', '0')

    for nsv in range(1, int(num_svcs)+1):
        uri = config.get_misc('http-well-known', 'service_%d' % nsv, False)
        path = config.get_misc('http-well-known', 'path_%d' % nsv, False)
        if not (uri and path):
            continue
        reps['/'+uri] = path

    if int(num_svcs):
        reg_http_service('/.well-known', RedirectHTTPHandler)

init_well_known()

class PrincipalsRedirect(RedirectHTTPHandler):
    redirect_paths = {}
    
    def _find_redirect(self):
        for b, r in self.redirect_paths.items():
            if self.path.startswith(b):
                return r + self.path[len(b):]
        return False

def init_principals_redirect():
    """ Some devices like the iPhone will look under /principals/users/xxx for 
    the user's properties. In OpenERP we _cannot_ have a stray /principals/...
    working path, since we have a database path and the /webdav/ component. So,
    the best solution is to redirect the url with 301. Luckily, it does work in
    the device. The trick is that we need to hard-code the database to use, either
    the one centrally defined in the config, or a "forced" one in the webdav
    section.
    """
    dbname = config.get_misc('webdav', 'principal_dbname', False)
    if (not dbname) and not config.get_misc('webdav', 'no_principals_redirect', False):
        dbname = config.get('db_name', False)
    if dbname:
        PrincipalsRedirect.redirect_paths[''] = '/webdav/%s/principals' % dbname
        reg_http_service('/principals', PrincipalsRedirect)
        logging.getLogger("web-services").info(
                "Registered HTTP redirect handler for /principals to the %s db.",
                dbname)

init_principals_redirect()

#eof




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