import { describe, expect, it } from "vitest";
import { isLocale, matchLocale } from "@/lib/i18n/locales";

describe("isLocale", () => {
    it("accepts supported locales", () => {
        expect(isLocale("tr")).toBe(true);
        expect(isLocale("en")).toBe(true);
        expect(isLocale("de")).toBe(true);
    });

    it("rejects anything else", () => {
        expect(isLocale("fr")).toBe(false);
        expect(isLocale("")).toBe(false);
    });
});

describe("matchLocale", () => {
    it("defaults without a header", () => {
        expect(matchLocale(null)).toBe("tr");
        expect(matchLocale("")).toBe("tr");
    });

    it("matches primary ranges", () => {
        expect(matchLocale("en-US,en;q=0.9")).toBe("en");
        expect(matchLocale("de-DE,de;q=0.9,en;q=0.8")).toBe("de");
    });

    it("respects q-values", () => {
        expect(matchLocale("en;q=0.5,tr;q=0.9")).toBe("tr");
    });

    it("falls back on unknown or wildcard ranges", () => {
        expect(matchLocale("fr-FR,fr;q=0.9")).toBe("tr");
        expect(matchLocale("*")).toBe("tr");
    });
});