Merge pull request #7081 from Goober5000/wing_destruction_updates

add flag to automatically cancel future waves if a mothership is destroyed

Author: Goober5000

code/ai/ai_flags.h

@@ -188,6 +188,7 @@ namespace AI {
 		Do_not_clear_goals_when_running_stay_still,
 		Do_not_set_override_when_assigning_form_on_wing,
 		Purge_player_issued_form_on_wing_after_subsequent_order,
+		Cancel_future_waves_of_any_wing_launched_from_an_exited_ship,
 
 		NUM_VALUES
 	};

code/ai/ai_profiles.cpp

@@ -742,6 +742,8 @@ void parse_ai_profiles_tbl(const char *filename)
 
 				set_flag(profile, "$purge player-issued form-on-wing after subsequent order:", AI::Profile_Flags::Purge_player_issued_form_on_wing_after_subsequent_order);
 
+				set_flag(profile, "$cancel future waves of any wing launched from an exited ship:", AI::Profile_Flags::Cancel_future_waves_of_any_wing_launched_from_an_exited_ship);
+
 
 				// end of options ----------------------------------------
 
@@ -963,5 +965,6 @@ void ai_profile_t::reset()
 	if (mod_supports_version(25, 0, 0)) {
 		flags.set(AI::Profile_Flags::Fix_avoid_shockwave_bugs);
 		flags.set(AI::Profile_Flags::Purge_player_issued_form_on_wing_after_subsequent_order);
+		flags.set(AI::Profile_Flags::Cancel_future_waves_of_any_wing_launched_from_an_exited_ship);
 	}
 }

code/parse/sexp.cpp

@@ -4218,19 +4218,23 @@ int check_sexp_potential_issues(int node, int *bad_node, SCP_string &issue_msg)
 			case OP_IS_DESTROYED:
 			case OP_TIME_WING_DESTROYED:
 			{
-				for (int n = first_arg_node; n >= 0; n = CDR(n))
+				if (!The_mission.ai_profile->flags[AI::Profile_Flags::Cancel_future_waves_of_any_wing_launched_from_an_exited_ship])
 				{
-					int wingnum = wing_lookup(CTEXT(n));
-					if (wingnum >= 0)
+					for (int n = first_arg_node; n >= 0; n = CDR(n))
 					{
-						auto wingp = &Wings[wingnum];
-						if (wingp->num_waves > 1 && wingp->arrival_location == ArrivalLocation::FROM_DOCK_BAY)
+						int wingnum = wing_lookup(CTEXT(n));
+						if (wingnum >= 0)
 						{
-							issue_msg = "Wing ";
-							issue_msg += wingp->name;
-							issue_msg += " has more than one wave and arrives from a docking bay.  Be careful when checking for this wing's destruction.  If the "
-								"mothership is destroyed before all waves have arrived, the wing will not be considered destroyed.";
-							return SEXP_CHECK_POTENTIAL_ISSUE;
+							auto wingp = &Wings[wingnum];
+							if (wingp->num_waves > 1 && wingp->arrival_location == ArrivalLocation::FROM_DOCK_BAY)
+							{
+								issue_msg = "Wing ";
+								issue_msg += wingp->name;
+								issue_msg += " has more than one wave and arrives from a docking bay.  Be careful when checking for this wing's destruction.  If the "
+									"mothership is destroyed before all waves have arrived, the wing will not be considered destroyed.  Note that the "
+									"$cancel future waves of any wing launched from an exited ship: flag can be used to fix this.";
+								return SEXP_CHECK_POTENTIAL_ISSUE;
+							}
 						}
 					}
 				}

code/ship/ship.cpp

@@ -9267,6 +9267,20 @@ void ship_cleanup(int shipnum, int cleanup_mode)
 		ship_wing_cleanup(shipnum, wingp);
 	}
 
+	// maybe clean up any wings that arrived from this ship
+	if (The_mission.ai_profile->flags[AI::Profile_Flags::Cancel_future_waves_of_any_wing_launched_from_an_exited_ship]) {
+		for (int child_wingnum = 0; child_wingnum < Num_wings; ++child_wingnum) {
+			auto child_wingp = &Wings[child_wingnum];
+			if (child_wingp->arrival_location == ArrivalLocation::FROM_DOCK_BAY && child_wingp->arrival_anchor == shipnum) {
+				// prevent any more waves from arriving by marking this as the last wave
+				child_wingp->num_waves = child_wingp->current_wave;
+
+				// we might need to clean up this wing if there are no ships currently in the mission
+				wing_maybe_cleanup(child_wingp);
+			}
+		}
+	}
+
 	// Note, this call to ai_ship_destroy() must come after ship_wing_cleanup for guarded wings to
 	// properly note the destruction of a ship in their wing.
 	ai_ship_destroy(shipnum);	// Do AI stuff for destruction/leave of ship.