import subprocess
import time
import datetime
import re

def establish_vpn_connection(ovpn_file, credential_file, log_file):
    """
    Establishes a VPN connection using the provided OVPN file and credentials.
    Returns True if the connection is successful, False otherwise.
    """

    # Read credentials
    with open(credential_file, 'r') as f:
        username = f.readline().strip()
        password = f.readline().strip()

    # Establish VPN connection (capture stdout and stderr)
    openvpn_command = ["openvpn", "--config", ovpn_file, 
                       "--auth-user-pass", credential_file, "--daemon", 
                       "--log-append", log_file, "--verb", "3"]

    process = subprocess.Popen(openvpn_command, 
                                stdin=subprocess.PIPE, 
                                stdout=subprocess.PIPE, 
                                stderr=subprocess.PIPE)
    stdout, stderr = process.communicate(input=password.encode())

    # Check for errors
    if process.returncode != 0:
        return False, stderr.decode()
    else:
        return True, stdout.decode()

def is_vpn_active(ovpn_filename):
    """
    Checks if the VPN connection associated with the given OVPN filename is active.
    Returns True if active, False otherwise.
    """
    try:
        subprocess.run(["pgrep", "-f", ovpn_filename], check=True, capture_output=True)
        return True
    except subprocess.CalledProcessError:
        return False

def disconnect_vpn():
    """
    Disconnects the active VPN connection.
    """
    try:
        result = subprocess.run(["pgrep", "openvpn"], check=True, capture_output=True)
        pids = result.stdout.decode().strip().split('\n')
        for pid in pids:
            subprocess.run(["kill", pid])
    except subprocess.CalledProcessError:
        pass  # No openvpn process found

def get_external_ip():
    """
    Gets the external IP address using various services, with retries.
    Returns the external IP if successful, or None if unable to get it.
    """

    for service in ["ifconfig.me", "ifconfig.co", "ipinfo.io/ip"]:
        try:
            external_ip = subprocess.check_output(["curl", "-s", service]).decode().strip()
            if re.match(r"^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$", external_ip):
                return external_ip
            else:
                print(f"{datetime.datetime.now()} [Main Script]: Invalid response from {service}")
        except subprocess.CalledProcessError:
            print(f"{datetime.datetime.now()} [Main Script]: Error getting external IP from {service}")
    
    return None  # Unable to get external IP