## python module definition

import re
debugModule = True

def qnameListToStr( qname_list ):
    qname_list_decode = list()
    for l in qname_list:
        qname_list_decode.append( l.decode('utf-8') )
    return ".".join( qname_list_decode )

def init_standard(id, env):
    log_info("aws-hostnames: init called, module id is %d port: %d script: %s verbosity: %s" % (id, env.cfg.port, env.cfg.python_script, env.cfg.verbosity))

    # Build pattern for checking, pattern matches everything like
    # ip-[0-9]-[0-9]-[0-9]-[0-9].domain.name
    global pattern
    pattern = re.compile("^ip-([0-9]+)-([0-9]+)-([0-9]+)-([0-9]+)\.")

    return True

# Module
def init(id, cfg):
    return True

def deinit(id):
    log_info("aws-hostnames: deinit called, module id is %d" % id)
    return True

def inform_super(id, qstate, superqstate, qdata):
    return True

def operate(id, event, qstate, qdata):
    log_info("module called with event %i" % event)
    haveAnswer = False

    if (event == MODULE_EVENT_NEW) or (event == MODULE_EVENT_PASS):
        qstate.ext_state[id] = MODULE_WAIT_MODULE 
        return True

    elif event == MODULE_EVENT_MODDONE:
        qname_str = qnameListToStr(qstate.qinfo.qname_list)
        log_info("python: MODDONE with rcode '%s' and priming '%s' and query '%s' of type '%s'" % (
                    qstate.return_rcode, qstate.is_priming, qname_str, qstate.qinfo.qtype_str
                ) )
        if (qstate.return_rcode == 0) and (qstate.return_msg.rep.an_numrrsets == 0):

            if ( pattern.match(qname_str) and ( qstate.qinfo.qtype_str == "A" ) ):
                log_info("python: Found AWS Hostname")
                ip = ((qname_str[3:]).split(".", 1)[0]).replace("-", ".")
                log_info("python: Real Answer is '%s 86400 IN A %s'" % (qname_str, ip) )
                msg = DNSMessage(qname_str, RR_TYPE_A, RR_CLASS_IN, PKT_QR | PKT_RA | PKT_AA)
                msg.answer.append("%s 86400 IN A %s" % ( qname_str, ip ) )
                log_info(" name %s, type %s, class %s, flags %s, ttl %s, q %s, a %s, auth %s, add %s " % (
                    msg.rr_name, msg.rr_type, msg.rr_class,
                    msg.query_flags, msg.default_ttl,
                    msg.question, msg.answer, msg.authority, msg.additional
                ) )

                qstate.ext_state[id] = MODULE_ERROR
                if not msg.set_return_msg(qstate):
                    log_info("set_return_msg ERROR")
                    return True

                qstate.return_msg.rep.security = 2
                qstate.return_rcode = RCODE_NOERROR
                qstate.ext_state[id] = MODULE_FINISHED
                return True
        qstate.ext_state[id] = MODULE_FINISHED
        return True

    log_err("pythonmod: Unknown event")
    qstate.ext_state[id] = MODULE_ERROR
    return True