[preserve-rooms] fix handling of incoming and offloaded units

docs/changelog.txt

@@ -56,6 +56,8 @@ Template for new versions:
 ## New Features
 
 ## Fixes
+- `preserve-rooms`: don't erroneously release reservations for units that have returned from their missions but have not yet entered the fort map
+- `preserve-rooms`: handle case where unit records are culled by DF immediately after a unit leaves the map
 
 ## Misc Improvements
 

plugins/preserve-rooms.cpp

@@ -394,8 +394,16 @@ static void scrub_reservations(color_ostream &out) {
     vector<int32_t> hfids_to_scrub;
     for (auto &[hfid, zone_ids] : pending_reassignment) {
         auto hf = df::historical_figure::find(hfid);
-        if (hf && hf->died_year == -1 && hf->info && hf->info->whereabouts && hf->info->whereabouts->army_id > -1)
-            continue;
+        if (hf) {
+            // don't scrub alive units that are still in traveling armies
+            if (hf->died_year == -1 && hf->info && hf->info->whereabouts && hf->info->whereabouts->army_id > -1)
+                continue;
+            // don't scrub units that have returned but are not yet active
+            if (auto unit = df::unit::find(hf->unit_id)) {
+                if (unit->flags1.bits.incoming)
+                    continue;
+            }
+        }
         DEBUG(cycle,out).print("removed reservation for dead, culled, or non-army hfid %d: %s\n", hfid,
             hf ? DF2CONSOLE(Units::getReadableName(hf)).c_str() : "culled");
         hfids_to_scrub.push_back(hfid);
@@ -436,26 +444,14 @@ static void handle_missing_assignments(color_ostream &out,
         int32_t hfid = it->second.first;
         int32_t spouse_hfid = it->second.second;
         auto hf = df::historical_figure::find(hfid);
-        if (!hf) {
-            // if the historical figure was culled, bail
-            continue;
-        }
-        auto unit = df::unit::find(hf->unit_id);
-        if (!unit) {
-            // if unit data is completely gone, then they're not likely to come back
-            continue;
-        }
-        if (Units::isActive(unit) && !Units::isDead(unit) && active_unit_ids.contains(unit->id)) {
-            // unit is still alive on the map; assume the unassigment was intentional/expected
-            continue;
-        }
-        if (!Units::isCitizen(unit, true) && !Units::isResident(unit, true)) {
-            // ignore units that are not members of the fort
-            continue;
-        }
-        if (was_expelled(hf)) {
-            // ignore expelled units
+        // if the historical figure was culled, is dead, or was expelled, don't keep a reservation
+        if (!hf || hf->died_year > -1 || was_expelled(hf))
             continue;
+        if (auto unit = df::unit::find(hf->unit_id)) {
+            if (Units::isActive(unit) && !Units::isDead(unit) && active_unit_ids.contains(unit->id)) {
+                // unit is still alive on the map; assume the unassigment was intentional/expected
+                continue;
+            }
         }
         auto zone = virtual_cast<df::building_civzonest>(df::building::find(zone_id));
         if (!zone)
@@ -473,12 +469,12 @@ static void handle_missing_assignments(color_ostream &out,
                 continue;
             }
         }
-        if (Units::isDead(unit))
+        if (hf->died_year > -1)
             continue;
         // register the hf ids for reassignment and reserve the room
         DEBUG(cycle,out).print("registering primary unit for reassignment to zone %d (%s): %d %s\n",
-            zone_id, ENUM_KEY_STR(civzone_type, zone->type).c_str(), unit->id,
-            DF2CONSOLE(Units::getReadableName(unit)).c_str());
+            zone_id, ENUM_KEY_STR(civzone_type, zone->type).c_str(), hf->unit_id,
+            DF2CONSOLE(Units::getReadableName(hf)).c_str());
         pending_reassignment[hfid].push_back(zone_id);
         reserved_zones[zone_id].push_back(hfid);
         if (share_with_spouse && spouse) {
@@ -489,7 +485,7 @@ static void handle_missing_assignments(color_ostream &out,
         }
         INFO(cycle,out).print("preserve-rooms: reserving %s for the return of %s%s%s\n",
                     toLower_cp437(ENUM_KEY_STR(civzone_type, zone->type)).c_str(),
-                    DF2CONSOLE(Units::getReadableName(unit)).c_str(),
+                    DF2CONSOLE(Units::getReadableName(hf)).c_str(),
                     spouse_hf ? " or their spouse, " : "",
                     spouse_hf ? DF2CONSOLE(Units::getReadableName(spouse_hf)).c_str() : "");