pounce/backend/app/services/drop_status_checker.py

"""
Drop Status Checker
====================
Dedicated RDAP checker for dropped domains.
Correctly identifies pending_delete, redemption, and available status.
Extracts deletion date for countdown display.
"""

import asyncio
import httpx
import logging
from dataclasses import dataclass
from datetime import datetime
from typing import Optional

logger = logging.getLogger(__name__)

# RDAP endpoints for different TLDs
RDAP_ENDPOINTS = {
    # ccTLDs
    'ch': 'https://rdap.nic.ch/domain/',
    'li': 'https://rdap.nic.ch/domain/',
    'de': 'https://rdap.denic.de/domain/',
    # gTLDs via CentralNic
    'online': 'https://rdap.centralnic.com/online/domain/',
    'xyz': 'https://rdap.centralnic.com/xyz/domain/',
    'club': 'https://rdap.nic.club/domain/',
    # gTLDs via Afilias/Donuts
    'info': 'https://rdap.afilias.net/rdap/info/domain/',
    'biz': 'https://rdap.afilias.net/rdap/biz/domain/',
    'org': 'https://rdap.publicinterestregistry.org/rdap/org/domain/',
    # Google TLDs
    'dev': 'https://rdap.nic.google/domain/',
    'app': 'https://rdap.nic.google/domain/',
}


@dataclass
class DropStatus:
    """Status of a dropped domain."""
    domain: str
    status: str  # 'available', 'dropping_soon', 'taken', 'unknown'
    rdap_status: list[str]
    can_register_now: bool
    should_monitor: bool
    message: str
    deletion_date: Optional[datetime] = None  # When domain will be fully deleted


async def check_drop_status(domain: str) -> DropStatus:
    """
    Check the real status of a dropped domain via RDAP.
    
    Returns:
        DropStatus with one of:
        - 'available': Domain can be registered NOW
        - 'dropping_soon': Domain is in pending delete/redemption (monitor it!)
        - 'taken': Domain was re-registered
        - 'unknown': Could not determine status
    """
    tld = domain.split('.')[-1].lower()
    
    endpoint = RDAP_ENDPOINTS.get(tld)
    if not endpoint:
        # Try generic lookup
        logger.warning(f"No RDAP endpoint for .{tld}, returning unknown")
        return DropStatus(
            domain=domain,
            status='unknown',
            rdap_status=[],
            can_register_now=False,
            should_monitor=False,
            message=f"No RDAP endpoint for .{tld}"
        )
    
    url = f"{endpoint}{domain}"
    
    try:
        async with httpx.AsyncClient(timeout=10) as client:
            resp = await client.get(url)
            
            # 404 = Domain not found = AVAILABLE!
            if resp.status_code == 404:
                return DropStatus(
                    domain=domain,
                    status='available',
                    rdap_status=[],
                    can_register_now=True,
                    should_monitor=False,
                    message="Domain is available for registration!"
                )
            
            # 200 = Domain exists in registry
            if resp.status_code == 200:
                data = resp.json()
                rdap_status = data.get('status', [])
                status_lower = ' '.join(str(s).lower() for s in rdap_status)
                
                # Extract deletion date from events
                deletion_date = None
                events = data.get('events', [])
                for event in events:
                    action = event.get('eventAction', '').lower()
                    date_str = event.get('eventDate', '')
                    if action in ('deletion', 'expiration') and date_str:
                        try:
                            # Parse ISO date
                            deletion_date = datetime.fromisoformat(date_str.replace('Z', '+00:00'))
                        except (ValueError, TypeError):
                            pass
                
                # Check for pending delete / redemption status
                is_pending = any(x in status_lower for x in [
                    'pending delete', 'pendingdelete',
                    'pending purge', 'pendingpurge',
                    'redemption period', 'redemptionperiod',
                    'pending restore', 'pendingrestore',
                ])
                
                if is_pending:
                    return DropStatus(
                        domain=domain,
                        status='dropping_soon',
                        rdap_status=rdap_status,
                        can_register_now=False,
                        should_monitor=True,
                        message="Domain is being deleted. Track it to get notified when available!",
                        deletion_date=deletion_date,
                    )
                
                # Domain is actively registered
                return DropStatus(
                    domain=domain,
                    status='taken',
                    rdap_status=rdap_status,
                    can_register_now=False,
                    should_monitor=False,
                    message="Domain was re-registered",
                    deletion_date=None,
                )
            
            # Other status code
            logger.warning(f"RDAP returned {resp.status_code} for {domain}")
            return DropStatus(
                domain=domain,
                status='unknown',
                rdap_status=[],
                can_register_now=False,
                should_monitor=False,
                message=f"RDAP returned HTTP {resp.status_code}"
            )
            
    except httpx.TimeoutException:
        logger.warning(f"RDAP timeout for {domain}")
        return DropStatus(
            domain=domain,
            status='unknown',
            rdap_status=[],
            can_register_now=False,
            should_monitor=False,
            message="RDAP timeout"
        )
    except Exception as e:
        logger.warning(f"RDAP error for {domain}: {e}")
        return DropStatus(
            domain=domain,
            status='unknown',
            rdap_status=[],
            can_register_now=False,
            should_monitor=False,
            message=str(e)
        )


# Rate limiting: max requests per second per TLD
RATE_LIMITS = {
    'default': 5,  # 5 requests per second
    'ch': 10,      # Swiss registry is faster
    'li': 10,
}


async def check_drops_batch(
    domains: list[tuple[int, str]],  # List of (id, full_domain)
    delay_between_requests: float = 0.2,  # 200ms = 5 req/s
) -> list[tuple[int, DropStatus]]:
    """
    Check multiple drops with rate limiting.
    
    Args:
        domains: List of (drop_id, full_domain) tuples
        delay_between_requests: Seconds to wait between requests (default 200ms)
    
    Returns:
        List of (drop_id, DropStatus) tuples
    """
    results = []
    
    for drop_id, domain in domains:
        try:
            status = await check_drop_status(domain)
            results.append((drop_id, status))
        except Exception as e:
            logger.error(f"Batch check failed for {domain}: {e}")
            results.append((drop_id, DropStatus(
                domain=domain,
                status='unknown',
                rdap_status=[],
                can_register_now=False,
                should_monitor=False,
                message=str(e),
            )))
        
        # Rate limit
        await asyncio.sleep(delay_between_requests)
    
    return results