implement building system

src/lib/sim/Building.h

@@ -0,0 +1,76 @@
+#pragma once
+
+#include <map>
+#include <optional>
+#include <string>
+#include <vector>
+
+#include <QPoint>
+#include <QSize>
+
+#include "BuildingType.h"
+#include "EntityId.h"
+#include "Item.h"
+#include "ItemType.h"
+#include "Port.h"
+#include "Rotation.h"
+#include "Tick.h"
+
+// Per-material input buffer for a production building.
+struct InputBuffer
+{
+    std::map<ItemType, int> counts;  // current item counts per material
+    std::map<ItemType, int> caps;    // max items per material (2× per-cycle requirement)
+};
+
+// Output buffer shared by all output materials for a production building.
+struct OutputBuffer
+{
+    std::vector<Item> items;
+    int capacity = 0;  // 2× per-cycle output; 1× for ReprocessingPlant
+};
+
+// Active production cycle for a building.
+struct Production
+{
+    std::string recipeId;
+    Tick completesAt = 0;
+    std::vector<Item> chosenOutputs;  // resolved at cycle start (reprocessing rolls here)
+};
+
+// A building placed on the map that is still under construction.
+// Occupies tiles but does not produce.
+struct ConstructionSite
+{
+    EntityId     id            = kInvalidEntityId;
+    QPoint       anchor;                        // top-left of body bounding box
+    QSize        footprint;
+    std::vector<QPoint> bodyCells;              // absolute world tile coordinates
+    Rotation     rotation      = Rotation::East;
+    BuildingType type          = BuildingType::Miner;
+    std::string  recipeId;                      // may be configured before completion
+    Tick         completesAt   = 0;             // 0 = queued but not yet started
+};
+
+// A fully constructed, operational building.
+struct Building
+{
+    EntityId     id            = kInvalidEntityId;
+    QPoint       anchor;                        // top-left of body bounding box
+    QSize        footprint;
+    Rotation     rotation      = Rotation::East;
+    BuildingType type          = BuildingType::Miner;
+    float        hp            = 0.0f;
+    float        maxHp         = 0.0f;
+    std::string  recipeId;                      // empty = none selected
+
+    InputBuffer  inputBuffer;
+    OutputBuffer outputBuffer;
+    std::optional<Production> production;
+
+    // Pre-computed from surface mask at placement; in absolute world coordinates.
+    std::vector<QPoint> bodyCells;
+    std::vector<Port>   outputPorts;
+    std::vector<Port>   inputPorts;  // perimeter tiles (minus output-port tiles),
+                                     // direction pointing INTO building
+};