#!/usr/bin/env python3
# Copyright 2018 AT&T Intellectual Property, Inc. All rights reserved.
# Copyright (c) 2019 Pantheon.tech. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
#  Author  Prakash Hosangady(ph553f)
#    DB Monitoring
#    Tracks Heartbeat messages on each of the VNFs stored in postgres DB
#    and generates Missing Heartbeat signal for Policy Engine

import math
import sched, datetime, time
import json
import string
import sys
import os
import logging
import socket
import requests
from . import htbtworker as pm
from . import misshtbtd as db
from . import get_logger

_logger = get_logger.get_logger(__name__)

def sendControlLoopEvent(CLType, pol_url,  policy_version, policy_name, policy_scope, target_type, srcName, epoc_time, closed_control_loop_name, version, target):
    msg="DBM:Time to raise Control Loop Event for Control loop typ /target type - ",CLType, target_type
    _logger.info(msg)
    if(CLType == "ONSET"):
        _logger.info("DBM:Heartbeat not received, raising alarm event")
        if(target_type == "VNF"):
            json_object = json.dumps({
                 "closedLoopEventClient": "DCAE_Heartbeat_MS",
                 "policyVersion": policy_version,
                 "policyName": policy_name,
                 "policyScope": policy_scope,
                 "target_type": target_type,
                 "AAI": { "generic-vnf.vnf-name": srcName} ,
                 "closedLoopAlarmStart": epoc_time,
                 "closedLoopEventStatus": "ONSET",
                 "closedLoopControlName": closed_control_loop_name,
                 "version": version,
                 "target": target,
                 "requestID": "8c1b8bd8-06f7-493f-8ed7-daaa4cc481bc",
                 "from": "DCAE"
                 });
        elif(target_type == "VM"):
            json_object = json.dumps({
                 "closedLoopEventClient": "DCAE_Heartbeat_MS",
                 "policyVersion": policy_version,
                 "policyName": policy_name,
                 "policyScope": policy_scope,
                 "target_type": target_type,
                 "AAI": { "vserver.vserver-name": srcName} ,
                 "closedLoopAlarmStart": epoc_time,
                 "closedLoopEventStatus": "ONSET",
                 "closedLoopControlName": closed_control_loop_name,
                 "version": version,
                 "target": target,
                 "requestID": "8c1b8bd8-06f7-493f-8ed7-daaa4cc481bc",
                 "from": "DCAE"
                 });
        else:
            return True
    elif(CLType == "ABATED"):
        _logger.info("DBM:Heartbeat received, clearing alarm event")
        #last_date_time = datetime.datetime.now()
        if(target_type == "VNF"):
            json_object = json.dumps({
                "closedLoopEventClient": "DCAE_Heartbeat_MS",
                "policyVersion": policy_version,
                "policyName": policy_name,
                "policyScope": policy_scope,
                "target_type": target_type,
                "AAI": { "generic-vnf.vnf-name": srcName} ,
                "closedLoopAlarmStart": epoc_time,
                "closedLoopEventStatus": "ABATED",
                "closedLoopControlName": closed_control_loop_name,
                "version": version,
                "target": target,
                "requestID": "8c1b8bd8-06f7-493f-8ed7-daaa4cc481bc",
                "from": "DCAE"
                });
        elif(target_type == "VM"):
            json_object = json.dumps({
                "closedLoopEventClient": "DCAE_Heartbeat_MS",
                "policyVersion": policy_version,
                "policyName": policy_name,
                "policyScope": policy_scope,
                "target_type": target_type,
                "AAI": { "vserver.vserver-name": srcName} ,
                "closedLoopAlarmStart": epoc_time,
                "closedLoopEventStatus": "ABATED",
                "closedLoopControlName": closed_control_loop_name,
                "version": version,
                "target": target,
                "requestID": "8c1b8bd8-06f7-493f-8ed7-daaa4cc481bc",
                "from": "DCAE"
                });
        else:
            return True
    else:
        return True
    payload = json_object
    msg="DBM: CL Json object is", json_object
    _logger.info(msg)
    #psend_url = pol_url+'DefaultGroup/1?timeout=15000'
    psend_url = pol_url
    msg="DBM:",psend_url
    _logger.info(msg)
    #Send response for policy on output topic
    try:
        r = requests.post(psend_url, data=payload)
        msg="DBM:",r.status_code, r.reason
        _logger.info(msg)
        ret = r.status_code
        msg="DBM:Status code for sending the control loop event is",ret
        _logger.info(msg)
    except(Exception) as err:
        msg='Message send failure : ', err
        _logger.error(msg)
    return True

def db_monitoring(current_pid,json_file,user_name,password,ip_address,port_num,db_name):
    while(True):
        time.sleep(20)

        envPytest = os.getenv('pytest', "")
        if (envPytest == 'test'):
           break

        try:
             with open(json_file, 'r') as outfile:
                  cfg = json.load(outfile)
             pol_url = str(cfg['streams_publishes']['dcae_cl_out']['dmaap_info']['topic_url'])
        except(Exception) as err:
             msg='Json file process error : ', err
             _logger.error(msg)
             continue

        hbc_pid, hbc_state, hbc_srcName, hbc_time = db.read_hb_common(user_name,password,ip_address,port_num,db_name)
        source_name = socket.gethostname()
        source_name = source_name + "-" + str(os.getenv('SERVICE_NAME', ""))
        connection_db = pm.postgres_db_open(user_name,password,ip_address,port_num,db_name)
        cur = connection_db.cursor()
        if(int(current_pid)==int(hbc_pid) and source_name==hbc_srcName and hbc_state == "RUNNING"):
            _logger.info("DBM: Active DB Monitoring Instance")
            db_query = "Select event_name from vnf_table_1"
            cur.execute(db_query)
            vnf_list = [item[0] for item in cur.fetchall()]
            for event_name in vnf_list:
                query_value = "SELECT current_state FROM hb_common;"
                cur.execute(query_value)
                rows = cur.fetchall()
                hbc_state = rows[0][0]
                if( hbc_state == "RECONFIGURATION"):
                    _logger.info("DBM:Waiting for hb_common state to become RUNNING")
                    break

                db_query = "Select validity_flag,source_name_count,heartbeat_interval,heartbeat_missed_count,closed_control_loop_name,policy_version, policy_name,policy_scope, target_type,target,version from vnf_table_1 where event_name= '%s'" %(event_name)
                cur.execute(db_query)
                rows = cur.fetchall()
                validity_flag = rows[0][0]
                source_name_count = rows[0][1]
                heartbeat_interval = rows[0][2]
                heartbeat_missed_count = rows[0][3]
                closed_control_loop_name = rows[0][4]
                policy_version = rows[0][5]
                policy_name = rows[0][6]
                policy_scope = rows[0][7]
                target_type = rows[0][8]
                target = rows[0][9]
                version = rows[0][10]
                comparision_time = (heartbeat_interval*heartbeat_missed_count)*1000
                if (validity_flag ==1):
                    for source_name_key in range(source_name_count):
                        epoc_time = int(round(time.time()*1000))
                        epoc_query = "Select last_epo_time,source_name,cl_flag from vnf_table_2 where event_name= '%s' and source_name_key=%d" %(event_name,(source_name_key+1))
                        cur.execute(epoc_query)
                        row = cur.fetchall()
                        if (len(row)==0):
                            continue
                        epoc_time_sec = row[0][0]
                        srcName = row[0][1]
                        cl_flag = row[0][2]
                        if((epoc_time-epoc_time_sec)>comparision_time and cl_flag ==0):
                            sendControlLoopEvent("ONSET", pol_url,  policy_version, policy_name, policy_scope, target_type, srcName, epoc_time, closed_control_loop_name, version, target)
                            cl_flag = 1
                            update_query = "UPDATE vnf_table_2 SET CL_FLAG=%d where EVENT_NAME ='%s' and source_name_key=%d" %(cl_flag,event_name,(source_name_key+1))
                            cur.execute(update_query)
                            connection_db.commit()
                        elif((epoc_time - epoc_time_sec) < comparision_time and cl_flag ==1):
                            sendControlLoopEvent("ABATED", pol_url,  policy_version, policy_name, policy_scope, target_type, srcName, epoc_time, closed_control_loop_name, version, target)
                            cl_flag = 0
                            update_query = "UPDATE vnf_table_2 SET CL_FLAG=%d where EVENT_NAME ='%s' and source_name_key=%d" %(cl_flag,event_name,(source_name_key+1))
                            cur.execute(update_query)
                            connection_db.commit()

                else:  #pragma: no cover
                    msg="DBM:DB Monitoring is ignored for %s since validity flag is 0" %(event_name)
                    _logger.info(msg)

                    delete_query_table2 = "DELETE FROM vnf_table_2 WHERE EVENT_NAME = '%s';" %(event_name)
                    cur.execute(delete_query_table2)
                    delete_query = "DELETE FROM vnf_table_1 WHERE EVENT_NAME = '%s';" %(event_name)
                    cur.execute(delete_query)
                    connection_db.commit()
                    """
                    Delete the VNF entry in table1 and delete all the source ids related to vnfs in table2
                    """
        else:  #pragma: no cover
            msg="DBM:Inactive instance or hb_common state is not RUNNING"
            _logger.info(msg)
        pm.commit_and_close_db(connection_db)
        cur.close()
        break;

if __name__ == "__main__":
    _logger.info("DBM: DBM Process started")
    current_pid = sys.argv[1]
    jsfile = sys.argv[2]
    ip_address, port_num, user_name, password, db_name, cbs_polling_required, cbs_polling_interval = db.read_hb_properties(jsfile)
    msg="DBM:Parent process ID and json file name",current_pid, jsfile
    _logger.info(msg)
    while (True):
        db_monitoring(current_pid,jsfile,user_name,password,ip_address,port_num,db_name)
        envPytest = os.getenv('pytest', "")
        if (envPytest == 'test'):
           break