LehrerApp/LehrerApp.Desktop/Views/Settings/SettingsView.axaml.cs

using Avalonia.Controls;
using Avalonia.Interactivity;
using Avalonia.Platform.Storage;
using LehrerApp.Desktop.ViewModels;
using LehrerApp.Desktop.ViewModels.Settings;
using LehrerApp.Desktop.Views.Shared;
using Microsoft.Extensions.DependencyInjection;

namespace LehrerApp.Desktop.Views.Settings;

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

    protected override void OnDataContextChanged(EventArgs e)
    {
        base.OnDataContextChanged(e);
        if (DataContext is SettingsViewModel vm)
        {
            vm.OnConfirmRestore = ShowRestoreConfirmDialog;
            vm.OnAppLockChanged = () => App.Services.GetRequiredService<AppLockViewModel>().ApplyConfig();
            vm.OnConfirmHardDelete = ShowHardDeleteConfirmDialog;
            vm.OnConfirmPairingRestore = ShowPairingRestoreConfirmDialog;
            vm.OnShowPairingError = ShowPairingErrorDialog;
            vm.OnSaveRecoveryFile = SaveRecoveryFile;
            vm.OnPickRecoveryFile = PickRecoveryFile;
            vm.OnConfirmRecoveryRestore = ShowRecoveryRestoreConfirmDialog;
            vm.OnThemeChanged = App.ApplyTheme;
        }
    }

    private async Task<bool> SaveRecoveryFile(string content)
    {
        var topLevel = TopLevel.GetTopLevel(this);
        if (topLevel is null) return false;

        var file = await topLevel.StorageProvider.SaveFilePickerAsync(new FilePickerSaveOptions
        {
            Title             = "Sync-Wiederherstellungsdatei speichern",
            SuggestedFileName = "LehrerApp-Sync-Wiederherstellung.json",
            FileTypeChoices   = [new FilePickerFileType("JSON-Dateien") { Patterns = ["*.json"] }],
        });
        if (file is null) return false;
        await File.WriteAllTextAsync(file.Path.LocalPath, content);
        return true;
    }

    private async Task<string?> PickRecoveryFile()
    {
        var topLevel = TopLevel.GetTopLevel(this);
        if (topLevel is null) return null;

        var files = await topLevel.StorageProvider.OpenFilePickerAsync(new FilePickerOpenOptions
        {
            Title = "Sync-Wiederherstellungsdatei auswählen",
            AllowMultiple = false,
            FileTypeFilter = [new FilePickerFileType("JSON-Dateien") { Patterns = ["*.json"] }],
        });
        return files.Count == 0 ? null : await File.ReadAllTextAsync(files[0].Path.LocalPath);
    }

    private async Task<bool> ShowRecoveryRestoreConfirmDialog()
    {
        var info = new ConfirmDialogInfo
        {
            Title       = "Sync-Schlüssel ersetzen?",
            Message     = "Der aktuelle Sync-Schlüssel dieses Geräts wird durch den aus der Datei ersetzt. " +
                          "Die App wird danach automatisch neu gestartet.",
            ConfirmText = "Ersetzen",
        };
        var dialog = new ConfirmDialog { DataContext = info };
        var owner = TopLevel.GetTopLevel(this) as Window;
        return owner is not null && await dialog.ShowDialog<bool>(owner);
    }

    private async Task<bool> ShowRestoreConfirmDialog(BackupListItem item)
    {
        var info = new ConfirmDialogInfo
        {
            Title       = "Backup wiederherstellen?",
            Message     = $"Die aktuelle Datenbank wird durch das Backup vom {item.Display} ersetzt. " +
                          "Die App wird danach automatisch neu gestartet.",
            ConfirmText = "Wiederherstellen",
        };
        var dialog = new ConfirmDialog { DataContext = info };
        var owner = TopLevel.GetTopLevel(this) as Window;
        return owner is not null && await dialog.ShowDialog<bool>(owner);
    }

    private async Task<bool> ShowHardDeleteConfirmDialog(ExpiredDocumentItem item)
    {
        var info = new ConfirmDialogInfo
        {
            Title       = "Eintrag endgültig löschen?",
            Message     = $"\"{item.Title}\" ({item.StudentName}) wird unwiderruflich gelöscht, nicht nur ausgeblendet.",
            ConfirmText = "Endgültig löschen",
        };
        var dialog = new ConfirmDialog { DataContext = info };
        var owner = TopLevel.GetTopLevel(this) as Window;
        return owner is not null && await dialog.ShowDialog<bool>(owner);
    }

    private async Task<bool> ShowPairingRestoreConfirmDialog()
    {
        var info = new ConfirmDialogInfo
        {
            Title       = "Gerät koppeln?",
            Message     = "Die lokale Datenbank auf diesem Gerät wird vollständig durch den Stand des anderen " +
                          "Geräts ersetzt. Der bisherige Stand wird automatisch als Backup gesichert. " +
                          "Die App wird danach automatisch neu gestartet.",
            ConfirmText = "Ersetzen",
        };
        var dialog = new ConfirmDialog { DataContext = info };
        var owner = TopLevel.GetTopLevel(this) as Window;
        return owner is not null && await dialog.ShowDialog<bool>(owner);
    }

    private async Task ShowPairingErrorDialog(string message)
    {
        var info = new ConfirmDialogInfo
        {
            Title       = "Kopplung fehlgeschlagen",
            Message     = $"{message}\n\nDie App wird jetzt neu gestartet (unveränderte Datenbank).",
            ConfirmText = "OK",
        };
        var dialog = new ConfirmDialog { DataContext = info };
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is not null) await dialog.ShowDialog<bool>(owner);
    }

    private async void OnImportClick(object? sender, RoutedEventArgs e)
    {
        var topLevel = TopLevel.GetTopLevel(this);
        if (topLevel is null || DataContext is not SettingsViewModel vm) return;

        var files = await topLevel.StorageProvider.OpenFilePickerAsync(new FilePickerOpenOptions
        {
            Title         = "Kompetenzkatalog importieren",
            AllowMultiple = false,
            FileTypeFilter = [new FilePickerFileType("JSON-Dateien") { Patterns = ["*.json"] }],
        });

        if (files.Count == 0) return;
        var json = await File.ReadAllTextAsync(files[0].Path.LocalPath);
        var preview = vm.PrepareCatalogImport(json);
        if (preview is null) return;

        var owner = topLevel as Window;
        if (owner is null) return;
        var dialog = new CompetencyCatalogImportDialog
        {
            DataContext = new CompetencyCatalogImportViewModel(vm, preview),
        };
        await dialog.ShowDialog<bool>(owner);
    }

    private async void OnExportClick(object? sender, RoutedEventArgs e)
    {
        var topLevel = TopLevel.GetTopLevel(this);
        if (topLevel is null || DataContext is not SettingsViewModel vm) return;

        var file = await topLevel.StorageProvider.SaveFilePickerAsync(new FilePickerSaveOptions
        {
            Title             = "Kompetenzkatalog exportieren",
            SuggestedFileName = $"Kompetenzkatalog_{vm.CatalogSubject?.Name}_{vm.CatalogGradeLevel}.json",
            FileTypeChoices   = [new FilePickerFileType("JSON-Dateien") { Patterns = ["*.json"] }],
        });

        if (file is null) return;
        var json = vm.ExportCatalog();
        await File.WriteAllTextAsync(file.Path.LocalPath, json);
    }

    private async void OnCopyCatalogClick(object? sender, RoutedEventArgs e)
    {
        if (DataContext is not SettingsViewModel { CatalogSubject: not null } vm) return;
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is null) return;

        var targetDialog = new CompetencyCatalogCopyTargetDialog
        {
            DataContext = new CompetencyCatalogCopyTargetViewModel(
                vm.CatalogSubject.Name, vm.CatalogGradeLevel),
        };
        var targetGradeLevel = await targetDialog.ShowDialog<int?>(owner);
        if (targetGradeLevel is null) return;

        var preview = vm.PrepareCatalogCopy(targetGradeLevel.Value);
        if (preview is null) return;
        var previewDialog = new CompetencyCatalogImportDialog
        {
            DataContext = new CompetencyCatalogImportViewModel(vm, preview, "Kopie prüfen"),
        };
        if (await previewDialog.ShowDialog<bool>(owner))
            vm.SetCatalogCopyStatus(targetGradeLevel.Value);
    }

    private async void OnEditGradingKeyTemplateClick(object? sender, RoutedEventArgs e)
    {
        if (sender is not Button { Tag: GradingKeyTemplateEditItem item }) return;
        var dialog = new GradingKeyTemplateDialog { DataContext = item };
        var owner = TopLevel.GetTopLevel(this) as Window;
        if (owner is not null) await dialog.ShowDialog(owner);
    }

    private async void OnImportLetterTemplateClick(object? sender, RoutedEventArgs e)
    {
        var topLevel = TopLevel.GetTopLevel(this);
        if (topLevel is null || DataContext is not SettingsViewModel vm) return;

        var files = await topLevel.StorageProvider.OpenFilePickerAsync(new FilePickerOpenOptions
        {
            Title = "Word-Briefvorlage importieren",
            AllowMultiple = false,
            FileTypeFilter = [new FilePickerFileType("Word-Dokumente") { Patterns = ["*.docx"] }],
        });
        if (files.Count > 0) vm.ImportLetterTemplate(files[0].Path.LocalPath);
    }

    private void OnOpenLetterTemplateClick(object? sender, RoutedEventArgs e)
    {
        if (sender is not Button { Tag: LetterTemplateListItem item }) return;
        var service = App.Services.GetRequiredService<LehrerApp.Core.Services.LetterTemplateService>();
        var path = service.GetTemplatePath(item.Model);
        if (!File.Exists(path)) return;
        System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(path) { UseShellExecute = true });
    }
}