import os
import re

from util import hook


@hook.sieve
def sieve_suite(bot, input, func, args):
    events = args.get('events', ['PRIVMSG'])

    if input.command not in events and events != '*':
        return None

    if input.nick.lower()[-3:] == 'bot' and args.get('ignorebots', True):
        return None

    regex = args.get('re')
    if not regex:
        hook = args.get('hook', r'(.*)')

        if args.get('prefix', True):
            if input.chan == input.nick: # private message, prefix not required
                prefix = r'^(?:[.!]?|'
            else:
                prefix = r'^(?:[.!]|'
            hook = prefix + input.conn.nick + r'[:,]*\s)' + hook

        regex = re.compile(hook, flags=re.I)
        args['re'] = regex

    input.re = regex.match(input.msg)
    if input.re is None:
        return None

    acl = bot.config.get('acls', {}).get(func.__name__)
    if acl:
        if 'deny-except' in acl:
            allowed_channels = map(str.lower, acl['deny-except'])
            if input.chan.lower() not in allowed_channels:
                return None
        if 'allow-except' in acl:
            denied_channels = map(str.lower, acl['allow-except'])
            if input.chan.lower() in denied_channels:
                return None

    input.inp_unstripped = ' '.join(input.re.groups())
    input.inp = input.inp_unstripped.strip()

    return input