Initial commit: Item Interaction Ecosystem plugin (UE5.7)

Server-authoritative, data-driven item/inventory/interaction/carry/equipment/
world-slot/placement/crafting framework. 8 modules, compiles against UE 5.7.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Source/ItemInventory/Private/ItemCraftingLibrary.cpp

@@ -0,0 +1,98 @@
+// Copyright ExByte Studios. Item Interaction Ecosystem.
+
+#include "ItemCraftingLibrary.h"
+#include "ItemInventoryLog.h"
+#include "InventoryComponent.h"
+#include "ItemDatabaseSubsystem.h"
+#include "ItemContentRows.h"
+
+bool UItemCraftingLibrary::CanCraft(const UObject* WorldContext, UInventoryComponent* Inventory, FName RecipeId, FGameplayTag AvailableStation)
+{
+	const UItemDatabaseSubsystem* DB = UItemDatabaseSubsystem::Get(WorldContext);
+	if (!DB || !Inventory)
+	{
+		return false;
+	}
+	FCraftingRecipeRow Recipe;
+	if (!DB->FindRecipe(RecipeId, Recipe))
+	{
+		return false;
+	}
+	if (Recipe.StationTag.IsValid() && !AvailableStation.MatchesTag(Recipe.StationTag))
+	{
+		return false;
+	}
+	for (const FCraftingIngredient& In : Recipe.Inputs)
+	{
+		if (Inventory->GetItemCount(In.ItemId) < In.Quantity)
+		{
+			return false;
+		}
+	}
+	return true;
+}
+
+bool UItemCraftingLibrary::Craft(const UObject* WorldContext, UInventoryComponent* Inventory, FName RecipeId, FGameplayTag AvailableStation)
+{
+	if (!Inventory || !Inventory->GetOwner() || !Inventory->GetOwner()->HasAuthority())
+	{
+		return false;
+	}
+	if (!CanCraft(WorldContext, Inventory, RecipeId, AvailableStation))
+	{
+		return false;
+	}
+
+	const UItemDatabaseSubsystem* DB = UItemDatabaseSubsystem::Get(WorldContext);
+	FCraftingRecipeRow Recipe;
+	DB->FindRecipe(RecipeId, Recipe);
+
+	// Consume inputs (already verified present).
+	for (const FCraftingIngredient& In : Recipe.Inputs)
+	{
+		if (!ConsumeItem(Inventory, In.ItemId, In.Quantity))
+		{
+			UE_LOG(LogItemInventory, Error, TEXT("Craft '%s' failed mid-consume for %s."), *RecipeId.ToString(), *In.ItemId.ToString());
+			return false;
+		}
+	}
+
+	FItemInstanceData Output = DB->MakeItemInstance(Recipe.OutputItemId, FMath::Max(1, Recipe.OutputQuantity));
+	Inventory->AddItem(Output);
+	UE_LOG(LogItemInventory, Log, TEXT("[Crafting] crafted %s"), *Recipe.OutputItemId.ToString());
+	return true;
+}
+
+void UItemCraftingLibrary::RollLootIntoInventory(const UObject* WorldContext, UInventoryComponent* Inventory, FName TableId, int32 RollCount)
+{
+	const UItemDatabaseSubsystem* DB = UItemDatabaseSubsystem::Get(WorldContext);
+	if (!DB || !Inventory || !Inventory->GetOwner() || !Inventory->GetOwner()->HasAuthority())
+	{
+		return;
+	}
+	TArray<FItemInstanceData> Loot;
+	DB->RollLoot(TableId, RollCount, Loot);
+	for (FItemInstanceData& Item : Loot)
+	{
+		Inventory->AddItem(Item);
+	}
+}
+
+bool UItemCraftingLibrary::ConsumeItem(UInventoryComponent* Inventory, FName ItemId, int32 Count)
+{
+	int32 Remaining = Count;
+	TArray<FItemInstanceData> Items;
+	Inventory->GetAllItems(Items);
+	for (const FItemInstanceData& Item : Items)
+	{
+		if (Remaining <= 0) { break; }
+		if (Item.ItemId != ItemId || Item.Lock.bLocked) { continue; }
+
+		const int32 Take = FMath::Min(Remaining, Item.Quantity);
+		if (Inventory->RemoveQuantity(Item.InstanceId, Take))
+		{
+			Remaining -= Take;
+		}
+	}
+	return Remaining <= 0;
+}