import os
import logging
import netaddr
import Bcfg2.Server.Plugin

class AclFile(Bcfg2.Server.Plugin.XMLFileBacked):
    """ representation of ACL config.xml """

    # 'name' error without this tag
    __identifier__ = None

    def __init__(self, filename, core=None):
        # create config.xml if missing
        if not os.path.exists(filename):
            LOGGER.warning("Acl: %s missing. "
                           "Creating empty one for you." % filename)
            open(filename, "w").write("<IPs></IPs>")

        try:
            fam = core.fam
        except AttributeError:
            fam = None

        Bcfg2.Server.Plugin.XMLFileBacked.__init__(self, filename, fam=fam,
                                                   should_monitor=True)
        self.core = core
        self.cidr_ips = []
        self.ips = []
        self.logger = logging.getLogger(self.__class__.__name__)
    
    def Index(self):
        Bcfg2.Server.Plugin.XMLFileBacked.Index(self)
        for entry in self.xdata.xpath('//IPs'):
            [self.ips.append(i.get('name')) for i in entry.findall('IP')]
            [self.cidr_ips.append(i.get('name')) for i in entry.findall('CIDR')]
    
    def check_acl(self, ip):
        if ip in self.ips:
            return True
        for cidr_ip in self.cidr_ips:
            if netaddr.IPAddress(ip) in netaddr.IPNetwork(cidr_ip):
                return True
        return False

class Acl(Bcfg2.Server.Plugin.Plugin,
          Bcfg2.Server.Plugin.Connector):
    """ allow connections to bcfg-server based on IP address """

    def __init__(self, core, datastore):
        Bcfg2.Server.Plugin.Plugin.__init__(self, core, datastore)
        Bcfg2.Server.Plugin.Connector.__init__(self)
        self.config = AclFile(os.path.join(self.data, 'config.xml'), core=core)