defaults = {
    'apt': {
        'packages': {
            'isc-dhcp-server': {},
        },
    },
    'bash_aliases': {
        'leases': 'sudo dhcp-lease-list | tail -n +4 | sort -k 2,2',
    },
}


@metadata_reactor.provides(
    'dhcpd/fixed_allocations',
)
def get_static_allocations(metadata):
    allocations = {}
    for rnode in repo.nodes:
        if rnode.metadata.get('location', '') != metadata.get('location', ''):
            continue

        for iface_name, iface_config in rnode.metadata.get('interfaces', {}).items():
            if iface_config.get('dhcp', False):
                try:
                    allocations[f'{rnode.name}_{iface_name}'] = {
                        'ipv4': sorted(iface_config['ips'])[0],
                        'mac': iface_config['mac'],
                    }
                except KeyError:
                    pass

    return {
        'dhcpd': {
            'fixed_allocations': allocations,
        }
    }


@metadata_reactor.provides(
    'dhcpd/listen_interfaces',
)
def get_listen_interfaces(metadata):
    listen_interfaces = []
    for _, subnet in node.metadata.get('dhcpd/subnets', {}).items():
        listen_interfaces.append(subnet['interface'])

    return {
        'dhcpd': {
            'listen_interfaces': ' '.join(sorted(listen_interfaces)),
        }
    }


@metadata_reactor.provides(
    'iptables/bundle_rules/dhcpd',
)
def iptables(metadata):
    rules = set()
    for subnet in node.metadata.get('dhcpd/subnets', {}).values():
        rules.add('iptables -A INPUT -i {} -p udp --dport 67:68 -j ACCEPT'.format(subnet['interface']))

    return {
        'iptables': {
            'bundle_rules': {
                # can't use port_rules here. We're generating interface based rules here.
                'dhcpd': sorted(list(rules)),
            },
        }
    }