#!/usr/bin/python
# vim: set fileencoding=utf-8 :

import os
import sys
import datetime
import argparse
import logging
import configobj

# parse command line options
parser = argparse.ArgumentParser(
        description='Hosts maintainer for py-i2phosts.',
        epilog='Report bugs to https://github.com/i2phosts/py-i2phosts/issues')
parser.add_argument('-d', '--debug', action='store_true',
        help='write debug messages to stdout')
parser.add_argument('-c', '--config', default='/etc/py-i2phosts/maintainer.conf', dest='config_file',
        help='config file to use')
args = parser.parse_args()

# read config
spec = '''
    log_file = string(default='/var/log/py-i2phosts/maintainer.log')
    log_level = option('debug', 'info', 'warning', 'error', 'critical', default='info')
    external_inactive_max = integer(default=365)
    internal_inactive_max = integer(default=14)
    external_expires = integer(default=30)
    internal_expires = integer(default=30)
    activate_min_delay = integer(default=3)
    keep_expired = integer(default=730)
    '''
spec = spec.split('\n')
config = configobj.ConfigObj(args.config_file, configspec=spec)
if 'include' in config:
    config_included = configobj.ConfigObj(config['include'])
    config.merge(config_included)

# django setup
DJANGO_SETTINGS_MODULE = 'pyi2phosts.settings'
if 'DJANGO_PROJECT_PATH' in config:
    DJANGO_PROJECT_PATH = config['DJANGO_PROJECT_PATH']
else:
    DJANGO_PROJECT_PATH = os.path.dirname(sys.argv[0]) + '/..'
sys.path.insert(1, DJANGO_PROJECT_PATH)
os.environ['DJANGO_SETTINGS_MODULE'] = DJANGO_SETTINGS_MODULE
import django
django.setup()
from pyi2phosts.postkey.models import i2phost
from pyi2phosts.lib.utils import get_logger
from pyi2phosts.lib.utils import validate_config

# validate config
validate_config(config)

# configure logger
if args.debug == True:
    log_level = 'debug'
    log_file = None
else:
    log_level = config['log_level']
    log_file = config['log_file']
log = get_logger(filename=log_file, log_level=log_level)

all_hosts = i2phost.objects.all()
log.info('starting maintenance')
for host in all_hosts:
    # how long host was added
    dl = datetime.datetime.utcnow() - host.date_added
    if host.last_seen == None:
        # delete external hosts which we never seen after X days of inactivity
        if host.external == True:
            if dl > datetime.timedelta(days=config['external_inactive_max']):
                log.info('deleting %s, reason: external host, never seen for %s days',
                        host.name, config['external_inactive_max'])
                host.delete()
                continue
        # delete hosts added by us and never seen after X days of inactivity
        else:
            if dl > datetime.timedelta(days=config['internal_inactive_max']):
                log.info('deleting %s, reason: internal host, never seen for %s days',
                        host.name, config['internal_inactive_max'])
                host.delete()
                continue
    else:
        # configure registration period for hosts
        if host.external == True:
            timedelta = datetime.timedelta(days=config['external_expires'])
        else:
            timedelta = datetime.timedelta(days=config['internal_expires'])
        # get current host expiration date from database
        if host.expires == None:
            # workaround for situation when we updating expires first time
            expires_current = datetime.datetime.utcnow().date()
            host.expires = expires_current
        else:
            expires_current = host.expires
        # calculate new expiration date
        expires_new = host.last_seen + timedelta
        expires_new = expires_new.date()
        # update expiration date only if changed
        if expires_new > expires_current:
            log.debug('updating expires for %s', host.name)
            host.expires = expires_new
        # deactivate if expired
        min_dl = datetime.timedelta(days=config['activate_min_delay'])
        if host.expires < datetime.datetime.utcnow().date():
            if host.activated == True:
                log.info('deactivating %s, reason: expired', host.name)
                host.activated = False
        # if not expired and added more than X days ago and approved then activate
        elif dl > min_dl and host.activated == False and host.approved == True:
            log.info('activating %s, reason: host up and added more than %s days ago',
                    host.name, config['activate_min_delay'])
            host.activated = True
        # if expired X days ago then delete
        dl_e = datetime.datetime.utcnow().date() - host.expires
        if dl_e > datetime.timedelta(days=config['keep_expired']):
            log.info('deleting %s, reason: expired %s days ago',
                    host.name, config['keep_expired'])
            host.delete()
            continue
        host.save()