import { describe, expect, it } from "vitest";
import { ytCountFrom, ytSearchFrom, ytSearchParams } from "./ytSearchUrlState";

const p = (q: string) => new URLSearchParams(q);

describe("the live YouTube search's address", () => {
  it("reads the term, trimmed; a blank one names no search", () => {
    expect(ytSearchFrom(p("yt=%20lofi%20"))).toBe("lofi");
    expect(ytSearchFrom(p("yt=%20%20"))).toBeNull();
    expect(ytSearchFrom(p("q=lofi"))).toBeNull();
  });

  it("reads one of the offered counts, else the default", () => {
    expect(ytCountFrom(p("ytn=60"))).toBe(60);
    expect(ytCountFrom(p("ytn=61"))).toBe(20);
    expect(ytCountFrom(p("ytn=x"))).toBe(20);
    expect(ytCountFrom(p(""))).toBe(20);
  });

  it("writes the count only off its default, and nothing with no search", () => {
    expect(ytSearchParams("lofi", 40)).toEqual({ yt: "lofi", ytn: "40" });
    expect(ytSearchParams("lofi", 20)).toEqual({ yt: "lofi", ytn: null });
    expect(ytSearchParams(null, 40)).toEqual({ yt: null, ytn: null });
  });

  it("round-trips", () => {
    const q = new URLSearchParams();
    for (const [k, v] of Object.entries(ytSearchParams("lofi beats", 100))) if (v) q.set(k, v);
    expect([ytSearchFrom(q), ytCountFrom(q)]).toEqual(["lofi beats", 100]);
  });
});