import { describe, test, expect } from "vitest";
import { readFileSync } from "node:fs";
import path from "node:path";
import { parseThemeChoice, nextThemeChoice } from "./theme";

describe("parseThemeChoice", () => {
  test("uebernimmt nur light und dark", () => {
    expect(parseThemeChoice("light")).toBe("light");
    expect(parseThemeChoice("dark")).toBe("dark");
  });

  test("faellt bei fehlendem oder fremdem Wert auf system zurueck", () => {
    expect(parseThemeChoice(undefined)).toBe("system");
    expect(parseThemeChoice("")).toBe("system");
    expect(parseThemeChoice("dark; path=/")).toBe("system");
    expect(parseThemeChoice("<script>")).toBe("system");
  });
});

describe("nextThemeChoice", () => {
  test("wechselt reihum Automatisch -> Hell -> Dunkel -> Automatisch", () => {
    expect(nextThemeChoice("system")).toBe("light");
    expect(nextThemeChoice("light")).toBe("dark");
    expect(nextThemeChoice("dark")).toBe("system");
  });
});

describe("Dunkelmodus-Tokens in globals.css", () => {
  test("gewaehlter und automatischer Dunkelblock sind identisch", () => {
    const css = readFileSync(path.join(process.cwd(), "src/app/globals.css"), "utf8");
    const explicit = css.match(/:root\[data-theme="dark"\] \{([\s\S]*?)\n\}/)?.[1];
    const system = css.match(/:root:not\(\[data-theme="light"\]\) \{([\s\S]*?)\n  \}/)?.[1];
    expect(explicit).toBeTruthy();
    expect(system).toBeTruthy();
    const normalize = (block: string) =>
      block
        .split("\n")
        .map((line) => line.trim())
        .filter(Boolean)
        .join("\n");
    expect(normalize(system!)).toBe(normalize(explicit!));
  });
});