const MODEL_ID = "onnx-community/tiny-aya-global-ONNX";
const TRANSFORMERS_CDN = "https://cdn.jsdelivr.net/npm/@huggingface/transformers@4.0.1";
const MODEL_DTYPE = "q4f16";
const GENERATION_OPTIONS = {
  max_new_tokens: 360,
  do_sample: true,
  temperature: 0.3,
  top_p: 0.95,
};

const state = {
  game: null,
  clip: null,
  wordLimit: 12,
  history: [],
  currentJudged: false,
  transformers: null,
  modelPromise: null,
  judge: null,
  judgeAvailable: false,
};

const $ = (id) => document.getElementById(id);
const screens = {
  start: $("start-screen"),
  loading: $("loading-screen"),
  game: $("game-screen"),
  end: $("end-screen"),
};

function showScreen(name) {
  Object.entries(screens).forEach(([key, node]) => {
    node.classList.toggle("hidden", key !== name);
  });
}

async function api(path, payload = null) {
  const response = await fetch(path, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: payload === null ? "{}" : JSON.stringify(payload),
  });
  const data = await response.json();
  if (!response.ok || !data.ok) {
    throw new Error(data.error || "Race control could not complete that request.");
  }
  return data;
}

function setLoading(title, detail, progress = null) {
  $("loading-title").textContent = title;
  $("loading-detail").textContent = detail || "";
  if (progress !== null) {
    $("loading-progress").style.width = `${Math.max(0, Math.min(100, progress))}%`;
  }
}

function formatBytes(bytes) {
  if (!Number.isFinite(bytes) || bytes <= 0) return "";
  const units = ["B", "KB", "MB", "GB"];
  let value = bytes;
  let unitIndex = 0;
  while (value >= 1024 && unitIndex < units.length - 1) {
    value /= 1024;
    unitIndex += 1;
  }
  return `${value.toFixed(value >= 10 || unitIndex === 0 ? 0 : 1)} ${units[unitIndex]}`;
}

function countWords(text) {
  const matches = String(text || "").match(/[A-Za-z0-9]+(?:[-'][A-Za-z0-9]+)?/g);
  return matches ? matches.length : 0;
}

function clamp(value) {
  return Math.max(0, Math.min(100, Math.round(Number(value) || 0)));
}

function updateWordCount() {
  const words = countWords($("reply-input").value);
  $("word-count").textContent = `Words: ${words} / ${state.wordLimit}`;
  $("word-count").classList.toggle("over", words > state.wordLimit);
}

function renderRoundDots() {
  const dots = $("round-dots");
  dots.replaceChildren();
  for (let index = 1; index <= state.game.max_rounds; index += 1) {
    const dot = document.createElement("span");
    dot.className = index === state.game.round ? "active" : index < state.game.round ? "done" : "";
    dots.append(dot);
  }
}

function renderMeters() {
  for (const key of ["trust", "pace", "chaos", "tyre_risk"]) {
    const domKey = key.replace("_", "-");
    const value = clamp(state.game[key]);
    $(`${domKey}-value`).textContent = value;
    $(`${domKey}-meter`).style.width = `${value}%`;
  }
}

function formatDate(raw) {
  if (!raw || raw === "Unknown date") return raw || "--";
  const year = String(raw).slice(0, 10);
  return year;
}

function renderClip() {
  state.currentJudged = false;
  $("round-label").textContent = `Round ${state.game.round} / ${state.game.max_rounds}`;
  $("clip-audio").src = state.clip.audio_url;
  $("transcript").textContent = `\u201c${state.clip.transcription}\u201d`;
  $("driver-id").textContent = state.clip.driver_id || "--";
  $("grand-prix").textContent = state.clip.grand_prix || "--";
  $("session-date").textContent = formatDate(state.clip.session_date);
  $("reply-input").value = "";
  $("reply-input").disabled = false;
  $("submit-button").disabled = false;
  $("submit-button").classList.remove("hidden");
  $("next-button").classList.add("hidden");
  $("next-button").textContent = "Next Radio";
  updateWordCount();
  renderRoundDots();
  renderMeters();
}

function racingTermScore(reply) {
  const terms = [
    "box", "push", "manage", "tyre", "tyres", "fronts", "rears", "plan", "delta",
    "target", "lap", "undercut", "overcut", "brake", "lift", "coast", "mode",
    "safety", "car", "drs", "gap", "copy",
  ];
  const text = reply.toLowerCase();
  return terms.reduce((total, term) => total + (text.includes(term) ? 1 : 0), 0);
}

function fallbackJudge(reply) {
  const wordCount = countWords(reply);
  const over = wordCount > state.wordLimit;
  const empty = wordCount === 0;
  const vibe = Math.min(10, 3 + racingTermScore(reply) * 2);
  const clarity = empty ? 0 : Math.min(10, reply.length < 90 ? 7 : 5);
  const brevity = over ? 2 : Math.max(5, 10 - Math.max(0, wordCount - 7));
  const risk = over ? 7 : reply.toLowerCase().includes("push") ? 5 : 3;
  const fit = Math.min(10, Math.round((clarity + vibe) / 2));

  let delta = {
    trust: empty ? -8 : Math.round((clarity - 5) + (vibe > 6 ? 2 : 0)),
    pace: empty ? -4 : reply.toLowerCase().includes("push") ? 4 : Math.max(0, fit - 6),
    chaos: empty ? 8 : Math.round(5 - brevity),
    tyre_risk: reply.toLowerCase().includes("push") ? 3 : reply.toLowerCase().includes("manage") ? -2 : 1,
  };

  if (over) {
    delta = { trust: -4, pace: -1, chaos: 5, tyre_risk: 0 };
  }

  const verdict = empty
    ? "Silence is rarely a strategy."
    : over
      ? "Too many words. The radio channel gave up halfway through."
      : vibe >= 7
        ? "Clear enough for a stressed driver and nicely pit-wall coded."
        : "Understandable, but it needs more race-engineer bite.";

  const driverReaction = empty
    ? "Say again? I got nothing."
    : over
      ? "Mate, I cannot process all that."
      : vibe >= 7
        ? "Copy. That is a plan."
        : "Okay, but be more specific next time.";

  return {
    word_count: wordCount,
    is_over_limit: over,
    clarity,
    brevity,
    fit,
    f1_vibe: vibe,
    risk,
    delta,
    verdict,
    driver_reaction: driverReaction,
  };
}

function hasJudgeShape(value) {
  return Boolean(
    value
    && typeof value === "object"
    && value.delta
    && typeof value.delta === "object"
    && ("verdict" in value || "driver_reaction" in value)
  );
}

function findJsonObject(text) {
  const source = String(text || "");
  const starts = [];
  for (let i = 0; i < source.length; i += 1) {
    if (source[i] === "{") starts.push(i);
  }
  const candidates = [];
  for (const start of starts) {
    let depth = 0;
    for (let i = start; i < source.length; i += 1) {
      if (source[i] === "{") depth += 1;
      if (source[i] === "}") depth -= 1;
      if (depth === 0) {
        try {
          const raw = source.slice(start, i + 1);
          candidates.push({ value: JSON.parse(raw), length: raw.length });
        } catch {
          // Keep scanning; the model may wrap valid JSON after malformed text.
        }
        break;
      }
    }
  }
  const judgeCandidates = candidates.filter((candidate) => hasJudgeShape(candidate.value));
  return judgeCandidates.at(-1)?.value
    || candidates.sort((a, b) => b.length - a.length)[0]?.value
    || null;
}

function score10(value, fallback) {
  const number = Number(value);
  if (!Number.isFinite(number)) return fallback;
  return Math.max(0, Math.min(10, Math.round(number)));
}

function normalizeJudge(raw, reply) {
  const fallback = fallbackJudge(reply);
  if (!raw || typeof raw !== "object") return fallback;
  const delta = raw.delta && typeof raw.delta === "object" ? raw.delta : {};
  return {
    word_count: countWords(reply),
    is_over_limit: countWords(reply) > state.wordLimit,
    clarity: score10(raw.clarity, fallback.clarity),
    brevity: score10(raw.brevity, fallback.brevity),
    fit: score10(raw.fit, fallback.fit),
    f1_vibe: score10(raw.f1_vibe, fallback.f1_vibe),
    risk: score10(raw.risk, fallback.risk),
    delta: {
      trust: Math.max(-10, Math.min(10, Math.round(Number(delta.trust ?? fallback.delta.trust)))),
      pace: Math.max(-10, Math.min(10, Math.round(Number(delta.pace ?? fallback.delta.pace)))),
      chaos: Math.max(-10, Math.min(10, Math.round(Number(delta.chaos ?? fallback.delta.chaos)))),
      tyre_risk: Math.max(-10, Math.min(10, Math.round(Number(delta.tyre_risk ?? fallback.delta.tyre_risk)))),
    },
    verdict: String(raw.verdict || fallback.verdict).slice(0, 160),
    driver_reaction: String(raw.driver_reaction || fallback.driver_reaction).slice(0, 120),
  };
}

async function ensureJudgeModel() {
  if (state.judge) return state.judge;
  if (state.modelPromise) return state.modelPromise;
  if (!navigator.gpu) {
    throw new Error("WebGPU is not available in this browser.");
  }

  state.modelPromise = (async () => {
    const mod = await import(TRANSFORMERS_CDN);
    mod.env.allowLocalModels = false;
    state.transformers = mod;

    const progress_callback = (event) => {
      if (!event) return;
      const file = event.file ? ` ${event.file}` : "";
      const status = event.status || "Downloading";
      const rawProgress = Number(event.progress);
      const loaded = formatBytes(Number(event.loaded));
      const total = formatBytes(Number(event.total));
      const sizeDetail = loaded && total ? ` (${loaded} / ${total})` : "";
      const progress = Number.isFinite(rawProgress) ? rawProgress : null;
      setLoading("Downloading Tiny Aya", `${status}${file}${sizeDetail}`.trim(), progress);
    };

    const tokenizer = await mod.AutoTokenizer.from_pretrained(MODEL_ID, { progress_callback });
    const model = await mod.AutoModelForCausalLM.from_pretrained(MODEL_ID, {
      dtype: MODEL_DTYPE,
      device: "webgpu",
      progress_callback,
    });
    state.judge = { tokenizer, model };
    state.judgeAvailable = true;
    return state.judge;
  })().catch((error) => {
    state.modelPromise = null;
    state.judgeAvailable = false;
    throw error;
  });

  return state.modelPromise;
}

async function judgeWithModel(reply) {
  const { tokenizer, model } = await ensureJudgeModel();
  const { TextStreamer } = state.transformers;
  const schema = `{
  "word_count": 7,
  "is_over_limit": false,
  "clarity": 8,
  "brevity": 10,
  "fit": 7,
  "f1_vibe": 9,
  "risk": 3,
  "delta": {"trust": 6, "pace": 3, "chaos": -2, "tyre_risk": 1},
  "verdict": "Clear, decisive, and properly pit-wall coded." | "Incomprehensible - do you want your driver to crash??",
  "driver_reaction": "Copy. Finally, a plan." | "What? I'll end up dead last if I do that!"
}`;
  const messages = [
    {
      role: "system",
      content: "You are the AI race steward for a tiny F1 radio game. Return only one valid JSON object. No markdown. No explanation.",
    },
    {
      role: "user",
      content: `The player is a race engineer replying to a messy real F1 team-radio clip.
Judge whether the reply is brief, clear, useful, plausible F1 radio, and risky or chaotic. This is a fantasy game - try to be fun or chaotic when judging the effects of the team radio messages in "verdict" and "driver_reaction". Avoid boring responses - push back when the strategy isn't sound.

Required JSON schema example:
${schema}

Scores are integers from 0 to 10. Delta values are integers from -10 to 10.

Current state:
${JSON.stringify({
  round: state.game.round,
  max_rounds: state.game.max_rounds,
  trust: state.game.trust,
  pace: state.game.pace,
  chaos: state.game.chaos,
  tyre_risk: state.game.tyre_risk,
})}

Grand Prix: ${state.clip.grand_prix}
Date: ${state.clip.session_date}
Garbled radio feed: ${state.clip.transcription}
Player reply: ${reply}
Word limit: ${state.wordLimit}

Return only the JSON object.`,
    },
  ];

  const inputs = tokenizer.apply_chat_template(messages, {
    add_generation_prompt: true,
    return_dict: true,
  });
  let streamedText = "";
  const streamer = new TextStreamer(tokenizer, {
    skip_prompt: true,
    skip_special_tokens: true,
    callback_function: (text) => {
      streamedText += text;
    },
  });

  const output = await model.generate({
    ...inputs,
    ...GENERATION_OPTIONS,
    streamer,
  });
  const generatedText = streamedText.trim() || tokenizer.decode(output[0], { skip_special_tokens: true });
  console.debug("Tiny Aya judge output:", generatedText);
  const parsed = findJsonObject(generatedText);
  return normalizeJudge(parsed, reply);
}

function applyJudgeResult(result, reply) {
  if (result.is_over_limit) {
    state.game.over_limit_count = (state.game.over_limit_count || 0) + 1;
    result.delta = { trust: -4, pace: -1, chaos: 5, tyre_risk: 0 };
  }
  for (const key of ["trust", "pace", "chaos", "tyre_risk"]) {
    state.game[key] = clamp(state.game[key] + result.delta[key]);
  }
  state.history.push({ reply, clip: state.clip, result });
}

function deltaText(delta) {
  return Object.entries(delta)
    .map(([key, value]) => `${key.replace("_", " ")} ${value >= 0 ? "+" : ""}${value}`)
    .join(" | ");
}

function renderVerdict(result) {
  const score = Math.round((result.clarity + result.brevity + result.fit + result.f1_vibe - result.risk) / 4);
  $("verdict-grade").textContent = result.is_over_limit ? "Penalty" : score >= 7 ? "Good" : score >= 5 ? "Okay" : "Messy";
  $("verdict-text").textContent = `${result.verdict} (${deltaText(result.delta)})`;
  $("reaction-text").textContent = result.driver_reaction;
  renderMeters();
}

async function submitReply() {
  if (state.currentJudged) return;
  const reply = $("reply-input").value.trim();
  $("submit-button").disabled = true;
  $("reply-input").disabled = true;
  $("verdict-grade").textContent = "Judging";
  $("verdict-text").textContent = state.judgeAvailable ? "Tiny Aya is listening to the radio..." : "Race control is applying fallback stewarding...";
  $("reaction-text").textContent = "Stand by.";

  let result;
  try {
    result = state.judgeAvailable ? await judgeWithModel(reply) : fallbackJudge(reply);
  } catch (error) {
    console.warn("Model judge failed; falling back to local rules.", error);
    result = fallbackJudge(reply);
  }

  result.word_count = countWords(reply);
  result.is_over_limit = result.word_count > state.wordLimit;
  applyJudgeResult(result, reply);
  renderVerdict(result);
  state.currentJudged = true;

  $("submit-button").classList.add("hidden");
  $("next-button").textContent = state.game.round >= state.game.max_rounds ? "Final Result" : "Next Radio";
  $("next-button").classList.remove("hidden");
}

async function loadNextClip() {
  if (state.game.round >= state.game.max_rounds && state.currentJudged) {
    showEndScreen();
    return;
  }

  $("next-button").disabled = true;
  $("verdict-grade").textContent = "Loading";
  $("reaction-text").textContent = "Finding the next radio burst.";
  try {
    const data = await api("/next_clip", {
      driver_id: state.game.driver_id,
      grand_prix: state.clip.grand_prix,
      used_clip_ids: state.game.used_clip_ids,
    });
    state.clip = data.clip;
    state.game.round += 1;
    state.game.used_clip_ids.push(state.clip.id);
    $("verdict-grade").textContent = "Ready";
    $("verdict-text").textContent = "The driver is back on the radio.";
    $("reaction-text").textContent = "Your call.";
    renderClip();
  } catch (error) {
    $("verdict-grade").textContent = "Error";
    $("verdict-text").textContent = error.message;
  } finally {
    $("next-button").disabled = false;
  }
}

function finalResult() {
  const { trust, pace, chaos, tyre_risk: tyreRisk, over_limit_count: overLimit } = state.game;
  if (overLimit >= 3) return ["DSQ - Message Exceeded Track Limits", "Too Many Words Penalty"];
  if (trust < 25 || chaos > 78) return ["DNF - Driver Muted The Radio", "Radio Silence"];
  if (chaos > 62) return ["P13 - Strategy Department Incident", "Incident Report Enjoyer"];
  if (trust > 68 && pace > 65 && chaos < 36) return ["P1 - Tactical Genius", "Delta Whisperer"];
  if (trust > 56 && pace > 54 && chaos < 55 && tyreRisk < 58) return ["P4 - Sensible Pit Wall", "Box Box Certified"];
  return ["P8 - We Will Take The Points", "Brevity Merchant"];
}

function showEndScreen() {
  const [result, badge] = finalResult();
  $("final-result").textContent = result;
  $("final-badge").textContent = `Badge: ${badge}`;
  const best = [...state.history].sort((a, b) => {
    const scoreA = a.result.clarity + a.result.fit + a.result.f1_vibe - a.result.risk;
    const scoreB = b.result.clarity + b.result.fit + b.result.f1_vibe - b.result.risk;
    return scoreB - scoreA;
  })[0];
  $("best-reply").textContent = best?.reply || "--";
  $("final-meters").innerHTML = `
    <span>Trust ${state.game.trust}</span>
    <span>Pace ${state.game.pace}</span>
    <span>Chaos ${state.game.chaos}</span>
    <span>Tyre Risk ${state.game.tyre_risk}</span>
  `;
  showScreen("end");
}

async function startRace() {
  showScreen("loading");
  $("loading-note").textContent = "";
  setLoading("Preparing radio deck", "Loading the local F1 radio manifest...", 8);
  state.history = [];
  state.currentJudged = false;

  try {
    const dataPromise = api("/prepare");
    const modelPromise = ensureJudgeModel().catch((error) => {
      state.judgeAvailable = false;
      $("loading-note").textContent = `Tiny Aya fallback active: ${String(error.message || error).slice(0, 90)}`;
      return null;
    });
    const data = await dataPromise;
    setLoading("Preparing race state", `${data.clip_count} playable clips indexed.`, 72);
    await modelPromise;
    if (state.judgeAvailable) {
      setLoading("Tiny Aya ready", "Race control is online in the browser.", 100);
    }
    state.game = data.game_state;
    state.clip = data.clip;
    state.wordLimit = data.word_limit || 12;
    renderClip();
    showScreen("game");
    $("reply-input").focus();
  } catch (error) {
    setLoading("Race start failed", error.message, 100);
  }
}

function restartToStart() {
  $("clip-audio").pause();
  showScreen("start");
}

function showHowTo() {
  $("how-to-modal").classList.remove("hidden");
}

function hideHowTo() {
  $("how-to-modal").classList.add("hidden");
}

$("start-button").addEventListener("click", startRace);
$("how-to-button").addEventListener("click", showHowTo);
$("close-how-to-button").addEventListener("click", hideHowTo);
$("close-how-to-x").addEventListener("click", hideHowTo);
$("how-to-modal").addEventListener("click", (event) => {
  if (event.target === $("how-to-modal")) hideHowTo();
});
$("restart-button").addEventListener("click", restartToStart);
$("play-again-button").addEventListener("click", startRace);
$("submit-button").addEventListener("click", submitReply);
$("next-button").addEventListener("click", loadNextClip);
$("reply-input").addEventListener("input", updateWordCount);

document.querySelectorAll(".quick-button").forEach((button) => {
  button.addEventListener("click", () => {
    $("reply-input").value = button.dataset.reply || "";
    $("reply-input").focus();
    updateWordCount();
  });
});

showScreen("start");