using System.Collections.ObjectModel;
using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Input;

using CommunityToolkit.Mvvm.Input;

using MpvNet.Windows.UI;
using MpvNet.Windows.WinForms;

namespace MpvNet.Windows.WPF.Controls;

public partial class CommandPaletteControl : UserControl
{
    public ICollectionView CollectionView { get; set; }
    public CollectionViewSource CollectionViewSource { get; }
    public ObservableCollection<CommandPaletteItem> Items { get; } = new ObservableCollection<CommandPaletteItem>();

    public CommandPaletteControl()
    {
        InitializeComponent();
        DataContext = this;
        CollectionViewSource = new CollectionViewSource() { Source = Items };
        CollectionView = CollectionViewSource.View;
        CollectionView.Filter = new Predicate<object>(item => Filter((CommandPaletteItem)item));
        MainListView.ItemsSource = CollectionView;

        SearchControl.SearchTextBox.PreviewKeyDown += SearchTextBox_PreviewKeyDown;
        SearchControl.SearchTextBox.TextChanged += SearchTextBox_TextChanged;
        SearchControl.HideClearButton = true;

        if (Environment.OSVersion.Version < new Version(10, 0))
            MainBorder.CornerRadius = new CornerRadius(0);
    }

    void SearchTextBox_TextChanged(object sender, TextChangedEventArgs e)
    {
        CollectionView.Refresh();
        SelectFirst();
    }

    void SearchTextBox_PreviewKeyDown(object sender, KeyEventArgs e)
    {
        switch (e.Key)
        {
            case Key.Up:
                {
                    int index = MainListView.SelectedIndex;
                    index -= 1;

                    if (index < 0)
                        index = 0;

                    MainListView.SelectedIndex = index;
                    MainListView.ScrollIntoView(MainListView.SelectedItem);
                }
                break;
            case Key.Down:
                {
                    int index = MainListView.SelectedIndex;

                    if (++index > MainListView.Items.Count - 1)
                        index = MainListView.Items.Count - 1;

                    MainListView.SelectedIndex = index;
                    MainListView.ScrollIntoView(MainListView.SelectedItem);
                }
                break;
        }
    }

    void MainListView_SizeChanged(object sender, SizeChangedEventArgs e) => AdjustHeight();

    void MainListView_MouseUp(object sender, MouseButtonEventArgs e) => ExecuteInternal();

    [RelayCommand]
    void Escape(object param) => MainForm.Instance?.HideCommandPalette();

    [RelayCommand]
    void Execute() => ExecuteInternal();

    void OnLoaded(object sender, RoutedEventArgs e) => Keyboard.Focus(SearchControl.SearchTextBox);

    public Theme Theme => Theme.Current!;

    bool Filter(CommandPaletteItem item)
    {
        string filter = SearchControl.SearchTextBox.Text.ToLower();

        if (item.Binding != null)
        {
            // TODO: CommandItem.Alias
            //if (item.CommandItem.Alias.ContainsEx(filter))
            //    return true;

            if (filter.Length == 1)
                return item.Binding.Input.ToLower()
                    .Replace("ctrl+", "")
                    .Replace("shift+", "")
                    .Replace("alt+", "") == filter.ToLower();
            
            if (item.Binding.Command.ToLower().Contains(filter))
                return true;
        }

        if (filter == "" || item.Text.ToLower().Contains(filter) ||
            item.SecondaryText.ToLower().Contains(filter))

            return true;

        return false;
    }

    public void SelectFirst()
    {
        if (MainListView.Items.Count > 0)
        {
            MainListView.SelectedIndex = 0;
            MainListView.ScrollIntoView(MainListView.SelectedItem);
        }
    }

    void ExecuteInternal()
    {
        if (MainListView.SelectedItem != null)
        {
            CommandPaletteItem? item = MainListView.SelectedItem as CommandPaletteItem;
            MainForm.Instance?.HideCommandPalette();
            item?.Action?.Invoke();
            //MainForm.Instance.Voodoo(); //TODO: Voodoo
        }
    }

    public void SetItems(IEnumerable<CommandPaletteItem> items)
    {
        Items.Clear();

        foreach (var i in items)
            Items.Add(i);
    }

    public void AdjustHeight()
    {
        double actualHeight = SearchControl.ActualHeight + MainListView.ActualHeight + 5 + 16;
        int dpi = MainForm.GetDpi(MainForm.Instance!.Handle);
        MainForm.Instance.CommandPaletteHost.Height = (int)(actualHeight / 96.0 * dpi);
    }
}