import { afterAll, afterEach, beforeAll, expect, test } from "bun:test";
import { readFileSync } from "node:fs";
import { GlobalRegistrator } from "@happy-dom/global-registrator";
import type { HomerBook } from "../src/content/homer";
import { createStore, DEFAULT_STATE, type AppState } from "../src/app/state";

beforeAll(() => GlobalRegistrator.register({ url: "http://localhost:3000/" }));
afterAll(() => GlobalRegistrator.unregister());

// Placeholder text only: never real lyrics in tests.
const library = {
  sagas: [{
    name: "The Cyclops Saga", year: 2023, cover: "/content/files/cyclops/folder.jpg",
    songs: [{ track: 1, title: "Polyphemus", audio: "/content/files/cyclops/01.flac", lyrics: { url: "/content/files/cyclops/01.lrc", timed: true } }],
  }],
};
const book: HomerBook = {
  book: 9, heading: "BOOK IX.", summary: "Summary line.",
  paragraphs: ["First paragraph.", "Second paragraph.", "Here the Cyclops appears.", "The end."],
};

let realFetch: typeof fetch;
function serve(mounted: boolean) {
  globalThis.fetch = (async (input: RequestInfo | URL) => {
    const url = String(input);
    if (mounted && url.endsWith("/content/library.json")) return Response.json(library);
    if (mounted && url.endsWith("/content/files/cyclops/01.lrc")) return new Response("[00:01.00]Line A\n[00:05.00]Line B\n[00:09.00]Line C\n");
    if (mounted && url.endsWith("/content/homer/odyssey/9.json")) return Response.json(book);
    return new Response("Not found", { status: 404 });
  }) as typeof fetch;
}

const flush = async () => { for (let i = 0; i < 6; i++) await new Promise((r) => setTimeout(r, 0)); };

let destroy: (() => void) | null = null;
afterEach(() => { destroy?.(); destroy = null; globalThis.fetch = realFetch; });
beforeAll(() => { realFetch = globalThis.fetch; });

async function mount(mounted: boolean, state: Partial<AppState> = {}) {
  serve(mounted);
  const content = await import("../src/app/content");
  await content.loadLibrary();
  const { mountPanel } = await import("../src/app/panel/panel");
  document.body.innerHTML = `<main class="shell" data-panel="open"><aside id="panel" class="panel"></aside></main>`;
  const root = document.getElementById("panel")!;
  const store = createStore({ ...DEFAULT_STATE, songId: "polyphemus", ...state }, { history: false });
  const panel = mountPanel(root, store, { timelineHidden: () => false });
  destroy = panel.destroy;
  await flush();
  return { root, store, panel };
}

test("About has no Watch and no listen button", async () => {
  const { root } = await mount(true, { tab: "about" });
  expect(root.querySelector(".about")).not.toBeNull();
  expect(root.querySelector(".watch")).toBeNull();
  expect(root.querySelector(".golisten")).toBeNull();
  expect(root.querySelector(".panel__title")!.textContent).toBe("Polyphemus");
});

test("Listen & lyrics has the player, the synced lyrics and Watch", async () => {
  const { root } = await mount(true, { tab: "listen" });
  expect(root.querySelector(".player")).not.toBeNull();
  expect(root.querySelector(".lyrics")).not.toBeNull();
  expect(root.querySelector(".watch .video-card")).not.toBeNull();
  expect(root.querySelectorAll(".lyrics button.ly")).toHaveLength(3);
  expect(root.querySelector("audio")).not.toBeNull();
});

test("clicking a lyric line seeks the audio there", async () => {
  const { root } = await mount(true, { tab: "listen" });
  const audio = root.querySelector("audio")!;
  (root.querySelectorAll<HTMLButtonElement>(".lyrics button.ly")[1]!).click();
  expect(audio.currentTime).toBe(5);
});

test("Paths shows the motif strip only while the timeline is closed", async () => {
  const { root, store } = await mount(true, { tab: "paths" });
  expect(root.querySelector(".paths")).not.toBeNull();
  expect(root.querySelector(".motif-strip")).toBeNull();
  store.set({ timeline: "closed" });
  expect(root.querySelector(".motif-strip")).not.toBeNull();
  store.set({ timeline: "open" });
  expect(root.querySelector(".motif-strip")).toBeNull();
});

test("Paths has a row per motif and the chart of all nine places", async () => {
  const { root } = await mount(true, { tab: "paths" });
  expect(root.querySelectorAll(".mrow").length).toBeGreaterThan(0);
  const places = [...root.querySelectorAll(".c-place")].map((t) => t.textContent);
  expect(places).toHaveLength(9);
  expect(places[0]).toBe("Troy");
  expect(places[8]).toBe("Ithaca");
});

test("Fan works shows the empty state", async () => {
  const { root } = await mount(true, { tab: "fan" });
  expect(root.querySelector(".fan")!.textContent).toContain(
    "No fan works collected yet. Real ones will be credited and linked to their creators.",
  );
});

test("without the content folder, Listen says so and has no audio", async () => {
  const { root } = await mount(false, { tab: "listen" });
  expect(root.querySelector(".listen")!.textContent).toContain("Content folder not mounted");
  expect(root.querySelector("audio")).toBeNull();
  expect(root.querySelector(".watch")).not.toBeNull();
});

test("the header play button switches to Listen & lyrics", async () => {
  const { root, store } = await mount(true, { tab: "about" });
  root.querySelector<HTMLButtonElement>(".pplay")!.click();
  expect(store.get().tab).toBe("listen");
  expect(root.querySelector(".listen")).not.toBeNull();
});

test("the reading view opens at the passage with the paragraphs before folded, and Back closes it", async () => {
  const { root, store } = await mount(true, { tab: "about", read: true });
  const reading = root.querySelector(".reading")!;
  expect(reading.textContent).toContain("Show the 2 paragraphs before");
  expect(reading.textContent).not.toContain("Roman");
  expect(reading.querySelectorAll(".reading__p")).toHaveLength(2);
  root.querySelector<HTMLButtonElement>(".reading__back")!.click();
  expect(store.get().read).toBe(false);
  expect(root.querySelector(".reading")).toBeNull();
});

test("changing the song re-renders the header", async () => {
  const { root, store } = await mount(true);
  store.set({ songId: "would-you-fall-in-love-with-me-again" });
  expect(root.querySelector(".panel__title")!.textContent).toBe("Would You Fall in Love with Me Again");
});

test("a long title can wrap: no nowrap on .panel__title", () => {
  const css = readFileSync(new URL("../src/app/panel/panel.css", import.meta.url), "utf8");
  const rule = /\.panel__title\s*\{[^}]*\}/.exec(css);
  expect(rule).not.toBeNull();
  expect(rule![0]).not.toContain("nowrap");
});