Mobile Game Crafting System Development

Mobile Game Crafting System Development

Crafting system—mechanic where player combines resources or items for new item. From simple "3 wood + 2 iron = sword" to multi-level recipe trees with probability outcomes and time mechanics. Implementation complexity determined not by UI but data architecture: recipes, inventory, craft state, server validation.

Recipe Data Architecture

Store recipes as data, not logic in code. This allows adding new recipes without app update via Remote Config or Addressables:

[Serializable]
public class CraftingRecipe
{
    public string recipeId;
    public string resultItemId;
    public int resultQuantity;
    public List<Ingredient> ingredients;
    public float craftingTime;  // seconds, 0 = instant
    public float successRate;   // 0.0-1.0, 1.0 = always
    public string requiredStation; // "forge", "alchemy_table", null = everywhere
    public int requiredLevel;
}

[Serializable]
public class Ingredient
{
    public string itemId;
    public int quantity;
    public bool consumed;  // false = tool, not consumed
}

Recipe list loads on startup from ScriptableObject or Addressables.LoadAssetAsync<CraftingDatabase>. For balance tuning without update—Remote Config stores JSON with overrides patching defaults.

CraftingManager: Core Logic

public class CraftingManager : MonoBehaviour
{
    public static CraftingManager Instance { get; private set; }

    private CraftingDatabase _database;
    private InventoryManager _inventory;

    public CraftingResult TryCraft(string recipeId, string stationId = null)
    {
        var recipe = _database.GetRecipe(recipeId);
        if (recipe == null) return CraftingResult.InvalidRecipe;

        // Check station
        if (!string.IsNullOrEmpty(recipe.requiredStation) && recipe.requiredStation != stationId)
            return CraftingResult.WrongStation;

        // Check level
        if (PlayerData.Level < recipe.requiredLevel)
            return CraftingResult.LevelTooLow;

        // Check ingredients
        foreach (var ingredient in recipe.ingredients)
        {
            if (_inventory.GetCount(ingredient.itemId) < ingredient.quantity)
                return CraftingResult.MissingIngredients;
        }

        // Success probability
        bool success = Random.value <= recipe.successRate;

        // Consume only consumed ingredients
        foreach (var ingredient in recipe.ingredients.Where(i => i.consumed))
            _inventory.Remove(ingredient.itemId, ingredient.quantity);

        if (success)
            _inventory.Add(recipe.resultItemId, recipe.resultQuantity);

        // Analytics
        GameAnalytics.NewDesignEvent($"Crafting:Result:{recipeId}", success ? 1 : 0);

        return success ? CraftingResult.Success : CraftingResult.Failed;
    }
}

Crafting with Timer

For "start craft, return in an hour" mechanic:

public class CraftingSlot
{
    public string recipeId;
    public DateTime completionTime;
    public bool isComplete => DateTime.UtcNow >= completionTime;
}

public void StartCrafting(string recipeId, int slotIndex)
{
    var recipe = _database.GetRecipe(recipeId);
    _craftingSlots[slotIndex] = new CraftingSlot
    {
        recipeId = recipeId,
        completionTime = DateTime.UtcNow.AddSeconds(recipe.craftingTime)
    };

    // Save in PlayerPrefs or Cloud Save
    SaveCraftingState();

    // Schedule local notification
    NotificationManager.ScheduleLocal(
        $"Crafting complete: {recipe.resultItemId}",
        recipe.craftingTime
    );
}

Slot state must persist—if player closes app, timer continues. For offline progress use DateTime.UtcNow on next launch: if completionTime < DateTime.UtcNow—craft complete.

Server Validation

For monetized games crafting can't fully trust client. Classic pattern via PlayFab Cloud Script:

// PlayFab Cloud Script
handlers.CraftItem = function(args) {
    var recipeId = args.recipeId;
    var recipe = getRecipeFromCatalog(recipeId);

    // Check inventory on server
    var inventory = server.GetUserInventory({ PlayFabId: currentPlayerId });
    for (var ingredient of recipe.ingredients) {
        var count = countItem(inventory, ingredient.itemId);
        if (count < ingredient.quantity) {
            return { success: false, error: "insufficient_items" };
        }
    }

    // Consume and grant on server
    for (var ingredient of recipe.ingredients.filter(i => i.consumed)) {
        server.RevokeInventoryItems({ ... });
    }
    server.GrantItemsToUser({ itemIds: [recipe.resultItemId], ... });

    return { success: true, resultItemId: recipe.resultItemId };
};

What's Included

• Recipe data schema and inventory design
• CraftingManager implementation with checks and probabilities
• Crafting with timers and offline progression
• Local push notifications on craft completion
• Server validation via PlayFab / GameSparks (if needed)
• UI: recipe book, craft slots, progress bar
• Analytics events for recipe popularity balancing

Timeline

Basic instant crafting: 3–5 days. Full system with timers, slots, server validation, and UI: 1.5–3 weeks. Cost calculated individually.