using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Input;
namespace BPASmartClient.SCADAControl.Converters
{
    public class RelayCommandSimple :ICommand, IDisposable
    {
        private Action _executeCallback;
        private Func<bool> _canExecute;

        public RelayCommandSimple(Action execute)
        {
            _executeCallback = execute;
        }

        public RelayCommandSimple(Action execute,Func<bool> canExecute)
            : this(execute)
        {
            _canExecute = canExecute;
        }

        public bool CanExecute(object parameter)
        {
            if (_canExecute == null)
                return true;
            return _canExecute();
        }

        public void Execute(object parameter)
        {
            _executeCallback();
        }

        public void Dispose()
        {
            _executeCallback = null;
            _canExecute = null;
        }

        public event EventHandler CanExecuteChanged
        {
            add
            {
                if (this._canExecute != null)
                {
                    CommandManager.RequerySuggested += value;
                }
            }
            remove
            {
                if (this._canExecute != null)
                {
                    CommandManager.RequerySuggested -= value;
                }
            }
        }
    }

    public class RelayCommandSimple<TParam> :ICommand
    {
        private Action<TParam> _executeCallback;
        private Func<TParam,bool> _canExecute;

        public RelayCommandSimple(Action<TParam> execute)
        {
            if (execute == null)
                throw new ArgumentNullException("execute");

            _executeCallback = execute;
        }

        public RelayCommandSimple(Action<TParam> execute,Func<TParam,bool> canExecute)
            : this(execute)
        {
            _canExecute = canExecute;
        }

        public bool CanExecute(object parameter)
        {
            if (_canExecute == null)
                return true;

            if (parameter != null && parameter is TParam)
            {
                return _canExecute((TParam)parameter);
            }
            return true;
        }

        public void Execute(object parameter)
        {
            if (parameter != null && parameter is TParam)
            {
                _executeCallback((TParam)parameter);
            }
        }

        public event EventHandler CanExecuteChanged
        {
            add
            {
                if (this._canExecute != null)
                {
                    CommandManager.RequerySuggested += value;
                }
            }
            remove
            {
                if (this._canExecute != null)
                {
                    CommandManager.RequerySuggested -= value;
                }
            }
        }
    }


    public class RelayCommandSimpleNull<T> :ICommand
    {
        private Action<T> _executeCallback;
        private Func<T,bool> _canExecute;

        public RelayCommandSimpleNull(Action<T> execute)
        {
            if (execute == null)
                throw new ArgumentNullException("execute");

            _executeCallback = execute;
        }

        public RelayCommandSimpleNull(Action<T> execute,Func<T,bool> canExecute)
            : this(execute)
        {
            _canExecute = canExecute;
        }

        public bool CanExecute(object parameter)
        {
            if (_canExecute == null)
                return true;


            return _canExecute((T)parameter);

        }

        public void Execute(object parameter)
        {
            _executeCallback((T)parameter);
        }

        public event EventHandler CanExecuteChanged
        {
            add
            {
                if (this._canExecute != null)
                {
                    CommandManager.RequerySuggested += value;
                }
            }
            remove
            {
                if (this._canExecute != null)
                {
                    CommandManager.RequerySuggested -= value;
                }
            }
        }
    }
}