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

namespace LehrerApp.Desktop.Tests;

public sealed class ExamDialogViewModelTests
{
    private static ExamDialogViewModel BuildViewModel(List<Exam> existingExams, string dateText,
        Exam? editingExam = null)
    {
        var vm = new ExamDialogViewModel(new FakeExams(existingExams), new FakeCompetencyDomains(),
            new FakeGradingKeyTemplates(), new GradingService(), Guid.NewGuid(), null, 9,
            GradingSystem.Grades1To6, "Chemie", isDifferentiated: false, editingExam, null);
        vm.DateText = dateText;
        return vm;
    }

    private static Exam MakeExam(DateOnly date) => new() { GroupId = Guid.NewGuid(), Title = "x", Date = date };

    [Fact]
    public void WeekLoadHint_WenigeKlausurenInDerWoche_BleibtLeer()
    {
        var monday = new DateOnly(2026, 3, 16);
        var existing = new List<Exam> { MakeExam(monday) };

        var vm = BuildViewModel(existing, monday.AddDays(1).ToString("dd.MM.yyyy"));

        Assert.Equal("", vm.WeekLoadHint);
    }

    [Fact]
    public void WeekLoadHint_DritteKlausurInDerWoche_ZeigtHinweis()
    {
        var monday = new DateOnly(2026, 3, 16);
        var existing = new List<Exam> { MakeExam(monday), MakeExam(monday.AddDays(1)) };

        var vm = BuildViewModel(existing, monday.AddDays(2).ToString("dd.MM.yyyy"));

        Assert.Contains("3 Klausuren", vm.WeekLoadHint);
    }

    [Fact]
    public void WeekLoadHint_BearbeiteteKlausurZaehltNichtDoppelt()
    {
        var monday = new DateOnly(2026, 3, 16);
        var editing = MakeExam(monday);
        var existing = new List<Exam> { editing, MakeExam(monday.AddDays(1)) };

        // Nur die eigene Klausur (editing) + eine weitere -> 2 insgesamt, kein Hinweis.
        var vm = BuildViewModel(existing, monday.ToString("dd.MM.yyyy"), editing);

        Assert.Equal("", vm.WeekLoadHint);
    }

    [Fact]
    public void WeekLoadHint_UngueltigesDatum_BleibtLeer()
    {
        var vm = BuildViewModel([], "keindatum");

        Assert.Equal("", vm.WeekLoadHint);
    }
}