"""
To use this lookup plugin, you need to pass ldap:
ssh -L 1636:172.16.10.1:636 172.16.10.1
"""

import ipaddress

from ansible.errors import AnsibleError, AnsibleParserError
from ansible.plugins.lookup import LookupBase
from ansible.utils.display import Display

try:
    import ldap
except ImportError:
    raise AnsibleError("You need to install python3-ldap")

display = Display()

def decode_object(object):
    return {attribute: [value.decode('utf-8') for value in object[attribute]] for attribute in object}

class LookupModule(LookupBase):

    def __init__(self, **kwargs):
        self.base = ldap.initialize('ldaps://localhost:1636/')
        self.base.set_option(ldap.OPT_X_TLS_REQUIRE_CERT, ldap.OPT_X_TLS_ALLOW)
        self.base.set_option(ldap.OPT_X_TLS_NEWCTX, 0)
        self.base_dn = 'dc=crans,dc=org'

    def query(self, base, scope, filter='(objectClass=*)', attr=None):
        """
        Make a LDAP query
        query('ldap', 'query', BASE, SCOPE[, FILTER[, ATTR]])
           BASE: base dn
           SCOPE: 'base', 'one' or 'sub'
           FILTER: ldap filter (optional)
           ATTR: list of attributes (optional)
        """
        scope = { 'base': ldap.SCOPE_BASE, 'one': ldap.SCOPE_ONELEVEL, 'sub': ldap.SCOPE_SUBTREE }[scope]
        query_id = self.base.search(f"{base}", scope, filter, attr)
        result = self.base.result(query_id)[1]
        result = { dn: decode_object(entry) for dn, entry in result }
        return result

    def ip(self, host, vlan):
        """
        Retrieve IP addresses of an interface of a device
        query('ldap', 'ip', HOST, VLAN)
        """
        if isinstance(vlan, int):
            network_query_id = self.base.search(f"ou=networks,{self.base_dn}", ldap.SCOPE_ONELEVEL, f"description={vlan}")
            network_result = self.base.result(network_query_id)
            vlan = network_result[1][0][1]['cn'][0].decode('utf-8')
        if vlan == 'srv':
            query_id = self.base.search(f"cn={host}.crans.org,cn={host},ou=hosts,{self.base_dn}", ldap.SCOPE_BASE)
        else:
            query_id = self.base.search(f"cn={host}.{vlan}.crans.org,cn={host},ou=hosts,{self.base_dn}", ldap.SCOPE_BASE)
        result = self.base.result(query_id)
        result = result[1][0][1]
        result = [res.decode('utf-8') for res in result['ipHostNumber']]
        return result

    def subnet_ipv4(self, subnet):
        """
        Retrive used IP addresses on a subnet
        query('ldap', 'subnet_ipv4', SUBNET)
        """
        network_query_id = self.base.search(f"cn={subnet},ou=networks,{self.base_dn}", ldap.SCOPE_BASE)
        network_result = self.base.result(network_query_id)
        network = network_result[1][0][1]
        network, hostmask = network['ipNetworkNumber'][0].decode('utf-8'), network['ipNetmaskNumber'][0].decode('utf-8')
        subnet = ipaddress.IPv4Network(f"{network}/{hostmask}")
        query_id = self.base.search(f"ou=hosts,{self.base_dn}", ldap.SCOPE_SUBTREE, "objectClass=ipHost")
        result = self.base.result(query_id)
        result = [ip.decode('utf-8') for dn, entry in result[1] for ip in entry['ipHostNumber'] if ipaddress.ip_address(ip.decode('utf-8')) in subnet]
        return result

    def run(self, terms, variables=None, **kwargs):
        if terms[0] == 'query':
            result = self.query(*terms[1:])
        elif terms[0] == 'ip':
            result = self.ip(*terms[1:])
        elif terms[0] == 'subnet_ipv4':
            result = self.subnet_ipv4(*terms[1:])
        elif terms[0] == 'group':
            query_id = self.base.search(f"ou=group,{self.base_dn}", ldap.SCOPE_SUBTREE, "objectClass=posixGroup")
            result = self.base.result(query_id)
            result = result[1]
        # query interface attribute
        # query('ldap', 'hosts', HOST, VLAN, ATTR)
        #   HOST: device name
        #   VLAN: vlan name
        #   ATTR: attribute
        elif terms[0] == 'hosts':
            host = terms[1]
            vlan = terms[2]
            attr = terms[3]
            if isinstance(vlan, int):
                network_query_id = self.base.search(f"ou=networks,{self.base_dn}", ldap.SCOPE_ONELEVEL, f"description={vlan}")
                network_result = self.base.result(network_query_id)
                vlan = network_result[1][0][1]['cn'][0].decode('utf-8')
            if vlan == 'srv':
                query_id = self.base.search(f"cn={host}.crans.org,cn={host},ou=hosts,{self.base_dn}", ldap.SCOPE_BASE)
            else:
                query_id = self.base.search(f"cn={host}.{vlan}.crans.org,cn={host},ou=hosts,{self.base_dn}", ldap.SCOPE_BASE)
            result = self.base.result(query_id)
            result = result[1][0][1]
            result = [res.decode('utf-8') for res in result[attr]]
        elif terms[0] == 'network':
            network = terms[1]
            query_id = self.base.search(f"cn={network},ou=networks,{self.base_dn}", ldap.SCOPE_BASE, "objectClass=ipNetwork")
            result = self.base.result(query_id)
            result = result[1][0][1]
            return str(ipaddress.ip_network('{}/{}'.format(result['ipNetworkNumber'][0].decode('utf-8'), result['ipNetmaskNumber'][0].decode('utf-8'))))
        elif terms[0] == 'zones':
            query_id = self.base.search(f"ou=networks,{self.base_dn}", ldap.SCOPE_ONELEVEL, "objectClass=ipNetwork")
            result = self.base.result(query_id)
            res = []
            for _, network in result[1]:
                network = network['cn'][0].decode('utf-8')
                if network == 'srv':
                    res.append('crans.org')
                else:
                    res.append(f"{network}.crans.org")
            result = res
        elif terms[0] == 'vlanid':
            network = terms[1]
            query_id = self.base.search(f"cn={network},ou=networks,{self.base_dn}", ldap.SCOPE_BASE, "objectClass=ipNetwork")
            result = self.base.result(query_id)
            result = result[1][0][1]
            return int(result['description'][0])
        elif terms[0] == 'role':
            role = terms[1]
            query_id = self.base.search(f"ou=hosts,{self.base_dn}", ldap.SCOPE_ONELEVEL, f"description={role}")
            result = self.base.result(query_id)
            result = [cn.decode('utf-8') for res in result[1] for cn in res[1]['cn']]
        return result