import { describe, expect, it } from "vitest";

import {
  DEFAULT_WIND_SPEED_UNIT,
  formatTemperature,
  formatWindSpeed,
  isTemperatureUnit,
  isWindSpeedUnit,
} from "@/lib/weather-utils";

describe("weather utilities", () => {
  it("formats wind speed in km/h by default", () => {
    expect(DEFAULT_WIND_SPEED_UNIT).toBe("kmh");
    expect(formatWindSpeed(5, "en")).toBe("18 km/h");
  });

  it("formats selected temperature and wind units", () => {
    expect(formatTemperature(10, "en", "f")).toBe("50°F");
    expect(formatWindSpeed(4, "en", "mph")).toBe("9 mph");
    expect(formatWindSpeed(4, "en", "ms")).toBe("4.0 m/s");
  });

  it("validates supported presentation units", () => {
    expect(isTemperatureUnit("c")).toBe(true);
    expect(isTemperatureUnit("kelvin")).toBe(false);
    expect(isWindSpeedUnit("kmh")).toBe(true);
    expect(isWindSpeedUnit("knots")).toBe(false);
  });
});