from __future__ import annotations

from datetime import timedelta
from typing import Optional, TYPE_CHECKING

from dcs import Point
from shapely.geometry import LineString, Point as ShapelyPoint

from game.ato import FlightType
from game.ato.flightstate import InFlight
from game.threatzones import ThreatPoly
from game.utils import Distance, Speed
from gen.flights.flightplan import PatrollingFlightPlan

if TYPE_CHECKING:
    from game.ato.flight import Flight
    from game.settings import Settings


class RaceTrack(InFlight):
    def __init__(self, flight: Flight, settings: Settings, waypoint_index: int) -> None:
        assert isinstance(flight.flight_plan, PatrollingFlightPlan)
        self.patrol_duration = flight.flight_plan.patrol_duration
        super().__init__(flight, settings, waypoint_index)
        self.commit_region = LineString(
            [
                ShapelyPoint(self.current_waypoint.x, self.current_waypoint.y),
                ShapelyPoint(self.next_waypoint.x, self.next_waypoint.y),
            ]
        ).buffer(flight.flight_plan.engagement_distance.meters)

    def estimate_position(self) -> Point:
        # Prevent spawning racetracks in the middle of a leg. For simplicity we
        # always start the aircraft at the beginning of the racetrack.
        return self.current_waypoint.position

    def estimate_altitude(self) -> tuple[Distance, str]:
        return self.current_waypoint.alt, self.current_waypoint.alt_type

    def estimate_speed(self) -> Speed:
        return self.flight.unit_type.preferred_patrol_speed(self.estimate_altitude()[0])

    def travel_time_between_waypoints(self) -> timedelta:
        return self.patrol_duration

    def a2a_commit_region(self) -> Optional[ThreatPoly]:
        if self.flight.flight_type in {FlightType.BARCAP, FlightType.TARCAP}:
            return self.commit_region
        return None