using System.Windows.Input;

namespace LanMountainDesktop.Launcher.ViewModels;

/// <summary>
/// 简单的命令实现
/// </summary>
public class RelayCommand : ICommand
{
    private readonly Action _execute;
    private readonly Func<bool>? _canExecute;

    public RelayCommand(Action execute, Func<bool>? canExecute = null)
    {
        _execute = execute ?? throw new ArgumentNullException(nameof(execute));
        _canExecute = canExecute;
    }

    public bool CanExecute(object? parameter)
    {
        return _canExecute?.Invoke() ?? true;
    }

    public void Execute(object? parameter)
    {
        _execute();
    }

    public event EventHandler? CanExecuteChanged;

    public void RaiseCanExecuteChanged()
    {
        CanExecuteChanged?.Invoke(this, EventArgs.Empty);
    }
}

/// <summary>
/// 带参数的 RelayCommand
/// </summary>
public class RelayCommand<T> : ICommand
{
    private readonly Action<T> _execute;
    private readonly Predicate<T>? _canExecute;

    public RelayCommand(Action<T> execute, Predicate<T>? canExecute = null)
    {
        _execute = execute ?? throw new ArgumentNullException(nameof(execute));
        _canExecute = canExecute;
    }

    public bool CanExecute(object? parameter)
    {
        return _canExecute?.Invoke((T)parameter!) ?? true;
    }

    public void Execute(object? parameter)
    {
        _execute((T)parameter!);
    }

    public event EventHandler? CanExecuteChanged;

    public void RaiseCanExecuteChanged()
    {
        CanExecuteChanged?.Invoke(this, EventArgs.Empty);
    }
}