LehrerApp/LehrerApp.Desktop/Views/Groups/GradeOverviewTabView.axaml.cs

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

namespace LehrerApp.Desktop.Views.Groups;

public partial class GradeOverviewTabView : UserControl
{
    private GradeOverviewTabViewModel? _vm;

    public GradeOverviewTabView() => InitializeComponent();

    protected override void OnDataContextChanged(EventArgs e)
    {
        base.OnDataContextChanged(e);

        if (DataContext is GradeOverviewTabViewModel vm)
        {
            _vm = vm;
            vm.OnManageStudentGrades = ShowStudentGradesDialog;
            vm.OnCollectiveGrade = ShowCollectiveGradeDialog;
            vm.OnReportGrades = ShowReportGradesDialog;
            vm.OnInterimGrades = async studentId =>
            {
                if (TopLevel.GetTopLevel(this) is Window owner) await ShowInterimRun(owner, studentId);
            };
            vm.OnShowPerformanceOverview = ShowPerformanceOverviewDialog;
            vm.PropertyChanged += (_, pe) =>
            {
                if (pe.PropertyName == nameof(GradeOverviewTabViewModel.RebuildColumnsSignal))
                    BuildColumns();
            };
            BuildColumns();
        }
    }

    private async Task ShowStudentGradesDialog(GradeOverviewRow row)
    {
        var dialogVm = new StudentGradesDialogViewModel(
            App.Services.GetRequiredService<IGradeRepository>(),
            row.StudentId, _vm!.GroupId, row.Name);

        var dialog = new StudentGradesDialog { DataContext = dialogVm };
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is not null) await dialog.ShowDialog(owner);
    }

    private async Task ShowCollectiveGradeDialog()
    {
        var dialogVm = new CollectiveGradeDialogViewModel(
            App.Services.GetRequiredService<IGradeRepository>(),
            App.Services.GetRequiredService<IStudentRepository>(),
            App.Services.GetRequiredService<IGroupMembershipRepository>(),
            _vm!.GroupId);

        var dialog = new CollectiveGradeDialog { DataContext = dialogVm };
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is not null) await dialog.ShowDialog(owner);
    }

    private async Task ShowReportGradesDialog()
    {
        var dialogVm = new ReportGradeDialogViewModel(
            App.Services.GetRequiredService<IGradeRepository>(),
            App.Services.GetRequiredService<IExamRepository>(),
            App.Services.GetRequiredService<IExamResultRepository>(),
            App.Services.GetRequiredService<IStudentRepository>(),
            App.Services.GetRequiredService<IGroupMembershipRepository>(),
            App.Services.GetRequiredService<IGradingSchemeRepository>(),
            App.Services.GetRequiredService<IReportGradeRepository>(),
            App.Services.GetRequiredService<IParticipationSessionRepository>(),
            App.Services.GetRequiredService<IParticipationRepository>(),
            App.Services.GetRequiredService<AttendanceBalanceService>(),
            App.Services.GetRequiredService<GradingService>(),
            _vm!.GroupId, _vm.GroupType, _vm.GradingSystem, _vm.GroupLabel, _vm.SchoolYear);

        var dialog = new ReportGradeDialog { DataContext = dialogVm, OnOpenAssistant = owner => ShowReportGradeAssistant(owner) };
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is not null) await dialog.ShowDialog(owner);
    }

    private async Task ShowReportGradeAssistant(Window owner, InterimRunOptions? interim = null)
    {
        var dialogVm = new ReportGradeAssistantViewModel(
            App.Services.GetRequiredService<IGradeRepository>(),
            App.Services.GetRequiredService<IExamRepository>(),
            App.Services.GetRequiredService<IExamResultRepository>(),
            App.Services.GetRequiredService<IStudentRepository>(),
            App.Services.GetRequiredService<IGroupMembershipRepository>(),
            App.Services.GetRequiredService<IGradingSchemeRepository>(),
            App.Services.GetRequiredService<IReportGradeRepository>(),
            App.Services.GetRequiredService<IParticipationSessionRepository>(),
            App.Services.GetRequiredService<IParticipationRepository>(),
            App.Services.GetRequiredService<IParticipationAspectRepository>(),
            App.Services.GetRequiredService<IParticipationSectionRepository>(),
            App.Services.GetRequiredService<IInterimGradeRepository>(),
            App.Services.GetRequiredService<AttendanceBalanceService>(),
            App.Services.GetRequiredService<GradingService>(),
            _vm!.GroupId, _vm.GroupType, _vm.GradingSystem, _vm.GroupLabel, _vm.SchoolYear,
            App.Services.GetRequiredService<IGroupRepository>().GetById(_vm.GroupId)?.GradeLevel ?? 0,
            interim: interim);

        var dialog = new ReportGradeAssistantDialog { DataContext = dialogVm };
        dialogVm.OnStartInterim = studentId => ShowInterimRun(dialog, studentId);
        await dialog.ShowDialog(owner);
    }

    /// Zwischenstand: erst Stichtag, Anlass und Schüler festlegen, dann geht der Assistent genau
    /// diese Schüler durch.
    private async Task ShowInterimRun(Window owner, Guid? preselectedStudentId)
    {
        var dialogVm = new InterimRunDialogViewModel(
            App.Services.GetRequiredService<IGradeRepository>(),
            App.Services.GetRequiredService<IExamRepository>(),
            App.Services.GetRequiredService<IExamResultRepository>(),
            App.Services.GetRequiredService<IStudentRepository>(),
            App.Services.GetRequiredService<IGroupMembershipRepository>(),
            App.Services.GetRequiredService<IGradingSchemeRepository>(),
            App.Services.GetRequiredService<IReportGradeRepository>(),
            App.Services.GetRequiredService<IParticipationSessionRepository>(),
            App.Services.GetRequiredService<IParticipationRepository>(),
            App.Services.GetRequiredService<IParticipationAspectRepository>(),
            App.Services.GetRequiredService<IParticipationSectionRepository>(),
            App.Services.GetRequiredService<IInterimGradeRepository>(),
            App.Services.GetRequiredService<GradingService>(),
            _vm!.GroupId, _vm.GroupType, _vm.GradingSystem, _vm.GroupLabel, _vm.SchoolYear,
            preselectedStudentId);

        var dialog = new InterimRunDialog { DataContext = dialogVm };
        if (await dialog.ShowDialog<bool>(owner) && dialogVm.Result is { } run)
            await ShowReportGradeAssistant(owner, run);
    }

    private async Task ShowPerformanceOverviewDialog(GradeOverviewRow row)
    {
        var dialogVm = new StudentPerformanceOverviewViewModel(
            App.Services.GetRequiredService<IGradeRepository>(),
            App.Services.GetRequiredService<IExamRepository>(),
            App.Services.GetRequiredService<IExamResultRepository>(),
            App.Services.GetRequiredService<IGroupMembershipRepository>(),
            App.Services.GetRequiredService<IGradingSchemeRepository>(),
            App.Services.GetRequiredService<GradingService>(),
            _vm!.GroupId, row.StudentId, _vm.GroupType, _vm.GradingSystem, row.Name, _vm.GroupLabel, _vm.SchoolYear);

        var dialog = new StudentPerformanceOverviewDialog { DataContext = dialogVm };
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is not null) await dialog.ShowDialog(owner);
    }

    private async void OnExportPdfClick(object? sender, RoutedEventArgs e)
    {
        var topLevel = TopLevel.GetTopLevel(this);
        if (topLevel is null || _vm is null) return;

        // Vorläufige Zwischenstände gehören nicht in die gedruckte Notenliste. Ihre Spalten
        // stehen immer am Ende, die Zellen lassen sich also einfach abschneiden.
        var printed = _vm.Columns.Where(c => !c.IsInterim).ToList();
        var data = new GradeListPrintData(
            _vm.GroupLabel, _vm.SchoolYear, _vm.SelectedPeriod.Label,
            printed.Select(c => c.Header).ToList(),
            _vm.Rows.Select(r => new GradeListPrintRow(r.Name, r.Cells.Take(printed.Count).ToList(), r.TotalDisplay)).ToList());
        var pdf = App.Services.GetRequiredService<PdfExportService>().BuildGradeListPdf(data);

        await App.Services.GetRequiredService<ExportService>().SaveAsync(topLevel.StorageProvider,
            ExportFile.Pdf("Notenliste als PDF speichern",
                $"Notenliste_{_vm.GroupLabel}_{_vm.SchoolYear.Replace('/', '-')}", pdf));
    }

    private void BuildColumns()
    {
        var grid = this.FindControl<DataGrid>("GradesGrid");
        if (grid is null || _vm is null) return;

        grid.Columns.Clear();
        grid.Columns.Add(new DataGridTextColumn
        {
            Header  = "Schüler",
            Binding = new Binding("Name"),
            Width   = new DataGridLength(160, DataGridLengthUnitType.Pixel),
        });

        foreach (var (col, i) in _vm.Columns.Select((c, i) => (c, i)))
        {
            var idx = i;
            var column = new DataGridTextColumn
            {
                Header  = col.Header,
                Binding = new Binding($"Cells[{idx}]"),
                Width   = new DataGridLength(120, DataGridLengthUnitType.Pixel),
            };
            // Zwischenstände sind vorläufig — grau, damit sie nicht wie eingetragene Noten wirken.
            if (col.IsInterim) column.Foreground = Avalonia.Media.Brushes.Gray;
            grid.Columns.Add(column);
        }

        grid.Columns.Add(new DataGridTextColumn
        {
            Header  = "Gesamt",
            Binding = new Binding("TotalDisplay"),
            Width   = new DataGridLength(80, DataGridLengthUnitType.Pixel),
        });
    }
}