// Undercooked — the result screen (phase 07 task 02).
//
// The verdict, as the `round` frame carries it: the result word, the
// stars (1–3, the pop is decorative and `prefers-reduced-motion`-gated),
// score against target, the session's best for the level that was
// played, the per-player contribution list (display only — PLAN §5:
// never competitive gatekeeping), the counters (`served` / `missed` /
// `wasted`, the longest streak), and the three exits — *Next level*
// (only when `round.unlocked` names a level), *Retry* (`next_level`)
// and *Back to lobby* (`to_lobby`). The outcome is announced to screen
// readers through an `aria-live="polite"` region.

import { el, frag } from "./dom.js";

let bestEl = null;
let bannerEl = null;

function starsFor(stars) {
  const count = Math.max(0, Math.min(3, stars));
  const spans = [];
  for (let i = 0; i < 3; i += 1) {
    spans.push(
      el("span", { class: i < count ? "star filled" : "star", "aria-hidden": "true" },
        i < count ? "★" : "☆"),
    );
  }
  return el("p", {
    id: "stars",
    class: "stars",
    "aria-label": `${count} of 3 stars`,
  }, frag(...spans));
}

function resultWord(result) {
  if (result === "won") return "Won";
  if (result === "lost") return "Lost";
  if (result === "aborted") return "Aborted";
  return "Round over";
}

function announcement(result, score, target, stars) {
  const word = result === "won" ? "won" : result === "lost" ? "lost" : "ended";
  return `You ${word} ${score} of ${target} points with ${stars} star${stars === 1 ? "" : "s"}.`;
}

export function mount(target, _data, app) {
  const round = app.round ?? {};
  const result = round.result ?? null;
  const stars = round.stars ?? 0;
  const score = round.score ?? 0;
  const targetScore = round.target ?? 0;

  const players = (round.players ?? []).map((player) =>
    el("li", { class: "result-player" },
      el("span", { class: "seat-name" }, player.name),
      el("span", {}, `${player.score} pts · ${player.dishes_served} dish${player.dishes_served === 1 ? "" : "es"}`),
    ),
  );
  const counters = round.counters ?? {};
  bestEl = el("p", { id: "best-line" }, "Best: loading…");
  bannerEl = el("p", { class: "hint", id: "result-banner", hidden: true, role: "status", "aria-live": "polite" });

  const actions = el("div", { class: "result-actions" },
    el("button", {
      id: "retry-btn",
      class: "btn",
      type: "button",
      onClick: () => app.nextLevel(),
    }, "Retry"),
    el("button", {
      id: "to-lobby-btn",
      class: "btn btn-primary",
      type: "button",
      onClick: () => app.toLobby(),
    }, "Back to lobby"),
  );
  if (round.unlocked !== null && round.unlocked !== undefined) {
    actions.prepend(
      el("button", {
        id: "next-level-btn",
        class: "btn btn-primary",
        type: "button",
        onClick: () => app.nextLevel(),
      }, "Next level"),
    );
  }

  target.append(
    el("div", { class: "panel result" },
      el("h2", { id: "result-word" }, resultWord(result)),
      starsFor(stars),
      el("p", { id: "score-line" }, `Score ${score} of ${targetScore}`),
      bestEl,
      el("h3", { class: "section-label" }, "Cooks"),
      players.length === 0
        ? el("p", { class: "hint" }, "no players")
        : el("ul", { id: "result-players", class: "seat-list" }, frag(...players)),
      el("p", { id: "counters-line" },
        `Served ${counters.served ?? 0} · Missed ${counters.missed ?? 0} · Wasted ${counters.wasted ?? 0} · Longest streak ${round.longest_streak ?? 0}`),
      actions,
      bannerEl,
    ),
    el("p", {
      id: "result-announce",
      class: "visually-hidden",
      role: "status",
      "aria-live": "polite",
    }, announcement(result, score, targetScore, stars)),
  );
  // The best for the level that was played (the session update lands
  // with the `round` frame — `round_over` records before it broadcasts).
  void app.fetchSession().then(() => {
    if (bestEl !== null) renderBest(app);
  });
}

export function renderBest(app) {
  if (bestEl === null) return;
  const round = app.round ?? {};
  const session = app.session;
  const best = session !== null && round.level_id !== undefined ? session.best?.[round.level_id] : undefined;
  bestEl.textContent =
    best !== undefined
      ? `Best: ${best.score} pts, ${"★".repeat(best.stars)}${"☆".repeat(3 - best.stars)}`
      : "Best: —";
}

/** Same-screen re-show: re-render the best line (a `round` re-broadcast
 *  or a session refresh). */
export function update(_data, app) {
  if (app !== undefined) renderBest(app);
}

export function setBanner(message) {
  if (bannerEl === null) return;
  bannerEl.textContent = message ?? "";
  bannerEl.hidden = message === null || message === "";
}

export function unmount() {
  bestEl = null;
  bannerEl = null;
}