#!/usr/bin/env python
# Contributed by gogo

'''TODO'''
__revision__ = '$Revision: 221 $'

import logging, lxml.etree, Bcfg2.Logging, Bcfg2.Server.Core, Bcfg2.Server.Metadata, Bcfg2.Server.Plugin
import sys,os,time,errno
from optparse import OptionParser

def buildConfiguration(core, client):
  '''Build client configuration.'''

  return core.BuildConfiguration(client)

def write_siggi_entry(user, group, permission, path):
  '''Write an entry to the configfiles.siggi file which is needed by siggi.'''
  f = open(outputdir + '/configfiles.siggi', 'a')
  f.write("%s,%s,%s,%s\n" % (user, group, permission, path))
  f.close()
  logger.info("Wrote siggi entry." )

class ConfigFileNotBuild(Exception):
  def __init__(self, value):
    self.value = value
  def __str__(self):
    return repr(self.value)


def handleConfigFileEntry(cfg):
  '''Store file content of an <ConfigFile name='/path/to/file' ...>...</ConfigFile> entry
  in the appropriate directory under the output directory.'''
  name       = cfg.get('name')
  permission = cfg.get('perms').rjust(4,'0')
  user       = cfg.get('owner')
  group      = cfg.get('group')

  logger.info("\nHandling ConfigFile entry %s >>>" % name)

  # directory creation
  logger.info("Creating directory %s" % ( os.path.dirname(outputdir + name)) )
  try:
    os.makedirs(os.path.dirname(outputdir + name))
  except OSError,err:
    if err.errno != errno.EEXIST:
      raise
  except:
    logger.error("Fatal error during directory creation!")
    raise

  # write config file
  f = open(outputdir + name, "w" )
  try:
    f.write(cfg.text)
  except: # plugin throw an exception and therefore there is no content => None
    raise ConfigFileNotBuild(name)
  f.close()

  # write siggi entry
  try:
    write_siggi_entry(user, group, permission, name)
  except:
    logger.error("Writing entry to configfiles.siggi failed!")
    raise

  logger.info("<<<")

if __name__ == '__main__':
  Bcfg2.Logging.setup_logging('export-config-AMS', to_syslog=False)
  logger = logging.getLogger('export-config-AMS')

  # parse command line options, arguments
  parser = OptionParser(usage = "%prog [options] client outputdir", version = __revision__)
  parser.add_option("-c", "--config-file", action="store", dest="configfile", 
      help="Use given bcfg2.conf file, default: /etc/bcfg2.conf")

  parser.add_option("-f", "--fam-steps", action="store", dest="famsteps",
      type = "int", help="How many times to handle fam events, default: 10")

  parser.set_defaults(famsteps = 10, configfile="/etc/bcfg2.conf")

  (options, args) = parser.parse_args()

  # ensure client hostname is given
  if len(args) != 2:
    parser.error("incorrect number of arguments.")

  client = args[0]
  outputdir = args[1]

  # stop if output directory exists
  if os.path.exists(outputdir):
    logger.error("Output directory already exists, won't override!")
    raise SystemExit, 1

  logger.info("Generating configuration for %s" % client)

  # load Bcfg2 Core
  try:
    logger.debug("Trying to load core...")
    bcore = Bcfg2.Server.Core.Core({}, options.configfile)
  except Bcfg2.Server.Core.CoreInitError, msg:
    logger.error("Core load failed because %s" % msg)
    raise SystemExit, 1
  else:
    logger.debug("Core loaded.")

  # FAM service handling
  for i in range(options.famsteps):
    logger.info("FAM service handling: %s to go..." % str(options.famsteps - i) )
    bcore.fam.Service()
    time.sleep(0.5)

  # get configuration for client
  try:
    client_config = buildConfiguration( bcore, client)
  except:
    logger.error("Building client configuration failed. Exiting...")
    raise SystemExit, 1

  # client could be without a group, not listed in client.xml ...
  if client_config.tag == 'error':
    logger.error("Building client configuration failed. Exiting...")
    raise SystemExit, 1

  # handle <ConfigFile> entries
  for configfile in [cfile for cfile in client_config.findall(".//ConfigFile")]:
    try:
      handleConfigFileEntry(configfile)
    except ConfigFileNotBuild, e:
      logger.error("Error: Plugin failed to generate file content for ConfigFile %s !" % e)
      raise SystemExit, 1
    except:
      raise SystemExit, 1