using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using MaterialDesignThemes.Wpf;
using Tango.MachineStudio.Common.Notifications;
using Tango.MachineStudio.UI.Windows;
using System.Windows.Media;
using Tango.Core;
using System.Collections.ObjectModel;
using Tango.SharedUI;
using System.Collections.Concurrent;

namespace Tango.MachineStudio.UI.Notifications
{
    /// <summary>
    /// Represents the default Machine Studio <see cref="INotificationProvider">Notification Provider</see>.
    /// </summary>
    /// <seealso cref="Tango.Core.ExtendedObject" />
    /// <seealso cref="Tango.MachineStudio.Common.Notifications.INotificationProvider" />
    public class DefaultNotificationProvider : ExtendedObject, INotificationProvider
    {
        private int _message_count = 0;

        /// <summary>
        /// The view types
        /// </summary>
        private static List<Type> viewTypes;

        /// <summary>
        /// Gets the collection of active task items.
        /// </summary>
        public ObservableCollection<TaskItem> TaskItems { get; private set; }

        /// <summary>
        /// Gets the collection of active bar items.
        /// </summary>
        public ObservableCollection<BarItem> BarItems { get; private set; }

        /// <summary>
        /// Gets a value indicating whether there are any queued task items.
        /// </summary>
        public bool HasTaskItems
        {
            get { return TaskItems.Count > 0; }
        }

        /// <summary>
        /// The current task item
        /// </summary>
        private TaskItem _currentTaskItem;

        /// <summary>
        /// Gets the current displayed task item.
        /// </summary>
        public TaskItem CurrentTaskItem
        {
            get { return _currentTaskItem; }
            set { _currentTaskItem = value; RaisePropertyChangedAuto(); RaisePropertyChanged(nameof(HasTaskItems)); }
        }

        /// <summary>
        /// Initializes a new instance of the <see cref="DefaultNotificationProvider"/> class.
        /// </summary>
        public DefaultNotificationProvider()
        {
            TaskItems = new ObservableCollection<TaskItem>();
            BarItems = new ObservableCollection<BarItem>();
        }

        /// <summary>
        /// Display a message box.
        /// </summary>
        /// <param name="icon">The icon.</param>
        /// <param name="iconColor">Color of the icon.</param>
        /// <param name="message">The message.</param>
        /// <param name="hasCancel">if set to <c>true</c> displays the cancel button.</param>
        /// <returns></returns>
        public bool? ShowMessageBox(PackIconKind icon, Brush iconColor, string message, bool hasCancel)
        {
            MainWindow.Instance.shadowGrid.Visibility = Visibility.Visible;

            _message_count++;

            var result = new MessageBoxWindow()
            {
                Owner = Application.Current.MainWindow,
                Message = message,
                IconKind = icon,
                IconColor = iconColor,
                HasCancel = hasCancel

            }.ShowDialog();

            _message_count--;

            if (_message_count == 0)
            {
                MainWindow.Instance.shadowGrid.Visibility = Visibility.Hidden;
            }

            return result;
        }

        /// <summary>
        ///  Shows the specified view with the specified view model as it's data context.
        /// </summary>
        /// <typeparam name="VM">The type of the mm.</typeparam>
        /// <typeparam name="View">The type of the view.</typeparam>
        /// <param name="vm">The view model.</param>
        /// <param name="view">The view.</param>
        /// <param name="onAccept">The accept action.</param>
        /// <param name="onCancel">The cancel action.</param>
        public void ShowModalDialog<VM, View>(VM vm, View view, Action<VM> onAccept, Action onCancel) where View : FrameworkElement where VM : DialogViewVM
        {
            try
            {
                DialogWindow dialog = new DialogWindow();
                dialog.Owner = Application.Current.MainWindow;
                dialog.InnerContent = view;
                MainWindow.Instance.shadowGrid.Visibility = Visibility.Visible;
                view.Loaded += (x, y) =>
                {
                    try
                    {
                        VM context = vm;
                        dialog.DataContext = context;

                        Action onAcceptAction = null;
                        Action onCancelAction = null;

                        onAcceptAction = new Action(() =>
                        {
                            dialog.Close();
                            onAccept(context);
                            context.Accepted -= onAcceptAction;
                            context.Canceled -= onCancelAction;
                        });

                        onCancelAction = new Action(() =>
                        {
                            dialog.Close();

                            if (onCancel != null)
                            {
                                onCancel();
                            }

                            context.Canceled -= onCancelAction;
                            context.Accepted -= onAcceptAction;
                        });

                        context.Accepted += onAcceptAction;
                        context.Canceled += onCancelAction;

                        context.OnShow();
                    }
                    catch (Exception ex)
                    {
                        LogManager.Log(ex, $"Error display modal dialog. {typeof(VM).Name}");
                        onCancel?.Invoke();
                    }
                };

                dialog.ShowDialog();
            }
            catch (Exception ex)
            {
                LogManager.Log(ex, $"Error display modal dialog. {typeof(VM).Name}");
                onCancel?.Invoke();
            }
            finally
            {
                MainWindow.Instance.shadowGrid.Visibility = Visibility.Hidden;
            }
        }

        /// <summary>
        /// Creates a new instance of the specified View type and displays it as a modal dialog.
        /// </summary>
        /// <typeparam name="View">The type of the view.</typeparam>
        /// <typeparam name="VM">The type of the view model.</typeparam>
        /// <param name="onAccept">Accept button callback.</param>
        /// <param name="onCancel">Cancel button callback.</param>
        public void ShowModalDialog<View, VM>(Action<VM> onAccept, Action onCancel) where View : FrameworkElement where VM : DialogViewVM
        {
            try
            {
                var view = Activator.CreateInstance<View>();
                DialogWindow dialog = new DialogWindow();
                dialog.Owner = Application.Current.MainWindow;
                dialog.InnerContent = view;
                MainWindow.Instance.shadowGrid.Visibility = Visibility.Visible;
                view.Loaded += (x, y) =>
                {
                    try
                    {
                        VM context = view.DataContext as VM;
                        dialog.DataContext = context;

                        Action onAcceptAction = null;
                        Action onCancelAction = null;

                        onAcceptAction = new Action(() =>
                        {
                            dialog.Close();
                            onAccept(context);
                            context.Accepted -= onAcceptAction;
                            context.Canceled -= onCancelAction;
                        });

                        onCancelAction = new Action(() =>
                        {
                            dialog.Close();

                            if (onCancel != null)
                            {
                                onCancel();
                            }

                            context.Accepted -= onAcceptAction;
                            context.Canceled -= onCancelAction;
                        });

                        context.Accepted += onAcceptAction;
                        context.Canceled += onCancelAction;

                        context.OnShow();
                    }
                    catch (Exception ex)
                    {
                        LogManager.Log(ex, $"Error display modal dialog. {typeof(VM).Name}");
                        onCancel?.Invoke();
                    }
                };
                dialog.ShowDialog();
                MainWindow.Instance.shadowGrid.Visibility = Visibility.Hidden;
            }
            catch (Exception ex)
            {
                LogManager.Log(ex, $"Error display modal dialog. {typeof(VM).Name}");
                onCancel?.Invoke();
            }
            finally
            {
                MainWindow.Instance.shadowGrid.Visibility = Visibility.Hidden;
            }
        }

        /// <summary>
        ///  Shows the specified view with the specified view model as it's data context.
        /// </summary>
        /// <typeparam name="VM">The type of the mm.</typeparam>
        /// <typeparam name="View">The type of the view.</typeparam>
        /// <param name="vm">The view model.</param>
        /// <param name="view">The view.</param>
        /// <param name="onAccept">The accept action.</param>
        /// <param name="onCancel">The cancel action.</param>
        public void ShowModalDialog<VM, View>(VM vm, Action<VM> onAccept, Action onCancel) where View : FrameworkElement where VM : DialogViewVM
        {
            try
            {
                var view = Activator.CreateInstance<View>();
                DialogWindow dialog = new DialogWindow();
                dialog.Owner = Application.Current.MainWindow;
                dialog.InnerContent = view;
                MainWindow.Instance.shadowGrid.Visibility = Visibility.Visible;
                view.Loaded += (x, y) =>
                {
                    try
                    {
                        VM context = vm;
                        dialog.DataContext = context;

                        Action onAcceptAction = null;
                        Action onCancelAction = null;

                        onAcceptAction = new Action(() =>
                        {
                            dialog.Close();
                            onAccept(context);
                            context.Accepted -= onAcceptAction;
                            context.Canceled -= onCancelAction;
                        });

                        onCancelAction = new Action(() =>
                        {
                            dialog.Close();

                            if (onCancel != null)
                            {
                                onCancel();
                            }

                            context.Accepted -= onAcceptAction;
                            context.Canceled -= onCancelAction;
                        });

                        context.Accepted += onAcceptAction;
                        context.Canceled += onCancelAction;

                        context.OnShow();
                    }
                    catch (Exception ex)
                    {
                        LogManager.Log(ex, $"Error display modal dialog. {typeof(VM).Name}");
                        onCancel?.Invoke();
                    }
                };
                dialog.ShowDialog();
            }
            catch (Exception ex)
            {
                LogManager.Log(ex, $"Error display modal dialog. {typeof(VM).Name}");
                onCancel?.Invoke();
            }
            finally
            {
                MainWindow.Instance.shadowGrid.Visibility = Visibility.Hidden;
            }
        }

        /// <summary>
        /// Creates a new view by a naming convention of the specified view model type.
        /// </summary>
        /// <typeparam name="VM">The type of the view model.</typeparam>
        /// <param name="onAccept">Accept button callback.</param>
        /// <param name="onCancel">Cancel button callback.</param>
        /// <exception cref="NullReferenceException">Could not locate view " + viewName</exception>
        public void ShowModalDialog<VM>(Action<VM> onAccept, Action onCancel) where VM : DialogViewVM
        {
            try
            {
                String viewName = typeof(VM).Name.Replace("VM", "");

                if (viewTypes == null)
                {
                    viewTypes = AppDomain.CurrentDomain.GetAssemblies().Where(x => x.FullName.Contains("MachineStudio")).SelectMany(x => x.GetTypes()).ToList();
                }

                var viewType = viewTypes.SingleOrDefault(x => x.Name == viewName);

                if (viewType == null)
                {
                    throw new NullReferenceException("Could not locate view " + viewName);
                }

                var view = Activator.CreateInstance(viewType) as FrameworkElement;
                DialogWindow dialog = new DialogWindow();
                dialog.Owner = Application.Current.MainWindow;
                dialog.InnerContent = view;
                MainWindow.Instance.shadowGrid.Visibility = Visibility.Visible;
                view.Loaded += (x, y) =>
                {
                    try
                    {
                        VM context = view.DataContext as VM;
                        if (context == null)
                        {
                            context = Activator.CreateInstance<VM>();
                        }
                        dialog.DataContext = context;

                        Action onCancelAction = null;
                        Action onAcceptAction = null;

                        onAcceptAction = new Action(() =>
                        {
                            dialog.Close();
                            onAccept(context);

                            context.Canceled -= onCancelAction;
                            context.Accepted -= onAcceptAction;
                        });

                        onCancelAction = new Action(() =>
                        {
                            dialog.Close();

                            if (onCancel != null)
                            {
                                onCancel();
                            }

                            context.Canceled -= onCancelAction;
                            context.Accepted -= onAcceptAction;
                        });

                        context.Accepted += onAcceptAction;
                        context.Canceled += onCancelAction;

                        context.OnShow();
                    }
                    catch (Exception ex)
                    {
                        LogManager.Log(ex, $"Error display modal dialog. {typeof(VM).Name}");
                        onCancel?.Invoke();
                        return;
                    }
                };

                dialog.ShowDialog();
            }
            catch (Exception ex)
            {
                LogManager.Log(ex, $"Error display modal dialog. {typeof(VM).Name}");
                onCancel?.Invoke();
            }
            finally
            {
                MainWindow.Instance.shadowGrid.Visibility = Visibility.Hidden;
            }
        }

        /// <summary>
        /// Creates a new view by a naming convention of the specified view model type.
        /// </summary>
        /// <typeparam name="VM">The type of the view model.</typeparam>
        /// <param name="onAccept">Accept button callback.</param>
        public void ShowModalDialog<VM>(Action<VM> onAccept) where VM : DialogViewVM
        {
            ShowModalDialog<VM>(onAccept, null);
        }

        /// <summary>
        /// Shows an error message box.
        /// </summary>
        /// <param name="message">The message.</param>
        public void ShowError(string message)
        {
            ShowMessageBox(PackIconKind.AlertOctagon, (SolidColorBrush)Application.Current.Resources["RedBrush100"], message, false);
        }

        /// <summary>
        /// Shows an information message box.
        /// </summary>
        /// <param name="message">The message.</param>
        public void ShowInfo(string message)
        {
            ShowMessageBox(PackIconKind.CommentAlertOutline, (SolidColorBrush)Application.Current.Resources["Dialog.Foreground"], message, false);
        }

        /// <summary>
        /// Shows a question message box.
        /// </summary>
        /// <param name="message">The message.</param>
        /// <returns></returns>
        public bool ShowQuestion(string message)
        {
            return ShowMessageBox(PackIconKind.CommentQuestionOutline, (SolidColorBrush)Application.Current.Resources["Dialog.Foreground"], message, true).Value;
        }

        /// <summary>
        /// Shows warning message box.
        /// </summary>
        /// <param name="message">The message.</param>
        public void ShowWarning(string message)
        {
            ShowMessageBox(PackIconKind.AlertOutline, (SolidColorBrush)Application.Current.Resources["OrangeUploadBrush"], message, false);
        }

        /// <summary>
        /// Shows a question message box with an error icon.
        /// </summary>
        /// <param name="message">The message.</param>
        /// <returns></returns>
        public bool ShowErrorQuestion(string message)
        {
            return ShowMessageBox(PackIconKind.CommentAlertOutline, (SolidColorBrush)Application.Current.Resources["OrangeUploadBrush"], message, true).Value;
        }

        /// <summary>
        /// Pushes the specified task item to the queue.
        /// </summary>
        /// <param name="taskItem">The task item.</param>
        public void PushTaskItem(TaskItem taskItem)
        {
            InvokeUI(() =>
            {
                TaskItems.Add(taskItem);
                CurrentTaskItem = taskItem;
            });
        }

        /// <summary>
        /// Create and push a new task item from the specified message.
        /// </summary>
        /// <param name="message">The message.</param>
        /// <returns></returns>
        public TaskItem PushTaskItem(string message)
        {
            TaskItem item = new TaskItem(this);
            item.Message = message;
            PushTaskItem(item);
            return item;
        }

        /// <summary>
        /// Removed the specified task item from the queue.
        /// </summary>
        /// <param name="taskItem">The task item.</param>
        public void PopTaskItem(TaskItem taskItem)
        {
            Task.Delay(1000).ContinueWith((x) =>
            {
                InvokeUI(() =>
                {
                    TaskItems.Remove(taskItem);

                    if (TaskItems.Count > 0)
                    {
                        CurrentTaskItem = TaskItems.Last();
                    }

                    RaisePropertyChanged(nameof(HasTaskItems));
                });
            });
        }

        /// <summary>
        /// Pushes the specified bar item.
        /// </summary>
        /// <param name="barItem">The bar item.</param>
        /// <returns></returns>
        public BarItem PushBarItem(BarItem barItem)
        {
            BarItems.Add(barItem);
            return barItem;
        }

        /// <summary>
        /// Creates and push a new bar item from the specified framework element.
        /// </summary>
        /// <param name="element">The element.</param>
        /// <returns></returns>
        public BarItem PushBarItem(FrameworkElement element)
        {
            BarItem item = new BarItem(this);
            item.Element = element;
            PushBarItem(item);
            return item;
        }

        /// <summary>
        /// Removed the specified bar item.
        /// </summary>
        /// <param name="barItem">The bar item.</param>
        public void PopBarItem(BarItem barItem)
        {
            BarItems.Remove(barItem);
        }

        /// <summary>
        /// Shows a dialog with a text input field and returns the response.
        /// </summary>
        /// <param name="message">The message.</param>
        /// <param name="hint">Text field hint.</param>
        /// <param name="defaultResponse">Optional default response.</param>
        /// <returns></returns>
        public string ShowTextInput(string message, string hint, string defaultResponse = null)
        {
            MainWindow.Instance.shadowGrid.Visibility = Visibility.Visible;

            TextInputBoxWindow dlg = new TextInputBoxWindow()
            {
                Owner = Application.Current.MainWindow,
                Message = message,
                IconKind = PackIconKind.Pencil,
                IconColor = (SolidColorBrush)Application.Current.Resources["DimGrayBrush"],
                Hint = hint,
                Response = defaultResponse
            };

            var result = dlg.ShowDialog();

            MainWindow.Instance.shadowGrid.Visibility = Visibility.Hidden;
            return (result.Value ? dlg.Response : null);
        }
    }
}