Fix invalid tanker planning.

All three refueling missions share a common task type and differentiate
their behavior based on the type and allegiance of the package target.
This means that if the theater commander identifies a carrier as the
best location for a theater refueling task, a recovery tanker will be
planned by mistake.

If this happens on a sunken carrier, mission generation will fail
because a recovery tanker cannot be generated for a sunken carrier.

Fix the crash and the misplanned theater tanker by preventing the
commander from choosing fleet control points as refueling targets.

Fixes https://github.com/dcs-liberation/dcs_liberation/issues/2693.

(cherry picked from commit eea98b01f6e7311969bae08325fd38345dfbedb1)

changelog.md

@@ -3,6 +3,7 @@
 ## Fixes
 
 * **[Data]** Fixed unit ID for the KS-19 AAA. KS-19 would not previously generate correctly in missions. A new game is required for this fix to take effect.
+* **[Flight Planning]** Automatic flight planning will no longer accidentally plan a recovery tanker instead of a theater refueling package. This fixes a potential crash during mission generation when opfor plans a refueling task at a sunk carrier. You'll need to skip the current turn to force opfor to replan their flights to get the fix.
 
 # 6.1.0
 

game/commander/objectivefinder.py

@@ -5,6 +5,7 @@ import operator
 from collections.abc import Iterable, Iterator
 from typing import TYPE_CHECKING, TypeVar
 
+from game.ato.closestairfields import ClosestAirfields, ObjectiveDistanceCache
 from game.theater import (
     Airfield,
     ControlPoint,
@@ -15,12 +16,11 @@ from game.theater import (
 )
 from game.theater.theatergroundobject import (
     BuildingGroundObject,
+    IadsBuildingGroundObject,
     IadsGroundObject,
     NavalGroundObject,
-    IadsBuildingGroundObject,
 )
 from game.utils import meters, nautical_miles
-from game.ato.closestairfields import ClosestAirfields, ObjectiveDistanceCache
 
 if TYPE_CHECKING:
     from game import Game
@@ -209,22 +209,20 @@ class ObjectiveFinder:
             raise RuntimeError("Found no friendly control points. You probably lost.")
         return farthest
 
-    def closest_friendly_control_point(self) -> ControlPoint:
+    def preferred_theater_refueling_control_point(self) -> ControlPoint | None:
         """Finds the friendly control point that is closest to any threats."""
         threat_zones = self.game.threat_zone_for(not self.is_player)
 
         closest = None
         min_distance = meters(math.inf)
         for cp in self.friendly_control_points():
-            if isinstance(cp, OffMapSpawn):
+            if isinstance(cp, OffMapSpawn) or cp.is_fleet:
                 continue
             distance = threat_zones.distance_to_threat(cp.position)
             if distance < min_distance:
                 closest = cp
                 min_distance = distance
 
-        if closest is None:
-            raise RuntimeError("Found no friendly control points. You probably lost.")
         return closest
 
     def enemy_control_points(self) -> Iterator[ControlPoint]:

game/commander/theaterstate.py

@@ -153,6 +153,11 @@ class TheaterState(WorldState["TheaterState"]):
         barcap_duration = coalition.doctrine.cap_duration.total_seconds()
         barcap_rounds = math.ceil(mission_duration / barcap_duration)
 
+        refueling_targets: list[MissionTarget] = []
+        theater_refuling_point = finder.preferred_theater_refueling_control_point()
+        if theater_refuling_point is not None:
+            refueling_targets.append(theater_refuling_point)
+
         return TheaterState(
             context=context,
             barcaps_needed={
@@ -162,7 +167,7 @@ class TheaterState(WorldState["TheaterState"]):
             front_line_stances={f: None for f in finder.front_lines()},
             vulnerable_front_lines=list(finder.front_lines()),
             aewc_targets=[finder.farthest_friendly_control_point()],
-            refueling_targets=[finder.closest_friendly_control_point()],
+            refueling_targets=refueling_targets,
             enemy_air_defenses=list(finder.enemy_air_defenses()),
             threatening_air_defenses=[],
             detecting_air_defenses=[],

game/missiongenerator/aircraft/waypoints/recoverytanker.py

@@ -31,10 +31,11 @@ class RecoveryTankerBuilder(PydcsWaypointBuilder):
         for key, value in theater_objects.items():
             # Check name and position in case there are multiple of same carrier.
             if name in key and value.theater_unit.position == carrier_position:
-                theater_mapping = value
-                break
-        assert theater_mapping is not None
-        return theater_mapping.dcs_group_id
+                return value.dcs_group_id
+        raise RuntimeError(
+            f"Could not find a carrier in the mission matching {name} at "
+            f"({carrier_position.x}, {carrier_position.y})"
+        )
 
     def configure_tanker_tacan(self, waypoint: MovingPoint) -> None: