"""
FlightAware AeroAPI tracks worker.
1. Query fr24_ext.schedule for unique flight numbers on target_date
2. GET /aeroapi/flights/{ident} → get fa_flight_id
3. GET /aeroapi/flights/{fa_flight_id}/track → track points
4. Upsert into fr24_ext.flight_tracks_fa + fr24_ext.track_points_fa
"""
import logging
import time
from datetime import date, datetime, timezone
from typing import List, Dict, Optional

import requests
import psycopg2
import psycopg2.extras

from config import config

log = logging.getLogger("fa_worker")

HEADERS = {"x-apikey": config.FA_API_KEY}

_last_request_at: float = 0.0


def _icao_or_none(code: Optional[str]) -> Optional[str]:
    """Return code only if it looks like a valid ICAO airport code (4 uppercase letters).
    FA sometimes returns coordinates like 'L 55.61740 39.72253' instead of ICAO."""
    if code and len(code) == 4 and code.isalpha() and code.isupper():
        return code
    return None


def _throttle():
    global _last_request_at
    elapsed = time.monotonic() - _last_request_at
    if elapsed < config.RATE_LIMIT_SEC:
        time.sleep(config.RATE_LIMIT_SEC - elapsed)
    _last_request_at = time.monotonic()


def _get(path: str, params: dict = None) -> dict:
    _throttle()
    url = f"{config.FA_API_BASE}{path}"
    resp = requests.get(url, headers=HEADERS, params=params, timeout=30)
    if resp.status_code == 429:
        retry_after = int(resp.headers.get("Retry-After", 60))
        log.warning("Rate limited, sleeping %ds", retry_after)
        time.sleep(retry_after)
        return _get(path, params)
    if resp.status_code == 404:
        return {}
    resp.raise_for_status()
    return resp.json()


def get_flights_for_ident(ident: str, target_date: date) -> List[Dict]:
    """GET /aeroapi/flights/{ident} filtered to target_date window."""
    start = f"{target_date}T00:00:00Z"
    end   = f"{target_date}T23:59:59Z"
    data = _get(f"/flights/{ident}", params={"start": start, "end": end})
    return data.get("flights", [])


def get_track(fa_flight_id: str) -> List[Dict]:
    """GET /aeroapi/flights/{fa_flight_id}/track → list of positions."""
    data = _get(f"/flights/{fa_flight_id}/track")
    return data.get("positions", [])


def get_schedule_flights(conn, target_date: date) -> List[Dict]:
    """Return distinct flight_number + airline_iata from schedule for the date."""
    with conn.cursor(cursor_factory=psycopg2.extras.RealDictCursor) as cur:
        cur.execute(
            """
            SELECT DISTINCT flight_number, airline_iata
            FROM fr24_ext.schedule
            WHERE flight_date = %s
              AND flight_number IS NOT NULL
            ORDER BY flight_number
            """,
            (target_date,),
        )
        return [dict(r) for r in cur.fetchall()]


def upsert_flight(conn, fa_flight: Dict, target_date: date) -> Optional[int]:
    """Insert/update FA flight header, return DB id."""
    with conn.cursor() as cur:
        cur.execute(
            """
            INSERT INTO fr24_ext.flight_tracks_fa
              (fa_flight_id, ident_iata, ident_icao, registration, aircraft_type,
               origin_icao, destination_icao, actual_off, actual_on,
               departure_delay, arrival_delay, actual_distance, flight_date)
            VALUES (%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s)
            ON CONFLICT (fa_flight_id) DO UPDATE SET
              ident_iata       = EXCLUDED.ident_iata,
              ident_icao       = EXCLUDED.ident_icao,
              registration     = EXCLUDED.registration,
              aircraft_type    = EXCLUDED.aircraft_type,
              origin_icao      = EXCLUDED.origin_icao,
              destination_icao = EXCLUDED.destination_icao,
              actual_off       = EXCLUDED.actual_off,
              actual_on        = EXCLUDED.actual_on,
              departure_delay  = EXCLUDED.departure_delay,
              arrival_delay    = EXCLUDED.arrival_delay,
              actual_distance  = EXCLUDED.actual_distance,
              fetched_at       = now()
            RETURNING id
            """,
            (
                fa_flight.get("fa_flight_id"),
                fa_flight.get("ident"),
                fa_flight.get("ident_icao"),
                fa_flight.get("registration"),
                fa_flight.get("aircraft_type"),
                _icao_or_none((fa_flight.get("origin") or {}).get("code_icao")),
                _icao_or_none((fa_flight.get("destination") or {}).get("code_icao")),
                fa_flight.get("actual_off"),
                fa_flight.get("actual_on"),
                fa_flight.get("departure_delay"),
                fa_flight.get("arrival_delay"),
                fa_flight.get("route_distance"),
                target_date,
            ),
        )
        row = cur.fetchone()
        return row[0] if row else None


def upsert_track_points(conn, track_id: int, positions: List[Dict]):
    """Delete old points and insert fresh ones. altitude is hundreds of feet → *100."""
    with conn.cursor() as cur:
        cur.execute("DELETE FROM fr24_ext.track_points_fa WHERE track_id = %s", (track_id,))
        if not positions:
            return
        args = [
            (
                track_id,
                p.get("timestamp"),
                p.get("latitude"),
                p.get("longitude"),
                (p["altitude"] * 100) if p.get("altitude") is not None else None,
                p.get("groundspeed"),
                p.get("heading"),
                p.get("update_type"),
            )
            for p in positions
            if p.get("latitude") is not None and p.get("longitude") is not None
        ]
        psycopg2.extras.execute_values(
            cur,
            """
            INSERT INTO fr24_ext.track_points_fa
              (track_id, observed_at, lat, lon, altitude_ft, gspeed_kt, heading, update_type)
            VALUES %s
            """,
            args,
        )


def run(target_date: date, conn) -> Dict:
    """Main entry: load FA tracks for all scheduled flights on target_date."""
    log.info("FA tracks: starting for %s", target_date)
    stats = {
        "date": str(target_date),
        "schedule_flights": 0,
        "fa_flights_found": 0,
        "tracks_loaded": 0,
        "errors": 0,
    }

    schedule_flights = get_schedule_flights(conn, target_date)
    stats["schedule_flights"] = len(schedule_flights)
    log.info("FA tracks: %d unique flights in schedule", len(schedule_flights))

    for sched in schedule_flights:
        ident = sched["flight_number"].replace(" ", "")  # "SU 208" → "SU208"
        try:
            fa_flights = get_flights_for_ident(ident, target_date)
            if not fa_flights:
                log.debug("FA: no flights found for %s", ident)
                continue

            for fa_flight in fa_flights:
                fa_flight_id = fa_flight.get("fa_flight_id")
                if not fa_flight_id:
                    continue

                stats["fa_flights_found"] += 1
                track_id = upsert_flight(conn, fa_flight, target_date)
                if track_id is None:
                    continue

                positions = get_track(fa_flight_id)
                upsert_track_points(conn, track_id, positions)
                conn.commit()
                stats["tracks_loaded"] += 1
                log.debug("FA: %s (%s) → %d points", ident, fa_flight_id, len(positions))

        except Exception as e:
            conn.rollback()
            stats["errors"] += 1
            log.error("FA: error processing %s: %s", ident, e)

    log.info("FA tracks done: %s", stats)
    return stats