brick-framework/GameCore/Inventory/ItemAcquisitionSystem.cs

using GameCore.Combat;
using GameCore.Combat.Effects;
using GameCore.ECS;
using GameCore.ECS.Interfaces;
using GameCore.Events;

namespace GameCore.Inventory;

public class ItemAcquisitionSystem : ISystem
{
    private readonly World _world;

    public ItemAcquisitionSystem(World world)
    {
        _world = world;
        _world.Subscribe<ItemPickupAttemptEvent>(OnItemPickupAttempt);
    }

    public void Update(World world, float deltaTime)
    {
    }

    private void OnItemPickupAttempt(ItemPickupAttemptEvent e)
    {
        var pickupComponent = _world.GetComponent<PickupComponent>(e.ItemEntity);
        if (pickupComponent == null) return;

        if (pickupComponent.IsInstantUse)
        {
            var context = new EffectContext
            {
                World = _world,
                Owner = e.Picker,
                Target = e.Picker
            };

            foreach (var effect in pickupComponent.OnAcquireEffects) effect.Execute(context);
        }
        else
        {
            var item = new Item(e.ItemId, e.Quantity);
            _world.PublishEvent(new AddItemToInventoryEvent(e.Picker, item));
        }

        _world.AddComponent(e.ItemEntity, new DeathComponent());
    }
}