// #109 - Unit tests for /students endpoints
// Tests purs : fixtures, mock API, mock DB — aucun appel réseau réel

import { assertEquals, assertExists } from "@std/assert";
import { getFetchCalls, mockFetch, restoreFetch } from "../helpers/api_mock.ts";
import { createMockDb } from "../helpers/db_mock.ts";
import { type Student, students } from "../helpers/fixtures.ts";

// --- Fixtures ---

Deno.test("students: fixtures have correct shape", () => {
  assertEquals(students.length, 3);
  assertEquals(typeof students[0].numEtud, "number");
  assertEquals(typeof students[0].nom, "string");
  assertEquals(typeof students[0].prenom, "string");
  assertEquals(typeof students[0].idPromo, "string");
});

Deno.test("students: two students belong to the same promo", () => {
  const promo4 = students.filter((s) => s.idPromo === "4AFISE25/26");
  assertEquals(promo4.length, 2);
});

// --- Mock API - GET /students ---

Deno.test("mock API: GET /students returns list", async () => {
  mockFetch({ "/students": students });
  try {
    const res = await fetch("http://localhost/api/students");
    assertEquals(res.status, 200);
    const data: Student[] = await res.json();
    assertEquals(data.length, 3);
    assertExists(data.find((s) => s.nom === "Dupont"));
  } finally {
    restoreFetch();
  }
});

Deno.test("mock API: GET /students?idPromo filters by promo", async () => {
  const filtered = students.filter((s) => s.idPromo === "4AFISE25/26");
  mockFetch({ "/students": filtered });
  try {
    const res = await fetch(
      "http://localhost/api/students?idPromo=4AFISE25/26",
    );
    const data: Student[] = await res.json();
    assertEquals(data.length, 2);
    assertEquals(data.every((s) => s.idPromo === "4AFISE25/26"), true);
  } finally {
    restoreFetch();
  }
});

Deno.test("mock API: GET /students/:numEtud returns one student", async () => {
  mockFetch({ "/students/21212006": students[0] });
  try {
    const res = await fetch("http://localhost/api/students/21212006");
    assertEquals(res.status, 200);
    const data: Student = await res.json();
    assertEquals(data.numEtud, 21212006);
    assertEquals(data.nom, "Dupont");
  } finally {
    restoreFetch();
  }
});

Deno.test("mock API: GET /students/:numEtud 404 when not found", async () => {
  mockFetch({
    "/students/99999": {
      status: 404,
      body: { error: "Ressource introuvable" },
    },
  });
  try {
    const res = await fetch("http://localhost/api/students/99999");
    assertEquals(res.status, 404);
  } finally {
    restoreFetch();
  }
});

Deno.test("mock API: POST /students creates student", async () => {
  const newStudent = students[0];
  mockFetch({ "/students": { method: "POST", status: 201, body: newStudent } });
  try {
    const res = await fetch("http://localhost/api/students", {
      method: "POST",
      headers: { "content-type": "application/json" },
      body: JSON.stringify({
        nom: "Dupont",
        prenom: "Jean",
        idPromo: "4AFISE25/26",
      }),
    });
    assertEquals(res.status, 201);
    const data: Student = await res.json();
    assertEquals(data.nom, "Dupont");
  } finally {
    restoreFetch();
  }
});

Deno.test("mock API: PUT /students/:numEtud updates student", async () => {
  const updated = { ...students[0], nom: "Dupont-Modifié" };
  mockFetch({
    "/students/21212006": { method: "PUT", status: 200, body: updated },
  });
  try {
    const res = await fetch("http://localhost/api/students/21212006", {
      method: "PUT",
      headers: { "content-type": "application/json" },
      body: JSON.stringify({
        nom: "Dupont-Modifié",
        prenom: "Jean",
        idPromo: "4AFISE25/26",
      }),
    });
    assertEquals(res.status, 200);
    const data: Student = await res.json();
    assertEquals(data.nom, "Dupont-Modifié");
  } finally {
    restoreFetch();
  }
});

Deno.test("mock API: DELETE /students/:numEtud returns 204", async () => {
  mockFetch({ "/students/21212006": { method: "DELETE", status: 204 } });
  try {
    const res = await fetch("http://localhost/api/students/21212006", {
      method: "DELETE",
    });
    assertEquals(res.status, 204);
  } finally {
    restoreFetch();
  }
});

Deno.test("mock API: POST /students 400 on missing fields", async () => {
  mockFetch({ "/students": { method: "POST", status: 400 } });
  try {
    const res = await fetch("http://localhost/api/students", {
      method: "POST",
      headers: { "content-type": "application/json" },
      body: JSON.stringify({ nom: "Test" }),
    });
    assertEquals(res.status, 400);
  } finally {
    restoreFetch();
  }
});

// --- Mock DB ---

Deno.test("mock DB: find student by numEtud", () => {
  const db = createMockDb({ tables: { students: [...students] } });
  const s = db.findOne<Student>("students", (r) => r.numEtud === 21212006);
  assertExists(s);
  assertEquals(s.nom, "Dupont");
});

Deno.test("mock DB: filter students by idPromo", () => {
  const db = createMockDb({ tables: { students: [...students] } });
  const rows = db.findMany<Student>(
    "students",
    (s) => s.idPromo === "4AFISE25/26",
  );
  assertEquals(rows.length, 2);
});

Deno.test("mock DB: insert student increments count", () => {
  const db = createMockDb({ tables: { students: [...students] } });
  db.insert<Student>("students", {
    numEtud: 21212099,
    nom: "Test",
    prenom: "Ing",
    idPromo: "4AFISE25/26",
  });
  assertEquals(db.getTable("students").length, 4);
});

Deno.test("mock DB: update student nom", () => {
  const db = createMockDb({ tables: { students: [...students] } });
  const count = db.updateWhere<Student>(
    "students",
    (s) => s.numEtud === 21212006,
    { nom: "Nouveau" },
  );
  assertEquals(count, 1);
  assertEquals(
    db.findOne<Student>("students", (s) => s.numEtud === 21212006)?.nom,
    "Nouveau",
  );
});

Deno.test("mock DB: delete student removes exactly one", () => {
  const db = createMockDb({ tables: { students: [...students] } });
  const count = db.deleteWhere<Student>(
    "students",
    (s) => s.numEtud === 21212006,
  );
  assertEquals(count, 1);
  assertEquals(db.getTable("students").length, 2);
});

Deno.test("mock API: getFetchCalls tracks student requests", async () => {
  mockFetch({ "/students": students });
  try {
    await fetch("http://localhost/api/students");
    await fetch("http://localhost/api/students?idPromo=4AFISE25/26");
    const calls = getFetchCalls();
    assertEquals(calls.length, 2);
    assertEquals(calls[0].method, "GET");
  } finally {
    restoreFetch();
  }
});