#!/usr/bin/env python3
# Copyright 2018 AT&T Intellectual Property, Inc. 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 requests
import math
import sched, datetime, time
import json
import string
import sys
import os
import socket
import requests
import htbtworker as pm
import misshtbtd as db
import logging
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