cosmo/backend/app/services/nasa_sbdb_service.py

"""
NASA SBDB (Small-Body Database) Close-Approach Data API Service
Fetches close approach events for asteroids and comets
API Docs: https://ssd-api.jpl.nasa.gov/doc/cad.html
"""
import logging
import httpx
from typing import List, Dict, Optional, Any
from datetime import datetime, timedelta
from app.config import settings

logger = logging.getLogger(__name__)


class NasaSbdbService:
    """NASA Small-Body Database Close-Approach Data API client"""

    def __init__(self):
        self.base_url = "https://ssd-api.jpl.nasa.gov/cad.api"
        self.timeout = settings.nasa_api_timeout or 30

    async def get_close_approaches(
        self,
        date_min: Optional[str] = None,
        date_max: Optional[str] = None,
        dist_max: Optional[str] = "0.2",  # Max distance in AU (Earth-Moon distance ~0.0026 AU)
        body: Optional[str] = None,
        sort: str = "date",
        limit: Optional[int] = None,
        fullname: bool = False
    ) -> List[Dict[str, Any]]:
        """
        Query NASA SBDB Close-Approach Data API

        Args:
            date_min: Minimum approach date (YYYY-MM-DD or 'now')
            date_max: Maximum approach date (YYYY-MM-DD)
            dist_max: Maximum approach distance in AU (default 0.2 AU)
            body: Filter by specific body (e.g., 'Earth')
            sort: Sort by 'date', 'dist', 'dist-min', etc.
            limit: Maximum number of results
            fullname: Return full designation names

        Returns:
            List of close approach events
        """
        params = {
            "dist-max": dist_max,
            "sort": sort,
            "fullname": "true" if fullname else "false"
        }

        if date_min:
            params["date-min"] = date_min
        if date_max:
            params["date-max"] = date_max
        if body:
            params["body"] = body
        if limit:
            params["limit"] = str(limit)

        logger.info(f"Querying NASA SBDB for close approaches: {params}")

        # Use proxy if configured
        proxies = settings.proxy_dict
        if proxies:
            logger.info(f"Using proxy for NASA SBDB API")

        try:
            async with httpx.AsyncClient(timeout=self.timeout, proxies=proxies) as client:
                response = await client.get(self.base_url, params=params)
                response.raise_for_status()

                data = response.json()

                if "data" not in data:
                    logger.warning("No data field in NASA SBDB response")
                    return []

                # Parse response
                fields = data.get("fields", [])
                rows = data.get("data", [])

                events = []
                for row in rows:
                    event = dict(zip(fields, row))
                    events.append(event)

                logger.info(f"Retrieved {len(events)} close approach events from NASA SBDB")
                return events

        except httpx.HTTPStatusError as e:
            logger.error(f"NASA SBDB API HTTP error: {e.response.status_code} - {e.response.text}")
            return []
        except httpx.TimeoutException:
            logger.error(f"NASA SBDB API timeout after {self.timeout}s")
            return []
        except Exception as e:
            logger.error(f"Error querying NASA SBDB: {e}")
            return []

    def parse_event_to_celestial_event(self, sbdb_event: Dict[str, Any], approach_body: str = "Earth") -> Dict[str, Any]:
        """
        Parse NASA SBDB event data to CelestialEvent format

        Args:
            sbdb_event: Event data from NASA SBDB API
            approach_body: Name of the body being approached (e.g., "Earth", "Mars")

        SBDB fields typically include:
        - des: Object designation
        - orbit_id: Orbit ID
        - jd: Julian Date of close approach
        - cd: Calendar date (YYYY-MMM-DD HH:MM)
        - dist: Nominal approach distance (AU)
        - dist_min: Minimum approach distance (AU)
        - dist_max: Maximum approach distance (AU)
        - v_rel: Relative velocity (km/s)
        - v_inf: Velocity at infinity (km/s)
        - t_sigma_f: Time uncertainty (formatted string)
        - h: Absolute magnitude
        - fullname: Full object name (if requested)
        """
        try:
            # Extract fields
            designation = sbdb_event.get("des", "Unknown")
            fullname = sbdb_event.get("fullname", designation)
            cd = sbdb_event.get("cd", "")  # Calendar date string
            dist = sbdb_event.get("dist", "")  # Nominal distance in AU
            dist_min = sbdb_event.get("dist_min", "")
            v_rel = sbdb_event.get("v_rel", "")
            # Note: NASA API doesn't return the approach body, so we use the parameter
            body = approach_body

            # Parse date (format: YYYY-MMM-DD HH:MM)
            event_time = datetime.strptime(cd, "%Y-%b-%d %H:%M")

            # Create title
            title = f"{fullname} Close Approach to {body}"

            # Create description
            desc_parts = [
                f"Asteroid/Comet {fullname} will make a close approach to {body}.",
                f"Nominal distance: {dist} AU",
            ]
            if dist_min:
                desc_parts.append(f"Minimum distance: {dist_min} AU")
            if v_rel:
                desc_parts.append(f"Relative velocity: {v_rel} km/s")

            description = " ".join(desc_parts)

            # Store all technical details in JSONB
            details = {
                "designation": designation,
                "orbit_id": sbdb_event.get("orbit_id"),
                "julian_date": sbdb_event.get("jd"),
                "nominal_dist_au": dist,
                "dist_min_au": dist_min,
                "dist_max_au": sbdb_event.get("dist_max"),
                "relative_velocity_km_s": v_rel,
                "v_inf": sbdb_event.get("v_inf"),
                "time_sigma": sbdb_event.get("t_sigma_f"),
                "absolute_magnitude": sbdb_event.get("h"),
                "approach_body": body
            }

            return {
                "body_id": designation,  # Will need to map to celestial_bodies.id
                "title": title,
                "event_type": "approach",
                "event_time": event_time,
                "description": description,
                "details": details,
                "source": "nasa_sbdb"
            }

        except Exception as e:
            logger.error(f"Error parsing SBDB event: {e}")
            return None


# Singleton instance
nasa_sbdb_service = NasaSbdbService()