#nullable enable
using System;
using System.Windows.Input;
using Microsoft.Maui.Controls.Internals;
 
namespace Microsoft.Maui.Controls
{
	static class CommandElement
	{
		public static void OnCommandChanging(BindableObject bo, object o, object n)
		{
			var commandElement = (ICommandElement)bo;
			if (o is ICommand oldCommand)
				oldCommand.CanExecuteChanged -= commandElement.CanExecuteChanged;
		}
 
		public static void OnCommandChanged(BindableObject bo, object o, object n)
		{
			var commandElement = (ICommandElement)bo;
			if (n is ICommand newCommand)
				newCommand.CanExecuteChanged += commandElement.CanExecuteChanged;
			commandElement.CanExecuteChanged(bo, EventArgs.Empty);
		}
 
		public static void OnCommandParameterChanged(BindableObject bo, object o, object n)
		{
			var commandElement = (ICommandElement)bo;
			commandElement.CanExecuteChanged(bo, EventArgs.Empty);
		}
 
		public static bool GetCanExecute(ICommandElement commandElement)
		{
			if (commandElement.Command == null)
				return true;
 
			return commandElement.Command.CanExecute(commandElement.CommandParameter);
		}
	}
}