using Connected.Notifications;
using Connected.Notifications.Events;
using Connected.ServiceModel;

namespace Connected.Services;

public abstract class EntityService<TPrimaryKey> : Service, IServiceNotifications<TPrimaryKey>
{
	public event ServiceEventHandler<PrimaryKeyEventArgs<TPrimaryKey>>? Inserted;
	public event ServiceEventHandler<PrimaryKeyEventArgs<TPrimaryKey>>? Updated;
	public event ServiceEventHandler<PrimaryKeyEventArgs<TPrimaryKey>>? Deleted;

	protected EntityService(IContext context) : base(context)
	{
		if (context.GetService<IEventService>() is IEventService events)
			events.Event += OnEvent;
	}

	private void OnEvent(IOperationState? sender, EventServiceArgs? e)
	{
		if (!e.Service.GetType().IsAssignableTo(GetType()))
			return;

		if (string.Equals(e.Event, nameof(Inserted), StringComparison.Ordinal) && e.Arguments is PrimaryKeyEventArgs<TPrimaryKey> iargs)
			Inserted?.Invoke(sender, iargs);
		else if (string.Equals(e.Event, nameof(Updated), StringComparison.Ordinal) && e.Arguments is PrimaryKeyEventArgs<TPrimaryKey> uargs)
			Inserted?.Invoke(sender, uargs);
		else if (string.Equals(e.Event, nameof(Deleted), StringComparison.Ordinal) && e.Arguments is PrimaryKeyEventArgs<TPrimaryKey> dargs)
			Inserted?.Invoke(sender, dargs);
	}

	protected override void OnDisposing()
	{
		if (Context.GetService<IEventService>() is IEventService events)
			events.Event -= OnEvent;

		base.OnDisposing();
	}
}