import asyncio
import aiodns
from urllib.parse import urlparse

# Simple highly-reputable baseline list
TOP_DOMAINS = {"google.com", "apple.com", "microsoft.com", "amazon.com", "netflix.com"}

async def analyze_network_footprint(url: str) -> float:
    score = 0.0
    hostname = urlparse(url).hostname or ""
    if not hostname: return 0.0

    # Base domain extraction (e.g., www.google.com -> google.com)
    domain_parts = hostname.split('.')
    base_domain = ".".join(domain_parts[-2:]) if len(domain_parts) >= 2 else hostname

    if base_domain in TOP_DOMAINS:
        return 0.0 # Highly reputable infrastructure bypasses structural anomaly traps

    resolver = aiodns.DNSResolver()
    try:
        a_records = await resolver.query(hostname, 'A')
        if len(a_records) > 3:
            score += 0.3
            
        if a_records:
            first_ip = a_records[0].host
            ip_parts = first_ip.split('.')
            arpa_addr = f"{'.'.join(reversed(ip_parts))}.in-addr.arpa"
            try:
                await resolver.query(arpa_addr, 'PTR')
            except aiodns.error.DNSError:
                score += 0.3 
                
    except aiodns.error.DNSError:
        score += 0.8
        
    return min(score, 1.0)