#!/usr/bin/env python

import os
import sys
import subprocess

# Define the installation path and extend the system path for plugin imports
INSTALL_PATH = os.getenv('NETALERTX_APP', '/app')
sys.path.extend([f"{INSTALL_PATH}/front/plugins", f"{INSTALL_PATH}/server"])

from plugin_helper import Plugin_Objects
from logger import mylog, Logger
from const import logPath
from helper import get_setting_value 
from database import DB
from models.device_instance import DeviceInstance
import conf
from pytz import timezone

# Make sure the TIMEZONE for logging is correct
conf.tz = timezone(get_setting_value('TIMEZONE'))

# Make sure log level is initialized correctly
Logger(get_setting_value('LOG_LEVEL'))

pluginName = 'DIGSCAN'

# Define the current path and log file paths
LOG_PATH = logPath + '/plugins'
LOG_FILE = os.path.join(LOG_PATH, f'script.{pluginName}.log')
RESULT_FILE = os.path.join(LOG_PATH, f'last_result.{pluginName}.log')

# Initialize the Plugin obj output file
plugin_objects = Plugin_Objects(RESULT_FILE)


def main():
    mylog('verbose', [f'[{pluginName}] In script']) 

    timeout = get_setting_value('DIGSCAN_RUN_TIMEOUT')

    # Create a database connection
    db = DB()  # instance of class DB
    db.open()

    # Initialize the Plugin obj output file
    plugin_objects = Plugin_Objects(RESULT_FILE)

    # Create a DeviceInstance instance
    device_handler = DeviceInstance(db)

    # Retrieve devices
    if get_setting_value("REFRESH_FQDN"): 
        devices = device_handler.getAll()
    else:        
        devices = device_handler.getUnknown()

    mylog('verbose', [f'[{pluginName}] Devices count: {len(devices)}'])   
    
    # TEST - below is a WINDOWS host IP
    # execute_name_lookup('192.168.1.121', timeout)

    for device in devices:
        domain_name, dns_server = execute_name_lookup(device['devLastIP'], timeout)

        if domain_name != '':
            plugin_objects.add_object(
            # "MAC", "IP", "Server", "Name"
            primaryId   = device['devMac'],
            secondaryId = device['devLastIP'],
            watched1    = dns_server,
            watched2    = domain_name,
            watched3    = '',
            watched4    = '',
            extra       = '',
            foreignKey  = device['devMac'])

    plugin_objects.write_result_file()
    
    
    mylog('verbose', [f'[{pluginName}] Script finished'])   
    
    return 0

#===============================================================================
# Execute scan
#===============================================================================
def execute_name_lookup (ip, timeout):
    """
    Execute the DIG command on IP.
    """

    args = ['dig', '+short', '-x', ip]

    # Execute command
    output = ""

    try:
        mylog('verbose', [f'[{pluginName}] DEBUG CMD :', args])
        
        # try runnning a subprocess with a forced (timeout)  in case the subprocess hangs
        output = subprocess.check_output (args, universal_newlines=True,  stderr=subprocess.STDOUT, timeout=(timeout), text=True).strip()

        mylog('verbose', [f'[{pluginName}] DEBUG OUTPUT : {output}'])

        domain_name = output
        dns_server = ''      

        mylog('verbose', [f'[{pluginName}] Domain Name: {domain_name}'])

        return domain_name, dns_server

    except subprocess.CalledProcessError as e:
        mylog('verbose', [f'[{pluginName}] ⚠ ERROR - {e.output}'])                    
        
    except subprocess.TimeoutExpired:
        mylog('verbose', [f'[{pluginName}] TIMEOUT - the process forcefully terminated as timeout reached']) 

    if output == "": # check if the subprocess failed                 
        mylog('verbose', [f'[{pluginName}] Scan: FAIL - check logs']) 
    else: 
        mylog('verbose', [f'[{pluginName}] Scan: SUCCESS'])

    return '', ''   

if __name__ == '__main__':
    main()