using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using DTS.Common.Controls;
using DTS.Common.Events;
using Microsoft.Practices.Prism.Events;
using Microsoft.Practices.ServiceLocation;

namespace DTS.Common.Behaviors
{
    public class TextBoxPasteBehavior
    {
        public static readonly DependencyProperty PasteCommandProperty =
            DependencyProperty.RegisterAttached(
                "PasteCommand",
                typeof(ICommand),
                typeof(TextBoxPasteBehavior),
                new FrameworkPropertyMetadata(PasteCommandChanged)
            );

        public static ICommand GetPasteCommand(DependencyObject target)
        {
            return (ICommand)target.GetValue(PasteCommandProperty);
        }

        public static void SetPasteCommand(DependencyObject target, ICommand value)
        {
            target.SetValue(PasteCommandProperty, value);
        }

        private static void PasteCommandChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
        {
            TextBox textBox = sender as TextBox;
            if (null == textBox && sender is ChannelCodeBuilder ccb)
            {
                textBox = ccb.MainEditBox;
            }
            else if (null == textBox && sender is ChannelNameBuilder cnb)
            {
                textBox = cnb.MainEditBox;
            }
            var newValue = (ICommand)e.NewValue;
            textBox.RemoveHandler(CommandManager.ExecutedEvent, new RoutedEventHandler(CommandExecuted));
            if (newValue != null)
            {
                textBox.AddHandler(CommandManager.ExecutedEvent, new RoutedEventHandler(CommandExecuted), true);
            }
        }

        private static void CommandExecuted(object sender, RoutedEventArgs e)
        {
            if( !(e is ExecutedRoutedEventArgs eArgs)) { return; }

            if (eArgs.Command != ApplicationCommands.Paste)
            {
                if (eArgs.Command is RoutedUICommand secureUICommand)
                {
                    if( secureUICommand.Name != "Paste") { return; }
                }
                else{ return; }
            }
            TextBox textBox = sender as TextBox;
            if (null == sender && sender is ChannelCodeBuilder ccb)
            {
                textBox = ccb.MainEditBox;
            }
            else if (null == sender && sender is ChannelNameBuilder cnb)
            {
                textBox = cnb.MainEditBox;
            }
            
            var command = GetPasteCommand(textBox);

            try
            {
                var text = Clipboard.GetText();
                var lines = text.Split(new[] {Environment.NewLine}, StringSplitOptions.None);

                if (command.CanExecute(null))
                    command.Execute(textBox);
                e.Handled = true;
            }
            catch (Exception ex)
            {
                var eventAggregator = ServiceLocator.Current.GetInstance<IEventAggregator>();
                eventAggregator.GetEvent<PageErrorEvent>().Publish(new PageErrorArg(new[] {ex.Message}, null));
            }
        }
    }
}