#!/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
import os
import json

import ldapurl

from ipaserver.install import service, installutils
from ipaserver.install.dsinstance import config_dirname, realm_to_serverid
from ipaserver.install.installutils import is_ipa_configured, ScriptError
from ipalib import api, errors
from ipapython.ipaldap import IPAdmin
from ipapython.ipautil import wait_for_open_ports, wait_for_open_socket
from ipapython import services as ipaservices
from ipapython import config, dogtag
from ipapython.dn import DN

class IpactlError(ScriptError):
    pass

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 389-ds instance 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)
    dselist = [config_dirname(serverid)]
    for dse in dselist:
        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(dirsrv):
    base = DN(('cn', api.env.host), ('cn', 'masters'), ('cn', 'ipa'), ('cn', 'etc'), api.env.basedn)
    srcfilter = '(ipaConfigString=enabledService)'
    attrs = ['cn', 'ipaConfigString']
    if not dirsrv.is_running():
        raise IpactlError("Failed to get list of services to probe status:\n" +
                          "Directory Server is stopped", 3)

    try:
        # The start/restart functions already wait for the server to be
        # started. What we are doing with this wait is really checking to see
        # if the server is listening at all.
        lurl = ldapurl.LDAPUrl(api.env.ldap_uri)
        if lurl.urlscheme == 'ldapi':
            wait_for_open_socket(lurl.hostport, timeout=api.env.startup_timeout)
        else:
            (host, port) = lurl.hostport.split(':')
            wait_for_open_ports(host, [int(port)], timeout=api.env.startup_timeout)
        con = IPAdmin(ldap_uri=api.env.ldap_uri)
        con.do_external_bind()
        res, truncated = con.find_entries(
            filter=srcfilter,
            attrs_list=attrs,
            base_dn=base,
            scope=con.SCOPE_SUBTREE,
            time_limit=10)
        if truncated:
            raise errors.LimitsExceeded()
    except errors.NetworkError:
        # 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 errors.NotFound:
        masters_list = []
        dn = DN(('cn', 'masters'), ('cn', 'ipa'), ('cn', 'etc'), api.env.basedn)
        attrs = ['cn']
        try:
            entries = con.get_entries(dn, con.SCOPE_ONELEVEL, attrs_list=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.single_value('cn'))

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

    ordered_list = []
    for (order, svc) in sorted(svc_list):
        if svc in service.SERVICE_LIST:
            ordered_list.append(service.SERVICE_LIST[svc][0])
    return ordered_list

def get_config_from_file():

    svc_list = []

    try:
        f = open(ipaservices.get_svc_list_file(), 'r')
        svc_list = json.load(f)
    except Exception, e:
        raise IpactlError("Unknown error when retrieving list of services from file: " + str(e))

    # the framework can start/stop a number of related services we are not
    # authoritative for, so filter the list through SERVICES_LIST and order it
    # accordingly too.

    def_svc_list = []
    for svc in service.SERVICE_LIST:
        s = service.SERVICE_LIST[svc]
        def_svc_list.append([s[1], s[0]])

    ordered_list = []
    for (order, svc) in sorted(def_svc_list):
        if svc in svc_list:
            ordered_list.append(svc)

    return ordered_list

def ipa_start(options):

    if os.path.isfile(ipaservices.get_svc_list_file()):
        emit_err("Existing service file detected!")
        emit_err("Assuming stale, cleaning and proceeding")
        # remove file with list of started services
        # This is ok as systemd will just skip services
        # that are already running and just return, so that the
        # stop() method of the base class will simply fill in the
        # service file again
        os.unlink(ipaservices.SVC_LIST_FILE)

    dirsrv = ipaservices.knownservices.dirsrv
    try:
        print "Starting Directory Service"
        dirsrv.start(capture_output=get_capture_output('dirsrv', options.debug))
    except Exception, e:
        raise IpactlError("Failed to start Directory Service: " + str(e))

    ldap_list = []
    try:
        svc_list = get_config(dirsrv)
    except Exception, e:
        emit_err("Failed to data from service file: " + str(e))
        emit_err("Shutting down")
        try:
            dirsrv.stop(capture_output=False)
        except:
            pass
        if isinstance(e, IpactlError):
            # do not display any other error message
            raise IpactlError(rval=e.rval)
        else:
            raise IpactlError()

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

    for svc in svc_list:
        svchandle = ipaservices.service(svc)
        try:
            print "Starting %s Service" % svc
            svchandle.start(capture_output=get_capture_output(svc, options.debug))
        except:
            emit_err("Failed to start %s Service" % svc)
            emit_err("Shutting down")
            for svc in svc_list:
                svc_off = ipaservices.service(svc)
                try:
                    svc_off.stop(capture_output=False)
                except:
                    pass
            try:
                dirsrv.stop(capture_output=False)
            except:
                pass
            raise IpactlError("Aborting ipactl")

def ipa_stop(options):
    dirsrv = ipaservices.knownservices.dirsrv
    try:
        svc_list = get_config_from_file()
    except Exception, e:
        # Issue reading the file ? Let's try to get data from LDAP as a
        # fallback
        try:
            dirsrv.start(capture_output=False)
            svc_list = get_config(dirsrv)
        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
                dirsrv.stop()
            finally:
                raise IpactlError()

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

    for svc in reversed(svc_list):
        svchandle = ipaservices.service(svc)
        try:
            print "Stopping %s Service" % svc
            svchandle.stop(capture_output=False)
        except:
            emit_err("Failed to stop %s Service" % svc)

    # remove file with list of started services
    try:
        os.unlink(ipaservices.SVC_LIST_FILE)
    except OSError:
        pass


def ipa_restart(options):
    dirsrv = ipaservices.knownservices.dirsrv
    new_svc_list = []
    try:
        new_svc_list = get_config(dirsrv)
    except Exception, e:
        emit_err("Failed to read data from Directory Service: " + str(e))
        emit_err("Shutting down")
        try:
            dirsrv.stop(capture_output=False)
        except:
            pass
        if isinstance(e, IpactlError):
            # do not display any other error message
            raise IpactlError(rval=e.rval)
        else:
            raise IpactlError()

    old_svc_list = []
    try:
        old_svc_list = get_config_from_file()
    except Exception, e:
        emit_err("Failed to get service list from file: " + str(e))
        # fallback to what's in LDAP
        old_svc_list = new_svc_list

    # match service to start/stop
    svc_list = []
    for s in new_svc_list:
        if s in old_svc_list:
            svc_list.append(s)

    #remove commons
    for s in svc_list:
        if s in old_svc_list:
            old_svc_list.remove(s)
    for s in svc_list:
        if s in new_svc_list:
            new_svc_list.remove(s)

    if len(old_svc_list) != 0:
        # we need to definitely stop some services
        for svc in reversed(old_svc_list):
            svchandle = ipaservices.service(svc)
            try:
                print "Stopping %s Service" % svc
                svchandle.stop(capture_output=False)
            except:
                emit_err("Failed to stop %s Service" % svc)

    try:
        print "Restarting Directory Service"
        dirsrv.restart(capture_output=get_capture_output('dirsrv', options.debug))
    except Exception, e:
        emit_err("Failed to restart Directory Service: " + str(e))
        emit_err("Shutting down")
        for svc in reversed(svc_list):
            svc_off = ipaservices.service(svc)
            try:
                svc_off.stop(capture_output=False)
            except:
                pass
        try:
            dirsrv.stop(capture_output=False)
        except:
            pass
        raise IpactlError("Aborting ipactl")

    if len(svc_list) != 0:
        # there are services to restart

        for svc in svc_list:
            svchandle = ipaservices.service(svc)
            try:
                print "Restarting %s Service" % svc
                svchandle.restart(capture_output=get_capture_output(svc, options.debug))
            except:
                emit_err("Failed to restart %s Service" % svc)
                emit_err("Shutting down")
                for svc in reversed(svc_list):
                    svc_off = ipaservices.service(svc)
                    try:
                        svc_off.stop(capture_output=False)
                    except:
                        pass
                try:
                    dirsrv.stop(capture_output=False)
                except:
                    pass
                raise IpactlError("Aborting ipactl")

    if len(new_svc_list) != 0:
        # we still need to start some services
        for svc in new_svc_list:
            svchandle = ipaservices.service(svc)
            try:
                print "Starting %s Service" % svc
                svchandle.start(capture_output=get_capture_output(svc, options.debug))
            except:
                emit_err("Failed to start %s Service" % svc)
                emit_err("Shutting down")
                for svc in reversed(svc_list):
                    svc_off = ipaservices.service(svc)
                    try:
                        svc_off.stop(capture_output=False)
                    except:
                        pass
                try:
                    dirsrv.stop(capture_output=False)
                except:
                    pass
                raise IpactlError("Aborting ipactl")

def ipa_status(options):

    try:
        svc_list = get_config_from_file()
    except IpactlError, e:
        if os.path.exists(ipaservices.get_svc_list_file()):
            raise e
        else:
            svc_list = []
    except Exception, e:
        raise IpactlError("Failed to get list of services to probe status: " + str(e))

    dirsrv = ipaservices.knownservices.dirsrv
    try:
        if dirsrv.is_running():
            print "Directory Service: RUNNING"
        else:
            print "Directory Service: STOPPED"
            if len(svc_list) == 0:
                print ("Directory Service must be running in order to " +
                      "obtain status of other services")
    except:
        raise IpactlError("Failed to get Directory Service status")

    if len(svc_list) == 0:
        return

    for svc in svc_list:
        svchandle = ipaservices.service(svc)
        try:
            if svchandle.is_running():
                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='ipactl', 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)


if __name__ == '__main__':
    installutils.run_script(main, operation_name='ipactl')
