#!/usr/bin/python
# Authors: Simo Sorce <ssorce@redhat.com>
#
# Copyright (C) 2008-2010  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:
    import os
    from ipaserver.install import service
    from ipapython import sysrestore
    from ipapython import config
    from ipalib import api, errors
    from ipalib.dn import DN
    import logging
    import ldap
    import ldap.sasl
    import socket
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)

SASL_EXTERNAL = ldap.sasl.sasl({}, 'EXTERNAL')

class IpactlError(StandardError):
    def __init__(self, msg = '', rval = 1):
        self.msg = msg
        self.rval = rval

    def __str__(self):
        return self.msg

def check_IPA_configuration():
    if not sysrestore.FileStore('/var/lib/ipa/sysrestore').has_files():
        # LSB status code 6: program is not configured
        raise IpactlError("IPA is not configured " +
                          "(see man pages of ipa-server-install for help)", 6)

def parse_options():
    usage = "%prog start|stop|restart|status\n"
    parser = config.IPAOptionParser(usage=usage,
                                    formatter=config.IPAFormatter())

    parser.add_option("-d", "--debug", action="store_true", dest="debug",
                      help="Display debugging information")

    options, args = parser.parse_args()
    safe_options = parser.get_safe_opts(options)

    return safe_options, options, args

def emit_err(err):
    sys.stderr.write(err + '\n')

def get_config():
    base = "cn=%s,cn=masters,cn=ipa,cn=etc,%s" % (api.env.host,
                                                  api.env.basedn)
    srcfilter = '(ipaConfigString=enabledService)'
    attrs = ['cn', 'ipaConfigString']

    try:
        con = ldap.initialize(api.env.ldap_uri)
        con.sasl_interactive_bind_s('', SASL_EXTERNAL)
        res = con.search_st(base,
                            ldap.SCOPE_SUBTREE,
                            filterstr=srcfilter,
                            attrlist=attrs,
                            timeout=10)
    except ldap.SERVER_DOWN, e:
        # LSB status code 3: program is not running
        raise IpactlError("Failed to get list of services to probe status:\n" +
                          "Directory Server is stopped", 3)
    except ldap.NO_SUCH_OBJECT:
        masters_list = []
        dn = str(DN('cn=masters,cn=ipa,cn=etc,%s' % api.env.basedn))
        attrs = ['cn']
        try:
            entries = con.search_s(dn,
                                    ldap.SCOPE_ONELEVEL,
                                    attrlist=attrs,)
        except Exception, e:
            masters_list.append("No master found because of error: %s" % str(e))
        else:
            for dn,master_entry in entries:
                masters_list.append(master_entry.get('cn', [None])[0])

        masters = "\n".join(masters_list)

        raise IpactlError("Failed to get list of services to probe status!\n"
                          "Configured hostname '%s' does not match any master server in LDAP:\n%s"
                          % (api.env.host, masters))
    except Exception, e:
        raise IpactlError("Unknown error when retrieving list of services from LDAP: " + str(e))

    svc_list = []

    for entry in res:
        name = entry[1]['cn'][0]
        for p in entry[1]['ipaConfigString']:
            if p.startswith('startOrder '):
                order = p.split()[1]
        svc_list.append((order, name))

    return svc_list

def ipa_start():
    try:
        print "Starting Directory Service"
        service.start('dirsrv', capture_output=False)
    except Exception, e:
        raise IpactlError("Failed to start Directory Service: " + str(e))

    svc_list = []
    try:
        svc_list = get_config()
    except Exception, e:
        emit_err("Failed to read data from Directory Service: " + str(e))
        emit_err("Shutting down")
        try:
            service.stop('dirsrv', capture_output=False)
        except:
            pass
        if isinstance(e, IpactlError):
            # do not display any other error message
            raise IpactlError(None, e.rval)
        else:
            raise IpactlError(None)

    if len(svc_list) == 0:
        # no service to stop
        return

    for (order, svc) in sorted(svc_list):
        svc_name = service.SERVICE_LIST[svc][0]
        try:
            print "Starting %s Service" % svc
            service.start(svc_name, capture_output=False)
        except:
            emit_err("Failed to start %s Service" % svc)
            emit_err("Shutting down")
            for (order, svc) in sorted(svc_list):
                svc_name = service.SERVICE_LIST[svc][0]
                try:
                    service.stop(svc_name, capture_output=False)
                except:
                    pass
            try:
                service.stop('dirsrv', capture_output=False)
            except:
                pass
            raise IpactlError("Aborting ipactl")

def ipa_stop():
    svc_list = []
    try:
        svc_list = get_config()
    except Exception, e:
        # ok if dirsrv died this may fail, so let's try to quickly restart it
        # and see if we can get anything. If not throw our hands up and just
        # exit
        try:
            service.start('dirsrv', capture_output=False)
            svc_list = get_config()
        except Exception, e:
            emit_err("Failed to read data from Directory Service: " + str(e))
            emit_err("Shutting down")
            try:
                # just try to stop it, do not read a result
                service.stop('dirsrv')
            finally:
                raise IpactlError(None)

    if len(svc_list) == 0:
        # no service to stop
        return

    for (order, svc) in sorted(svc_list, reverse=True):
        svc_name = service.SERVICE_LIST[svc][0]
        try:
            print "Stopping %s Service" % svc
            service.stop(svc_name, capture_output=False)
        except:
            emit_err("Failed to stop %s Service" % svc)

    try:
        print "Stopping Directory Service"
        service.stop('dirsrv', capture_output=False)
    except:
        raise IpactlError("Failed to stop Directory Service")


def ipa_restart():
    try:
        print "Restarting Directory Service"
        service.restart('dirsrv', capture_output=False)
    except Exception, e:
        raise IpactlError("Failed to restart Directory Service: " + str(e))

    svc_list = []
    try:
        svc_list = get_config()
    except Exception, e:
        emit_err("Failed to read data from Directory Service: " + str(e))
        emit_err("Shutting down")
        try:
            service.stop('dirsrv', capture_output=False)
        except:
            pass
        if isinstance(e, IpactlError):
            # do not display any other error message
            raise IpactlError(None, e.rval)
        else:
            raise IpactlError(None)

    if len(svc_list) == 0:
        # no service to stop
        return

    for (order, svc) in sorted(svc_list):
        svc_name = service.SERVICE_LIST[svc][0]
        try:
            print "Restarting %s Service" % svc
            service.restart(svc_name, capture_output=False)
        except:
            emit_err("Failed to restart %s Service" % svc)
            emit_err("Shutting down")
            for (order, svc) in sorted(svc_list):
                svc_name = service.SERVICE_LIST[svc][0]
                try:
                    service.stop(svc_name, capture_output=False)
                except:
                    pass
            try:
                service.stop('dirsrv', capture_output=False)
            except:
                pass
            raise IpactlError("Aborting ipactl")

def ipa_status():
    try:
        if service.is_running('dirsrv'):
            print "Directory Service: RUNNING"
        else:
            print "Directory Service: STOPPED"
    except:
        raise IpactlError("Failed to get Directory Service status")

    svc_list = []
    try:
        svc_list = get_config()
    except IpactlError, e:
        raise e
    except Exception, e:
        raise IpactlError("Failed to get list of services to probe status: " + str(e))

    if len(svc_list) == 0:
        return

    for (order, svc) in sorted(svc_list):
        svc_name = service.SERVICE_LIST[svc][0]
        try:
            if service.is_running(svc_name):
                print "%s Service: RUNNING" % svc
            else:
                print "%s Service: STOPPED" % svc
        except:
            emit_err("Failed to get %s Service status" % svc)

def main():
    if not os.getegid() == 0:
        # LSB status code 4: user had insufficient privilege
        raise IpactlError("You must be root to run ipactl.", 4)

    safe_options, options, args = parse_options()

    if len(args) != 1:
        # LSB status code 2: invalid or excess argument(s)
        raise IpactlError("You must specify one action", 2)
    elif args[0] != "start" and args[0] != "stop" and args[0] != "restart" and args[0] != "status":
        raise IpactlError("Unrecognized action [" + args[0] + "]", 2)

    # check if IPA is configured at all
    try:
        check_IPA_configuration()
    except IpactlError, e:
        if args[0].lower() == "status":
            # Different LSB return code for status command:
            # 4 - program or service status is unknown
            # This should differentiate uninstalled IPA from status
            # code 3 - program is not running
            e.rval = 4
            raise e
        else:
            raise e

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

    if '.' not in api.env.host:
        raise IpactlError("Invalid hostname '%s' in IPA configuration!\n"
                          "The hostname must be fully-qualified" % api.env.host)

    if args[0].lower() == "start":
        ipa_start()
    elif args[0].lower() == "stop":
        ipa_stop()
    elif args[0].lower() == "restart":
        ipa_restart()
    elif args[0].lower() == "status":
        ipa_status()

try:
    if __name__ == "__main__":
        sys.exit(main())
except IpactlError, e:
    if e.msg:
        emit_err(e.msg)
    sys.exit(e.rval)
except RuntimeError, e:
    emit_err("%s" % e)
    sys.exit(1)
except SystemExit, e:
    sys.exit(e)
except KeyboardInterrupt, e:
    sys.exit(1)