Remove GroundPlanners from the save state.

These are only used during mission generation. Remove them from the save
state to reduce compatibility requirements. We also have at least one
report of this data being corrupted... somehow. I don't know how that
could have happened, but if there's no data to corrupt in the first
place that's not a problem. If the corruption _does_ recur, it'll be
much easier to repro if it corrupts during mission generation rather
than during turn initialization.

Fixes https://github.com/dcs-liberation/dcs_liberation/issues/2729.

changelog.md

@@ -19,6 +19,7 @@ Saves from 6.x are not compatible with 7.0.
 * **[Modding]** Fixed an issue where Falklands campaigns created or edited with new versions of DCS could not be loaded.
 * **[Modding]** Fixed decoding of campaign yaml files to use UTF-8 rather than the system locale's default. It's now possible to use "Bf 109 K-4 Kurfürst" as a preferred aircraft type.
 * **[Mission Generation]** Planes will no longer spawn in helipads that are not also designated for fixed wing parking.
+* **[Mission Generation]** Potentially an issue where ground war planning game state could become corrupted, preventing mission generation.
 
 # 6.1.1
 

game/game.py

@@ -7,7 +7,6 @@ from collections.abc import Iterator
 from datetime import date, datetime, time, timedelta
 from enum import Enum
 from typing import Any, List, TYPE_CHECKING, Type, Union, cast
-from uuid import UUID
 
 from dcs.countries import Switzerland, USAFAggressors, UnitedNationsPeacekeepers
 from dcs.country import Country
@@ -17,7 +16,6 @@ from dcs.vehicles import AirDefence
 from faker import Faker
 
 from game.ato.closestairfields import ObjectiveDistanceCache
-from game.ground_forces.ai_ground_planner import GroundPlanner
 from game.models.game_stats import GameStats
 from game.plugins import LuaPluginManager
 from game.utils import Distance
@@ -109,7 +107,6 @@ class Game:
         self.date = date(start_date.year, start_date.month, start_date.day)
         self.game_stats = GameStats()
         self.notes = ""
-        self.ground_planners: dict[UUID, GroundPlanner] = {}
         self.informations: list[Information] = []
         self.message("Game Start", "-" * 40)
         # Culling Zones are for areas around points of interest that contain things we may not wish to cull.
@@ -432,14 +429,6 @@ class Game:
         if for_red:
             self.red.initialize_turn()
 
-        # Plan GroundWar
-        self.ground_planners = {}
-        for cp in self.theater.controlpoints:
-            if cp.has_frontline:
-                gplanner = GroundPlanner(cp, self)
-                gplanner.plan_groundwar()
-                self.ground_planners[cp.id] = gplanner
-
         # Update cull zones
         with logged_duration("Computing culling positions"):
             self.compute_unculled_zones(events)

game/missiongenerator/missiongenerator.py

@@ -13,6 +13,7 @@ from dcs.countries import country_dict
 from game.atcdata import AtcData
 from game.dcs.beacons import Beacons
 from game.dcs.helpers import unit_type_from_name
+from game.ground_forces.ai_ground_planner import GroundPlanner
 from game.missiongenerator.aircraft.aircraftgenerator import (
     AircraftGenerator,
 )
@@ -42,7 +43,8 @@ from .visualsgenerator import VisualsGenerator
 
 if TYPE_CHECKING:
     from game import Game
-
+    from game.theater import ControlPoint
+    from game.ground_forces.ai_ground_planner import CombatGroup
 
 COMBINED_ARMS_SLOTS = 1
 
@@ -189,8 +191,33 @@ class MissionGenerator:
                 # No need to reserve ILS or TACAN because those are in the
                 # beacon list.
 
+    def _find_combat_groups_between(
+        self,
+        planners: dict[ControlPoint, GroundPlanner],
+        origin: ControlPoint,
+        target: ControlPoint,
+    ) -> list[CombatGroup]:
+        try:
+            planner = planners[origin]
+        except KeyError as ex:
+            raise KeyError(f"No ground planner found at {origin}") from ex
+
+        try:
+            return planner.units_per_cp[target.id]
+        except KeyError as ex:
+            raise KeyError(
+                f"Ground planner at {origin} does not target {target}"
+            ) from ex
+
     def generate_ground_conflicts(self) -> None:
         """Generate FLOTs and JTACs for each active front line."""
+        planners: dict[ControlPoint, GroundPlanner] = {}
+        for control_point in self.game.theater.controlpoints:
+            if control_point.has_frontline:
+                planner = GroundPlanner(control_point, self.game)
+                planners[control_point] = planner
+                planner.plan_groundwar()
+
         for front_line in self.game.theater.conflicts():
             player_cp = front_line.blue_cp
             enemy_cp = front_line.red_cp
@@ -198,16 +225,12 @@ class MissionGenerator:
                 front_line, self.game.theater
             )
             # Generate frontline ops
-            player_gp = self.game.ground_planners[player_cp.id].units_per_cp[
-                enemy_cp.id
-            ]
-            enemy_gp = self.game.ground_planners[enemy_cp.id].units_per_cp[player_cp.id]
             ground_conflict_gen = FlotGenerator(
                 self.mission,
                 conflict,
                 self.game,
-                player_gp,
-                enemy_gp,
+                self._find_combat_groups_between(planners, player_cp, enemy_cp),
+                self._find_combat_groups_between(planners, enemy_cp, player_cp),
                 player_cp.stances[enemy_cp.id],
                 enemy_cp.stances[player_cp.id],
                 self.unit_map,