#!/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 ipaserver.install.dsinstance import config_dirname, realm_to_serverid
    from ipaserver.install.installutils import is_ipa_configured
    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 is_ipa_configured():
        # 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 is_dirsrv_debugging_enabled():
    """
    Check the IPA and PKI-CA 389-ds instances to see if debugging is
    enabled. If so we suppress that in our output.

    returns True or False
    """
    debugging = False
    serverid = realm_to_serverid(api.env.realm)
    for dse in ['/etc/dirsrv/slapd-PKI-IPA/', config_dirname(serverid)]:
        try:
            fd = open(dse + 'dse.ldif', 'r')
        except IOError:
            continue
        lines = fd.readlines()
        fd.close()
        for line in lines:
            if line.lower().startswith('nsslapd-errorlog-level'):
                (option, value) = line.split(':')
                if int(value) > 0:
                    debugging = True

    return debugging

def get_capture_output(service, debug):
    """
    We want to display any output of a start/stop command with the
    exception of 389-ds when debugging is enabled because it outputs
    tons and tons of information.
    """
    if service == 'dirsrv' and not debug and is_dirsrv_debugging_enabled():
        print '    debugging enabled, suppressing output.'
        return True
    else:
        return False

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(options):
    try:
        print "Starting Directory Service"
        service.start('dirsrv', capture_output=get_capture_output('dirsrv', options.debug))
    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=get_capture_output(svc_name, options.debug))
        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(options):
    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(options):
    try:
        print "Restarting Directory Service"
        service.restart('dirsrv', capture_output=get_capture_output('dirsrv', options.debug))
    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=get_capture_output(svc_name, options.debug))
        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(options):
    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(options)
    elif args[0].lower() == "stop":
        ipa_stop(options)
    elif args[0].lower() == "restart":
        ipa_restart(options)
    elif args[0].lower() == "status":
        ipa_status(options)

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)