// @vitest-environment jsdom
//
// Contract of the fixed-width count pill. Uses the REAL i18n instance (not a key-passthrough) so the
// plural selection (itemCount_one/_other) and the "1M+" overflow interpolation are actually exercised —
// those are the two branches worth guarding. English is forced so the singular/plural strings are stable.
import { describe, it, expect, beforeAll, afterEach } from "vitest";
import { render, screen, cleanup } from "@testing-library/react";
import "../i18n"; // side-effect: initialise the shared i18next instance
import i18n from "i18next";
import ItemCount from "./ItemCount";

beforeAll(async () => {
  await i18n.changeLanguage("en");
});
afterEach(cleanup);

const text = () => screen.getByTestId("item-count").textContent;

describe("ItemCount", () => {
  it("uses the singular string at 1 and the plural above it", () => {
    render(<ItemCount count={1} />);
    expect(text()).toBe("1 item");
  });

  it("pluralises and thousands-separates a normal count", () => {
    render(<ItemCount count={192045} />);
    // Separators come from toLocaleString (runtime-locale dependent) — compare against it, not a fixed
    // en-US string, so the test asserts ItemCount's formatting path rather than the CI locale.
    expect(text()).toBe(`${(192045).toLocaleString()} items`);
  });

  it("collapses a count of a million or more to 1M+, with the exact figure in the tooltip", () => {
    render(<ItemCount count={1_000_000} />);
    expect(text()).toBe("1M+ items"); // the "1M+" collapse is locale-independent
    expect(screen.getByTestId("item-count").getAttribute("title")).toBe(
      (1_000_000).toLocaleString(),
    );
  });

  it("shows the icon-only fixed box (empty label) while the count is undefined", () => {
    render(<ItemCount />);
    expect(text()).toBe(""); // the Layers icon carries no text
    expect(screen.getByTestId("item-count").getAttribute("title")).toBeNull();
  });
});