LehrerApp/LehrerApp.Desktop.Tests/PersonalizeWorksheetDialogViewModelTests.cs

using LehrerApp.Core.Models;
using LehrerApp.Desktop.ViewModels.Groups;
using LehrerApp.Templating;
using Xunit;

namespace LehrerApp.Desktop.Tests;

public sealed class PersonalizeWorksheetDialogViewModelTests : IDisposable
{
    private readonly string _directory = Path.Combine(Path.GetTempPath(), $"lehrerapp-worksheet-vm-tests-{Guid.NewGuid():N}");
    public PersonalizeWorksheetDialogViewModelTests() => Directory.CreateDirectory(_directory);

    [Fact]
    public void Generate_ErzeugtEinePdfJeAusgewaehltemSchueler()
    {
        var group = new LearningGroup { Name = "8a", SchoolYear = "2025/26" };
        var anna = new Student { FirstName = "Anna", LastName = "Adler" };
        var ben = new Student { FirstName = "Ben", LastName = "Bauer" };
        var vm = Build(group, [anna, ben], StoreWithTemplate());
        var output = Path.Combine(_directory, "output");

        vm.Generate(output);

        Assert.Equal(2, vm.Results.Count);
        Assert.All(vm.Results, r => Assert.True(r.Success));
        Assert.Equal(2, Directory.GetFiles(output, "*.pdf").Length);
    }

    [Fact]
    public void Generate_AbgewaehlterSchueler_WirdUebersprungen()
    {
        var group = new LearningGroup { Name = "8a", SchoolYear = "2025/26" };
        var anna = new Student { FirstName = "Anna", LastName = "Adler" };
        var ben = new Student { FirstName = "Ben", LastName = "Bauer" };
        var vm = Build(group, [anna, ben], StoreWithTemplate());
        vm.Students.Single(s => s.Model.Id == ben.Id).IsIncluded = false;
        var output = Path.Combine(_directory, "output");

        vm.Generate(output);

        Assert.Single(vm.Results);
        Assert.Equal(anna.FullName, vm.Results[0].StudentName);
    }

    [Fact]
    public void OhneVorlage_GenerateTutNichts()
    {
        var group = new LearningGroup { Name = "8a", SchoolYear = "2025/26" };
        var anna = new Student { FirstName = "Anna", LastName = "Adler" };
        var vm = Build(group, [anna], new WorksheetTemplateStore(new TemplateStore(Path.Combine(_directory, "empty-store"))));
        var output = Path.Combine(_directory, "output");

        vm.Generate(output);

        Assert.Empty(vm.Results);
    }

    private static PersonalizeWorksheetDialogViewModel Build(LearningGroup group, List<Student> students, WorksheetTemplateStore store) =>
        new(group, [.. students.Select(s => s.Id)], new FakeStudents(students), store, new QuestTemplateRenderer());

    private WorksheetTemplateStore StoreWithTemplate()
    {
        var source = Path.Combine(_directory, $"{Guid.NewGuid():N}.lavorlage");
        var manifest = new TemplateManifest
        {
            Id = $"arbeitsblatt-{Guid.NewGuid():N}", Name = "Arbeitsblatt",
            Placeholders = [new PlaceholderDefinition("Student.FirstName", PlaceholderType.Text)],
        };
        TemplatePackage.Create(source, manifest, "PAGE 210 297 mm\nTEXT 20 20 $Student.FirstName", new Dictionary<string, byte[]>());
        var store = new WorksheetTemplateStore(new TemplateStore(Path.Combine(_directory, $"store-{Guid.NewGuid():N}")));
        store.Store.Import(source);
        return store;
    }

    public void Dispose() { if (Directory.Exists(_directory)) Directory.Delete(_directory, true); }
}