Cielonos/Assets/Scripts/MainGame/Items/Base/ConsumableBase.cs

using UnityEngine;

namespace Cielonos.MainGame.Inventory
{
    public abstract partial class ConsumableBase : ItemBase
    {
        public int stackAmount;
        public int maximumStack = 99999;
    }
    
    public partial class ConsumableBase
    {
        public void Modify(int amount)
        {
            if (amount > 0)
            {
                Add(amount);
            }
            else if (amount < 0)
            {
                Use(amount);
            }
        }
        
        public void Add(int amount)
        {
            stackAmount += amount;
            if (stackAmount > maximumStack)
            {
                stackAmount = maximumStack;
            }
        }
        
        public bool Use(int amount)
        {
            if (functionSm?.mainFunction != null)
            {
                if (!functionSm.mainFunction.IsAvailable())
                {
                    return false;
                }
            }
            
            if (stackAmount < amount)
            {
                amount = stackAmount;
            }
            
            stackAmount -= amount;
            
            if (stackAmount <= 0)
            {
                player.inventorySc.backpackSm.DiscardItem(this);
            }

            functionSm?.mainFunction?.Execute();
            return true;
        }
    }
}