implement unlock dependencies

src/lib/config/ConfigLoader.cpp

@@ -4,6 +4,7 @@
 #include <sstream>
 #include <stdexcept>
 #include <string>
+#include <unordered_set>
 #include <utility>
 #include <vector>
 
@@ -383,6 +384,11 @@ RecipesConfig ConfigLoader::loadRecipes(const std::string& path)
             {
                 def.unlockAtStationLevel = static_cast<int>(*level);
             }
+            if (mt.contains("unlock_requires"))
+            {
+                def.unlockRequires = requireStringArray(mt["unlock_requires"], file,
+                    elemPath + ".unlock_requires");
+            }
         }
 
         // inputs may be omitted (e.g. miner recipes). An empty array is fine.
@@ -422,6 +428,10 @@ ShipsConfig ConfigLoader::loadShips(const std::string& path)
         ShipDef def;
         def.id                 = requireString(mt["id"],                 file, elemPath + ".id");
         def.unlockAtStationLevel = static_cast<int>(requireInt(mt["unlock_at_station_level"], file, elemPath + ".unlock_at_station_level"));
+        if (mt.contains("unlock_requires"))
+        {
+            def.unlockRequires = requireStringArray(mt["unlock_requires"], file, elemPath + ".unlock_requires");
+        }
         def.layout             = requireStringArray(mt["layout"],       file, elemPath + ".layout");
 
         // Schematic
@@ -573,6 +583,10 @@ ModulesConfig ConfigLoader::loadModules(const std::string& path)
         def.id                      = requireString(mt["id"], file, elemPath + ".id");
         def.unlockAtStationLevel    = static_cast<int>(
             mt["unlock_at_station_level"].value_or<int64_t>(-1));
+        if (mt.contains("unlock_requires"))
+        {
+            def.unlockRequires = requireStringArray(mt["unlock_requires"], file, elemPath + ".unlock_requires");
+        }
         def.surfaceMask             = requireStringArray(mt["surface_mask"], file, elemPath + ".surface_mask");
         def.productionTimeSeconds = requireDouble(
             mt["production_time_seconds"], file, elemPath + ".production_time_seconds");
@@ -685,6 +699,67 @@ ModulesConfig ConfigLoader::loadModules(const std::string& path)
     return cfg;
 }
 
+namespace
+{
+
+// Throws if any id in requiredIds is not a valid explicitly-unlockable schematic.
+void checkUnlockRequires(const std::vector<std::string>& requiredIds,
+                         const std::unordered_set<std::string>& schematicIds,
+                         const std::string& file,
+                         const std::string& path)
+{
+    for (const std::string& requiredId : requiredIds)
+    {
+        if (schematicIds.count(requiredId) == 0)
+        {
+            throw makeError(file, path,
+                "references unknown schematic '" + requiredId + "'");
+        }
+    }
+}
+
+// Validates that every id listed in an `unlock_requires` (REQ-LOCK-PREREQ)
+// resolves to an explicitly-unlockable schematic: a ship, a module, or an
+// assembler recipe that carries `unlock_at_station_level` (a recipe schematic,
+// per REQ-LOCK-EXPLICIT). An unresolved id is a config error surfaced at load.
+void validateUnlockRequires(const GameConfig& cfg)
+{
+    std::unordered_set<std::string> schematicIds;
+    for (const ShipDef& def : cfg.ships.ships)
+    {
+        schematicIds.insert(def.id);
+    }
+    for (const ModuleDef& def : cfg.modules.modules)
+    {
+        schematicIds.insert(def.id);
+    }
+    for (const RecipeDef& def : cfg.recipes.recipes)
+    {
+        if (def.building == BuildingType::Assembler && def.unlockAtStationLevel.has_value())
+        {
+            schematicIds.insert(def.id);
+        }
+    }
+
+    for (const ShipDef& def : cfg.ships.ships)
+    {
+        checkUnlockRequires(def.unlockRequires, schematicIds, "ships.toml",
+                            "ship '" + def.id + "'.unlock_requires");
+    }
+    for (const ModuleDef& def : cfg.modules.modules)
+    {
+        checkUnlockRequires(def.unlockRequires, schematicIds, "modules.toml",
+                            "module '" + def.id + "'.unlock_requires");
+    }
+    for (const RecipeDef& def : cfg.recipes.recipes)
+    {
+        checkUnlockRequires(def.unlockRequires, schematicIds, "recipes.toml",
+                            "recipe '" + def.id + "'.unlock_requires");
+    }
+}
+
+} // namespace
+
 GameConfig ConfigLoader::loadFromDirectory(const std::string& configDir)
 {
     GameConfig cfg;
@@ -694,6 +769,7 @@ GameConfig ConfigLoader::loadFromDirectory(const std::string& configDir)
     cfg.ships     = loadShips(configDir + "/ships.toml");
     cfg.stations  = loadStations(configDir + "/stations.toml");
     cfg.modules   = loadModules(configDir + "/modules.toml");
+    validateUnlockRequires(cfg);
     cfg.threatCosts = computeThreatCostTable(cfg);
     return cfg;
 }

src/lib/config/ModulesConfig.h

@@ -41,6 +41,9 @@ struct ModuleDef
 {
     std::string id;
     int unlockAtStationLevel;
+    // Prerequisite schematic ids that must be explicitly unlocked before this
+    // schematic can enter the drop pool (REQ-LOCK-PREREQ). Empty = none.
+    std::vector<std::string> unlockRequires;
     std::vector<std::string> surfaceMask;
     std::vector<RecipeIngredient> materials;
     double productionTimeSeconds;

src/lib/config/RecipesConfig.h

@@ -36,6 +36,10 @@ struct RecipeDef
     // at game start. >= 0 = locked; schematic enters drop pool at that station
     // level once the output item is implicitly unlocked (REQ-LOCK-EXPLICIT).
     std::optional<int> unlockAtStationLevel;
+    // Assembler recipe schematics only. Prerequisite schematic ids that must be
+    // explicitly unlocked before this schematic can enter the drop pool
+    // (REQ-LOCK-PREREQ). Empty = none.
+    std::vector<std::string> unlockRequires;
 };
 
 struct RecipesConfig

src/lib/config/ShipsConfig.h

@@ -36,6 +36,9 @@ struct ShipDef
 {
     std::string id;
     int unlockAtStationLevel;
+    // Prerequisite schematic ids that must be explicitly unlocked before this
+    // schematic can enter the drop pool (REQ-LOCK-PREREQ). Empty = none.
+    std::vector<std::string> unlockRequires;
     std::vector<std::string> layout;
 
     ShipSchematic schematic;