using System;
using Chernobyl.Destruction;
using UnityEngine;
using UnityEngine.Events;

namespace Chernobyl.Unity.Event
{
    /// <summary>
    /// Forwards events from a <see cref="EventSource"/> to a <see cref="UnityEvent"/>.
    /// </summary>
    public class UnityEventRelay : MonoBehaviour
    {
        /// <summary>
        /// The input source for events
        /// </summary>
        [Tooltip("The input source for events.")]
        public EventSource Source;

        /// <summary>
        /// The <see cref="UnityEvent"/> to invoke when an event is received.
        /// </summary>
        [Tooltip("The UnityEvent to invoke when an event is received.")]
        public UnityEvent Response;

        /// <summary>See Unity docs for more info.</summary>
        public void OnEnable() => _subscription = Source.Observable.Subscribe(arg => Response.Invoke());
        /// <summary>See Unity docs for more info.</summary>
        public void OnDisable() => _subscription.Dispose();
        /// <summary>See Unity docs for more info.</summary>
        public void OnDestroy() => _subscription.Dispose();

        IDisposable _subscription = Disposable.Empty;
    }
}