Initial implementation of AEW&C missions.

Still a work in progress (the missions don't actually perform their task, just orbit). Currently:

* AEW&C aircraft can be bought.
* AEW&C missions can be planned at any control point and at front lines.
* AEW&C will return after 4H or Bingo.

gen/flights/ai_flight_planner_db.py

@@ -12,8 +12,8 @@ from dcs.helicopters import (
     OH_58D,
     SA342L,
     SA342M,
+    SH_60B,
     UH_1H,
-    SH_60B
 )
 from dcs.planes import (
     AJS37,
@@ -22,11 +22,14 @@ from dcs.planes import (
     A_10C,
     A_10C_2,
     A_20G,
+    A_50,
     B_17G,
     B_1B,
     B_52H,
     Bf_109K_4,
     C_101CC,
+    E_2C,
+    E_3A,
     FA_18C_hornet,
     FW_190A8,
     FW_190D9,
@@ -40,9 +43,11 @@ from dcs.planes import (
     F_4E,
     F_5E_3,
     F_86F_Sabre,
+    I_16,
     JF_17,
     J_11A,
     Ju_88A4,
+    KJ_2000,
     L_39ZA,
     MQ_9_Reaper,
     M_2000C,
@@ -83,18 +88,16 @@ from dcs.planes import (
     Tu_22M3,
     Tu_95MS,
     WingLoong_I,
-    I_16
 )
 from dcs.unittype import FlyingType
 
 from gen.flights.flight import FlightType
-
 from pydcs_extensions.a4ec.a4ec import A_4E_C
 from pydcs_extensions.f22a.f22a import F_22A
-from pydcs_extensions.mb339.mb339 import MB_339PAN
-from pydcs_extensions.rafale.rafale import Rafale_A_S, Rafale_M, Rafale_B
-from pydcs_extensions.su57.su57 import Su_57
 from pydcs_extensions.hercules.hercules import Hercules
+from pydcs_extensions.mb339.mb339 import MB_339PAN
+from pydcs_extensions.rafale.rafale import Rafale_A_S, Rafale_B, Rafale_M
+from pydcs_extensions.su57.su57 import Su_57
 
 # All aircraft lists are in priority order. Aircraft higher in the list will be
 # preferred over those lower in the list.
@@ -155,8 +158,8 @@ CAP_CAPABLE = [
 # Used for CAS (Close air support) and BAI (Battlefield Interdiction)
 CAS_CAPABLE = [
     A_10C_2,
-    A_10C,
     B_1B,
+    A_10C,
     F_14B,
     F_14A_135_GR,
     Su_25TM,
@@ -373,6 +376,13 @@ DRONES = [
     WingLoong_I
 ]
 
+AEWC_CAPABLE = [
+    E_3A,
+    E_2C,
+    A_50,
+    KJ_2000,
+]
+
 
 def aircraft_for_task(task: FlightType) -> List[Type[FlyingType]]:
     cap_missions = (FlightType.BARCAP, FlightType.TARCAP)
@@ -396,6 +406,8 @@ def aircraft_for_task(task: FlightType) -> List[Type[FlyingType]]:
         return STRIKE_CAPABLE
     elif task == FlightType.ESCORT:
         return CAP_CAPABLE
+    elif task == FlightType.AEWC:
+        return AEWC_CAPABLE
     else:
         logging.error(f"Unplannable flight type: {task}")
         return []

gen/flights/flight.py

@@ -20,6 +20,14 @@ if TYPE_CHECKING:
 
 
 class FlightType(Enum):
+    """Enumeration of mission types.
+
+    The value of each enumeration is the name that will be shown in the UI.
+
+    These values are persisted to the save game as well since they are a part of
+    each flight and thus a part of the ATO, so changing these values will break
+    save compat.
+    """
     TARCAP = "TARCAP"
     BARCAP = "BARCAP"
     CAS = "CAS"
@@ -33,6 +41,7 @@ class FlightType(Enum):
     SWEEP = "Fighter sweep"
     OCA_RUNWAY = "OCA/Runway"
     OCA_AIRCRAFT = "OCA/Aircraft"
+    AEWC = "AEW&C"
 
     def __str__(self) -> str:
         return self.value

gen/flights/flightplan.py

@@ -15,6 +15,13 @@ from datetime import timedelta
 from functools import cached_property
 from typing import Iterator, List, Optional, Set, TYPE_CHECKING, Tuple
 
+from dcs.planes import (
+    E_3A,
+    E_2C,
+    A_50,
+    KJ_2000
+)
+
 from dcs.mapping import Point
 from dcs.unit import Unit
 from shapely.geometry import Point as ShapelyPoint
@@ -29,7 +36,7 @@ from game.theater import (
     TheaterGroundObject,
 )
 from game.theater.theatergroundobject import EwrGroundObject
-from game.utils import Distance, Speed, meters, nautical_miles
+from game.utils import Distance, Speed, feet, meters, nautical_miles
 from .closestairfields import ObjectiveDistanceCache
 from .flight import Flight, FlightType, FlightWaypoint, FlightWaypointType
 from .traveltime import GroundSpeed, TravelTime
@@ -121,7 +128,7 @@ class FlightPlan:
         failed to generate. Nevertheless, we have to defend against it.
         """
         raise NotImplementedError
-    
+
     @cached_property
     def bingo_fuel(self) -> int:
         """Bingo fuel value for the FlightPlan
@@ -145,7 +152,7 @@ class FlightPlan:
         """Joker fuel value for the FlightPlan
         """
         return self.bingo_fuel + 1000
-   
+
     def max_distance_from(self, cp: ControlPoint) -> Distance:
         """Returns the farthest waypoint of the flight plan from a ControlPoint.
         :arg cp The ControlPoint to measure distance from.
@@ -280,11 +287,11 @@ class LoiterFlightPlan(FlightPlan):
         travel_time = super().travel_time_between_waypoints(a, b)
         if a != self.hold:
             return travel_time
-        try:
-            return travel_time + self.hold_duration
-        except AttributeError:
-            # Save compat for 2.3.
-            return travel_time + timedelta(minutes=5)
+        return travel_time + self.hold_duration
+
+    @property
+    def mission_departure_time(self) -> timedelta:
+        raise NotImplementedError
 
 
 @dataclass(frozen=True)
@@ -542,10 +549,10 @@ class StrikeFlightPlan(FormationFlightPlan):
     @property
     def package_speed_waypoints(self) -> Set[FlightWaypoint]:
         return {
-           self.ingress,
-           self.egress,
-           self.split,
-        } | set(self.targets)
+                   self.ingress,
+                   self.egress,
+                   self.split,
+               } | set(self.targets)
 
     def speed_between_waypoints(self, a: FlightWaypoint,
                                 b: FlightWaypoint) -> Speed:
@@ -696,6 +703,41 @@ class SweepFlightPlan(LoiterFlightPlan):
         return self.sweep_end_time
 
 
+@dataclass(frozen=True)
+class AwacsFlightPlan(LoiterFlightPlan):
+    takeoff: FlightWaypoint
+    nav_to: List[FlightWaypoint]
+    nav_from: List[FlightWaypoint]
+    land: FlightWaypoint
+    divert: Optional[FlightWaypoint]
+
+    def iter_waypoints(self) -> Iterator[FlightWaypoint]:
+        yield self.takeoff
+        yield from self.nav_to
+        yield self.hold
+        yield from self.nav_from
+        yield self.land
+        if self.divert is not None:
+            yield self.divert
+
+    def tot_for_waypoint(self, waypoint: FlightWaypoint) -> Optional[timedelta]:
+        if waypoint == self.hold:
+            return self.package.time_over_target
+        return None
+
+    @property
+    def tot_waypoint(self) -> Optional[FlightWaypoint]:
+        return self.hold
+
+    @property
+    def push_time(self) -> timedelta:
+        return self.package.time_over_target + self.hold_duration
+
+    @property
+    def mission_departure_time(self) -> timedelta:
+        return self.push_time
+
+
 @dataclass(frozen=True)
 class CustomFlightPlan(FlightPlan):
     custom_waypoints: List[FlightWaypoint]
@@ -791,6 +833,8 @@ class FlightPlanBuilder:
             return self.generate_sweep(flight)
         elif task == FlightType.TARCAP:
             return self.generate_tarcap(flight)
+        elif task == FlightType.AEWC:
+            return self.generate_aewc(flight)
         raise PlanningError(
             f"{task} flight plan generation not implemented")
 
@@ -921,6 +965,45 @@ class FlightPlanBuilder:
                                       FlightWaypointType.INGRESS_STRIKE,
                                       targets)
 
+    def generate_aewc(self, flight: Flight) -> AwacsFlightPlan:
+        """Generate a AWACS flight at a given location.
+
+       Args:
+           flight: The flight to generate the flight plan for.
+       """
+        location = self.package.target
+
+        start = self.aewc_orbit(location)
+
+        # As high as possible to maximize detection and on-station time.
+        if flight.unit_type == E_2C:
+            patrol_alt = feet(30000)
+        elif flight.unit_type == E_3A:
+            patrol_alt = feet(35000)
+        elif flight.unit_type == A_50:
+            patrol_alt = feet(33000)
+        elif flight.unit_type == KJ_2000:
+            patrol_alt = feet(40000)
+        else:
+            patrol_alt = feet(25000)
+
+        builder = WaypointBuilder(flight, self.game, self.is_player)
+        start = builder.orbit(start, patrol_alt)
+
+        return AwacsFlightPlan(
+            package=self.package,
+            flight=flight,
+            takeoff=builder.takeoff(flight.departure),
+            nav_to=builder.nav_path(flight.departure.position, start.position,
+                                    patrol_alt),
+            nav_from=builder.nav_path(start.position, flight.arrival.position,
+                                      patrol_alt),
+            land=builder.land(flight.arrival),
+            divert=builder.divert(flight.divert),
+            hold=start,
+            hold_duration=timedelta(hours=4),
+        )
+
     def generate_bai(self, flight: Flight) -> StrikeFlightPlan:
         """Generates a BAI flight plan.
 
@@ -1095,6 +1178,18 @@ class FlightPlanBuilder:
         start = end.point_from_heading(heading - 180, diameter)
         return start, end
 
+    @staticmethod
+    def aewc_orbit(location: MissionTarget) -> Point:
+        closest_airfield = location
+        # TODO: This is a heading to itself.
+        # Place this either over the target or as close as possible outside the
+        # threat zone: https://github.com/Khopa/dcs_liberation/issues/842.
+        heading = location.position.heading_between_point(closest_airfield.position)
+        return location.position.point_from_heading(
+            heading,
+            5000
+        )
+
     def racetrack_for_frontline(self, origin: Point,
                                 front_line: FrontLine) -> Tuple[Point, Point]:
         ally_cp, enemy_cp = front_line.control_points

gen/flights/waypointbuilder.py

@@ -366,6 +366,26 @@ class WaypointBuilder:
         return (self.race_track_start(start, altitude),
                 self.race_track_end(end, altitude))
 
+    @staticmethod
+    def orbit(start: Point, altitude: Distance) -> FlightWaypoint:
+        """Creates an circular orbit point.
+
+        Args:
+            start: Position of the waypoint.
+            altitude: Altitude of the racetrack.
+        """
+
+        waypoint = FlightWaypoint(
+            FlightWaypointType.LOITER,
+            start.x,
+            start.y,
+            altitude
+        )
+        waypoint.name = "ORBIT"
+        waypoint.description = "Anchor and hold at this point"
+        waypoint.pretty_name = "Orbit"
+        return waypoint
+
     @staticmethod
     def sweep_start(position: Point, altitude: Distance) -> FlightWaypoint:
         """Creates a sweep start waypoint.