back/pialert.py

#!/usr/bin/env python
#
#-------------------------------------------------------------------------------
#  Pi.Alert  v2.70  /  2021-02-01
#  Open Source Network Guard / WIFI & LAN intrusion detector 
#
#  pialert.py - Back module. Network scanner
#-------------------------------------------------------------------------------
#  Puche 2021        pi.alert.application@gmail.com        GNU GPLv3
#-------------------------------------------------------------------------------


#===============================================================================
# IMPORTS
#===============================================================================
from __future__ import print_function
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText

import sys
import subprocess
import os
import re
import datetime
import sqlite3
import socket
import io
import smtplib
import csv


#===============================================================================
# CONFIG CONSTANTS
#===============================================================================
PIALERT_BACK_PATH = os.path.dirname(os.path.abspath(__file__))
PIALERT_PATH = PIALERT_BACK_PATH + "/.."

if (sys.version_info > (3,0)):
    exec(open(PIALERT_PATH + "/config/version.conf").read())
    exec(open(PIALERT_PATH + "/config/pialert.conf").read())
else:
    execfile (PIALERT_PATH + "/config/version.conf")
    execfile (PIALERT_PATH + "/config/pialert.conf")


#===============================================================================
# MAIN
#===============================================================================
def main ():
    global startTime
    global cycle
    global log_timestamp
    global sql_connection
    global sql

    # Header
    print ('\nPi.Alert ' + VERSION +' ('+ VERSION_DATE +')')
    print ('---------------------------------------------------------')

    # Initialize global variables
    log_timestamp  = datetime.datetime.now()

    # DB
    sql_connection = None
    sql            = None

    # Timestamp
    startTime = datetime.datetime.now()
    startTime = startTime.replace (second=0, microsecond=0)

    # Check parameters
    if len(sys.argv) != 2 :
        print ('usage pialert [scan_cycle] | internet_IP | update_vendors' )
        return
    cycle = str(sys.argv[1])

    ## Main Commands
    if cycle == 'internet_IP':
        res = check_internet_IP()
    elif cycle == 'update_vendors':
        res = update_devices_MAC_vendors()
    elif cycle == 'update_vendors_silent':
        res = update_devices_MAC_vendors('-s')
    else :
        res = scan_network()
    
    # Check error
    if res != 0 :
        closeDB()
        return res
    
    # Reporting
    if cycle != 'internet_IP':
        email_reporting()

    # Close SQL
    closeDB()
    closeDB()

    # Final menssage
    print ('\nDONE!!!\n\n')
    return 0    

    
#===============================================================================
# INTERNET IP CHANGE
#===============================================================================
def check_internet_IP ():
    # Header
    print ('Check Internet IP')
    print ('    Timestamp:', startTime )

    # Get Internet IP
    print ('\nRetrieving Internet IP...')
    internet_IP = get_internet_IP()
    # TESTING - Force IP
        # internet_IP = "1.2.3.4"

    # Check result = IP
    if internet_IP == "" :
        print ('    Error retrieving Internet IP')
        print ('    Exiting...\n')
        return 1
    print ('   ', internet_IP)

    # Get previous stored IP
    print ('\nRetrieving previous IP...')
    openDB()
    previous_IP = get_previous_internet_IP ()
    print ('   ', previous_IP)

    # Check IP Change
    if internet_IP != previous_IP :
        print ('    Saving new IP')
        save_new_internet_IP (internet_IP)
        print ('        IP updated')
    else :
        print ('    No changes to perform')
    closeDB()

    # Get Dynamic DNS IP
    if DDNS_ACTIVE :
        print ('\nRetrieving Dynamic DNS IP...')
        dns_IP = get_dynamic_DNS_IP()

        # Check Dynamic DNS IP
        if dns_IP == "" :
            print ('    Error retrieving Dynamic DNS IP')
            print ('    Exiting...\n')
            return 1
        print ('   ', dns_IP)

        # Check DNS Change
        if dns_IP != internet_IP :
            print ('    Updating Dynamic DNS IP...')
            message = set_dynamic_DNS_IP ()
            print ('       ', message)
        else :
            print ('    No changes to perform')
    else :
        print ('\nSkipping Dynamic DNS update...')

    # OK
    return 0

#-------------------------------------------------------------------------------
def get_internet_IP ():
    # BUGFIX #46 - curl http://ipv4.icanhazip.com repeatedly is very slow
    # Using 'dig'
    dig_args = ['dig', '+short', '-4', 'myip.opendns.com', '@resolver1.opendns.com']
    cmd_output = subprocess.check_output (dig_args, universal_newlines=True)

    ## BUGFIX #12 - Query IPv4 address (not IPv6)
    ## Using 'curl' instead of 'dig'
    ## curl_args = ['curl', '-s', 'https://diagnostic.opendns.com/myip']
    #curl_args = ['curl', '-s', QUERY_MYIP_SERVER]
    #cmd_output = subprocess.check_output (curl_args, universal_newlines=True)

    # Check result is an IP
    IP = check_IP_format (cmd_output)
    return IP

#-------------------------------------------------------------------------------
def get_dynamic_DNS_IP ():
    # Using OpenDNS server
        # dig_args = ['dig', '+short', DDNS_DOMAIN, '@resolver1.opendns.com']

    # Using default DNS server
    dig_args = ['dig', '+short', DDNS_DOMAIN]
    dig_output = subprocess.check_output (dig_args, universal_newlines=True)

    # Check result is an IP
    IP = check_IP_format (dig_output)
    return IP

#-------------------------------------------------------------------------------
def set_dynamic_DNS_IP ():
    # Update Dynamic IP
    curl_output = subprocess.check_output (['curl', '-s',
        DDNS_UPDATE_URL +
        'username='  + DDNS_USER +
        '&password=' + DDNS_PASSWORD +
        '&hostname=' + DDNS_DOMAIN],
        universal_newlines=True)
    return curl_output
    
#-------------------------------------------------------------------------------
def get_previous_internet_IP ():
    # get previos internet IP stored in DB
    sql.execute ("SELECT dev_LastIP FROM Devices WHERE dev_MAC = 'Internet' ")
    previous_IP = sql.fetchone()[0]

    # return previous IP
    return previous_IP

#-------------------------------------------------------------------------------
def save_new_internet_IP (pNewIP):
    # Log new IP into logfile
    append_line_to_file (LOG_PATH + '/IP_changes.log',
        str(startTime) +'\t'+ pNewIP +'\n')

    # Save event
    sql.execute ("""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    VALUES ('Internet', ?, ?, 'Internet IP Changed',
                        'Previous Internet IP: '|| ?, 1) """,
                    (pNewIP, startTime, get_previous_internet_IP() ) )

    # Save new IP
    sql.execute ("""UPDATE Devices SET dev_LastIP = ?
                    WHERE dev_MAC = 'Internet' """,
                    (pNewIP,) )

    # commit changes
    sql_connection.commit()
    
#-------------------------------------------------------------------------------
def check_IP_format (pIP):
    # Check IP format
    IPv4SEG  = r'(?:25[0-5]|(?:2[0-4]|1{0,1}[0-9]){0,1}[0-9])'
    IPv4ADDR = r'(?:(?:' + IPv4SEG + r'\.){3,3}' + IPv4SEG + r')'
    IP = re.search(IPv4ADDR, pIP)

    # Return error if not IP
    if IP is None :
        return ""

    # Return IP
    return IP.group(0)


#===============================================================================
# UPDATE DEVICE MAC VENDORS
#===============================================================================
def update_devices_MAC_vendors (pArg = ''):
    # Header
    print ('Update HW Vendors')
    print ('    Timestamp:', startTime )

    # Update vendors DB (iab oui)
    print ('\nUpdating vendors DB (iab & oui)...')
    update_args = ['sh', PIALERT_BACK_PATH + '/update_vendors.sh', pArg]
    update_output = subprocess.check_output (update_args)
    # DEBUG
        # update_args = ['./vendors_db_update.sh']
        # subprocess.call (update_args, shell=True)

    # Initialize variables
    recordsToUpdate = []
    ignored = 0
    notFound = 0

    # All devices loop
    print ('\nSearching devices vendor', end='')
    openDB()
    for device in sql.execute ("SELECT * FROM Devices") :
        # Search vendor in HW Vendors DB
        vendor = query_MAC_vendor (device['dev_MAC'])
        if vendor == -1 :
            notFound += 1
        elif vendor == -2 :
            ignored += 1
        else :
            recordsToUpdate.append ([vendor, device['dev_MAC']])
        # progress bar
        print ('.', end='')
        sys.stdout.flush()
            
    # Print log
    print ('')
    print ("    Devices Ignored:  ", ignored)
    print ("    Vendors Not Found:", notFound)
    print ("    Vendors updated:  ", len(recordsToUpdate) )
    # DEBUG - print list of record to update
        # print (recordsToUpdate)

    # update devices
    sql.executemany ("UPDATE Devices SET dev_Vendor = ? WHERE dev_MAC = ? ",
        recordsToUpdate )

    # DEBUG - print number of rows updated
        # print (sql.rowcount)

    # Close DB
    closeDB()

#-------------------------------------------------------------------------------
def query_MAC_vendor (pMAC):
    try :
        # BUGFIX #6 - Fix pMAC parameter as numbers
        pMACstr = str(pMAC)
        
        # Check MAC parameter
        mac = pMACstr.replace (':','')
        if len(pMACstr) != 17 or len(mac) != 12 :
            return -2

        # Search vendor in HW Vendors DB
        mac = mac[0:6]
        grep_args = ['grep', '-i', mac, VENDORS_DB]
        grep_output = subprocess.check_output (grep_args)

        # Return Vendor
        vendor = grep_output[7:]
        vendor = vendor.rstrip()
        return vendor

    # not Found
    except subprocess.CalledProcessError :
        return -1
            
#===============================================================================
# SCAN NETWORK
#===============================================================================
def scan_network ():
    # Header
    print ('Scan Devices')
    print ('    ScanCycle:', cycle)
    print ('    Timestamp:', startTime )

    # Query ScanCycle properties
    print_log ('Query ScanCycle confinguration...')
    scanCycle_data = query_ScanCycle_Data (True)
    if scanCycle_data is None:
        print ('\n*************** ERROR ***************')
        print ('ScanCycle %s not found' % cycle )
        print ('    Exiting...\n')
        return 1

    # ScanCycle data        
    cycle_interval  = scanCycle_data['cic_EveryXmin']
    arpscan_retries = scanCycle_data['cic_arpscanCycles']
    # TESTING - Fast scan
        # arpscan_retries = 1
    
    # arp-scan command
    print ('\nScanning...')
    print ('    arp-scan Method...')
    print_log ('arp-scan starts...')
    arpscan_devices = execute_arpscan (arpscan_retries)
    print_log ('arp-scan ends')
    # DEBUG - print number of rows updated
        # print (arpscan_devices)

    # Pi-hole method
    print ('    Pi-hole Method...')
    openDB()
    print_log ('Pi-hole copy starts...')
    copy_pihole_network()

    # DHCP Leases method
    print ('    DHCP Leases Method...')
    read_DHCP_leases ()

    # Load current scan data
    print ('\nProcessing scan results...')
    print_log ('Save scanned devices')
    save_scanned_devices (arpscan_devices, cycle_interval)
    
    # Print stats
    print_log ('Print Stats')
    print_scan_stats()
    print_log ('Stats end')

    # Create Events
    print ('\nUpdating DB Info...')
    print ('    Sessions Events (connect / discconnect) ...')
    insert_events()

    # Create New Devices
    # after create events -> avoid 'connection' event
    print ('    Creating new devices...')
    create_new_devices ()

    # Update devices info
    print ('    Updating Devices Info...')
    update_devices_data_from_scan ()

    # Resolve devices names
    print_log ('   Resolve devices names...')
    update_devices_names()

    # Void false connection - disconnections
    print ('    Voiding false (ghost) disconnections...')
    void_ghost_disconnections ()
  
    # Pair session events (Connection / Disconnection)
    print ('    Pairing session events (connection / disconnection) ...')
    pair_sessions_events()  
  
    # Sessions snapshot
    print ('    Creating sessions snapshot...')
    create_sessions_snapshot ()
  
    # Skip repeated notifications
    print ('    Skipping repeated notifications...')
    skip_repeated_notifications ()
  
    # Commit changes
    sql_connection.commit()
    closeDB()

    # OK
    return 0

#-------------------------------------------------------------------------------
def query_ScanCycle_Data (pOpenCloseDB = False):
    # Check if is necesary open DB
    if pOpenCloseDB :
        openDB()

    # Query Data
    sql.execute ("""SELECT cic_arpscanCycles, cic_EveryXmin
                    FROM ScanCycles
                    WHERE cic_ID = ? """, (cycle,))
    sqlRow = sql.fetchone()

    # Check if is necesary close DB
    if pOpenCloseDB :
        closeDB()

    # Return Row
    return sqlRow

#-------------------------------------------------------------------------------
def execute_arpscan (pRetries):
 
    # #101 - arp-scan subnet configuration
    # Prepare command arguments
    subnets = SCAN_SUBNETS.strip().split()
    arpscan_args = ['sudo', 'arp-scan', '--ignoredups', '--retry=' + str(pRetries)] + subnets
    # arpscan_args = ['sudo', 'arp-scan', SCAN_SUBNETS, '--ignoredups', '--retry=' + str(pRetries)]
    # print (arpscan_args)

    # TESTING - Fast Scan
        # arpscan_args = ['sudo', 'arp-scan', '--localnet', '--ignoredups', '--retry=1']

    # DEBUG - arp-scan command
        # print (" ".join (arpscan_args))

    # Execute command
    arpscan_output = subprocess.check_output (arpscan_args, universal_newlines=True)

    # Search IP + MAC + Vendor as regular expresion
    re_ip = r'(?P<ip>((2[0-5]|1[0-9]|[0-9])?[0-9]\.){3}((2[0-5]|1[0-9]|[0-9])?[0-9]))'
    re_mac = r'(?P<mac>([0-9a-fA-F]{2}[:-]){5}([0-9a-fA-F]{2}))'
    re_hw = r'(?P<hw>.*)'
    re_pattern = re.compile (re_ip + '\s+' + re_mac + '\s' + re_hw)

    # Create Userdict of devices
    devices_list = [device.groupdict()
        for device in re.finditer (re_pattern, arpscan_output)]

    # Bugfix #5 - Delete duplicated MAC's with different IP's
    # TEST - Force duplicated device
        # devices_list.append(devices_list[0])
    # Delete duplicate MAC
    unique_mac = [] 
    unique_devices = [] 

    for device in devices_list :
        if device['mac'] not in unique_mac: 
            unique_mac.append(device['mac'])
            unique_devices.append(device)

    # DEBUG
        # print (devices_list)
        # print (unique_mac)
        # print (unique_devices)
        # print (len(devices_list))
        # print (len(unique_mac))
        # print (len(unique_devices))

    # return list
    return unique_devices

#-------------------------------------------------------------------------------
def copy_pihole_network ():
    # check if Pi-hole is active
    if not PIHOLE_ACTIVE :
        return    

    # Open Pi-hole DB
    sql.execute ("ATTACH DATABASE '"+ PIHOLE_DB +"' AS PH")

    # Copy Pi-hole Network table
    sql.execute ("DELETE FROM PiHole_Network")
    sql.execute ("""INSERT INTO PiHole_Network (PH_MAC, PH_Vendor, PH_LastQuery,
                        PH_Name, PH_IP)
                    SELECT hwaddr, macVendor, lastQuery,
                        (SELECT name FROM PH.network_addresses
                         WHERE network_id = id ORDER BY lastseen DESC, ip),
                        (SELECT ip FROM PH.network_addresses
                         WHERE network_id = id ORDER BY lastseen DESC, ip)
                    FROM PH.network
                    WHERE hwaddr NOT LIKE 'ip-%'
                      AND hwaddr <> '00:00:00:00:00:00' """)
    sql.execute ("""UPDATE PiHole_Network SET PH_Name = '(unknown)'
                    WHERE PH_Name IS NULL OR PH_Name = '' """)
    # DEBUG
        # print (sql.rowcount)

    # Close Pi-hole DB
    sql.execute ("DETACH PH")

#-------------------------------------------------------------------------------
def read_DHCP_leases ():
    # check DHCP Leases is active
    if not DHCP_ACTIVE :
        return    
            
    # Read DHCP Leases
    # Bugfix #1 - dhcp.leases: lines with different number of columns (5 col)
    data = []
    with open(DHCP_LEASES, 'r') as f:
        for line in f:
            row = line.rstrip().split()
            if len(row) == 5 :
                data.append (row)
    # with open(DHCP_LEASES) as f:
    #    reader = csv.reader(f, delimiter=' ')
    #    data = [(col1, col2, col3, col4, col5)
    #            for col1, col2, col3, col4, col5 in reader]

    # Insert into PiAlert table
    sql.execute ("DELETE FROM DHCP_Leases")
    sql.executemany ("""INSERT INTO DHCP_Leases (DHCP_DateTime, DHCP_MAC,
                            DHCP_IP, DHCP_Name, DHCP_MAC2)
                        VALUES (?, ?, ?, ?, ?)
                     """, data)
    # DEBUG
        # print (sql.rowcount)

#-------------------------------------------------------------------------------
def save_scanned_devices (p_arpscan_devices, p_cycle_interval):
    # Delete previous scan data
    sql.execute ("DELETE FROM CurrentScan WHERE cur_ScanCycle = ?",
                (cycle,))

    # Insert new arp-scan devices
    sql.executemany ("INSERT INTO CurrentScan (cur_ScanCycle, cur_MAC, "+
                     "    cur_IP, cur_Vendor, cur_ScanMethod) "+
                     "VALUES ("+ cycle + ", :mac, :ip, :hw, 'arp-scan')",
                     p_arpscan_devices) 

    # Insert Pi-hole devices
    sql.execute ("""INSERT INTO CurrentScan (cur_ScanCycle, cur_MAC, 
                        cur_IP, cur_Vendor, cur_ScanMethod)
                    SELECT ?, PH_MAC, PH_IP, PH_Vendor, 'Pi-hole'
                    FROM PiHole_Network
                    WHERE PH_LastQuery >= ?
                      AND NOT EXISTS (SELECT 'X' FROM CurrentScan
                                      WHERE cur_MAC = PH_MAC
                                        AND cur_ScanCycle = ? )""",
                    (cycle,
                     (int(startTime.strftime('%s')) - 60 * p_cycle_interval),
                     cycle) )

    # Check Internet connectivity
    internet_IP = get_internet_IP()
        # TESTING - Force IP
        # internet_IP = ""
    if internet_IP != "" :
        sql.execute ("""INSERT INTO CurrentScan (cur_ScanCycle, cur_MAC, cur_IP, cur_Vendor, cur_ScanMethod)
                        VALUES (?, 'Internet', ?, Null, 'queryDNS') """, (cycle, internet_IP) )

    # #76 Add Local MAC of default local interface
      # BUGFIX #106 - Device that pialert is running
        # local_mac_cmd = ["bash -lc ifconfig `ip route list default | awk {'print $5'}` | grep ether | awk '{print $2}'"]
          # local_mac_cmd = ["/sbin/ifconfig `ip route list default | sort -nk11 | head -1 | awk {'print $5'}` | grep ether | awk '{print $2}'"]
    local_mac_cmd = ["/sbin/ifconfig `ip -o route get 1 | sed 's/^.*dev \\([^ ]*\\).*$/\\1/;q'` | grep ether | awk '{print $2}'"]
    local_mac = subprocess.Popen (local_mac_cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT).communicate()[0].decode().strip()

    # local_dev_cmd = ["ip -o route get 1 | sed 's/^.*dev \\([^ ]*\\).*$/\\1/;q'"]
    # local_dev = subprocess.Popen (local_dev_cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT).communicate()[0].decode().strip()
    
    # local_ip_cmd = ["ip route list default | awk {'print $7'}"]
    local_ip_cmd = ["ip -o route get 1 | sed 's/^.*src \\([^ ]*\\).*$/\\1/;q'"]
    local_ip = subprocess.Popen (local_ip_cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT).communicate()[0].decode().strip()

    # Check if local mac has been detected with other methods
    sql.execute ("SELECT COUNT(*) FROM CurrentScan WHERE cur_ScanCycle = ? AND cur_MAC = ? ", (cycle, local_mac) )
    if sql.fetchone()[0] == 0 :
        sql.execute ("INSERT INTO CurrentScan (cur_ScanCycle, cur_MAC, cur_IP, cur_Vendor, cur_ScanMethod) "+
                     "VALUES ( ?, ?, ?, Null, 'local_MAC') ", (cycle, local_mac, local_ip) )

#-------------------------------------------------------------------------------
def print_scan_stats ():
    # Devices Detected
    sql.execute ("""SELECT COUNT(*) FROM CurrentScan
                    WHERE cur_ScanCycle = ? """,
                    (cycle,))
    print ('    Devices Detected.......:', str (sql.fetchone()[0]) )

    # Devices arp-scan
    sql.execute ("""SELECT COUNT(*) FROM CurrentScan
                    WHERE cur_ScanMethod='arp-scan' AND cur_ScanCycle = ? """,
                    (cycle,))
    print ('        arp-scan Method....:', str (sql.fetchone()[0]) )

    # Devices Pi-hole
    sql.execute ("""SELECT COUNT(*) FROM CurrentScan
                    WHERE cur_ScanMethod='PiHole' AND cur_ScanCycle = ? """,
                    (cycle,))
    print ('        Pi-hole Method.....: +' + str (sql.fetchone()[0]) )

    # New Devices
    sql.execute ("""SELECT COUNT(*) FROM CurrentScan
                    WHERE cur_ScanCycle = ? 
                      AND NOT EXISTS (SELECT 1 FROM Devices
                                      WHERE dev_MAC = cur_MAC) """,
                    (cycle,))
    print ('        New Devices........: ' + str (sql.fetchone()[0]) )

    # Devices in this ScanCycle
    sql.execute ("""SELECT COUNT(*) FROM Devices, CurrentScan
                    WHERE dev_MAC = cur_MAC AND dev_ScanCycle = cur_ScanCycle
                      AND dev_ScanCycle = ? """,
                    (cycle,))
    print ('')
    print ('    Devices in this cycle..: ' + str (sql.fetchone()[0]) )

    # Down Alerts
    sql.execute ("""SELECT COUNT(*) FROM Devices
                    WHERE dev_AlertDeviceDown = 1
                      AND dev_ScanCycle = ?
                      AND NOT EXISTS (SELECT 1 FROM CurrentScan
                                      WHERE dev_MAC = cur_MAC
                                        AND dev_ScanCycle = cur_ScanCycle) """,
                    (cycle,))
    print ('        Down Alerts........: ' + str (sql.fetchone()[0]) )

    # New Down Alerts
    sql.execute ("""SELECT COUNT(*) FROM Devices
                    WHERE dev_AlertDeviceDown = 1
                      AND dev_PresentLastScan = 1
                      AND dev_ScanCycle = ?
                      AND NOT EXISTS (SELECT 1 FROM CurrentScan
                                      WHERE dev_MAC = cur_MAC
                                        AND dev_ScanCycle = cur_ScanCycle) """,
                    (cycle,))
    print ('        New Down Alerts....: ' + str (sql.fetchone()[0]) )

    # New Connections
    sql.execute ("""SELECT COUNT(*) FROM Devices, CurrentScan
                    WHERE dev_MAC = cur_MAC AND dev_ScanCycle = cur_ScanCycle
                      AND dev_PresentLastScan = 0
                      AND dev_ScanCycle = ? """,
                    (cycle,))
    print ('        New Connections....: ' + str ( sql.fetchone()[0]) )

    # Disconnections
    sql.execute ("""SELECT COUNT(*) FROM Devices
                    WHERE dev_PresentLastScan = 1
                      AND dev_ScanCycle = ?
                      AND NOT EXISTS (SELECT 1 FROM CurrentScan
                                      WHERE dev_MAC = cur_MAC
                                        AND dev_ScanCycle = cur_ScanCycle) """,
                    (cycle,))
    print ('        Disconnections.....: ' + str ( sql.fetchone()[0]) )

    # IP Changes
    sql.execute ("""SELECT COUNT(*) FROM Devices, CurrentScan
                    WHERE dev_MAC = cur_MAC AND dev_ScanCycle = cur_ScanCycle
                      AND dev_ScanCycle = ?
                      AND dev_LastIP <> cur_IP """,
                    (cycle,))
    print ('        IP Changes.........: ' + str ( sql.fetchone()[0]) )

#-------------------------------------------------------------------------------
def create_new_devices ():
    # arpscan - Insert events for new devices
    print_log ('New devices - 1 Events')
    sql.execute ("""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    SELECT cur_MAC, cur_IP, ?, 'New Device', cur_Vendor, 1
                    FROM CurrentScan
                    WHERE cur_ScanCycle = ? 
                      AND NOT EXISTS (SELECT 1 FROM Devices
                                      WHERE dev_MAC = cur_MAC) """,
                    (startTime, cycle) ) 

    # arpscan - Create new devices
    print_log ('New devices - 2 Create devices')
    sql.execute ("""INSERT INTO Devices (dev_MAC, dev_name, dev_Vendor,
                        dev_LastIP, dev_FirstConnection, dev_LastConnection,
                        dev_ScanCycle, dev_AlertEvents, dev_AlertDeviceDown,
                        dev_PresentLastScan)
                    SELECT cur_MAC, '(unknown)', cur_Vendor, cur_IP, ?, ?,
                        1, 1, 0, 1
                    FROM CurrentScan
                    WHERE cur_ScanCycle = ? 
                      AND NOT EXISTS (SELECT 1 FROM Devices
                                      WHERE dev_MAC = cur_MAC) """,
                    (startTime, startTime, cycle) ) 

    # Pi-hole - Insert events for new devices
    # NOT STRICYLY NECESARY (Devices can be created through Current_Scan)
    # Bugfix #2 - Pi-hole devices w/o IP
    print_log ('New devices - 3 Pi-hole Events')
    sql.execute ("""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    SELECT PH_MAC, IFNULL (PH_IP,'-'), ?, 'New Device',
                        '(Pi-Hole) ' || PH_Vendor, 1
                    FROM PiHole_Network
                    WHERE NOT EXISTS (SELECT 1 FROM Devices
                                      WHERE dev_MAC = PH_MAC) """,
                    (startTime, ) ) 

    # Pi-hole - Create New Devices
    # Bugfix #2 - Pi-hole devices w/o IP
    print_log ('New devices - 4 Pi-hole Create devices')
    sql.execute ("""INSERT INTO Devices (dev_MAC, dev_name, dev_Vendor,
                        dev_LastIP, dev_FirstConnection, dev_LastConnection,
                        dev_ScanCycle, dev_AlertEvents, dev_AlertDeviceDown,
                        dev_PresentLastScan)
                    SELECT PH_MAC, PH_Name, PH_Vendor, IFNULL (PH_IP,'-'),
                        ?, ?, 1, 1, 0, 1
                    FROM PiHole_Network
                    WHERE NOT EXISTS (SELECT 1 FROM Devices
                                      WHERE dev_MAC = PH_MAC) """,
                    (startTime, startTime) ) 

    # DHCP Leases - Insert events for new devices
    print_log ('New devices - 5 DHCP Leases Events')
    sql.execute ("""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    SELECT DHCP_MAC, DHCP_IP, ?, 'New Device', '(DHCP lease)',1
                    FROM DHCP_Leases
                    WHERE NOT EXISTS (SELECT 1 FROM Devices
                                      WHERE dev_MAC = DHCP_MAC) """,
                    (startTime, ) ) 

    # DHCP Leases - Create New Devices
    print_log ('New devices - 6 DHCP Leases Create devices')
    # BUGFIX #23 - Duplicated MAC in DHCP.Leases
    # TEST - Force Duplicated MAC
        # sql.execute ("""INSERT INTO DHCP_Leases VALUES
        #                 (1610700000, 'TEST1', '10.10.10.1', 'Test 1', '*')""")
        # sql.execute ("""INSERT INTO DHCP_Leases VALUES
        #                 (1610700000, 'TEST2', '10.10.10.2', 'Test 2', '*')""")
    sql.execute ("""INSERT INTO Devices (dev_MAC, dev_name, dev_LastIP, 
                        dev_Vendor, dev_FirstConnection, dev_LastConnection,
                        dev_ScanCycle, dev_AlertEvents, dev_AlertDeviceDown,
                        dev_PresentLastScan)
                    SELECT DISTINCT DHCP_MAC,
                        (SELECT DHCP_Name FROM DHCP_Leases AS D2
                         WHERE D2.DHCP_MAC = D1.DHCP_MAC
                         ORDER BY DHCP_DateTime DESC LIMIT 1),
                        (SELECT DHCP_IP FROM DHCP_Leases AS D2
                         WHERE D2.DHCP_MAC = D1.DHCP_MAC
                         ORDER BY DHCP_DateTime DESC LIMIT 1),
                        '(unknown)', ?, ?, 1, 1, 0, 1
                    FROM DHCP_Leases AS D1
                    WHERE NOT EXISTS (SELECT 1 FROM Devices
                                      WHERE dev_MAC = DHCP_MAC) """,
                    (startTime, startTime) ) 

    # sql.execute ("""INSERT INTO Devices (dev_MAC, dev_name, dev_Vendor,
    #                     dev_LastIP, dev_FirstConnection, dev_LastConnection,
    #                     dev_ScanCycle, dev_AlertEvents, dev_AlertDeviceDown,
    #                     dev_PresentLastScan)
    #                 SELECT DHCP_MAC, DHCP_Name, '(unknown)', DHCP_IP, ?, ?,
    #                     1, 1, 0, 1
    #                 FROM DHCP_Leases
    #                 WHERE NOT EXISTS (SELECT 1 FROM Devices
    #                                   WHERE dev_MAC = DHCP_MAC) """,
    #                 (startTime, startTime) ) 
    print_log ('New Devices end')

#-------------------------------------------------------------------------------
def insert_events ():
    # Check device down
    print_log ('Events 1 - Devices down')
    sql.execute ("""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    SELECT dev_MAC, dev_LastIP, ?, 'Device Down', '', 1
                    FROM Devices
                    WHERE dev_AlertDeviceDown = 1
                      AND dev_PresentLastScan = 1
                      AND dev_ScanCycle = ?
                      AND NOT EXISTS (SELECT 1 FROM CurrentScan
                                      WHERE dev_MAC = cur_MAC
                                        AND dev_ScanCycle = cur_ScanCycle) """,
                    (startTime, cycle) )

    # Check new connections
    print_log ('Events 2 - New Connections')
    sql.execute ("""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    SELECT cur_MAC, cur_IP, ?, 'Connected', '', dev_AlertEvents
                    FROM Devices, CurrentScan
                    WHERE dev_MAC = cur_MAC AND dev_ScanCycle = cur_ScanCycle
                      AND dev_PresentLastScan = 0
                      AND dev_ScanCycle = ? """,
                    (startTime, cycle) )

    # Check disconnections
    print_log ('Events 3 - Disconnections')
    sql.execute ("""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    SELECT dev_MAC, dev_LastIP, ?, 'Disconnected', '',
                        dev_AlertEvents
                    FROM Devices
                    WHERE dev_AlertDeviceDown = 0
                      AND dev_PresentLastScan = 1
                      AND dev_ScanCycle = ?
                      AND NOT EXISTS (SELECT 1 FROM CurrentScan
                                      WHERE dev_MAC = cur_MAC
                                        AND dev_ScanCycle = cur_ScanCycle) """,
                    (startTime, cycle) )

    # Check IP Changed
    print_log ('Events 4 - IP Changes')
    sql.execute ("""INSERT INTO Events (eve_MAC, eve_IP, eve_DateTime,
                        eve_EventType, eve_AdditionalInfo,
                        eve_PendingAlertEmail)
                    SELECT cur_MAC, cur_IP, ?, 'IP Changed',
                        'Previous IP: '|| dev_LastIP, dev_AlertEvents
                    FROM Devices, CurrentScan
                    WHERE dev_MAC = cur_MAC AND dev_ScanCycle = cur_ScanCycle
                      AND dev_ScanCycle = ?
                      AND dev_LastIP <> cur_IP """,
                    (startTime, cycle) )
    print_log ('Events end')

#-------------------------------------------------------------------------------
def update_devices_data_from_scan ():
    # Update Last Connection
    print_log ('Update devices - 1 Last Connection')
    sql.execute ("""UPDATE Devices SET dev_LastConnection = ?,
                        dev_PresentLastScan = 1
                    WHERE dev_ScanCycle = ?
                      AND dev_PresentLastScan = 0
                      AND EXISTS (SELECT 1 FROM CurrentScan 
                                  WHERE dev_MAC = cur_MAC
                                    AND dev_ScanCycle = cur_ScanCycle) """,
                    (startTime, cycle))

    # Clean no active devices
    print_log ('Update devices - 2 Clean no active devices')
    sql.execute ("""UPDATE Devices SET dev_PresentLastScan = 0
                    WHERE dev_ScanCycle = ?
                      AND NOT EXISTS (SELECT 1 FROM CurrentScan 
                                      WHERE dev_MAC = cur_MAC
                                        AND dev_ScanCycle = cur_ScanCycle) """,
                    (cycle,))

    # Update IP & Vendor
    print_log ('Update devices - 3 LastIP & Vendor')
    sql.execute ("""UPDATE Devices
                    SET dev_LastIP = (SELECT cur_IP FROM CurrentScan
                                      WHERE dev_MAC = cur_MAC
                                        AND dev_ScanCycle = cur_ScanCycle),
                        dev_Vendor = (SELECT cur_Vendor FROM CurrentScan
                                      WHERE dev_MAC = cur_MAC
                                        AND dev_ScanCycle = cur_ScanCycle)
                    WHERE dev_ScanCycle = ?
                      AND EXISTS (SELECT 1 FROM CurrentScan
                                  WHERE dev_MAC = cur_MAC
                                    AND dev_ScanCycle = cur_ScanCycle) """,
                    (cycle,)) 

    # Pi-hole Network - Update (unknown) Name
    print_log ('Update devices - 4 Unknown Name')
    sql.execute ("""UPDATE Devices
                    SET dev_NAME = (SELECT PH_Name FROM PiHole_Network
                                    WHERE PH_MAC = dev_MAC)
                    WHERE (dev_Name = "(unknown)"
                           OR dev_Name = ""
                           OR dev_Name IS NULL)
                      AND EXISTS (SELECT 1 FROM PiHole_Network
                                  WHERE PH_MAC = dev_MAC
                                    AND PH_NAME IS NOT NULL
                                    AND PH_NAME <> '') """)

    # DHCP Leases - Update (unknown) Name
    sql.execute ("""UPDATE Devices
                    SET dev_NAME = (SELECT DHCP_Name FROM DHCP_Leases
                                    WHERE DHCP_MAC = dev_MAC)
                    WHERE (dev_Name = "(unknown)"
                           OR dev_Name = ""
                           OR dev_Name IS NULL)
                      AND EXISTS (SELECT 1 FROM DHCP_Leases
                                  WHERE DHCP_MAC = dev_MAC)""")

    # DHCP Leases - Vendor
    print_log ('Update devices - 5 Vendor')

    recordsToUpdate = []
    query = """SELECT * FROM Devices
               WHERE dev_Vendor = '(unknown)' OR dev_Vendor =''
                  OR dev_Vendor IS NULL"""

    for device in sql.execute (query) :
        vendor = query_MAC_vendor (device['dev_MAC'])
        if vendor != -1 and vendor != -2 :
            recordsToUpdate.append ([vendor, device['dev_MAC']])

    # DEBUG - print list of record to update
        # print (recordsToUpdate)
    sql.executemany ("UPDATE Devices SET dev_Vendor = ? WHERE dev_MAC = ? ",
        recordsToUpdate )

    # New Apple devices -> Cycle 15
    print_log ('Update devices - 6 Cycle for Apple devices')
    sql.execute ("""UPDATE Devices SET dev_ScanCycle = 15
                    WHERE dev_FirstConnection = ?
                      AND UPPER(dev_Vendor) LIKE '%APPLE%' """,
                (startTime,) )

    print_log ('Update devices end')

#-------------------------------------------------------------------------------
# Feature #43 - Resoltion name for unknown devices
def update_devices_names ():
    # Initialize variables
    recordsToUpdate = []
    ignored = 0
    notFound = 0

    # Devices without name
    print ('        Trying to resolve devices without name...', end='')
    # BUGFIX #97 - Updating name of Devices w/o IP
    for device in sql.execute ("SELECT * FROM Devices WHERE dev_Name IN ('(unknown)','') AND dev_LastIP <> '-'") :
        # Resolve device name
        newName = resolve_device_name (device['dev_MAC'], device['dev_LastIP'])
       
        if newName == -1 :
            notFound += 1
        elif newName == -2 :
            ignored += 1
        else :
            recordsToUpdate.append ([newName, device['dev_MAC']])
        # progress bar
        print ('.', end='')
        sys.stdout.flush()
            
    # Print log
    print ('')
    print ("        Names updated:  ", len(recordsToUpdate) )
    # DEBUG - print list of record to update
        # print (recordsToUpdate)

    # update devices
    sql.executemany ("UPDATE Devices SET dev_Name = ? WHERE dev_MAC = ? ", recordsToUpdate )

    # DEBUG - print number of rows updated
        # print (sql.rowcount)

#-------------------------------------------------------------------------------
def resolve_device_name (pMAC, pIP):
    try :
        pMACstr = str(pMAC)
        
        # Check MAC parameter
        mac = pMACstr.replace (':','')
        if len(pMACstr) != 17 or len(mac) != 12 :
            return -2

        # DEBUG
        # print (pMAC, pIP)

        # Resolve name with DIG
        dig_args = ['dig', '+short', '-x', pIP]
        newName = subprocess.check_output (dig_args, universal_newlines=True)

        # Check returns
        newName = newName.strip()
        if len(newName) == 0 :
            return -2
            
        # Eliminate local domain
        if newName.endswith('.') :
            newName = newName[:-1]
        if newName.endswith('.lan') :
            newName = newName[:-4]
        if newName.endswith('.local') :
            newName = newName[:-6]
        if newName.endswith('.home') :
            newName = newName[:-5]

        # Return newName
        return newName

    # not Found
    except subprocess.CalledProcessError :
        return -1            

#-------------------------------------------------------------------------------
def void_ghost_disconnections ():
    # Void connect ghost events (disconnect event exists in last X min.) 
    print_log ('Void - 1 Connect ghost events')
    sql.execute ("""UPDATE Events SET eve_PairEventRowid = Null,
                        eve_EventType ='VOIDED - ' || eve_EventType
                    WHERE eve_MAC != 'Internet'
                      AND eve_EventType = 'Connected'
                      AND eve_DateTime = ?
                      AND eve_MAC IN (
                          SELECT Events.eve_MAC
                          FROM CurrentScan, Devices, ScanCycles, Events 
                          WHERE cur_ScanCycle = ?
                            AND dev_MAC = cur_MAC
                            AND dev_ScanCycle = cic_ID
                            AND cic_ID = cur_ScanCycle
                            AND eve_MAC = cur_MAC
                            AND eve_EventType = 'Disconnected'
                            AND eve_DateTime >=
                                DATETIME (?, '-' || cic_EveryXmin ||' minutes')
                          ) """,
                    (startTime, cycle, startTime)   )

    # Void connect paired events
    print_log ('Void - 2 Paired events')
    sql.execute ("""UPDATE Events SET eve_PairEventRowid = Null 
                    WHERE eve_MAC != 'Internet'
                      AND eve_PairEventRowid IN (
                          SELECT Events.RowID
                          FROM CurrentScan, Devices, ScanCycles, Events 
                          WHERE cur_ScanCycle = ?
                            AND dev_MAC = cur_MAC
                            AND dev_ScanCycle = cic_ID
                            AND cic_ID = cur_ScanCycle
                            AND eve_MAC = cur_MAC
                            AND eve_EventType = 'Disconnected'
                            AND eve_DateTime >=
                                DATETIME (?, '-' || cic_EveryXmin ||' minutes')
                          ) """,
                    (cycle, startTime)   )

    # Void disconnect ghost events 
    print_log ('Void - 3 Disconnect ghost events')
    sql.execute ("""UPDATE Events SET eve_PairEventRowid = Null, 
                        eve_EventType = 'VOIDED - '|| eve_EventType
                    WHERE eve_MAC != 'Internet'
                      AND ROWID IN (
                          SELECT Events.RowID
                          FROM CurrentScan, Devices, ScanCycles, Events 
                          WHERE cur_ScanCycle = ?
                            AND dev_MAC = cur_MAC
                            AND dev_ScanCycle = cic_ID
                            AND cic_ID = cur_ScanCycle
                            AND eve_MAC = cur_MAC
                            AND eve_EventType = 'Disconnected'
                            AND eve_DateTime >=
                                DATETIME (?, '-' || cic_EveryXmin ||' minutes')
                          ) """,
                    (cycle, startTime)   )
    print_log ('Void end')

#-------------------------------------------------------------------------------
def pair_sessions_events ():
    # NOT NECESSARY FOR INCREMENTAL UPDATE
    # print_log ('Pair session - 1 Clean')
    # sql.execute ("""UPDATE Events
    #                 SET eve_PairEventRowid = NULL
    #                 WHERE eve_EventType IN ('New Device', 'Connected')
    #              """ )

    # Pair Connection / New Device events
    print_log ('Pair session - 1 Connections / New Devices')
    sql.execute ("""UPDATE Events
                    SET eve_PairEventRowid =
                       (SELECT ROWID
                        FROM Events AS EVE2
                        WHERE EVE2.eve_EventType IN ('New Device', 'Connected',
                            'Device Down', 'Disconnected')
                           AND EVE2.eve_MAC = Events.eve_MAC
                           AND EVE2.eve_Datetime > Events.eve_DateTime
                        ORDER BY EVE2.eve_DateTime ASC LIMIT 1)
                    WHERE eve_EventType IN ('New Device', 'Connected')
                    AND eve_PairEventRowid IS NULL
                 """ )

    # Pair Disconnection / Device Down
    print_log ('Pair session - 2 Disconnections')
    sql.execute ("""UPDATE Events
                    SET eve_PairEventRowid =
                        (SELECT ROWID
                         FROM Events AS EVE2
                         WHERE EVE2.eve_PairEventRowid = Events.ROWID)
                    WHERE eve_EventType IN ('Device Down', 'Disconnected')
                      AND eve_PairEventRowid IS NULL
                 """ )
    print_log ('Pair session end')

#-------------------------------------------------------------------------------
def create_sessions_snapshot ():
    # Clean sessions snapshot
    print_log ('Sessions Snapshot - 1 Clean')
    sql.execute ("DELETE FROM SESSIONS" )

    # Insert sessions
    print_log ('Sessions Snapshot - 2 Insert')
    sql.execute ("""INSERT INTO Sessions
                    SELECT * FROM Convert_Events_to_Sessions""" )

#    OLD FORMAT INSERT IN TWO PHASES
#    PERFORMACE BETTER THAN SELECT WITH UNION
#
#    # Insert sessions from first query
#    print_log ('Sessions Snapshot - 2 Query 1')
#    sql.execute ("""INSERT INTO Sessions
#                    SELECT * FROM Convert_Events_to_Sessions_Phase1""" )
#
#    # Insert sessions from first query
#    print_log ('Sessions Snapshot - 3 Query 2')
#    sql.execute ("""INSERT INTO Sessions
#                    SELECT * FROM Convert_Events_to_Sessions_Phase2""" )

    print_log ('Sessions end')

#-------------------------------------------------------------------------------
def skip_repeated_notifications ():
    # Skip repeated notifications
    # due strfime : Overflow --> use  "strftime / 60"
    print_log ('Skip Repeated')
    sql.execute ("""UPDATE Events SET eve_PendingAlertEmail = 0
                    WHERE eve_PendingAlertEmail = 1 AND eve_MAC IN
                        (
                        SELECT dev_MAC FROM Devices
                        WHERE dev_LastNotification IS NOT NULL
                          AND dev_LastNotification <>""
                          AND (strftime("%s", dev_LastNotification)/60 +
                                dev_SkipRepeated * 60) >
                              (strftime('%s','now','localtime')/60 )
                        )
                 """ )
    print_log ('Skip Repeated end')


#===============================================================================
# REPORTING
#===============================================================================
def email_reporting ():
    global mail_text
    global mail_html
    
    # Reporting section
    print ('\nReporting...')
    openDB()

    # Open text Template
    template_file = open(PIALERT_BACK_PATH + '/report_template.txt', 'r') 
    mail_text = template_file.read() 
    template_file.close() 

    # Open html Template
    template_file = open(PIALERT_BACK_PATH + '/report_template.html', 'r') 
    mail_html = template_file.read() 
    template_file.close() 

    # Report Header & footer
    timeFormated = startTime.strftime ('%Y-%m-%d %H:%M')
    mail_text = mail_text.replace ('<REPORT_DATE>', timeFormated)
    mail_html = mail_html.replace ('<REPORT_DATE>', timeFormated)

    mail_text = mail_text.replace ('<SCAN_CYCLE>', cycle )
    mail_html = mail_html.replace ('<SCAN_CYCLE>', cycle )

    mail_text = mail_text.replace ('<SERVER_NAME>', socket.gethostname() )
    mail_html = mail_html.replace ('<SERVER_NAME>', socket.gethostname() )
    
    mail_text = mail_text.replace ('<PIALERT_VERSION>', VERSION )
    mail_html = mail_html.replace ('<PIALERT_VERSION>', VERSION )

    mail_text = mail_text.replace ('<PIALERT_VERSION_DATE>', VERSION_DATE )
    mail_html = mail_html.replace ('<PIALERT_VERSION_DATE>', VERSION_DATE )

    mail_text = mail_text.replace ('<PIALERT_YEAR>', VERSION_YEAR )
    mail_html = mail_html.replace ('<PIALERT_YEAR>', VERSION_YEAR )

    # Compose Internet Section
    print ('    Formating report...')
    mail_section_Internet = False
    mail_text_Internet = ''
    mail_html_Internet = ''
    text_line_template = '    {} \t{}\t{}\t{}\n'
    html_line_template = '<tr>\n'+ \
        '  <td> <a href="{}{}"> {} </a> </td>\n  <td> {} </td>\n'+ \
        '  <td style="font-size: 24px; color:#D02020"> {} </td>\n'+ \
        '  <td> {} </td>\n</tr>\n'

    sql.execute ("""SELECT * FROM Events
                    WHERE eve_PendingAlertEmail = 1 AND eve_MAC = 'Internet'
                    ORDER BY eve_DateTime""")

    for eventAlert in sql :
        mail_section_Internet = True
        mail_text_Internet += text_line_template.format (
            eventAlert['eve_EventType'], eventAlert['eve_DateTime'],
            eventAlert['eve_IP'], eventAlert['eve_AdditionalInfo'])
        mail_html_Internet += html_line_template.format (
            REPORT_DEVICE_URL, eventAlert['eve_MAC'],
            eventAlert['eve_EventType'], eventAlert['eve_DateTime'],
            eventAlert['eve_IP'], eventAlert['eve_AdditionalInfo'])

    format_report_section (mail_section_Internet, 'SECTION_INTERNET',
        'TABLE_INTERNET', mail_text_Internet, mail_html_Internet)

    # Compose New Devices Section
    mail_section_new_devices = False
    mail_text_new_devices = ''
    mail_html_new_devices = ''
    text_line_template    = '    {}\t{}\t{}\t{}\t{}\n'
    html_line_template    = '<tr>\n'+ \
        '  <td> <a href="{}{}"> {} </a> </td>\n  <td> {} </td>\n'+\
        '  <td> {} </td>\n  <td> {} </td>\n  <td> {} </td>\n</tr>\n'
    
    sql.execute ("""SELECT * FROM Events_Devices
                    WHERE eve_PendingAlertEmail = 1
                      AND eve_EventType = 'New Device'
                    ORDER BY eve_DateTime""")

    for eventAlert in sql :
        mail_section_new_devices = True
        mail_text_new_devices += text_line_template.format (
            eventAlert['eve_MAC'], eventAlert['eve_DateTime'],
            eventAlert['eve_IP'], eventAlert['dev_Name'],
            eventAlert['eve_AdditionalInfo'])
        mail_html_new_devices += html_line_template.format (
            REPORT_DEVICE_URL, eventAlert['eve_MAC'], eventAlert['eve_MAC'],
            eventAlert['eve_DateTime'], eventAlert['eve_IP'],
            eventAlert['dev_Name'], eventAlert['eve_AdditionalInfo'])

    format_report_section (mail_section_new_devices, 'SECTION_NEW_DEVICES',
        'TABLE_NEW_DEVICES', mail_text_new_devices, mail_html_new_devices)

    # Compose Devices Down Section
    mail_section_devices_down = False
    mail_text_devices_down = ''
    mail_html_devices_down = ''
    text_line_template     = '    {}\t{}\t{}\t{}\n'
    html_line_template     = '<tr>\n'+ \
        '  <td> <a href="{}{}"> {} </a>  </td>\n  <td> {} </td>\n'+ \
        '  <td> {} </td>\n  <td> {} </td>\n</tr>\n'

    sql.execute ("""SELECT * FROM Events_Devices
                    WHERE eve_PendingAlertEmail = 1
                      AND eve_EventType = 'Device Down'
                    ORDER BY eve_DateTime""")

    for eventAlert in sql :
        mail_section_devices_down = True
        mail_text_devices_down += text_line_template.format (
            eventAlert['eve_MAC'], eventAlert['eve_DateTime'],
            eventAlert['eve_IP'], eventAlert['dev_Name'])
        mail_html_devices_down += html_line_template.format (
            REPORT_DEVICE_URL, eventAlert['eve_MAC'], eventAlert['eve_MAC'],
            eventAlert['eve_DateTime'], eventAlert['eve_IP'],
            eventAlert['dev_Name'])

    format_report_section (mail_section_devices_down, 'SECTION_DEVICES_DOWN',
        'TABLE_DEVICES_DOWN', mail_text_devices_down, mail_html_devices_down)

    # Compose Events Section
    mail_section_events = False
    mail_text_events   = ''
    mail_html_events   = ''
    text_line_template = '    {}\t{}\t{}\t{}\t{}\t{}\n'
    html_line_template = '<tr>\n  <td>'+ \
            ' <a href="{}{}"> {} </a> </td>\n  <td> {} </td>\n'+ \
            '  <td> {} </td>\n  <td> {} </td>\n  <td> {} </td>\n'+ \
            '  <td> {} </td>\n</tr>\n'

    sql.execute ("""SELECT * FROM Events_Devices
                    WHERE eve_PendingAlertEmail = 1
                      AND eve_EventType IN ('Connected','Disconnected',
                          'IP Changed')
                    ORDER BY eve_DateTime""")

    for eventAlert in sql :
        mail_section_events = True
        mail_text_events += text_line_template.format (
            eventAlert['eve_MAC'], eventAlert['eve_DateTime'],
            eventAlert['eve_IP'], eventAlert['eve_EventType'],
            eventAlert['dev_Name'], eventAlert['eve_AdditionalInfo'])
        mail_html_events += html_line_template.format (
            REPORT_DEVICE_URL, eventAlert['eve_MAC'], eventAlert['eve_MAC'],
            eventAlert['eve_DateTime'], eventAlert['eve_IP'],
            eventAlert['eve_EventType'], eventAlert['dev_Name'],
            eventAlert['eve_AdditionalInfo'])

    format_report_section (mail_section_events, 'SECTION_EVENTS',
        'TABLE_EVENTS', mail_text_events, mail_html_events)

    # DEBUG - Write output emails for testing
    if True :
        write_file (LOG_PATH + '/report_output.txt', mail_text) 
        write_file (LOG_PATH + '/report_output.html', mail_html) 

    # Send Mail
    if mail_section_Internet == True or mail_section_new_devices == True \
    or mail_section_devices_down == True or mail_section_events == True :
        if REPORT_MAIL :
            print ('    Sending report by email...')
            send_email (mail_text, mail_html)
        else :
            print ('    Skip mail...')
    else :
        print ('    No changes to report...')
    

    # Clean Pending Alert Events
    sql.execute ("""UPDATE Devices SET dev_LastNotification = ?
                    WHERE dev_MAC IN (SELECT eve_MAC FROM Events
                                      WHERE eve_PendingAlertEmail = 1)
                 """, (datetime.datetime.now(),) )
    sql.execute ("""UPDATE Events SET eve_PendingAlertEmail = 0
                    WHERE eve_PendingAlertEmail = 1""")

    # DEBUG - print number of rows updated
    print ('    Notifications:', sql.rowcount)

    # Commit changes
    sql_connection.commit()
    closeDB()

#-------------------------------------------------------------------------------
def format_report_section (pActive, pSection, pTable, pText, pHTML):
    global mail_text
    global mail_html

    # Replace section text
    if pActive :
        mail_text = mail_text.replace ('<'+ pTable +'>', pText)
        mail_html = mail_html.replace ('<'+ pTable +'>', pHTML)       

        mail_text = remove_tag (mail_text, pSection)       
        mail_html = remove_tag (mail_html, pSection)
    else:
        mail_text = remove_section (mail_text, pSection)
        mail_html = remove_section (mail_html, pSection)

#-------------------------------------------------------------------------------
def remove_section (pText, pSection):
    # Search section into the text
    if pText.find ('<'+ pSection +'>') >=0 \
    and pText.find ('</'+ pSection +'>') >=0 : 
        # return text without the section
        return pText[:pText.find ('<'+ pSection+'>')] + \
               pText[pText.find ('</'+ pSection +'>') + len (pSection) +3:]
    else :
        # return all text
        return pText

#-------------------------------------------------------------------------------
def remove_tag (pText, pTag):
    # return text without the tag
    return pText.replace ('<'+ pTag +'>','').replace ('</'+ pTag +'>','')

#-------------------------------------------------------------------------------
def write_file (pPath, pText):
    # Write the text depending using the correct python version
    if sys.version_info < (3, 0):
        file = io.open (pPath , mode='w', encoding='utf-8')
        file.write ( pText.decode('unicode_escape') ) 
        file.close() 
    else:
        file = open (pPath, 'w', encoding='utf-8') 
        file.write (pText) 
        file.close() 

#-------------------------------------------------------------------------------
def append_line_to_file (pPath, pText):
    # append the line depending using the correct python version
    if sys.version_info < (3, 0):
        file = io.open (pPath , mode='a', encoding='utf-8')
        file.write ( pText.decode('unicode_escape') ) 
        file.close() 
    else:
        file = open (pPath, 'a', encoding='utf-8') 
        file.write (pText) 
        file.close() 

#-------------------------------------------------------------------------------
def send_email (pText, pHTML):
    # Compose email
    msg = MIMEMultipart('alternative')
    msg['Subject'] = 'Pi.Alert Report'
    msg['From'] = REPORT_FROM
    msg['To'] = REPORT_TO
    msg.attach (MIMEText (pText, 'plain'))
    msg.attach (MIMEText (pHTML, 'html'))

    # Send mail
    smtp_connection = smtplib.SMTP (SMTP_SERVER, SMTP_PORT)
    smtp_connection.ehlo()
    smtp_connection.starttls()
    smtp_connection.ehlo()
    smtp_connection.login (SMTP_USER, SMTP_PASS)
    smtp_connection.sendmail (REPORT_FROM, REPORT_TO, msg.as_string())
    smtp_connection.quit()


#===============================================================================
# DB
#===============================================================================
def openDB ():
    global sql_connection
    global sql

    # Check if DB is open
    if sql_connection != None :
        return

    # Log    
    print_log ('Opening DB...')

    # Open DB and Cursor
    sql_connection = sqlite3.connect (DB_PATH, isolation_level=None)
    sql_connection.text_factory = str
    sql_connection.row_factory = sqlite3.Row
    sql = sql_connection.cursor()

#-------------------------------------------------------------------------------
def closeDB ():
    global sql_connection
    global sql

    # Check if DB is open
    if sql_connection == None :
        return

    # Log    
    print_log ('Closing DB...')

    # Close DB
    sql_connection.commit()
    sql_connection.close()
    sql_connection = None    


#===============================================================================
# UTIL
#===============================================================================
def print_log (pText):
    global log_timestamp

    # Check LOG actived
    if not PRINT_LOG :
        return

    # Current Time    
    log_timestamp2 = datetime.datetime.now()

    # Print line + time + elapsed time + text
    print ('--------------------> ',
        log_timestamp2, ' ',
        log_timestamp2 - log_timestamp, ' ',
        pText)

    # Save current time to calculate elapsed time until next log
    log_timestamp = log_timestamp2


#===============================================================================
# BEGIN
#===============================================================================
if __name__ == '__main__':
    sys.exit(main())       