# passwd.py - lookup functions for user account information
#
# Copyright (C) 2010, 2011 Arthur de Jong
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301 USA

import ldap
import ldap.filter

import constants
import common


attmap = common.Attributes(uid='uid',
                           userPassword='"*"',
                           uidNumber='uidNumber',
                           gidNumber='gidNumber',
                           gecos='"${gecos:-$cn}"',
                           homeDirectory='homeDirectory',
                           loginShell='loginShell',
                           objectClass='objectClass')
filter = '(objectClass=posixAccount)'
bases = ( 'ou=people,dc=test,dc=tld', )


class PasswdRequest(common.Request):

    def write(self, dn, attributes, parameters):
        # get uid attribute and check against requested user name
        names = attributes['uid']
        if 'uid' in parameters:
            if parameters['uid'] not in names:
                return
            names = ( parameters['uid'], )
        # get user password entry
        if 'shadowAccount' in attributes['objectClass']:
            passwd = 'x'
        else:
            passwd = attributes['userPassword'][0]
        # get numeric user and group ids
        uids = ( parameters['uidNumber'], ) if 'uidNumber' in parameters else attributes['uidNumber']
        uids = [ int(x) for x in uids ]
        # get other passwd properties
        gid = int(attributes['gidNumber'][0])
        gecos = attributes['gecos'][0]
        home = attributes['homeDirectory'][0]
        shell = attributes['loginShell'][0]
        # write results
        for name in names:
            if not common.isvalidname(name):
                print 'Warning: passwd entry %s contains invalid user name: "%s"' % ( dn, name )
            else:
                for uid in uids:
                    self.fp.write_int32(constants.NSLCD_RESULT_BEGIN)
                    self.fp.write_string(name)
                    self.fp.write_string(passwd)
                    self.fp.write_uid_t(uid)
                    self.fp.write_gid_t(gid)
                    self.fp.write_string(gecos)
                    self.fp.write_string(home)
                    self.fp.write_string(shell)


class PasswdByNameRequest(PasswdRequest):

    action = constants.NSLCD_ACTION_PASSWD_BYNAME

    def read_parameters(self, fp):
        name = fp.read_string()
        common.validate_name(name)
        return dict(uid=name)


class PasswdByUidRequest(PasswdRequest):

    action = constants.NSLCD_ACTION_PASSWD_BYUID

    def read_parameters(self, fp):
        return dict(uidNumber=fp.read_uid_t())


class PasswdAllRequest(PasswdRequest):

    action = constants.NSLCD_ACTION_PASSWD_ALL


# FIXME: have something in common that does this
def do_search(conn, flt=None, base=None):
    mybases = ( base, ) if base else bases
    flt = flt or filter
    import cfg
    # perform a search for each search base
    for base in mybases:
        # do the LDAP search
        try:
            scope = locals().get('scope', cfg.scope)
            res = conn.search_s(base, scope, flt, [attmap['uid']])
            for entry in res:
                if entry[0]:
                    yield entry
        except ldap.NO_SUCH_OBJECT:
            # FIXME: log message
            pass

def uid2entry(conn, uid):
    """Look up the user by uid and return the LDAP entry or None if the user
    was not found."""
    myfilter = '(&%s(%s=%s))' % ( filter,
                  attmap['uid'], ldap.filter.escape_filter_chars(uid) )
    for dn, attributes in do_search(conn, myfilter):
        if uid in attributes[attmap['uid']]:
            return dn, attributes

def uid2dn(conn, uid):
    """Look up the user by uid and return the DN or None if the user was
    not found."""
    x = uid2entry(conn, uid)
    if x is not None:
        return x[0]

# FIXME: use cache of dn2uid and try to use DN to get uid attribute

def dn2uid(conn, dn):
    """Look up the user by dn and return a uid or None if the user was
    not found."""
    try:
        for dn, attributes in do_search(conn, base=dn):
            return attributes[attmap['uid']][0]
    except ldap.NO_SUCH_OBJECT:
        return None