import whois
import logging
import sys
import time
from typing import Optional, List


def setup_logging():
    logging.basicConfig(
        level=logging.INFO,
        format="%(asctime)s [%(levelname)s] %(message)s",
        handlers=[
            logging.StreamHandler(sys.stdout)
        ]
    )


def check_domain_availability(domain: str) -> Optional[bool]:
    try:
        w = whois.whois(domain)
        if w.status is None:
            logging.info(f"{domain} is available.")
            return True
        else:
            logging.info(f"{domain} is not available.")
            return False
    except Exception as e:
        logging.error(f"An error occurred while checking {domain}: {e}")
        return None


def read_domains_from_file(file_path: str) -> List[str]:
    try:
        with open(file_path, "r") as f:
            domains = [line.strip() for line in f.readlines() if line.strip()]
        return domains
    except FileNotFoundError:
        logging.error(f"File not found: {file_path}")
        return []
    except Exception as e:
        logging.error(f"An error occurred while reading domains from the file: {e}")
        return []


def write_available_domains_to_file(available_domains: List[str], output_file: str):
    try:
        with open(output_file, "w") as f:
            for domain in available_domains:
                f.write(f"{domain}\n")
        logging.info(f"Available domains saved to {output_file}")
    except Exception as e:
        logging.error(f"An error occurred while writing available domains to the file: {e}")


if __name__ == "__main__":
    setup_logging()

    if len(sys.argv) != 2:
        logging.error("Usage: python domain_checker.py [path_to_domains_file]")
        sys.exit(1)

    input_file = sys.argv[1]
    output_file = "available_domains.txt"

    domains = read_domains_from_file(input_file)
    available_domains = []

    delay_seconds = 5  # Set the delay between domain checks (in seconds)

    for domain in domains:
        is_available = check_domain_availability(domain)
        if is_available is True:
            available_domains.append(domain)
        time.sleep(delay_seconds)

    write_available_domains_to_file(available_domains, output_file)