using Avalonia.Controls;
using Avalonia.Interactivity;
using LehrerApp.Core.Interfaces;
using LehrerApp.Core.Models;
using LehrerApp.Core.Services;
using LehrerApp.Desktop.ViewModels;
using LehrerApp.Desktop.ViewModels.Planning;
using LehrerApp.Desktop.ViewModels.Groups;
using LehrerApp.Desktop.Views.Groups;
using LehrerApp.Desktop.Services;
using Microsoft.Extensions.DependencyInjection;

namespace LehrerApp.Desktop.Views.Planning;

public partial class TimetableView : UserControl
{
    public TimetableView() => InitializeComponent();

    protected override void OnDataContextChanged(EventArgs e)
    {
        base.OnDataContextChanged(e);
        if (DataContext is TimetableViewModel vm)
        {
            vm.OnEditSlot = ShowSlotDialog;
            vm.OnAddSubstitution = ShowSubstitutionDialog;
            vm.OnImportWebUntisTimetable = ShowWebUntisTimetableDialog;
            vm.OnOpenLessonViewer = ShowLessonViewerDialog;
            vm.OnOpenTeachingMode = ShowTeachingMode;
        }
    }

    /// Nutzer-Feedback (zweite Runde — die erste Fassung hatte das Problem an der falschen
    /// Stelle gelöst, in der "Heute"-Tagesliste statt im Wochenraster): im Wochenraster oben
    /// führt ein Klick auf eine Stunden-Kachel bislang entweder in den Planungsviewer oder zur
    /// Einheitenplanung — je nachdem, ob schon eine Lesson existiert, ohne dass das von außen
    /// erkennbar wäre. Popup-Menü (MenuFlyout, kein ComboBox mehr) mit allen vier Zielen als
    /// Alternative zum Direktklick, siehe <see cref="TimetableViewModel.OpenWeekCellCommand"/>
    /// für den "einheitlicheren" Standard-Klick (Unterrichtsansicht bei laufender Stunde, sonst
    /// Planungsviewer, sonst Einheitenplanung). MenuItem.Click statt Command-Binding: ein
    /// $parent[ItemsControl]-Vorfahrenpfad (wie beim Zeilen-Button) funktioniert innerhalb eines
    /// Flyouts nicht zuverlässig, weil dessen Popup nicht im normalen visuellen Baum hängt (siehe
    /// TODO.md-Nachtrag zum Klassenlehrer-Bereich) — DataContext-Vererbung (kein Pfad-Suchen,
    /// nur der normale Eltern-Wert) funktioniert dort aber sehr wohl, deshalb liest der Handler
    /// die Zelle über <c>((MenuItem)sender).DataContext</c> statt über eine Binding.
    private async void OnWeekCellMenuItemClick(object? sender, RoutedEventArgs e)
    {
        if (sender is not MenuItem { Tag: TimetableLessonDestination destination } menuItem) return;
        if (menuItem.DataContext is not WeekCellItem cell) return;
        if (DataContext is not TimetableViewModel vm) return;

        switch (destination)
        {
            case TimetableLessonDestination.TeachingMode:
                if (cell.Lesson is { } teachLesson && vm.OnOpenTeachingMode is not null)
                    await vm.OnOpenTeachingMode(teachLesson);
                break;
            case TimetableLessonDestination.Viewer:
                if (cell.Lesson is { } viewLesson && vm.OnOpenLessonViewer is not null)
                    await vm.OnOpenLessonViewer(viewLesson);
                break;
            case TimetableLessonDestination.Planning:
                if (cell.GroupId != Guid.Empty)
                    App.Services.GetRequiredService<MainWindowViewModel>().NavigateToGroupDetail(cell.GroupId, 6);
                break;
            case TimetableLessonDestination.SeatingPlan:
                if (cell.GroupId != Guid.Empty)
                    App.Services.GetRequiredService<MainWindowViewModel>().NavigateToGroupDetail(cell.GroupId, 2);
                break;
        }
    }

    private async Task ShowWebUntisTimetableDialog()
    {
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is null) return;
        var vm = new WebUntisTimetableImportViewModel(
            App.Services.GetRequiredService<WebUntisIntegrationService>(),
            App.Services.GetRequiredService<WebUntisSettingsService>(),
            App.Services.GetRequiredService<ITimetableSlotRepository>(),
            App.Services.GetRequiredService<IGroupRepository>());
        var dialog = new WebUntisTimetableImportDialog { DataContext = vm };
        vm.OnCreateGroup = dialog.CreateGroupAsync;
        await vm.InitializeAsync();
        await dialog.ShowDialog<bool>(owner);
    }

    private async Task ShowTeachingMode(Lesson lesson)
    {
        var owner = TopLevel.GetTopLevel(this) as Window;
        var group = App.Services.GetRequiredService<IGroupRepository>().GetById(lesson.GroupId);
        if (owner is null || group is null) return;

        var teachingModeVm = new TeachingModeViewModel(lesson, group,
            App.Services.GetRequiredService<IAlternativeLessonPathRepository>(),
            App.Services.GetRequiredService<ILessonRepository>(),
            App.Services.GetRequiredService<SeatingPlanTabViewModel>(),
            App.Services.GetRequiredService<ParticipationTabViewModel>());
        var window = new TeachingModeWindow { DataContext = teachingModeVm };
        await window.ShowDialog(owner);
    }

    private async Task ShowLessonViewerDialog(Lesson lesson)
    {
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is null) return;

        var viewerVm = new LessonViewerViewModel(lesson,
            App.Services.GetRequiredService<IAlternativeLessonPathRepository>());
        var dialog = new LessonViewerDialog { DataContext = viewerVm };
        await dialog.ShowDialog(owner);
    }

    private async Task ShowSlotDialog(TimetableCellItem cell)
    {
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is null || cell.Weekday is null) return;

        var vm = new TimetableSlotDialogViewModel(
            App.Services.GetRequiredService<ITimetableSlotRepository>(),
            App.Services.GetRequiredService<IGroupRepository>(),
            App.Services.GetRequiredService<ISubjectRepository>(),
            App.Services.GetRequiredService<SchoolYearService>(),
            cell.Weekday.Value, cell.PeriodNumber, cell.Slot);

        var dialog = new TimetableSlotDialog { DataContext = vm };
        await dialog.ShowDialog(owner);
    }

    private async Task ShowSubstitutionDialog()
    {
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is null) return;

        var vm = new SubstitutionEntryDialogViewModel(
            App.Services.GetRequiredService<ISubstitutionEntryRepository>(),
            App.Services.GetRequiredService<IGroupRepository>(),
            App.Services.GetRequiredService<IUnitRepository>(),
            App.Services.GetRequiredService<ILessonRepository>());

        var dialog = new SubstitutionEntryDialog { DataContext = vm };
        await dialog.ShowDialog(owner);
    }
}