#!/usr/bin/env python
# ICANN API for the Centralized Zones Data Service - developed by acidvegas (https://git.acid.vegas/czds)
# Reference: https://czds.icann.org

import argparse
import concurrent.futures
import getpass
import logging
import os

try:
	import requests
except ImportError:
	raise ImportError('Missing dependency: requests (pip install requests)')


# Setting up logging
logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(name)s - %(levelname)s - %(message)s')


def authenticate(username: str, password: str) -> str:
	'''
	Authenticate with ICANN's API and return the access token.

	:param username: ICANN Username
	:param password: ICANN Password
	'''

	response = requests.post('https://account-api.icann.org/api/authenticate', json={'username': username, 'password': password})
	response.raise_for_status()

	return response.json()['accessToken']


def download_zone(url: str, token: str, output_directory: str):
	'''
	Download a single zone file.

	:param url: URL to download
	:param token: ICANN access token
	:param output_directory: Directory to save the zone file
	'''

	headers = {'Authorization': f'Bearer {token}'}
	response = requests.get(url, headers=headers)
	response.raise_for_status()
	filename = response.headers.get('Content-Disposition').split('filename=')[-1].strip('"')
	filepath = os.path.join(output_directory, filename)

	with open(filepath, 'wb') as file:
		for chunk in response.iter_content(chunk_size=1024):
			file.write(chunk)
	return filepath


def main(username: str, password: str, concurrency: int):
	'''
	Main function to download all zone files.

	:param username: ICANN Username
	:param password: ICANN Password
	:param concurrency: Number of concurrent downloads
	'''

	token = authenticate(username, password)
	headers = {'Authorization': f'Bearer {token}'}
	response = requests.get('https://czds-api.icann.org/czds/downloads/links', headers=headers)
	response.raise_for_status()
	zone_links = response.json()
	output_directory = 'zonefiles'

	os.makedirs(output_directory, exist_ok=True)

	with concurrent.futures.ThreadPoolExecutor(max_workers=concurrency) as executor:

		future_to_url = {executor.submit(download_zone, url, token, output_directory): url for url in zone_links}

		for future in concurrent.futures.as_completed(future_to_url):

			url = future_to_url[future]

			try:
				filepath = future.result()
				logging.info(f'Completed downloading {url} to file {filepath}')
			except Exception as e:
				logging.error(f'{url} generated an exception: {e}')



if __name__ == '__main__':
	parser = argparse.ArgumentParser(description="ICANN Zone Files Downloader")
	parser.add_argument('-u', '--username', help='ICANN Username')
	parser.add_argument('-p', '--password', help='ICANN Password')
	parser.add_argument('-c', '--concurrency', type=int, default=5, help='Number of concurrent downloads')
	args = parser.parse_args()

	username = args.username or os.getenv('CZDS_USER')
	password = args.password or os.getenv('CZDS_PASS')

	if not username:
		username = input('ICANN Username: ')

	if not password:
		password = getpass.getpass('ICANN Password: ')

	try:
		main(username, password, args.concurrency)
	except requests.HTTPError as e:
		logging.error(f'HTTP error occurred: {e.response.status_code} - {e.response.reason}')
	except Exception as e:
		logging.error(f'An error occurred: {e}')