//represent an item in creature's inventory.
public abstract class UsableItem : Item, IListenToAction
{
	protected ButtonState m_ButtonState;
	protected int m_CurrentActionIndex;

	public Action myAction { get; protected set; }

	protected override void StartImp()
	{
		base.StartImp();
		m_ActiveState = false;
	}

	#region Item state
	protected override void OnAquiredByInventory()
	{
		base.OnAquiredByInventory();
		myAction.SetOwner(owner);
	}

	protected override void OnDroppedByInventory()
	{
		base.OnDroppedByInventory();
		myAction.SetOwner(null);
		m_ButtonState = ButtonState.empty;
	}
	#endregion

	#region item trigger

	/// <summary>
	/// state represent button state, or something else. maybe used in certain item.
	/// for example, continues attack.
	/// </summary>
	public void UseAction(ButtonState buttonState, int actionIndex = 0)
	{
		if (m_ActiveState)
		{
			m_ButtonState = buttonState;
			m_CurrentActionIndex = actionIndex;
			InternalUseAction(actionIndex, m_ButtonState);
		}
	}

	protected abstract void InternalUseAction(int actionIndex, ButtonState buttonState);
	#endregion


	#region IUseAction Impl 
	public virtual void OnActionBegin() { }

	public virtual void OnActionAbort(ActionAbortType actionAbortType)	{ }

	// @Note: all override method must use base.OnReachEvent(...)
	public virtual void OnReachEvent(int evtId, string param1, string param2, string param3)
	{
		if (evtId == E.costStamina)
		{
			owner.action.EmitConsumeStamina(param1.EvtToFloat());
			//Debug.Log("Emitting consume stamina signal!");
		}
	}
	#endregion
}