using System.Net;
using System.Net.Http.Headers;
using System.Net.Http.Json;
using BigRegister.Api.Contracts;
using Microsoft.AspNetCore.Mvc.Testing;

namespace BigRegister.Tests;

/// WP-65 (read side): one aanvraag's case-treatment detail, gated by the same medewerker
/// capability (`CanBeoordelen`, WP-62) as the werkvoorraad list (WP-64).
public class BeoordelingTests(TestWebApplicationFactory factory) : IClassFixture<TestWebApplicationFactory>
{
  private readonly HttpClient _client = factory.CreateClient();

  private static HttpRequestMessage AsBehandelaar(HttpMethod method, string path)
  {
    var req = new HttpRequestMessage(method, path);
    req.Headers.Add("X-Medewerker", "medewerker-1");
    return req;
  }

  private static MultipartFormDataContent UploadForm(string localId, string categoryId, string fileName)
  {
    var content = new MultipartFormDataContent();
    var file = new ByteArrayContent(new byte[] { 1, 2, 3 });
    file.Headers.ContentType = new MediaTypeHeaderValue("application/pdf");
    content.Add(file, "file", fileName);
    content.Add(new StringContent(categoryId), "categoryId");
    content.Add(new StringContent(localId), "localId");
    content.Add(new StringContent("registratie"), "wizardId");
    return content;
  }

  /// A manual (never auto-approved) case with one linked document, so it stays
  /// InBehandeling/decidable regardless of test timing (the 8s auto-approval window
  /// would otherwise make a duo-registratie/herregistratie fixture flaky).
  private async Task<(ApplicationDetailDto App, string DocumentId)> CreateManualCaseWithDocument()
  {
    var created = await _client.PostAsJsonAsync("/api/v1/applications", new { type = "registratie" });
    var a = (await created.Content.ReadFromJsonAsync<ApplicationDetailDto>())!;

    var localId = Guid.NewGuid().ToString();
    var upload = await _client.PostAsync("/api/v1/uploads", UploadForm(localId, "diploma", "diploma.pdf"));
    upload.EnsureSuccessStatusCode();
    var doc = (await upload.Content.ReadFromJsonAsync<UploadResponse>())!;

    var submit = await _client.PostAsJsonAsync($"/api/v1/applications/{a.Id}/submit", new
    {
      diplomaHerkomst = "handmatig",
      documents = new[] { new { categoryId = "diploma", channel = "digital", documentId = doc.DocumentId } },
    });
    submit.EnsureSuccessStatusCode();
    return (a, doc.DocumentId!);
  }

  private Task DeleteAsAdmin(string id) => _client.SendAsync(new HttpRequestMessage(HttpMethod.Delete, $"/api/v1/admin/cases/{id}")
  {
    Headers = { { "X-Role", "admin" } },
  });

  [Fact]
  public async Task Detail_shows_status_documents_and_a_masked_owner()
  {
    var (a, documentId) = await CreateManualCaseWithDocument();
    try
    {
      var res = await _client.SendAsync(AsBehandelaar(HttpMethod.Get, $"/api/v1/beoordeling/{a.Id}"));
      res.EnsureSuccessStatusCode();
      var view = (await res.Content.ReadFromJsonAsync<BeoordelingViewDto>())!;

      Assert.Equal("InBehandeling", view.Aanvraag.Status.Tag);
      Assert.Single(view.Documenten);
      Assert.Equal(documentId, view.Documenten[0].DocumentId);
      Assert.Equal("diploma", view.Documenten[0].CategoryId);
      Assert.True(view.Decisions.CanBesluiten);
      // masked: not empty, but not the full 9-digit BSN either
      var owner = view.Aanvraag.Owner!;
      Assert.NotEmpty(owner);
      Assert.Contains('*', owner);
    }
    finally
    {
      await DeleteAsAdmin(a.Id);
    }
  }

  [Fact]
  public async Task Concept_and_unknown_id_are_not_found()
  {
    var created = await _client.PostAsJsonAsync("/api/v1/applications", new { type = "registratie" });
    var concept = (await created.Content.ReadFromJsonAsync<ApplicationDetailDto>())!;
    try
    {
      var conceptRes = await _client.SendAsync(AsBehandelaar(HttpMethod.Get, $"/api/v1/beoordeling/{concept.Id}"));
      Assert.Equal(HttpStatusCode.NotFound, conceptRes.StatusCode);

      var unknownRes = await _client.SendAsync(AsBehandelaar(HttpMethod.Get, "/api/v1/beoordeling/does-not-exist"));
      Assert.Equal(HttpStatusCode.NotFound, unknownRes.StatusCode);
    }
    finally
    {
      await _client.DeleteAsync($"/api/v1/applications/{concept.Id}");
    }
  }

  [Fact]
  public async Task Zorgverlener_is_forbidden_even_with_admin_role()
  {
    var (a, _) = await CreateManualCaseWithDocument();
    try
    {
      var req = new HttpRequestMessage(HttpMethod.Get, $"/api/v1/beoordeling/{a.Id}");
      req.Headers.Add("X-Role", "admin"); // admin role, but no X-Medewerker — still a zorgverlener
      Assert.Equal(HttpStatusCode.Forbidden, (await _client.SendAsync(req)).StatusCode);
    }
    finally
    {
      await DeleteAsAdmin(a.Id);
    }
  }

  [Fact]
  public async Task Medewerker_without_behandelaar_rol_is_forbidden()
  {
    var req = new HttpRequestMessage(HttpMethod.Get, "/api/v1/beoordeling/anything");
    req.Headers.Add("X-Medewerker", "medewerker-2");
    req.Headers.Add("X-Rollen", "geen");
    Assert.Equal(HttpStatusCode.Forbidden, (await _client.SendAsync(req)).StatusCode);
  }

  private Task<HttpResponseMessage> PostBesluit(string id, object body)
  {
    var req = AsBehandelaar(HttpMethod.Post, $"/api/v1/beoordeling/{id}/besluit");
    req.Content = JsonContent.Create(body);
    return _client.SendAsync(req);
  }

  [Fact]
  public async Task Goedkeuren_advances_status_to_Goedgekeurd()
  {
    var (a, _) = await CreateManualCaseWithDocument();
    try
    {
      var res = await PostBesluit(a.Id, new { besluit = "Goedkeuren" });
      res.EnsureSuccessStatusCode();
      var body = (await res.Content.ReadFromJsonAsync<RecordBesluitResponse>())!;
      Assert.Equal("Goedgekeurd", body.Status.Tag);

      var detail = await _client.SendAsync(AsBehandelaar(HttpMethod.Get, $"/api/v1/beoordeling/{a.Id}"));
      var view = (await detail.Content.ReadFromJsonAsync<BeoordelingViewDto>())!;
      Assert.Equal("Goedgekeurd", view.Aanvraag.Status.Tag);
      Assert.False(view.Decisions.CanBesluiten); // terminal — no further decision allowed
    }
    finally
    {
      await DeleteAsAdmin(a.Id);
    }
  }

  [Fact]
  public async Task Afwijzen_requires_a_toelichting()
  {
    var (a, _) = await CreateManualCaseWithDocument();
    try
    {
      var missing = await PostBesluit(a.Id, new { besluit = "Afwijzen" });
      Assert.Equal(HttpStatusCode.BadRequest, missing.StatusCode);

      var res = await PostBesluit(a.Id, new { besluit = "Afwijzen", toelichting = "Diploma niet erkend" });
      res.EnsureSuccessStatusCode();
      var body = (await res.Content.ReadFromJsonAsync<RecordBesluitResponse>())!;
      Assert.Equal("Afgewezen", body.Status.Tag);
      Assert.Equal("Diploma niet erkend", body.Status.Reden);
    }
    finally
    {
      await DeleteAsAdmin(a.Id);
    }
  }

  [Fact]
  public async Task MeerInfoOpvragen_is_still_decidable_afterwards()
  {
    var (a, _) = await CreateManualCaseWithDocument();
    try
    {
      var res = await PostBesluit(a.Id, new { besluit = "MeerInfoOpvragen", toelichting = "Stuur een geldig diploma" });
      res.EnsureSuccessStatusCode();
      var body = (await res.Content.ReadFromJsonAsync<RecordBesluitResponse>())!;
      Assert.Equal("MeerInfoGevraagd", body.Status.Tag);

      var detail = await _client.SendAsync(AsBehandelaar(HttpMethod.Get, $"/api/v1/beoordeling/{a.Id}"));
      var view = (await detail.Content.ReadFromJsonAsync<BeoordelingViewDto>())!;
      Assert.True(view.Decisions.CanBesluiten); // not terminal — a decision can still follow
    }
    finally
    {
      await DeleteAsAdmin(a.Id);
    }
  }

  [Fact]
  public async Task Already_decided_case_rejects_a_further_besluit()
  {
    var (a, _) = await CreateManualCaseWithDocument();
    try
    {
      (await PostBesluit(a.Id, new { besluit = "Goedkeuren" })).EnsureSuccessStatusCode();
      var again = await PostBesluit(a.Id, new { besluit = "Afwijzen", toelichting = "te laat" });
      Assert.Equal(HttpStatusCode.Conflict, again.StatusCode);
    }
    finally
    {
      await DeleteAsAdmin(a.Id);
    }
  }

  // WP-68 (F2): the transition-legality check now runs inside RecordBesluit's write lock, so
  // two besluiten racing on the same still-open aanvraag can't both pass the check before
  // either writes — exactly one commits, the other sees the now-terminal status.
  [Fact]
  public async Task Concurrent_besluiten_on_the_same_aanvraag_yield_exactly_one_success()
  {
    var (a, _) = await CreateManualCaseWithDocument();
    try
    {
      var results = await Task.WhenAll(
          PostBesluit(a.Id, new { besluit = "Goedkeuren" }),
          PostBesluit(a.Id, new { besluit = "Afwijzen", toelichting = "race" }));

      var winner = Assert.Single(results, r => r.StatusCode == HttpStatusCode.OK);
      Assert.Single(results, r => r.StatusCode == HttpStatusCode.Conflict);

      // The persisted outcome must match whichever request actually won the race, not just
      // "some" besluit — the loser's write must never have landed.
      var winningTag = (await winner.Content.ReadFromJsonAsync<RecordBesluitResponse>())!.Status.Tag;
      var detail = await _client.SendAsync(AsBehandelaar(HttpMethod.Get, $"/api/v1/beoordeling/{a.Id}"));
      var finalTag = (await detail.Content.ReadFromJsonAsync<BeoordelingViewDto>())!.Aanvraag.Status.Tag;
      Assert.Equal(winningTag, finalTag);
    }
    finally
    {
      await DeleteAsAdmin(a.Id);
    }
  }

  [Fact]
  public async Task Unknown_id_404s_and_zorgverlener_is_forbidden()
  {
    var notFound = await PostBesluit("does-not-exist", new { besluit = "Goedkeuren" });
    Assert.Equal(HttpStatusCode.NotFound, notFound.StatusCode);

    var (a, _) = await CreateManualCaseWithDocument();
    try
    {
      var req = new HttpRequestMessage(HttpMethod.Post, $"/api/v1/beoordeling/{a.Id}/besluit")
      {
        Content = JsonContent.Create(new { besluit = "Goedkeuren" }),
      };
      req.Headers.Add("X-Role", "admin"); // zorgverlener, no X-Medewerker
      Assert.Equal(HttpStatusCode.Forbidden, (await _client.SendAsync(req)).StatusCode);
    }
    finally
    {
      await DeleteAsAdmin(a.Id);
    }
  }
}