#!/usr/bin/python
# Authors: Rob Crittenden <rcritten@redhat.com>
# Authors: Simo Sorce <ssorce@redhat.com>
#
# Copyright (C) 2008  Red Hat
# see file 'COPYING' for use and warranty information
#
# 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, see <http://www.gnu.org/licenses/>.
#

import sys
try:
    from optparse import OptionParser
    from ipapython import ipautil, config
    from ipaserver.install import installutils
    from ipaserver.install.ldapupdate import LDAPUpdate, BadSyntax
    from ipaserver.plugins.ldap2 import ldap2
    from ipalib import api, errors
    import logging
except ImportError:
    print >> sys.stderr, """\
There was a problem importing one of the required Python modules. The
error was:

    %s
""" % sys.exc_value
    sys.exit(1)

compat_dn = "cn=Schema Compatibility,cn=plugins,cn=config"
nis_config_dn = "cn=NIS Server,cn=plugins,cn=config"

def parse_options():
    usage = "%prog [options] <enable|disable>\n"
    usage += "%prog [options]\n"
    parser = OptionParser(usage=usage, formatter=config.IPAFormatter())

    parser.add_option("-d", "--debug", action="store_true", dest="debug",
                      help="Display debugging information about the update(s)")
    parser.add_option("-y", dest="password",
                      help="File containing the Directory Manager password")

    config.add_standard_options(parser)
    options, args = parser.parse_args()

    config.init_config(options)

    return options, args

def get_dirman_password():
    """Prompt the user for the Directory Manager password and verify its
       correctness.
    """
    password = installutils.read_password("Directory Manager", confirm=False, validate=False)

    return password

def get_entry(dn, conn):
    """
    Return the entry for the given DN. If the entry is not found return
    None.
    """
    entry = None
    try:
        (dn, entry) = conn.get_entry(dn, normalize=False)
    except errors.NotFound:
        pass
    return entry

def main():
    retval = 0
    loglevel = logging.ERROR
    files = ['/usr/share/ipa/schema_compat.uldif']

    options, args = parse_options()
    if options.debug:
        loglevel = logging.DEBUG

    if len(args) != 1:
        sys.exit("You must specify one action, either enable or disable")
    elif args[0] != "enable" and args[0] != "disable" and args[0] != "status":
        sys.exit("Unrecognized action [" + args[0] + "]")

    logging.basicConfig(level=loglevel,
                        format='%(levelname)s %(message)s')

    dirman_password = ""
    if options.password:
        pw = ipautil.template_file(options.password, [])
        dirman_password = pw.strip()
    else:
        dirman_password = get_dirman_password()
        if dirman_password is None:
            sys.exit("\nDirectory Manager password required")

    api.bootstrap(context='cli', debug=options.debug)
    api.finalize()

    conn = None
    try:
        try:
            conn = ldap2(shared_instance=False, base_dn='')
            conn.connect(
                bind_dn='cn=directory manager', bind_pw=dirman_password
            )
        except errors.ExecutionError, lde:
            sys.exit("An error occurred while connecting to the server.\n%s\n" % str(lde))
        except errors.ACIError, e:
            sys.exit("Authentication failed: %s" % e.info)

        if args[0] == "status":
            entry = None
            try:
                entry = get_entry(compat_dn, conn)
                if entry is not None and entry.get('nsslapd-pluginenabled', [''])[0].lower() == 'on':
                    print "Plugin Enabled"
                else:
                    print "Plugin Disabled"
            except errors.LDAPError, lde:
                print "An error occurred while talking to the server."
                print lde

        if args[0] == "enable":
            entry = None
            try:
                entry = get_entry(compat_dn, conn)
                if entry is not None and entry.get('nsslapd-pluginenabled', [''])[0].lower() == 'on':
                    print "Plugin already Enabled"
                    retval = 2
                else:
                    print "Enabling plugin"

                    if entry is None:
                        ld = LDAPUpdate(dm_password=dirman_password, sub_dict={})
                        if not ld.update(files):
                            print "Updating Directory Server failed."
                            retval = 1
                    else:
                        mod = {'nsslapd-pluginenabled': 'on'}
                        conn.update_entry(compat_dn, mod, normalize=False)
            except errors.ExecutionError, lde:
                print "An error occurred while talking to the server."
                print lde
                retval = 1

        elif args[0] == "disable":
            entry = None
            try:
                entry = get_entry(nis_config_dn, conn)
                # We can't disable schema compat if the NIS plugin is enabled
                if entry is not None and entry.get('nsslapd-pluginenabled', [''])[0].lower() == 'on':
                    print >>sys.stderr, "The NIS plugin is configured, cannot disable compatibility."
                    print >>sys.stderr, "Run 'ipa-nis-manage disable' first."
                    retval = 2
            except errors.ExecutionError, lde:
                print "An error occurred while talking to the server."
                print lde
                retval = 1

            if retval == 0:
                entry = None
                try:
                    entry = get_entry(compat_dn, conn)
                    if entry is None or entry.get('nsslapd-pluginenabled', [''])[0].lower() == 'off':
                        print "Plugin is already disabled"
                        retval = 2
                    else:
                        print "Disabling plugin"

                        mod = {'nsslapd-pluginenabled': 'off'}
                        conn.update_entry(compat_dn, mod, normalize=False)
                except errors.DatabaseError, dbe:
                    print "An error occurred while talking to the server."
                    print dbe
                    retval = 1
                except errors.ExecutionError, lde:
                    print "An error occurred while talking to the server."
                    print lde
                    retval = 1

        else:
            retval = 1

        if retval == 0:
            print "This setting will not take effect until you restart Directory Server."

    finally:
        if conn and conn.isconnected():
            conn.disconnect()

    return retval

try:
    if __name__ == "__main__":
        sys.exit(main())
except BadSyntax, e:
    print "There is a syntax error in this update file:"
    print "  %s" % e
    sys.exit(1)
except RuntimeError, e:
    print "%s" % e
    sys.exit(1)
except SystemExit, e:
    sys.exit(e)
except KeyboardInterrupt, e:
    sys.exit(1)
except config.IPAConfigError, e:
    print "An IPA server to update cannot be found. Has one been configured yet?"
    print "The error was: %s" % e
    sys.exit(1)
except errors.LDAPError, e:
    print "An error occurred while performing operations: %s" % e
    sys.exit(1)
