using System.IO.Compression;
using LehrerApp.Core.Models;
using LehrerApp.Core.Services;
using LehrerApp.Desktop.ViewModels.Students;
using Xunit;

namespace LehrerApp.Desktop.Tests;

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

    public CreateLetterDialogViewModelTests() => Directory.CreateDirectory(_directory);

    [Fact]
    public void OhneVorlage_KannKeinenBriefErzeugen()
    {
        var student = StudentWithContact("Sehr geehrte Frau Muster,");

        var vm = Build(student, new LetterTemplateService(_directory));

        Assert.False(vm.CanGenerate);
        Assert.Contains(vm.Issues, i => i.Message.Contains("Vorlage", StringComparison.OrdinalIgnoreCase));
    }

    [Fact]
    public void VerwendeteBriefanredeFehlt_BlockiertErzeugung()
    {
        var service = ServiceWithTemplate("Letter.Salutation");
        var vm = Build(StudentWithContact(null), service);

        Assert.False(vm.CanGenerate);
        Assert.Contains(vm.Issues, i => i.Message.Contains("Briefanrede"));
    }

    [Fact]
    public void VollstaendigeDaten_ErzeugenEditierbareDocxKopie()
    {
        var service = ServiceWithTemplate("Letter.Salutation", "Student.FirstName", "CurrentDate");
        var vm = Build(StudentWithContact("Sehr geehrte Frau Muster,"), service);
        var output = Path.Combine(_directory, "Brief.docx");

        var generated = vm.Generate(output);

        Assert.True(generated);
        Assert.True(File.Exists(output));
        using var archive = ZipFile.OpenRead(output);
        using var reader = new StreamReader(archive.GetEntry("word/document.xml")!.Open());
        var xml = reader.ReadToEnd();
        Assert.Contains("Sehr geehrte Frau Muster,", xml);
        Assert.Contains("Lena", xml);
    }

    [Fact]
    public void KontaktBearbeiten_SpeichertExpliziteBriefanrede()
    {
        var vm = new ContactEditDialogViewModel(new Contact { Name = "Frau Muster" });
        vm.LetterSalutation = "Sehr geehrte Frau Muster,";

        vm.SaveCommand.Execute(null);

        Assert.Equal("Sehr geehrte Frau Muster,", vm.Result!.LetterSalutation);
    }

    private CreateLetterDialogViewModel Build(Student student, LetterTemplateService service) =>
        new(student, service, new FakeMemberships([]), new FakeGroups([]));

    private LetterTemplateService ServiceWithTemplate(params string[] tags)
    {
        var source = Path.Combine(_directory, $"{Guid.NewGuid():N}.docx");
        using (var archive = ZipFile.Open(source, ZipArchiveMode.Create))
        {
            var entry = archive.CreateEntry("word/document.xml");
            using var writer = new StreamWriter(entry.Open());
            var controls = string.Join("", tags.Select(tag =>
                $"<w:sdt><w:sdtPr><w:tag w:val=\"{tag}\"/></w:sdtPr><w:sdtContent>" +
                "<w:p><w:r><w:t>Platzhalter</w:t></w:r></w:p></w:sdtContent></w:sdt>"));
            writer.Write("<w:document xmlns:w=\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\">" +
                         $"<w:body>{controls}</w:body></w:document>");
        }
        var service = new LetterTemplateService(Path.Combine(_directory, $"service-{Guid.NewGuid():N}"));
        service.Import(source, "Elternbrief");
        return service;
    }

    private static Student StudentWithContact(string? salutation) => new()
    {
        FirstName = "Lena",
        LastName = "Beispiel",
        Contacts =
        [
            new Contact
            {
                Name = "Frau Muster",
                Relation = "Mutter",
                LetterSalutation = salutation,
                Street = "Hauptstraße 1",
                PostalCode = "12345",
                City = "Musterstadt",
            },
        ],
    };

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