brick-framework/GameCore/Inventory/PickupSystem.cs

using GameCore.Combat;
using GameCore.ECS;
using GameCore.ECS.Interfaces;
using GameCore.Events;
using GameCore.Physics;
using GameCore.Player;

namespace GameCore.Inventory;

public class PickupSystem : ISystem
{
    public void Update(World world, float deltaTime)
    {
        var entitiesWithCollisions = world.GetEntitiesWith<CollisionEventComponent>();
        var withCollisions = entitiesWithCollisions.ToList();
        foreach (var entity in withCollisions)
        {
            if (world.GetComponent<PlayerComponent>(entity) == null) return;

            var collision = world.GetComponent<CollisionEventComponent>(entity);
            if (collision == null) continue;

            var pickup = world.GetComponent<PickupComponent>(entity);
            var inventory = world.GetComponent<InventoryComponent>(entity);

            if (pickup == null || inventory == null) continue;

            var item = new Item(pickup.ItemId, pickup.Quantity);
            // In the future, handle IsInstantUse items here
            world.PublishEvent(new AddItemToInventoryEvent(entity, item));
            world.AddComponent(collision.OtherEntity, new DeathComponent());
        }

        foreach (var entity in withCollisions) world.RemoveComponent<CollisionEventComponent>(entity);
    }
}