using System;

namespace Minigames.StatueDressup
{
    /// <summary>
    /// Interface for managers that load asynchronously and notify when ready.
    /// Allows dependent components to safely access the manager via WhenReady callbacks.
    /// </summary>
    public interface IReadyNotifier
    {
        /// <summary>
        /// True when the manager has finished initialization and is ready to use
        /// </summary>
        bool IsReady { get; }
        
        /// <summary>
        /// Event invoked when the manager becomes ready
        /// </summary>
        event Action OnReady;
    }
    
    /// <summary>
    /// Extension methods for IReadyNotifier to provide common callback behavior
    /// </summary>
    public static class ReadyNotifierExtensions
    {
        /// <summary>
        /// Execute callback when ready. If already ready, executes immediately.
        /// If not ready yet, subscribes to OnReady event and executes when fired.
        /// </summary>
        public static void WhenReady(this IReadyNotifier notifier, Action callback)
        {
            if (notifier == null)
            {
                Core.Logging.Warning("[ReadyNotifierExtensions] Notifier is null, cannot execute callback");
                return;
            }
            
            if (callback == null)
            {
                return;
            }
            
            if (notifier.IsReady)
            {
                // Already ready - execute immediately
                callback.Invoke();
            }
            else
            {
                // Not ready yet - subscribe to event and auto-unsubscribe after invocation
                Action handler = null;
                handler = () =>
                {
                    callback.Invoke();
                    notifier.OnReady -= handler; // Unsubscribe to prevent memory leaks
                };
                notifier.OnReady += handler;
            }
        }
    }
}