read tunnel length from different config and fix tests

src/lib/config/BuildingsConfig.h

@@ -1,6 +1,5 @@
 #pragma once
 
-#include <optional>
 #include <string>
 #include <vector>
 
@@ -19,7 +18,6 @@ struct BuildingDef
     // Stored as raw strings here; parsing into per-cell tiles + output ports
     // happens when buildings are placed, not at load time.
     std::vector<std::string> surfaceMask;
-    std::optional<int> tunnelMaxDistance;
 };
 
 struct BuildingsConfig

src/lib/config/ConfigLoader.cpp

@@ -224,6 +224,7 @@ WorldConfig ConfigLoader::loadWorld(const std::string& path)
     cfg.startingBuildingBlocks     = static_cast<int>(requireInt(tbl["world"]["starting_building_blocks"], file, "world.starting_building_blocks"));
     cfg.scrapDespawnSeconds        = requireDouble(tbl["world"]["scrap_despawn_seconds"], file, "world.scrap_despawn_seconds");
     cfg.beltSpeedTilesPerSecond    = requireDouble(tbl["world"]["belt_speed_tiles_per_second"], file, "world.belt_speed_tiles_per_second");
+    cfg.tunnelMaxDistance          = static_cast<int>(requireInt(tbl["world"]["tunnel_max_distance"], file, "world.tunnel_max_distance"));
 
     cfg.regions.asteroidWidth     = static_cast<int>(requireInt(tbl["regions"]["asteroid_width"],      file, "regions.asteroid_width"));
     cfg.regions.playerBufferWidth = static_cast<int>(requireInt(tbl["regions"]["player_buffer_width"], file, "regions.player_buffer_width"));
@@ -275,11 +276,6 @@ BuildingsConfig ConfigLoader::loadBuildings(const std::string& path)
         def.constructionTimeSeconds = requireDouble(mt["construction_time_seconds"], file, elemPath + ".construction_time_seconds");
         def.surfaceMask             = requireStringArray(mt["surface_mask"],         file, elemPath + ".surface_mask");
 
-        if (const std::optional<int64_t> tmd = mt["tunnel_max_distance"].value<int64_t>())
-        {
-            def.tunnelMaxDistance = static_cast<int>(*tmd);
-        }
-
         const std::optional<BuildingType> parsedType = parseBuildingType(def.id);
         if (!parsedType)
         {

src/lib/config/WorldConfig.h

@@ -42,6 +42,7 @@ struct WorldConfig
     int startingBuildingBlocks;         // REQ-HQ-STARTING-BLOCKS
     double scrapDespawnSeconds;         // REQ-RES-SCRAP-DROP
     double beltSpeedTilesPerSecond;     // REQ-GW-BELT-SPEED
+    int tunnelMaxDistance;              // REQ-BLD-TUNNEL-PAIR
 
     WorldRegions regions;
     WorldExpansion expansion;

src/lib/sim/BuildingSystem.cpp

@@ -427,9 +427,7 @@ void BuildingSystem::tickConstruction(Tick currentTick)
     }
     else if (front.type == BuildingType::TunnelEntry)
     {
-        const BuildingDef* bdef = findBuildingDef(front.type);
-        const int maxDist = (bdef && bdef->tunnelMaxDistance) ? *bdef->tunnelMaxDistance : 0;
-        m_belts.placeTunnelEntry(front.anchor, front.rotation, maxDist);
+        m_belts.placeTunnelEntry(front.anchor, front.rotation, m_config.world.tunnelMaxDistance);
     }
     else if (front.type == BuildingType::TunnelExit)
     {

src/test/ConfigLoaderTest.cpp

@@ -164,6 +164,7 @@ refund_percentage = 75
 scrap_despawn_seconds = 30
 belt_speed_tiles_per_second = 2
 starting_building_blocks = 100
+tunnel_max_distance = 10
 
 [regions]
 asteroid_width = 40
@@ -209,6 +210,7 @@ refund_percentage = 75
 scrap_despawn_seconds = 30
 belt_speed_tiles_per_second = 2
 starting_building_blocks = 100
+tunnel_max_distance = 10
 
 [regions]
 asteroid_width = 40
@@ -322,3 +324,4 @@ duration_seconds = 1.0
         ConfigLoader::loadRecipes((dir.path() / "recipes.toml").string()),
         std::runtime_error);
 }
+

src/test/config/buildings.toml

@@ -12,6 +12,20 @@ player_placeable = true
 construction_time_seconds = 1
 surface_mask = ["<A>"]
 
+[[building]]
+id = "tunnel_entry"
+cost = 5
+player_placeable = true
+construction_time_seconds = 3
+surface_mask = ["A>"]
+
+[[building]]
+id = "tunnel_exit"
+cost = 5
+player_placeable = true
+construction_time_seconds = 3
+surface_mask = ["A>"]
+
 [[building]]
 id = "miner"
 cost = 15

src/test/config/world.toml

@@ -4,6 +4,7 @@ refund_percentage = 75
 starting_building_blocks = 100
 scrap_despawn_seconds = 30
 belt_speed_tiles_per_second = 2
+tunnel_max_distance = 10
 
 [regions]
 asteroid_width = 40