# Authors: Karl MacMillan <kmacmillan@mentalrootkit.com>
#
# Copyright (C) 2007  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; version 2 only
#
# 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, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#

import logging, sys
import os
import tempfile
from ipapython import sysrestore
from ipapython import ipautil
from ipalib import uuid, errors
import ldap
from ipaserver import ipaldap
import base64


def stop(service_name, instance_name=""):
    ipautil.run(["/sbin/service", service_name, "stop", instance_name])

def start(service_name, instance_name=""):
    ipautil.run(["/sbin/service", service_name, "start", instance_name])

def restart(service_name, instance_name=""):
    ipautil.run(["/sbin/service", service_name, "restart", instance_name])

def is_running(service_name, instance_name=""):
    ret = True
    try:
        ipautil.run(["/sbin/service", service_name, "status", instance_name])
    except ipautil.CalledProcessError:
        ret = False
    return ret

def chkconfig_on(service_name):
    ipautil.run(["/sbin/chkconfig", service_name, "on"])

def chkconfig_off(service_name):
    ipautil.run(["/sbin/chkconfig", service_name, "off"])

def chkconfig_add(service_name):
    ipautil.run(["/sbin/chkconfig", "--add", service_name])

def chkconfig_del(service_name):
    ipautil.run(["/sbin/chkconfig", "--del", service_name])

def is_enabled(service_name):
    (stdout, stderr, returncode) = ipautil.run(["/sbin/chkconfig", "--list", service_name])

    runlevels = {}
    for runlevel in range(0, 7):
        runlevels[runlevel] = False

    for line in stdout.split("\n"):
        parts = line.split()
        if parts[0] == service_name:
            for s in parts[1:]:
                (runlevel, status) = s.split(":")[0:2]
                try:
                    runlevels[int(runlevel)] = status == "on"
                except ValueError:
                    pass
            break

    return (runlevels[3] and runlevels[4] and runlevels[5])

def print_msg(message, output_fd=sys.stdout):
    logging.debug(message)
    output_fd.write(message)
    output_fd.write("\n")


class Service:
    def __init__(self, service_name, sstore=None, dm_password=None):
        self.service_name = service_name
        self.steps = []
        self.output_fd = sys.stdout
        self.dm_password = dm_password

        if sstore:
            self.sstore = sstore
        else:
            self.sstore = sysrestore.StateFile('/var/lib/ipa/sysrestore')

    def _ldap_mod(self, ldif, sub_dict = None):
        assert self.dm_password is not None

        fd = None
        path = ipautil.SHARE_DIR + ldif

        if sub_dict is not None:
            sub_dict['UUID'] = str(uuid.uuid1())
            txt = ipautil.template_file(path, sub_dict)
            fd = ipautil.write_tmp_file(txt)
            path = fd.name

        [pw_fd, pw_name] = tempfile.mkstemp()
        os.write(pw_fd, self.dm_password)
        os.close(pw_fd)

        args = ["/usr/bin/ldapmodify", "-h", "127.0.0.1", "-xv",
                "-D", "cn=Directory Manager", "-y", pw_name, "-f", path]

        try:
            try:
                ipautil.run(args)
            except ipautil.CalledProcessError, e:
                logging.critical("Failed to load %s: %s" % (ldif, str(e)))
        finally:
            os.remove(pw_name)

        if fd is not None:
            fd.close()

    def move_service(self, principal):
        """
        Used to move a principal entry created by kadmin.local from
        cn=kerberos to cn=services
        """
        dn = "krbprincipalname=%s,cn=%s,cn=kerberos,%s" % (principal, self.realm, self.suffix)
        try:
            conn = ipaldap.IPAdmin("127.0.0.1")
            conn.simple_bind_s("cn=directory manager", self.dm_password)
        except Exception, e:
            logging.critical("Could not connect to the Directory Server on %s: %s" % (self.fqdn, str(e)))
            raise e
        try:
            entry = conn.getEntry(dn, ldap.SCOPE_BASE)
        except errors.NotFound:
            # There is no service in the wrong location, nothing to do.
            # This can happen when installing a replica
            conn.unbind()
            return
        newdn = "krbprincipalname=%s,cn=services,cn=accounts,%s" % (principal, self.suffix)
        hostdn = "fqdn=%s,cn=computers,cn=accounts,%s" % (self.fqdn, self.suffix)
        conn.deleteEntry(dn)
        entry.dn = newdn
        classes = entry.getValues("objectclass")
        classes = classes + ["ipaobject", "ipaservice", "pkiuser"]
        entry.setValues("objectclass", list(set(classes)))
        entry.setValue("ipauniqueid", str(uuid.uuid1()))
        entry.setValue("managedby", hostdn)
        conn.addEntry(entry)
        conn.unbind()
        return newdn

    def add_cert_to_service(self):
        """
        Add a certificate to a service

        This should be passed in DER format but we'll be nice and convert
        a base64-encoded cert if needed (like when we add certs that come
        from PKCS#12 files.)
        """
        try:
            s = self.dercert.find('-----BEGIN CERTIFICATE-----')
            if s > -1:
                e = self.dercert.find('-----END CERTIFICATE-----')
                s = s + 27
                self.dercert = self.dercert[s:e]
                self.dercert = base64.b64decode(self.dercert)
        except Exception:
            pass
        dn = "krbprincipalname=%s,cn=services,cn=accounts,%s" % (self.principal, self.suffix)
        try:
            conn = ipaldap.IPAdmin("127.0.0.1")
            conn.simple_bind_s("cn=directory manager", self.dm_password)
        except Exception, e:
            logging.critical("Could not connect to the Directory Server on %s: %s" % (self.fqdn, str(e)))
            raise e
        mod = [(ldap.MOD_ADD, 'userCertificate', self.dercert)]
        try:
            conn.modify_s(dn, mod)
        except Exception, e:
            logging.critical("Could not add certificate to service %s entry: %s" % (self.principal, str(e)))
        conn.unbind()

    def is_configured(self):
        return self.sstore.has_state(self.service_name)

    def set_output(self, fd):
        self.output_fd = fd

    def stop(self, instance_name=""):
        stop(self.service_name, instance_name)

    def start(self, instance_name=""):
        start(self.service_name, instance_name)

    def restart(self, instance_name=""):
        restart(self.service_name, instance_name)

    def is_running(self):
        return is_running(self.service_name)

    def chkconfig_add(self):
        chkconfig_add(self.service_name)

    def chkconfig_del(self):
        chkconfig_del(self.service_name)

    def chkconfig_on(self):
        chkconfig_on(self.service_name)

    def chkconfig_off(self):
        chkconfig_off(self.service_name)

    def is_enabled(self):
        return is_enabled(self.service_name)

    def backup_state(self, key, value):
        self.sstore.backup_state(self.service_name, key, value)

    def restore_state(self, key):
        return self.sstore.restore_state(self.service_name, key)

    def print_msg(self, message):
        print_msg(message, self.output_fd)

    def step(self, message, method):
        self.steps.append((message, method))

    def start_creation(self, message):
        self.print_msg(message)

        step = 0
        for (message, method) in self.steps:
            self.print_msg("  [%d/%d]: %s" % (step+1, len(self.steps), message))
            method()
            step += 1

        self.print_msg("done configuring %s." % self.service_name)

        self.steps = []

class SimpleServiceInstance(Service):
    def create_instance(self):
        self.step("starting %s " % self.service_name, self.__start)
        self.step("configuring %s to start on boot" % self.service_name, self.__enable)
        self.start_creation("Configuring %s" % self.service_name)

    def __start(self):
        self.backup_state("running", self.is_running())
        self.restart()

    def __enable(self):
        self.chkconfig_add()
        self.backup_state("enabled", self.is_enabled())
        self.chkconfig_on()

    def uninstall(self):
        if self.is_configured():
            self.print_msg("Unconfiguring %s" % self.service_name)

        running = self.restore_state("running")
        enabled = not self.restore_state("enabled")

        if not running is None and not running:
            self.stop()
        if not enabled is None and not enabled:
            self.chkconfig_off()
            self.chkconfig_del()