// GODSEED — main page. Boot the planet, wire the HUD, then either:
//   live  : GET /api/state → EventSource /api/stream (SSE protocol)
//   mock  : ?mock=1 → web/mock/world.json + scripted looping wish feed
// The deterministic engine owns the facts; this file only performs them.
import { createPlanetApp } from "./planet/scene.js";
import { buildWishScript, ScriptRunner } from "./planet/replay.js";
import { latLonToDir, PLANET_R, ordinal, clamp, townCenter } from "./planet/util.js";

const params = new URLSearchParams(location.search);
const MOCK = params.has("mock");
const STATIC = params.has("static");
const UPTO = params.has("upto") ? Math.max(0, parseInt(params.get("upto"), 10) || 0) : null;

// ---------------------------------------------------------------- HUD
const els = {
  epoch: document.getElementById("epoch"),
  voiceDot: document.getElementById("voiceDot"),
  voiceWish: document.getElementById("voiceWish"),
  stream: document.getElementById("voiceStream"),
  epitaph: document.getElementById("epitaph"),
  epitaphText: document.getElementById("epitaphText"),
  epitaphLabel: document.getElementById("epitaphLabel"),
  epitaphDescend: document.getElementById("epitaphDescend"),
  queueChip: document.getElementById("queueChip"),
  form: document.getElementById("wishForm"),
  input: document.getElementById("wishInput"),
  send: document.getElementById("wishSend"),
  hint: document.getElementById("altarHint"),
  status: document.getElementById("status"),
  behold: document.getElementById("beholdToggle"),
};

const HINT_DEFAULT = "the god grants one wish at a time";
let hintTimer = null;
function hint(text, { warn = false, revert = 6000 } = {}) {
  els.hint.textContent = text;
  els.hint.classList.toggle("is-warn", warn);
  clearTimeout(hintTimer);
  if (revert) {
    hintTimer = setTimeout(() => {
      els.hint.textContent = HINT_DEFAULT;
      els.hint.classList.remove("is-warn");
    }, revert);
  }
}

const caret = document.createElement("span");
caret.className = "voice__caret";

function tickerClear() {
  els.stream.innerHTML = "";
}
function tickerPush(text, tone = "thought") {
  caret.remove();
  let inner = els.stream.querySelector(".voice__innertext");
  if (!inner) {
    inner = document.createElement("span");
    inner.className = "voice__innertext";
    els.stream.appendChild(inner);
  }
  const span = document.createElement("span");
  span.className = `tone-${tone}`;
  span.textContent = text;
  inner.appendChild(span);
  inner.appendChild(caret);
  while (inner.children.length > 420) inner.firstChild.remove();
}
function tickerIdle() {
  caret.remove();
  els.voiceDot.classList.remove("is-live");
}
function tickerLive(wishText) {
  els.voiceDot.classList.add("is-live");
  els.voiceWish.textContent = wishText ? `“${wishText}”` : "";
}

let epitaphTimer = null;
function showEpitaph(text, label = "the wish is granted") {
  els.epitaphText.textContent = text;
  els.epitaphLabel.textContent = label;
  els.epitaph.classList.add("is-shown");
  clearTimeout(epitaphTimer);
  // hold long enough for the eye to find the "descend ↓" affordance
  epitaphTimer = setTimeout(() => {
    els.epitaph.classList.remove("is-shown");
    if (els.epitaphDescend) els.epitaphDescend.hidden = true;
  }, 9000);
}

function setEpoch(epoch, granted = epoch) {
  els.epoch.textContent = `Epoch ${epoch} · ${granted} ${granted === 1 ? "wish" : "wishes"} granted`;
}

function setQueue(length, mine = null) {
  if (mine != null) {
    els.queueChip.hidden = false;
    els.queueChip.textContent = `your wish is ${ordinal(mine)} in line`;
  } else if (length > 0) {
    els.queueChip.hidden = false;
    els.queueChip.textContent = `${length} ${length === 1 ? "wish waits" : "wishes wait"}`;
  } else {
    els.queueChip.hidden = true;
  }
}

function fmtCall(call) {
  const a = call.args || {};
  const bits = [];
  if (a.kind) bits.push(a.kind);
  if (a.palette) bits.push(a.palette);
  if (a.lat != null) bits.push(`${(+a.lat).toFixed(0)}°, ${(+a.lon).toFixed(0)}°`);
  if (a.path) bits.push(`${a.path.length} waypoints`);
  if (a.radius_deg != null) bits.push(`r ${(+a.radius_deg).toFixed(0)}°`);
  if (a.height != null) bits.push(`h ${a.height}`);
  if (a.depth != null) bits.push(`d ${a.depth}`);
  if (a.intensity != null) bits.push(`i ${a.intensity}`);
  if (a.moons != null) bits.push(`${a.moons} moon${a.moons === 1 ? "" : "s"}`);
  if (a.style) bits.push(a.style);
  return `\n⟡ ${call.tool} · ${bits.join(" · ")}\n`;
}

function callTarget(call) {
  const a = call.args || {};
  if (call.tool === "set_sky" || call.tool === "set_weather") return null;
  if (call.tool === "inscribe_wish") return null; // delta will refine (stone seats by seed)
  if (a.path && a.path.length) return latLonToDir(a.path[0][0], a.path[0][1]).multiplyScalar(PLANET_R);
  if (a.lat != null && a.lon != null) return latLonToDir(a.lat, a.lon).multiplyScalar(PLANET_R);
  return null;
}

// The direction on the surface a feature landed at (for the descent target).
// Sky/weather have no place, so they don't count toward "where to visit".
function featureDir(feature) {
  const a = feature?.args || {};
  if (feature?.tool === "set_sky" || feature?.tool === "set_weather") return null;
  if (a.path && a.path.length) return latLonToDir(a.path[0][0], a.path[0][1]);
  if (a.lat != null && a.lon != null) return latLonToDir(a.lat, a.lon);
  return null;
}

// "descend ↓" affordance on the epitaph card → swoop down over the wish site.
function armDescent(dir) {
  if (!els.epitaphDescend) return;
  if (dir) {
    lastDescentDir = dir.clone();
    els.epitaphDescend.hidden = false;
  } else if (!lastDescentDir) {
    els.epitaphDescend.hidden = true;
  }
}

// ---------------------------------------------------------------- boot
let app;
try {
  app = createPlanetApp(document.getElementById("scene"), { interactive: true });
} catch (err) {
  els.status.textContent = "this vessel cannot hold the world (WebGL unavailable)";
  console.error(err);
  throw err;
}

// last surface direction a wish landed at — the descent target.
let lastDescentDir = null;
if (els.epitaphDescend) {
  els.epitaphDescend.addEventListener("click", () => {
    if (!lastDescentDir) return;
    app.rig.setTerrain?.(app.world.terrain); // clear live terrain analytically
    app.rig.descend(lastDescentDir.clone().multiplyScalar(PLANET_R));
  });
}

// Re-anchor the town heart from the current world (camera follows it as it
// densifies). Called on every state load + world_delta.
function syncTown() {
  app.rig.setTownCenter(app.world.features);
}

// "behold the world ↕" — pull back to the full planet; "↻ return to the town" —
// drop back into the close town view. Reflects the rig's current mode.
function updateBeholdLabel() {
  if (!els.behold) return;
  const world = app.rig.mode === "world";
  els.behold.classList.toggle("is-world", world);
  els.behold.setAttribute("aria-pressed", world ? "true" : "false");
  els.behold.querySelector(".behold__label").textContent =
    world ? "return to the town" : "behold the world";
}
if (els.behold) {
  els.behold.addEventListener("click", () => {
    app.rig.beholdWorld();
    updateBeholdLabel();
  });
  updateBeholdLabel();
}

const featuresByWish = (features, upto) => {
  if (upto == null) return features;
  const order = [];
  const seen = new Set();
  for (const f of features) {
    if (!seen.has(f.wish_id)) { seen.add(f.wish_id); order.push(f.wish_id); }
  }
  const keep = new Set(order.slice(0, upto + 1)); // genesis is index 0
  return features.filter((f) => keep.has(f.wish_id));
};

function applyDevOverrides() {
  if (params.has("sky")) {
    app.world.sky.set(params.get("sky"), parseFloat(params.get("stars") ?? "0.8"),
      parseInt(params.get("moons") ?? "1", 10), { animate: false });
  }
  if (params.has("weather")) {
    app.world.weather.set(params.get("weather"), parseFloat(params.get("wi") ?? "0.6"), { animate: false });
  }
}

function countWishes(features) {
  const s = new Set();
  for (const f of features) if (f.wish_id !== "genesis") s.add(f.wish_id);
  return s.size;
}

// ---------------------------------------------------------------- live mode
async function bootLive() {
  let stateVersion = null;
  let readingPhase = true;

  async function loadState() {
    const res = await fetch("/api/state");
    if (!res.ok) throw new Error(`state ${res.status}`);
    const state = await res.json();
    stateVersion = state.world?.version ?? null;
    app.world.reset(state.world?.features ?? [], app.simTime);
    syncTown(); // anchor the town heart, then frame it (the default close view)
    const epoch = state.world?.epoch ?? countWishes(state.world?.features ?? []);
    setEpoch(epoch, epoch);
    setQueue(state.queue?.length ?? 0);
    return state;
  }

  try {
    await loadState();
    els.status.textContent = "live · the god is listening";
  } catch (err) {
    console.warn("no live backend:", err);
    els.status.textContent = "the god is dreaming · demo vision";
    return bootMock(); // graceful fall-back to the mock world
  }

  // Browser-invoked granting (ZeroGPU): the GPU rite must run inside OUR
  // gradio request so the HF auth headers carry the quota. When the SSE says
  // it's our wish's turn, call the named gradio endpoint with the one-time token.
  const myWishes = new Set();
  // your_turn can arrive BEFORE the POST response registers our wish_id (an
  // empty queue turns to a wish instantly) — buffer unmatched turns and replay
  // them the moment the wish registers.
  const pendingTurns = new Set();
  let gradioClient = null;
  async function invokeGrant(wishId) {
    els.status.textContent = "the god turns to your wish…";
    try {
      // Fetch our secret token from the cookie-authenticated route — it is
      // never broadcast over SSE, so only the wish's owner can begin the rite.
      const tr = await fetch(`/api/turn?wish_id=${encodeURIComponent(wishId)}`, {
        credentials: "same-origin",
      });
      if (!tr.ok) {
        if (tr.status === 403) return; // not our turn (a stranger's wish)
        throw new Error(`turn ${tr.status}`);
      }
      const { token } = await tr.json();
      if (!gradioClient) {
        const { Client } = await import("https://cdn.jsdelivr.net/npm/@gradio/client/+esm");
        gradioClient = await Client.connect(window.location.origin);
      }
      const r = await gradioClient.predict("/grant", { wish_id: wishId, token });
      const out = Array.isArray(r?.data) ? r.data[0] : r?.data;
      if (out && out.ok === false && out.reason) hint(out.reason, { warn: true });
    } catch (err) {
      console.error("grant invocation failed", err);
      hint("the rite could not begin — sign in to hugging face, then wish again", { warn: true });
    }
  }

  const es = new EventSource("/api/stream");
  es.onmessage = (e) => {
    let m;
    try { m = JSON.parse(e.data); } catch { return; }
    switch (m.type) {
      case "your_turn":
        if (myWishes.has(m.wish_id)) invokeGrant(m.wish_id);
        else pendingTurns.add(m.wish_id);
        break;
      case "hello":
        if (stateVersion != null && m.world_version !== stateVersion) loadState().catch(() => {});
        if (m.epoch != null) setEpoch(m.epoch, m.epoch);
        break;
      case "queue":
        setQueue(m.length ?? 0);
        if (m.current?.text_preview) tickerLive(m.current.text_preview);
        break;
      case "wish_started":
        tickerClear();
        readingPhase = true;
        tickerLive(m.text);
        lastDescentDir = null;
        if (els.epitaphDescend) els.epitaphDescend.hidden = true;
        break;
      case "thought_token":
        tickerPush(m.text, readingPhase ? "reading" : "thought");
        break;
      case "tool_call": {
        readingPhase = false;
        tickerPush(fmtCall(m), "call");
        app.rig.gaze(callTarget(m), { hold: 5 });
        break;
      }
      case "world_delta": {
        if (m.feature) {
          stateVersion = stateVersion == null ? null : stateVersion + 1;
          const cue = app.world.applyFeature(m.feature, { animate: true, t: app.simTime });
          // a new building shifts the town's heart — re-anchor before framing so
          // the camera follows the town as it densifies (no-op for sky/weather).
          if (m.feature.tool === "place_structure" || m.feature.tool === "build_district") {
            syncTown();
          }
          // gaze toward where the world is actually changing — the cue target is
          // the resolved surface point (refines inscriptions/structures by seed).
          // In TOWN mode gaze() keeps this WITHIN the town zoom (never the far limb).
          if (cue.target) app.rig.gaze(cue.target.clone().multiplyScalar(PLANET_R), { hold: 5.5 });
          else if (cue.wide) app.rig.gaze(null, { hold: 4 });
          const dir = cue.target || featureDir(m.feature);
          if (dir) lastDescentDir = dir.clone().normalize();
        }
        break;
      }
      case "wish_granted":
        showEpitaph(m.epitaph || "it is made");
        if (m.epoch != null) setEpoch(m.epoch, m.epoch);
        app.world.sky.flash(0.35);
        armDescent(lastDescentDir);
        // hold a beat on the wish site, THEN release to the wide shot
        if (lastDescentDir && !app.rig.descending) {
          app.rig.gaze(lastDescentDir.clone().multiplyScalar(PLANET_R), { hold: 3.6 });
        } else {
          app.rig.release();
        }
        tickerIdle();
        els.status.textContent = "live · the god is listening";
        break;
      case "wish_rejected":
        hint(m.reason || "the god declines this wish.", { warn: true });
        tickerIdle();
        break;
      case "heartbeat":
        break;
    }
  };
  es.onerror = () => {
    els.status.textContent = "the link to the god flickers · reconnecting";
  };
  es.addEventListener("open", () => {
    els.status.textContent = "live · the god is listening";
  });

  // wish submission
  els.form.addEventListener("submit", async (e) => {
    e.preventDefault();
    const text = els.input.value.trim();
    if (!text) return;
    els.send.disabled = true;
    try {
      const res = await fetch("/api/wish", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ text }),
      });
      const body = await res.json().catch(() => ({}));
      if (res.ok) {
        els.input.value = "";
        if (body.wish_id) {
          myWishes.add(body.wish_id);
          if (pendingTurns.has(body.wish_id)) {
            pendingTurns.delete(body.wish_id);
            invokeGrant(body.wish_id);
          }
        }
        setQueue(body.position ?? 1, body.position ?? 1);
        hint("the god has heard you — stay; your presence completes the rite", { revert: 6000 });
      } else {
        hint(body.reason || body.detail || "the god declines this wish.", { warn: true });
      }
    } catch {
      hint("the offering was lost — try again", { warn: true });
    } finally {
      els.send.disabled = false;
    }
  });
}

// ---------------------------------------------------------------- mock mode
let mockApi = {};
async function bootMock() {
  const [state, { FEED_WISH }] = await Promise.all([
    fetch("./mock/world.json").then((r) => r.json()),
    import("./mock/feed.js"),
  ]);
  const baseFeatures = featuresByWish(state.world.features, UPTO);
  const baseEpoch = countWishes(baseFeatures);
  app.world.reset(baseFeatures, app.simTime);
  syncTown();           // anchor + frame the town heart (the default close view)
  applyDevOverrides();
  setEpoch(baseEpoch, baseEpoch);
  els.status.textContent = MOCK ? "demo vision · ?mock=1" : "the god is dreaming · demo vision";
  const looping = !STATIC && UPTO == null;

  // -- looping scripted feed: one full wish, replayed forever ------------
  const runner = new ScriptRunner({
    started: (e) => { tickerClear(); tickerLive(e.text); },
    phase: () => {},
    token: (e) => {
      const tone = e.text.startsWith("\n›") ? "obs" : phase === "reading" ? "reading" : "thought";
      tickerPush(e.text, tone);
    },
    call: (e) => {
      phase = "turn";
      tickerPush(fmtCall(e.call), "call");
      app.rig.gaze(callTarget(e.call), { hold: 4.5 });
    },
    delta: (e) => {
      const cue = app.world.applyFeature(e.feature, { animate: true, t: app.simTime });
      if (e.feature.tool === "place_structure" || e.feature.tool === "build_district") {
        syncTown(); // the town heart follows each new building
      }
      if (cue.target) app.rig.gaze(cue.target.clone().multiplyScalar(PLANET_R), { hold: 4.5 });
      else if (cue.wide) app.rig.gaze(null, { hold: 3.5 });
      const dir = cue.target || featureDir(e.feature);
      if (dir) lastDescentDir = dir.clone().normalize();
    },
    granted: (e) => {
      showEpitaph(e.epitaph);
      setEpoch(baseEpoch + 1, baseEpoch + 1);
      app.world.sky.flash(0.35);
      armDescent(lastDescentDir);
      if (lastDescentDir && !app.rig.descending) {
        app.rig.gaze(lastDescentDir.clone().multiplyScalar(PLANET_R), { hold: 3.6 });
      } else {
        app.rig.release();
      }
      tickerIdle();
      cooldown = 12; // dwell on the granted world (descend affordance) before reset
    },
  });
  let phase = "reading";
  let cooldown = 7; // contemplative pause before the first / between loops
  let pendingWishText = null;

  function startFeed(customText) {
    phase = "reading";
    lastDescentDir = null;
    if (els.epitaphDescend) els.epitaphDescend.hidden = true;
    const trace = customText ? { ...FEED_WISH.trace, text: customText } : FEED_WISH.trace;
    runner.start(buildWishScript(trace, FEED_WISH.features), app.simTime);
  }

  app.onTick((t, dt) => {
    runner.update(t);
    if (!looping || runner.active) return;
    cooldown -= dt;
    if (cooldown <= 0) {
      // reset to the base world, then perform the wish again — determinism on display
      if (app.world.features.length > baseFeatures.length) {
        app.world.reset(baseFeatures, t);
        syncTown(); // back to the base town heart before the wish runs again
        setEpoch(baseEpoch, baseEpoch);
        tickerClear();
        tickerIdle();
        els.voiceWish.textContent = "";
      }
      startFeed(pendingWishText);
      if (pendingWishText) { setQueue(0); pendingWishText = null; }
      cooldown = 10;
    }
  });

  if (looping) {
    els.form.addEventListener("submit", (e) => {
      e.preventDefault();
      const text = els.input.value.trim();
      if (!text) return;
      pendingWishText = text.slice(0, 140);
      els.input.value = "";
      setQueue(0, 1);
      hint("demo vision — the god will dream your words", { revert: 7000 });
    });
  }

  mockApi.runFeedOnce = startFeed;
  mockApi.resetTo = (upto) => {
    runner.cancel();
    const feats = featuresByWish(state.world.features, upto ?? null);
    app.world.reset(feats, app.simTime);
    setEpoch(countWishes(feats), countWishes(feats));
  };
}

// ---------------------------------------------------------------- start
const ready = (MOCK ? bootMock() : bootLive())
  .then(() => { window.__godseed.ready = true; })
  .catch((err) => {
    els.status.textContent = "the vision failed to load";
    console.error(err);
  });
app.start();

// status heartbeat (epoch + sky, quiet diagnostics)
setInterval(() => {
  const s = app.stats();
  // base = everything that isn't a previous "<palette> sky" suffix (the status
  // text varies between 1 and 2 segments; a fixed slice duplicated the suffix)
  const base = els.status.textContent
    .split(" · ")
    .filter((p) => !p.trim().endsWith(" sky"))
    .join(" · ");
  els.status.textContent = `${base} · ${s.sky} sky`;
}, 4000);

// ---------------------------------------------------------------- harness API
window.__godseed = {
  ready: false,
  app,
  get world() { return app.world; },
  get rig() { return app.rig; },
  tick: (seconds) => app.tick(seconds),
  seek: (t) => app.seek(t),
  pause: (v) => app.pause(v),
  stats: () => app.stats(),
  gazeLatLon: (lat, lon, hold = 30) => {
    app.rig.userHold = 0;
    app.rig.gaze(latLonToDir(lat, lon).multiplyScalar(PLANET_R), { hold });
  },
  gazeWide: () => { app.rig.setMode("world"); updateBeholdLabel(); },
  setMode: (mode) => { app.rig.setMode(mode); updateBeholdLabel(); },
  beholdWorld: () => { const m = app.rig.beholdWorld(); updateBeholdLabel(); return m; },
  townCenter: () => townCenter(app.world.features),
  descend: (lat, lon, duration = 13) => {
    app.rig.setTerrain?.(app.world.terrain);
    app.rig.descend(latLonToDir(lat, lon).multiplyScalar(PLANET_R), { duration });
  },
  descendLast: (duration = 13) => {
    if (!lastDescentDir) return false;
    app.rig.setTerrain?.(app.world.terrain);
    app.rig.descend(lastDescentDir.clone().multiplyScalar(PLANET_R), { duration });
    return true;
  },
  setSky: (p, stars = 0.8, moons = 1) => app.world.sky.set(p, stars, moons, { animate: false }),
  setWeather: (k, i = 0.6) => app.world.weather.set(k, i, { animate: false }),
  setCamera: (theta, phi, dist) => {
    Object.assign(app.rig, {
      theta, thetaT: theta, phi, phiT: phi,
      dist: dist ?? app.rig.dist, distT: dist ?? app.rig.distT,
    });
  },
  runFeedOnce: (text) => mockApi.runFeedOnce?.(text),
  resetTo: (n) => mockApi.resetTo?.(n),
};