#!/usr/bin/env python3
"""
DKIM Record Checker - Email Signature Validator
Validates DKIM records for email authentication
"""
import dns.resolver
import re

def check_dkim_record(domain, selector='default'):
    """Check DKIM record for a domain and selector"""
    try:
        dkim_domain = f'{selector}._domainkey.{domain}'
        txt_records = dns.resolver.resolve(dkim_domain, 'TXT')

        for record in txt_records:
            txt = ''.join([s.decode() if isinstance(s, bytes)
                          else s for s in record.strings])
            if 'v=DKIM1' in txt or 'p=' in txt:
                # Parse DKIM record
                version = re.search(r'v=([^;]+)', txt)
                key_type = re.search(r'k=([^;]+)', txt)
                public_key = re.search(r'p=([^;]+)', txt)

                return {
                    'domain': domain,
                    'selector': selector,
                    'status': 'VALID',
                    'dkim_record': txt,
                    'version': version.group(1) if version else 'DKIM1',
                    'key_type': key_type.group(1) if key_type else 'rsa',
                    'has_public_key': bool(public_key and public_key.group(1))
                }

        return {'domain': domain, 'selector': selector,
                'status': 'INVALID', 'error': 'No DKIM record found'}
    except dns.resolver.NXDOMAIN:
        return {'domain': domain, 'selector': selector,
                'status': 'MISSING', 'error': 'DKIM record not found'}
    except Exception as e:
        return {'domain': domain, 'selector': selector,
                'status': 'ERROR', 'error': str(e)}

# Common selectors to check
COMMON_SELECTORS = ['default', 'selector1', 'selector2',
                    'google', 'k1', 's1', 's2', 'mail']

if __name__ == '__main__':
    domain = input('Enter domain: ')
    for selector in COMMON_SELECTORS:
        result = check_dkim_record(domain, selector)
        if result['status'] == 'VALID':
            print(f"Found: {selector}._domainkey.{domain}")
            print(f"Key Type: {result['key_type']}")
            break