riversong code showcase

Source/Riversong/Game/World/Production/ProductionRequirementsGameSystem.cs

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+
+namespace DanieleMarotta.RiversongCodeShowcase
+{
+    [GameSystemGroup(typeof(EconomySystemGroup))]
+    public class ProductionRequirementsGameSystem : GameSystem, IUpdatable
+    {
+        [InjectService]
+        private IEntityCache _entityCache;
+
+        public ProductionRequirementsGameSystem(IServiceLocator serviceLocator) : base(serviceLocator)
+        {
+        }
+
+        public void Update()
+        {
+            foreach (var producer in _entityCache.GetProducers())
+            {
+                ref var productionState = ref producer.GetProductionStateRW();
+                ref var recipe = ref productionState.Recipe;
+                ref var storage = ref producer.GetStorageRW();
+
+                productionState.MetRequirements = ProductionRequirements.All;
+
+                foreach (var (product, amount) in recipe.Inputs)
+                    if (storage.AvailableNow(product) < amount)
+                    {
+                        productionState.MetRequirements &= ~ProductionRequirements.InputsAvailable;
+                        break;
+                    }
+            }
+        }
+    }
+}