#!/usr/bin/env python
# Python helper tool to add IPtables rule using the iptc library. This must
# of course run as root for iptc to work.

from sys import exit
from argparse import ArgumentParser, FileType, ArgumentTypeError
from pprint import pprint as pp
from configparser import RawConfigParser
from datetime import datetime, timedelta

import errors
from storage import StoragePostgres
from client import Client


# Custom defined argparse types for dates
def valid_date_type(arg_date_str):
    """custom argparse *date* type for user dates values given from the command line"""
    try:
        return datetime.strptime(arg_date_str, "%Y-%m-%d")
    except ValueError:
        msg = "Given Date ({0}) not valid! Expected format, YYYY-MM-DD!".format(arg_date_str)
        raise ArgumentTypeError(msg)


def valid_datetime_type(arg_datetime_str):
    """custom argparse type for user datetime values given from the command line"""
    try:
        return datetime.strptime(arg_datetime_str, "%Y-%m-%d %H:%M")
    except ValueError:
        msg = "Given Datetime ({0}) not valid! Expected format, 'YYYY-MM-DD HH:mm'!".format(arg_datetime_str)
        raise ArgumentTypeError(msg) 


parser = ArgumentParser((
    'Handle clients in the captive portal. Default mode of operation is to'
    ' create new clients and enable them. Other mode is to --disable the '
    'client. And last mode is to --delete the client completely.'
))

parser.add_argument(
    '--expires',
    type=valid_datetime_type,
    default=datetime.now() + timedelta(days=1),
    help='Expiry date in format "YYYY-MM-DD HH:mm"'
)

parser.add_argument(
    '--disable',
    default=False,
    action='store_true',
    help='Disable the client in the DB and delete from firewall'
)

parser.add_argument(
    '--delete',
    default=False,
    action='store_true',
    help='Delete the client from DB and firewall'
)

parser.add_argument(
    '--protocol',
    required=True,
    choices=['tcp', 'udp'],
    help='Protocol for client'
)

parser.add_argument(
    '--config',
    type=FileType('r'),
    required=True,
    help='Configuration file'
)

parser.add_argument(
    'src_ip',
    help='Client source IP to add'
)

args = parser.parse_args()

config = RawConfigParser()
config.readfp(args.config)

sr = StoragePostgres(config=config)
try:
    client = Client(
        storage=sr,
        ip_address=args.src_ip,
        protocol=args.protocol,
        chain=config.get('iptables', 'chain')
    )
except errors.StorageNotFound:
    print('Client not found')
    exit(1)

if args.disable:
    enabled = False
else:
    enabled = True

if args.delete:
    # This both deletes the iptables rule AND the client entry from DB.
    client.delete()
else:
    if args.expires:
        client.expires = args.expires
    client.enabled = enabled
    client.commit()