implement building system

src/lib/sim/BuildingSystem.h

@@ -0,0 +1,88 @@
+#pragma once
+
+#include <deque>
+#include <functional>
+#include <map>
+#include <optional>
+#include <random>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include <QPoint>
+
+#include "BeltSystem.h"
+#include "Building.h"
+#include "BuildingType.h"
+#include "EntityId.h"
+#include "GameConfig.h"
+#include "Rotation.h"
+#include "Tick.h"
+
+// Manages building placement, construction queuing, and the per-tick
+// production loop (belt→building pull, production, building→belt push).
+// Belt and Splitter types are forwarded to BeltSystem rather than stored
+// as Building instances.
+class BuildingSystem
+{
+public:
+    BuildingSystem(const GameConfig& config,
+                   BeltSystem& belts,
+                   std::function<EntityId()> allocateId,
+                   std::function<void(int)> addBuildingBlocks,
+                   std::mt19937& rng);
+
+    // -- Placement / demolish ------------------------------------------------
+    // Returns the new entity id.  Belt and Splitter register with BeltSystem
+    // directly; other types enter the construction queue.
+    EntityId place(BuildingType type, QPoint anchor, Rotation rotation,
+                   Tick currentTick);
+
+    // Remove a building or construction site by id.  Returns the refund in
+    // building blocks (floor(cost * refundPercentage / 100)).  Returns 0 for
+    // unknown ids.
+    int demolish(EntityId id);
+
+    // Set the recipe (or blueprint id for shipyard) on a building or queued
+    // construction site.  Clears both buffers on an operational building.
+    void setRecipe(EntityId id, const std::string& recipeId);
+
+    // -- Tick hooks (called from Simulation::tick in the documented order) ---
+    void tickConstruction(Tick currentTick);
+    void tickBeltPull();
+    void tickProduction(Tick currentTick);
+    void tickBeltPush();
+
+    // -- Queries -------------------------------------------------------------
+    const Building*           findBuilding(EntityId id)  const;
+    const ConstructionSite*   findSite(EntityId id)      const;
+    std::vector<Building>     allBuildings()             const;
+    std::vector<ConstructionSite> allSites()             const;
+    bool                      isTileOccupied(QPoint tile) const;
+
+private:
+    struct BeltEntry
+    {
+        QPoint       tile;
+        BuildingType type;  // Belt or Splitter
+    };
+
+    const BuildingDef*  findBuildingDef(BuildingType type) const;
+    const RecipeDef*    findRecipe(const std::string& id, BuildingType type) const;
+    void                initBuffers(Building& b, const RecipeDef& recipe) const;
+    std::vector<Port>   computeInputPorts(const Building& b) const;
+    std::vector<Item>   rollReprocessingOutput(const RecipeDef& recipe);
+
+    const GameConfig&           m_config;
+    BeltSystem&                 m_belts;
+    std::function<EntityId()>   m_allocateId;
+    std::function<void(int)>    m_addBuildingBlocks;
+    std::mt19937&               m_rng;
+
+    std::vector<Building>           m_buildings;
+    std::deque<ConstructionSite>    m_constructionQueue;
+    std::map<EntityId, BeltEntry>   m_beltEntities;
+
+    // Maps every occupied body-cell coordinate to the entity that owns it.
+    std::map<std::pair<int, int>, EntityId> m_tileOccupancy;
+};