#!/usr/bin/env python

'''Bcfg2 Client'''
__revision__ = '$Revision$'

import logging
import os
import signal
import socket
import sys
import tempfile
import time
import xmlrpclib
import fcntl
import Bcfg2.Options
import Bcfg2.Client.XML
import Bcfg2.Client.Frame
import Bcfg2.Client.Tools
import Bcfg2.Daemon

import Bcfg2.Proxy
import Bcfg2.Logger

logger = logging.getLogger('bcfg2')

def cb_sigint_handler(signum, frame):
    '''Exit upon CTRL-C'''
    os._exit(1)

DECISION_LIST = Bcfg2.Options.Option('Decision List', default=False,
                                     cmd="--decision-list", odesc='<file>',
                                     long_arg=True)
LOCKFILE = "/var/lock/bcfg2.run"


class Client:
    ''' The main bcfg2 client class '''

    def __init__(self):
        self.toolset = None
        self.config = None

        optinfo = {
            # 'optname': (('-a', argdesc, optdesc),
            #                  env, cfpath, default, boolean)),
            'verbose': Bcfg2.Options.VERBOSE,
            'extra': Bcfg2.Options.CLIENT_EXTRA_DISPLAY,
            'quick': Bcfg2.Options.CLIENT_QUICK,
            'debug': Bcfg2.Options.DEBUG,
            'drivers': Bcfg2.Options.CLIENT_DRIVERS,
            'fingerprint': Bcfg2.Options.SERVER_FINGERPRINT,
            'dryrun': Bcfg2.Options.CLIENT_DRYRUN,
            'paranoid': Bcfg2.Options.CLIENT_PARANOID,
            'bundle': Bcfg2.Options.CLIENT_BUNDLE,
            'file': Bcfg2.Options.CLIENT_FILE,
            'interactive': Bcfg2.Options.INTERACTIVE,
            'cache': Bcfg2.Options.CLIENT_CACHE,
            'profile': Bcfg2.Options.CLIENT_PROFILE,
            'remove': Bcfg2.Options.CLIENT_REMOVE,
            'help': Bcfg2.Options.HELP,
            'setup': Bcfg2.Options.CFILE,
            'server': Bcfg2.Options.SERVER_LOCATION, 
            'user': Bcfg2.Options.CLIENT_USER,
            'password': Bcfg2.Options.SERVER_PASSWORD,
            'retries': Bcfg2.Options.CLIENT_RETRIES,
            'kevlar': Bcfg2.Options.CLIENT_KEVLAR,
            'agent': Bcfg2.Options.CLIENT_AGENT,
            'agent-port': Bcfg2.Options.CLIENT_PORT,
            'agent-background': Bcfg2.Options.CLIENT_BACKGROUND,
            'key': Bcfg2.Options.SERVER_KEY,
            'decision-list': DECISION_LIST,
            'encoding': Bcfg2.Options.ENCODING,
            'omit-lock-check': Bcfg2.Options.OMIT_LOCK_CHECK,
            'filelog': Bcfg2.Options.LOGGING_FILE_PATH,
            'decision': Bcfg2.Options.CLIENT_DLIST,
            'servicemode': Bcfg2.Options.CLIENT_SERVICE_MODE,
            'key'             : Bcfg2.Options.CLIENT_KEY,
            'certificate'     : Bcfg2.Options.CLIENT_CERT,
            'ca'              : Bcfg2.Options.CLIENT_CA,
            }

        self.setup = Bcfg2.Options.OptionParser(optinfo)
        self.setup.parse(sys.argv[1:])

        if self.setup['args']:
            print("Bcfg2 takes no arguments, only options")
            print(self.setup.buildHelpMessage())
            raise SystemExit(1)
        level = 30
        if self.setup['verbose']:
            level = 20
        if self.setup['debug']:
            level = 0
        Bcfg2.Logger.setup_logging('bcfg2', to_syslog=False, level=level, to_file=self.setup['filelog'])
        self.logger = logging.getLogger('bcfg2')
        self.logger.debug(self.setup)
        if 'drivers' in self.setup and self.setup['drivers'] == 'help':
            self.logger.info("The following drivers are available:")
            self.logger.info(Bcfg2.Client.Tools.drivers)
            raise SystemExit(0)
        if self.setup['remove'] and 'services' in self.setup['remove']:
            self.logger.error("Service removal is nonsensical, disable services to get former behavior")
        if self.setup['remove'] not in [False, 'all', 'services', 'packages']:
            self.logger.error("Got unknown argument %s for -r" % (self.setup['remove']))
        if (self.setup["file"] != False) and (self.setup["cache"] != False):
            print("cannot use -f and -c together")
            raise SystemExit(1)
        if (self.setup["agent"] != False) and (self.setup["interactive"] != False):
            print("cannot use -A and -I together")
            raise SystemExit(1)
        if (self.setup["agent"] and not self.setup["fingerprint"]):
            print("Agent mode requires specification of x509 fingerprint")
            raise SystemExit(1)
        if (self.setup["agent"] and not self.setup["key"]):
            print("Agent mode requires specification of ssl cert + key file")
            raise SystemExit(1)

    def run_probe(self, probe):
        '''Execute probe'''
        name = probe.get('name')
        self.logger.info("Running probe %s" % name)
        ret = Bcfg2.Client.XML.Element("probe-data", name=name, source=probe.get('source'))
        try:
            scripthandle, scriptname = tempfile.mkstemp()
            script = open(scriptname, 'w+')
            try:
                script.write("#!%s\n" %
                             (probe.attrib.get('interpreter', '/bin/sh')))
                script.write(probe.text)
                script.close()
                os.close(scripthandle)
                os.chmod(script.name, 0755)
                ret.text = os.popen(script.name).read().strip()
                self.logger.info("Probe %s has result:\n%s" % (name, ret.text))
            finally:
                os.unlink(script.name)
        except:
            self.logger.error("Failed to execute probe: %s" % (name), exc_info=1)
            raise SystemExit(1)
        return ret

    def fatal_error(self, message):
        '''Signal a fatal error'''
        self.logger.error("Fatal error: %s" % (message))
        if not self.setup["agent"]:
            raise SystemExit(1)
        else:
            self.logger.error("Continuing...")
        
    def run(self):
        ''' Perform client execution phase '''
        times = {}

        # begin configuration
        times['start'] = time.time()

        if self.setup['file']:
            # read config from file
            try:
                self.logger.debug("reading cached configuration from %s" %
                                  (self.setup['file']))
                configfile = open(self.setup['file'], 'r')
                rawconfig = configfile.read()
                configfile.close()
            except IOError:
                self.fatal_error("failed to read cached configuration from: %s"
                                 % (self.setup['file']))
                return(1)
        else:
            # retrieve config from server
            proxy = Bcfg2.Proxy.ComponentProxy(self.setup['server'],
                                               self.setup['user'],
                                               self.setup['password'],
                                               key = self.setup['key'],
                                               cert = self.setup['certificate'],
                                               ca = self.setup['ca'])

            if self.setup['profile']:
                try:
                    proxy.AssertProfile(self.setup['profile'])
                except xmlrpclib.Fault:
                    self.fatal_error("Failed to set client profile")
                    return(1)

            try:
                probe_data = proxy.GetProbes()
            except xmlrpclib.Fault, flt:
                self.logger.error("Failed to download probes from bcfg2")
                self.logger.error(flt.faultString)
                raise SystemExit(1)

            times['probe_download'] = time.time()

            try:
                probes = Bcfg2.Client.XML.XML(probe_data)
            except Bcfg2.Client.XML.ParseError, syntax_error:
                self.fatal_error(
                    "server returned invalid probe requests: %s" %
                    (syntax_error))
                return(1)

            # execute probes
            try:
                probedata = Bcfg2.Client.XML.Element("ProbeData")
                [probedata.append(self.run_probe(probe))
                 for probe in probes.findall(".//probe")]
            except:
                self.logger.error("Failed to Execute probes")
                raise SystemExit(1)

            if len(probes.findall(".//probe")) > 0:
                try:
                    # upload probe responses
                    proxy.RecvProbeData(Bcfg2.Client.XML.tostring(probedata, encoding='UTF-8', xml_declaration=True))
                except:
                    self.logger.error("Failed to upload probe data", exc_info=1)
                    raise SystemExit(1)

            times['probe_upload'] = time.time()

            if self.setup['decision'] in ['whitelist', 'blacklist']:
                try:
                    self.setup['decision_list'] = proxy.GetDecisionList( \
                        self.setup['decision'])
                    self.logger.info("Got Decision List from server:")
                    self.logger.info(self.setup['decision_list'])
                except xmlrpclib.Fault, f:
                    if f.faultCode == 1:
                        print("GetDecisionList method not supported by server")
                    else:
                        self.logger.error("Failed to de", exc_info=1)
                    raise SystemExit(1)

            try:
                rawconfig = proxy.GetConfig()
            except xmlrpclib.Fault:
                self.logger.error("Failed to download configuration from bcfg2")
                raise SystemExit(2)

            times['config_download'] = time.time()

        if self.setup['cache']:
            try:
                open(self.setup['cache'], 'w').write(rawconfig)
                os.chmod(self.setup['cache'], 33152)
            except IOError:
                self.logger.warning("failed to write config cache file %s" %
                                    (self.setup['cache']))
            times['caching'] = time.time()

        try:
            self.config = Bcfg2.Client.XML.XML(rawconfig)
        except Bcfg2.Client.XML.ParseError, syntax_error:
            self.fatal_error("the configuration could not be parsed: %s" %
                             (syntax_error))
            return(1)            

        times['config_parse'] = time.time()

        if self.config.tag == 'error':
            self.fatal_error("server error: %s" % (self.config.text))
            return(1)

        self.tools = Bcfg2.Client.Frame.Frame(self.config,
                                              self.setup,
                                              times, self.setup['drivers'],
                                              self.setup['dryrun'])

        if not self.setup['omit-lock-check']:
            #check lock here
            try:
                lockfile = open(LOCKFILE, 'w')
                try:
                    fcntl.lockf(lockfile.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
                except IOError:
                    #otherwise exit and give a warning to the user
                    self.fatal_error("An other instance of bcfg2 is running. If you what to bypass the check, run with %s option" %
                                     (Bcfg2.Options.OMIT_LOCK_CHECK.cmd))
            except:
                lockfile = None
                self.logger.error("Failed to open lockfile")
        # execute the said configuration
        self.tools.Execute()

        if not self.setup['omit-lock-check']:
            #unlock here
            if lockfile:
                fcntl.lockf(lockfile.fileno(), fcntl.LOCK_UN)
                os.remove(LOCKFILE)
        
        if not self.setup['file']:
            # upload statistics
            feedback = self.tools.GenerateStats()

            try:
                proxy.RecvStats(Bcfg2.Client.XML.tostring(feedback, encoding='UTF-8', xml_declaration=True))
            except xmlrpclib.Fault:
                self.logger.error("Failed to upload configuration statistics")
                raise SystemExit(2)

if __name__ == '__main__':
    signal.signal(signal.SIGINT, cb_sigint_handler)
    client = Client()
    spid = os.getpid()
    if client.setup["agent"]:
        agent = Agent(client)
        if client.setup["agent-background"]:
            Bcfg2.Daemon.daemonize(client.setup["agent-background"])
        while not agent.shut:
            try:
                agent.serve_forever()
            except:
                agent.logger.error('Error in service loop')
                agent.logger.error('Continuing')
        if os.getpid() == spid:
            print("Shutting down")
    else:
        client.run()