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115export function createApi({
  sessions,
  projects,
  events,
  signingKey,
  seededBug = false,
}) {
  return createServer((request, response) => {
    const send = (status, body) => {
      response.writeHead(status, { "content-type": "application/json" });
      response.end(JSON.stringify(body));
    };
    const fail = (code) => {
      const [status, message] = errors[code];
      send(status, { error: { code, message } });
    };
    // Authenticate, then authorize. Malformed parameters must not change these results.
    const authorization = request.headers.authorization ?? "";
    const bearer = /^Bearer ([A-Za-z0-9_-]+)$/.exec(authorization);
    const tenantId = bearer ? sessions.get(bearer[1]) : undefined;
    if (!tenantId) return fail("unauthenticated");

    const url = new URL(request.url ?? "/", "http://127.0.0.1");
    const route = /^\/v1\/projects\/([^/]+)(\/events)?$/.exec(url.pathname);
    let projectId;
    try {
      projectId = route ? decodeURIComponent(route[1]) : undefined;
    } catch {
      return fail("not_found");
    }
    const project = projectId ? projects.get(projectId) : undefined;
    if (
      request.method !== "GET" ||
      !project ||
      project.tenant_id !== tenantId
    ) {
      return fail("not_found");
    }
    // Existing project-detail behavior remains independent of pagination parameters.
    if (!route[2]) return send(200, { id: projectId, name: project.name });

    const rawLimit = url.searchParams.get("limit");
    const limit = rawLimit === null ? 25 : Number(rawLimit);
    if (
      url.searchParams.getAll("limit").length > 1 ||
      (rawLimit !== null && !/^\d+$/.test(rawLimit)) ||
      !Number.isInteger(limit) ||
      limit < 1 ||
      limit > 100
    ) {
      return fail("invalid_limit");
    }
    let cursor;
    if (url.searchParams.has("cursor")) {
      try {
        if (url.searchParams.getAll("cursor").length !== 1)
          throw new Error("Invalid cursor");
        cursor = decodeCursor(
          url.searchParams.get("cursor"),
          tenantId,
          projectId,
          signingKey
        );
      } catch {
        return fail("invalid_cursor");
      }
    }

    const matching = events
      .filter(
        (event) =>
          event.tenant_id === tenantId && event.project_id === projectId
      )
      .sort(compareEvents)
      .filter((event) => {
        if (!cursor) return true;
        // Deliberate baseline defect: timestamp-only continuation loses tied rows.
        if (seededBug)
          return (
            timestampValue(event.created_at) < timestampValue(cursor.created_at)
          );
        return compareEvents(event, cursor) > 0;
      });
    const selected = matching.slice(0, limit);
    const items = selected.map(({ id, created_at, type, summary }) => ({
      id,
      created_at,
      type,
      summary,
    }));
    const nextCursor =
      matching.length > limit
        ? encodeCursor(selected.at(-1), tenantId, projectId, signingKey)
        : null;
    return send(200, { items, next_cursor: nextCursor });
  });
}

export async function startApi(fixtures, options = {}) {
  const server = createApi({ ...fixtures, ...options });
  await new Promise((resolve, reject) => {
    server.once("error", reject);
    server.listen(0, "127.0.0.1", () => resolve(undefined));
  });
  const address = server.address();
  if (!address || typeof address === "string")
    throw new Error("No listening address");
  return {
    baseUrl: `http://127.0.0.1:${address.port}`,
    close: () =>
      new Promise((resolve, reject) =>
        server.close((error) => (error ? reject(error) : resolve(undefined)))
      ),
  };
}

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62export function createFixtures() {
  const tokenA = randomBytes(24).toString("base64url");
  const tokenB = randomBytes(24).toString("base64url");
  const sessions = new Map([
    [tokenA, "tenant_a"],
    [tokenB, "tenant_b"],
  ]);
  const projects = new Map([
    ["feed", { tenant_id: "tenant_a", name: "Activity feed" }],
    ["empty", { tenant_id: "tenant_a", name: "Empty feed" }],
    ["exact", { tenant_id: "tenant_a", name: "Four events" }],
    ["large", { tenant_id: "tenant_a", name: "Large feed" }],
    ["precision", { tenant_id: "tenant_a", name: "Precise timestamps" }],
    ["other", { tenant_id: "tenant_a", name: "Another project" }],
    ["private", { tenant_id: "tenant_b", name: "Private project" }],
  ]);
  const event = (id, created_at, project_id, tenant_id = "tenant_a") => ({
    id,
    created_at,
    project_id,
    tenant_id,
    type: "deployment",
    summary: `Synthetic event ${id}`,
    internal_note: "This field must never enter the HTTP response.",
    raw_payload: { synthetic: true },
  });
  const feed = [
    event("evt_105", "2026-01-15T12:00:03.123456Z", "feed"),
    event("evt_104", "2026-01-15T12:00:02.123456Z", "feed"),
    event("evt_103", "2026-01-15T12:00:02.123456Z", "feed"),
    event("evt_102", "2026-01-15T12:00:02.123456Z", "feed"),
    event("evt_101", "2026-01-15T12:00:01.123456Z", "feed"),
  ];
  const events = [
    ...feed,
    ...feed.slice(0, 4).map((item) => ({ ...item, project_id: "exact" })),
    ...Array.from({ length: 105 }, (_, index) =>
      event(
        `large_${String(index).padStart(3, "0")}`,
        new Date(Date.UTC(2026, 0, 15, 12, 0, index))
          .toISOString()
          .replace(".000Z", ".123456Z"),
        "large"
      )
    ),
    // Reverse ID order makes timestamp precision observable in the tests.
    event("precise_a", "2026-01-15T12:00:00.123999Z", "precision"),
    event("precise_z", "2026-01-15T12:00:00.123001Z", "precision"),
    event("other_1", "2026-01-15T12:00:00.123456Z", "other"),
    event("other_2", "2026-01-15T11:59:59.123456Z", "other"),
    event("private_1", "2026-01-15T12:00:00.123456Z", "private", "tenant_b"),
    event("private_2", "2026-01-15T11:59:59.123456Z", "private", "tenant_b"),
  ];
  return {
    sessions,
    projects,
    events,
    signingKey: randomBytes(32),
    tokenA,
    tokenB,
  };
}

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350test("five-event traversal crosses a timestamp tie and replays the same continuation", async () => {
  const expected = ["evt_105", "evt_104", "evt_103", "evt_102", "evt_101"];
  const pages = await traverse("feed", 2, expected);
  assert.deepEqual(pages.map(ids), [
    ["evt_105", "evt_104"],
    ["evt_103", "evt_102"],
    ["evt_101"],
  ]);
  assert.equal(pages.length, 3);
  assert.ok(pages[0].next_cursor);
  assert.ok(pages[1].next_cursor);
  assert.equal(pages[2].next_cursor, null);
  const replay = await request("feed", {
    limit: "2",
    cursor: pages[0].next_cursor,
  });
  assert.deepEqual(replay.body.items, pages[1].items);
  const next = await request("feed", {
    limit: "2",
    cursor: replay.body.next_cursor,
  });
  assert.deepEqual(next.body.items, pages[2].items);
  assert.equal(next.body.next_cursor, null);
  console.log(
    JSON.stringify({
      fixture: "five-event-tie",
      pages: pages.map(ids),
      requests: pages.length,
      replay: ids(replay.body),
    })
  );
});

test("the same tie group traverses correctly with limit three", async () => {
  const pages = await traverse("feed", 3, [
    "evt_105",
    "evt_104",
    "evt_103",
    "evt_102",
    "evt_101",
  ]);
  assert.deepEqual(pages.map(ids), [
    ["evt_105", "evt_104", "evt_103"],
    ["evt_102", "evt_101"],
  ]);
});

test("timestamp ordering and continuation preserve submillisecond precision", async () => {
  const pages = await traverse("precision", 1, ["precise_a", "precise_z"]);
  assert.equal(pages[0].items[0].created_at, "2026-01-15T12:00:00.123999Z");
  assert.equal(pages[1].items[0].created_at, "2026-01-15T12:00:00.123001Z");
});

test("omitted, minimum, and maximum limits return 25, 1, and 100 of 105 events", async () => {
  for (const [parameters, expected] of [
    [{}, 25],
    [{ limit: "1" }, 1],
    [{ limit: "100" }, 100],
  ]) {
    const result = await request("large", parameters);
    assert.equal(result.status, 200);
    assert.equal(result.body.items.length, expected);
    assert.ok(result.body.next_cursor);
  }
  const pages = await traverse(
    "large",
    100,
    Array.from(
      { length: 105 },
      (_, index) => `large_${String(104 - index).padStart(3, "0")}`
    )
  );
  assert.deepEqual(
    pages.map((page) => page.items.length),
    [100, 5]
  );
});

test("invalid and repeated limits return the documented generic error", async (context) => {
  for (const limit of [
    "0",
    "101",
    "-1",
    "1.5",
    "many",
    "",
    "1e2",
    "Infinity",
  ]) {
    await context.test(`limit ${JSON.stringify(limit)}`, async () => {
      const result = await request("feed", { limit });
      assert.equal(result.status, 400);
      assert.deepEqual(
        result.body,
        expectedError(
          "invalid_limit",
          "Limit must be an integer from 1 through 100."
        )
      );
    });
  }
  const repeated = await request("feed", [
    ["limit", "1"],
    ["limit", "2"],
  ]);
  assert.equal(repeated.status, 400);
});

test("empty, partial, and exactly full final pages have no continuation", async () => {
  assert.deepEqual((await request("empty")).body, {
    items: [],
    next_cursor: null,
  });
  const partial = await traverse("feed", 2, [
    "evt_105",
    "evt_104",
    "evt_103",
    "evt_102",
    "evt_101",
  ]);
  assert.equal(partial.at(-1).items.length, 1);
  const exact = await traverse("exact", 2, [
    "evt_105",
    "evt_104",
    "evt_103",
    "evt_102",
  ]);
  assert.deepEqual(
    exact.map((page) => page.items.length),
    [2, 2]
  );
  assert.equal(exact[1].next_cursor, null);
});

test("authentication precedes malformed and wrong-scope cursor or limit validation", async () => {
  const privateCursor = (
    await request("private", { limit: "1" }, fixtures.tokenB)
  ).body.next_cursor;
  for (const token of [null, "invalid_session"]) {
    for (const parameters of [
      { cursor: "broken" },
      { cursor: privateCursor },
      { limit: "0", cursor: "broken" },
    ]) {
      const result = await request("feed", parameters, token);
      assert.equal(result.status, 401);
      assert.deepEqual(result.body, unauthenticated);
    }
  }
});

test("inaccessible and nonexistent projects return identical 404 before cursor validation", async () => {
  const ownCursor = (await request("feed", { limit: "1" })).body.next_cursor;
  for (const project of ["private", "missing"]) {
    for (const parameters of [
      {},
      { cursor: "broken" },
      { cursor: ownCursor },
      { limit: "0", cursor: "broken" },
    ]) {
      const result = await request(project, parameters);
      assert.equal(result.status, 404);
      assert.deepEqual(result.body, notFound);
    }
  }
});

test("a valid cursor from another project in the same tenant is invalid on an authorized feed", async () => {
  const cursor = (await request("other", { limit: "1" })).body.next_cursor;
  assert.ok(cursor);
  const result = await request("feed", { cursor });
  assert.equal(result.status, 400);
  assert.deepEqual(result.body, invalidCursor);
});

test("a valid cursor from another tenant is invalid on an authorized feed", async () => {
  const cursor = (await request("private", { limit: "1" }, fixtures.tokenB))
    .body.next_cursor;
  assert.ok(cursor);
  const result = await request("feed", { cursor });
  assert.equal(result.status, 400);
  assert.deepEqual(result.body, invalidCursor);
});

test("undecodable, empty, tampered, and repeated cursor tokens return the same closed error", async () => {
  const cursor = (await request("feed", { limit: "1" })).body.next_cursor;
  const [payload, signature] = cursor.split(".");
  const tampered = `${payload}.${signature[0] === "A" ? "B" : "A"}${signature.slice(1)}`;
  for (const token of [
    "broken",
    "",
    "%%%.___",
    "a.b.c",
    "x".repeat(2049),
    tampered,
  ]) {
    const result = await request("feed", { cursor: token });
    assert.equal(result.status, 400);
    assert.deepEqual(result.body, invalidCursor);
  }
  const result = await request("feed", [
    ["cursor", cursor],
    ["cursor", cursor],
  ]);
  assert.equal(result.status, 400);
  assert.deepEqual(result.body, invalidCursor);
});

test("signed structurally invalid payloads and unsupported versions are rejected", async (context) => {
  const valid = {
    version: 1,
    tenant_id: "tenant_a",
    project_id: "feed",
    created_at: "2026-01-15T12:00:02.123456Z",
    id: "evt_104",
  };
  const missing = { ...valid };
  delete missing.id;
  const cases = [
    ["missing ID", missing],
    ["number ID", { ...valid, id: 104 }],
    ["empty ID", { ...valid, id: "" }],
    ["number timestamp", { ...valid, created_at: 0 }],
    ["invalid date", { ...valid, created_at: "2026-02-30T12:00:00Z" }],
    ["unsupported version", { ...valid, version: 2 }],
    ["extra field", { ...valid, extra: true }],
    ["wrong tenant type", { ...valid, tenant_id: 1 }],
    ["wrong project type", { ...valid, project_id: null }],
    ["null payload", null],
    ["array payload", []],
    ["invalid JSON", "not-json"],
  ];
  for (const [name, payload] of cases) {
    await context.test(name, async () => {
      const result = await request("feed", { cursor: signFixture(payload) });
      assert.equal(result.status, 400);
      assert.deepEqual(result.body, invalidCursor);
    });
  }
});

test("every serialized event omits stored tenant, project, and raw payload fields", async () => {
  const result = await request("feed", { limit: "100" });
  assert.equal(result.status, 200);
  for (const item of result.body.items) {
    assert.deepEqual(Object.keys(item).sort(), [
      "created_at",
      "id",
      "summary",
      "type",
    ]);
  }
  assert.ok(
    fixtures.events.some((event) => event.internal_note && event.raw_payload)
  );
});

test("the schema oracle rejects extra, missing, incorrectly typed, and malformed public fields", () => {
  const schema = specification.components.schemas.EventPage;
  const page = {
    items: [
      {
        id: "evt_1",
        created_at: "2026-01-15T12:00:00.123456Z",
        type: "deployment",
        summary: "Synthetic",
      },
    ],
    next_cursor: null,
  };
  assert.ok(conforms(page, schema));
  assert.equal(conforms({ ...page, tenant_id: "tenant_a" }, schema), false);
  assert.equal(
    conforms(
      { ...page, items: [{ ...page.items[0], raw_payload: {} }] },
      schema
    ),
    false
  );
  assert.equal(conforms({ items: page.items }, schema), false);
  assert.equal(conforms({ ...page, next_cursor: "" }, schema), false);
  assert.equal(
    conforms({ ...page, items: [{ ...page.items[0], id: 1 }] }, schema),
    false
  );
  assert.equal(
    conforms(
      { ...page, items: [{ ...page.items[0], created_at: "yesterday" }] },
      schema
    ),
    false
  );
  const errorSchema = specification.components.schemas.InvalidCursor;
  assert.equal(
    conforms(
      { error: { ...invalidCursor.error, stack: "internal" } },
      errorSchema
    ),
    false
  );
  assert.equal(
    conforms(
      { error: { ...invalidCursor.error, message: "tenant_a" } },
      errorSchema
    ),
    false
  );
});

test("the existing project-detail route preserves access and ignores pagination parameters", async () => {
  const own = await request(
    "feed",
    { cursor: "broken", limit: "0" },
    fixtures.tokenA,
    true
  );
  assert.equal(own.status, 200);
  assert.deepEqual(own.body, { id: "feed", name: "Activity feed" });
  const inaccessible = await request("private", {}, fixtures.tokenA, true);
  assert.equal(inaccessible.status, 404);
  assert.deepEqual(inaccessible.body, notFound);
  const unauthenticatedResult = await request("feed", {}, null, true);
  assert.equal(unauthenticatedResult.status, 401);
  assert.deepEqual(unauthenticatedResult.body, unauthenticated);
});

test("OpenAPI declares operation, limit boundaries, signed cursor, and response statuses", () => {
  assert.equal(specification.openapi, "3.1.0");
  const operation = specification.paths["/v1/projects/{project_id}/events"].get;
  assert.equal(operation.operationId, "listProjectEvents");
  const limit = operation.parameters.find(
    (parameter) => parameter.name === "limit"
  ).schema;
  assert.deepEqual(limit, {
    type: "integer",
    minimum: 1,
    maximum: 100,
    default: 25,
  });
  assert.deepEqual(Object.keys(operation.responses).sort(), [
    "200",
    "400",
    "401",
    "404",
  ]);
  assert.equal(
    specification.components.securitySchemes.session.scheme,
    "bearer"
  );
});

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76mkdirSync(output, { recursive: true });
const states = [];
for (const [name, arguments_] of [
  ["red", ["--seeded"]],
  ["green", []],
]) {
  const result = spawnSync(
    process.execPath,
    [resolve(directory, "test.mjs"), ...arguments_],
    {
      cwd: directory,
      encoding: "utf8",
      timeout: 30_000,
    }
  );
  writeFileSync(
    resolve(output, `${name}.log`),
    `${result.stdout ?? ""}${result.stderr ?? ""}`
  );
  states.push({
    name,
    command: `node test.mjs${arguments_.length ? " --seeded" : ""}`,
    exit_code: result.status,
    signal: result.signal,
    error: result.error?.message ?? null,
  });
}
const sources = Object.fromEntries(
  readdirSync(directory, { withFileTypes: true })
    .filter((entry) => entry.isFile())
    .map((entry) => [
      entry.name,
      createHash("sha256")
        .update(readFileSync(resolve(directory, entry.name)))
        .digest("hex"),
    ])
);
const observed = { red: await observe(true), green: await observe(false) };
writeJson("observed-http.json", observed);
writeJson("run-manifest.json", {
  execution: "Synthetic loopback HTTP fixture; no external service",
  recorded_at: new Date().toISOString(),
  node: process.version,
  minimum_node: "22.6.0",
  dependencies: "Node standard library only; no install step",
  baseline:
    "Deliberately seeded timestamp-only continuation; not a historical customer defect",
  correction:
    "Descending timestamp-and-ID tuple continuation using full fractional precision",
  source_sha256: sources,
  states,
});
if (
  states[0].exit_code === null ||
  states[0].exit_code === 0 ||
  states[1].exit_code !== 0
) {
  throw new Error(
    "Expected the unchanged tests to fail on the seeded baseline and pass on the corrected implementation. Inspect red.log and green.log."
  );
}
console.log(
  JSON.stringify(
    {
      execution: "synthetic-loopback-http",
      red_exit: states[0].exit_code,
      green_exit: states[1].exit_code,
      green_pages: observed.green.pages.map((page) =>
        page.body.items.map((item) => item.id)
      ),
      evidence_directory: output,
    },
    null,
    2
  )
);