import { CONFIG } from "./config.js";
import { costAt, rateText } from "./cost.js";
import * as hf from "./hf.js";

const CAT_COLORS = { code: "#3b82f6", general: "#f97316", cyber: "#10b981", visual: "#f59e0b", chat: "#ec4899" };
const RUN_COLORS = { pro: "#f0643c", flash: "#3b82f6" };
const UNITS = ["second", "minute", "hour", "day", "month", "year"];

const state = {
  data: null,
  error: null,
  authError: null,
  lastSync: null,
  tab: "overview",
  token: null,
  me: null,
  isAdmin: false,
  dirty: false,
  saveStatus: "",
  saveFailed: false,
  jsonDraft: null,
  jsonError: "",
  ui: { xMode: "step", yLog: false, smooth: 0, compMode: "count" },
};

let chartSeq = 0;
const chartStore = {};

/* ---------- helpers ---------- */

const $ = (sel) => document.querySelector(sel);
const esc = (s) =>
  String(s ?? "").replace(/[&<>"']/g, (c) => ({ "&": "&amp;", "<": "&lt;", ">": "&gt;", '"': "&quot;", "'": "&#39;" }[c]));

const fmtInt = (n) => (n == null || isNaN(n) ? "—" : Math.round(n).toLocaleString("en-US"));
const fmtMoney = (n) => "$" + fmtInt(n);

function fmtNum(v) {
  if (v == null || isNaN(v)) return "—";
  const a = Math.abs(v);
  if (a >= 1000) return Math.round(v).toLocaleString("en-US");
  if (a >= 1) return v.toFixed(2);
  if (a === 0) return "0";
  return v.toPrecision(3);
}

function fmtBig(n) {
  if (n == null || isNaN(n)) return "—";
  const a = Math.abs(n);
  if (a >= 1e9) return (n / 1e9).toFixed(2) + "B";
  if (a >= 1e6) return (n / 1e6).toFixed(1) + "M";
  if (a >= 1e3) return (n / 1e3).toFixed(0) + "k";
  return String(Math.round(n));
}

function fmtUtc(iso) {
  const d = new Date(iso);
  return isNaN(d) ? "—" : d.toISOString().slice(0, 16).replace("T", " ") + " UTC";
}

function fmtTime(t) {
  return isNaN(Date.parse(t)) ? String(t ?? "") : fmtUtc(t);
}

function fmtDuration(ms) {
  if (isNaN(ms)) return "—";
  const s = Math.max(0, Math.floor(ms / 1000));
  const d = Math.floor(s / 86400);
  const h = String(Math.floor((s % 86400) / 3600)).padStart(2, "0");
  const m = String(Math.floor((s % 3600) / 60)).padStart(2, "0");
  const sec = String(s % 60).padStart(2, "0");
  return `${d}d ${h}:${m}:${sec}`;
}

const last = (vals) => (vals || []).filter((v) => v != null).slice(-1)[0];
const runName = (k) => state.data?.runs?.find((r) => r.id === k)?.name ?? k;
const runColor = (k) => state.data?.runs?.find((r) => r.id === k)?.color ?? RUN_COLORS[k] ?? "#888";
const costNow = () => (state.data ? costAt(state.data.cost, Date.now()) : 0);

function metricLast(group, name, runId) {
  const m = state.data.metrics.find((x) => x.group === group && x.name === name);
  return m ? last(m.series[runId]) : undefined;
}

function delta(vals) {
  const v = (vals || []).filter((x) => x != null);
  if (v.length < 2) return "";
  const a = v[v.length - 1];
  const b = v[v.length - 2];
  if (v.every((x) => x >= 0 && x <= 1)) {
    const d = (a - b) * 100;
    return `${d >= 0 ? "▲" : "▼"} ${Math.abs(d).toFixed(2)} pt`;
  }
  const p = b ? ((a - b) / Math.abs(b)) * 100 : 0;
  return `${p >= 0 ? "▲" : "▼"} ${Math.abs(p).toFixed(1)}%`;
}
const deltaClass = (vals) => (delta(vals).startsWith("▲") ? "up" : "down");

function smooth(vals, w) {
  if (w <= 1) return vals;
  return vals.map((_, i) => {
    const s = vals.slice(Math.max(0, i - w + 1), i + 1).filter((v) => v != null);
    return s.length ? s.reduce((x, y) => x + y, 0) / s.length : null;
  });
}

// Hours per training step, used for the "time" x-axis option.
function stepHours() {
  const r = state.data?.runs?.find((x) => x.step > 0 && x.startedAt);
  if (!r) return 1;
  const end = r.stoppedAt ? Date.parse(r.stoppedAt) : Date.now();
  return (end - Date.parse(r.startedAt)) / 3600000 / r.step;
}

function xLabel(i) {
  return state.ui.xMode === "time" ? (i * stepHours()).toFixed(1) + "h" : String(i + 1);
}

/* ---------- charts ---------- */

function chartSvg(series) {
  const n = Math.max(0, ...series.map((s) => s.values.length));
  const logOn = state.ui.yLog;
  const ser = series.map((s) => ({ ...s, values: smooth(s.values, state.ui.smooth) }));
  const ok = (v) => v != null && !isNaN(v) && (!logOn || v > 0);
  const tv = (v) => (logOn ? Math.log10(v) : v);
  const flat = ser.flatMap((s) => s.values.filter(ok));
  if (n < 2 || !flat.length) return `<div class="empty">no data</div>`;

  let lo = tv(Math.min(...flat));
  let hi = tv(Math.max(...flat));
  if (hi - lo < 1e-9) { lo -= 1; hi += 1; }
  const pad = (hi - lo) * 0.08;
  lo -= pad;
  hi += pad;

  const W = 600, H = 220, pl = 48, pr = 12, pt = 10, pb = 24;
  const X = (i) => pl + ((W - pl - pr) * i) / (n - 1);
  const Y = (v) => pt + (H - pt - pb) * (1 - (tv(v) - lo) / (hi - lo));
  const inv = (t) => (logOn ? 10 ** t : t);

  let grid = "";
  for (let k = 0; k <= 4; k++) {
    const y = pt + (H - pt - pb) * (1 - k / 4);
    const val = inv(lo + ((hi - lo) * k) / 4);
    grid += `<line class="grid" x1="${pl}" x2="${W - pr}" y1="${y}" y2="${y}"/>`;
    grid += `<text x="${pl - 6}" y="${y + 4}" text-anchor="end">${fmtNum(val)}</text>`;
  }

  const labels = Array.from({ length: n }, (_, i) => xLabel(i));
  let xl = "";
  for (let k = 0; k <= 4; k++) {
    const i = Math.round(((n - 1) * k) / 4);
    xl += `<text x="${X(i)}" y="${H - 6}" text-anchor="middle">${labels[i]}</text>`;
  }

  const paths = ser
    .map((s) => {
      let d = "";
      let pen = false;
      s.values.forEach((v, i) => {
        if (!ok(v)) { pen = false; return; }
        d += (pen ? "L" : "M") + X(i).toFixed(1) + " " + Y(v).toFixed(1) + " ";
        pen = true;
      });
      return `<path d="${d}" fill="none" stroke="${s.color}" stroke-width="1.8"/>`;
    })
    .join("");

  const id = "c" + ++chartSeq;
  chartStore[id] = { ser, labels, n, W, pl, pr };
  return `<svg class="chart" data-chart="${id}" viewBox="0 0 ${W} ${H}">${grid}${xl}${paths}</svg>`;
}

function stackedSvg(cats) {
  const keys = Object.keys(cats);
  const n = Math.max(0, ...keys.map((k) => cats[k].length));
  if (!n) return `<div class="empty">no data</div>`;
  const totals = Array.from({ length: n }, (_, i) => keys.reduce((s, k) => s + (cats[k][i] || 0), 0));
  const share = state.ui.compMode === "share";
  const W = 600, H = 220, pl = 48, pt = 10, pb = 24;
  const max = share ? 1 : Math.max(...totals) || 1;
  const bw = (W - pl) / n;

  let bars = "";
  for (let i = 0; i < n; i++) {
    let acc = 0;
    for (const k of keys) {
      const raw = cats[k][i] || 0;
      const v = share ? (totals[i] ? raw / totals[i] : 0) : raw;
      const h = ((H - pt - pb) * v) / max;
      bars += `<rect x="${(pl + i * bw + 1).toFixed(1)}" y="${(H - pb - acc - h).toFixed(1)}" width="${(bw - 2).toFixed(1)}" height="${h.toFixed(1)}" fill="${CAT_COLORS[k] || "#888"}"><title>step ${i + 1} · ${k}: ${fmtInt(raw)}</title></rect>`;
      acc += h;
    }
  }
  const ticks = [0, 0.5, 1]
    .map((f) => {
      const y = pt + (H - pt - pb) * (1 - f);
      const label = share ? Math.round(f * 100) + "%" : fmtInt(max * f);
      return `<line class="grid" x1="${pl}" x2="${W}" y1="${y}" y2="${y}"/><text x="${pl - 6}" y="${y + 4}" text-anchor="end">${label}</text>`;
    })
    .join("");
  const xl = [0, Math.floor((n - 1) / 2), n - 1]
    .map((i) => `<text x="${pl + i * bw + bw / 2}" y="${H - 6}" text-anchor="middle">${i + 1}</text>`)
    .join("");
  return `<svg class="chart" viewBox="0 0 ${W} ${H}">${ticks}${bars}${xl}</svg>`;
}

function legendHtml(series, showDelta = false) {
  return `<div class="legend">${series
    .map(
      (s) => `<span><i style="background:${s.color}"></i>${esc(s.name)} <b class="mono">${fmtNum(last(s.values))}</b>${
        showDelta ? ` <span class="mono ${deltaClass(s.values)}">${delta(s.values)}</span>` : ""
      }</span>`
    )
    .join("")}</div>`;
}

/* ---------- sections ---------- */

const tabBtn = (id, label) =>
  `<button class="tab ${state.tab === id ? "on" : ""}" data-action="tab" data-tab="${id}">${label}</button>`;

const segBtn = (k, v, on) =>
  `<button class="${on ? "on" : ""}" data-action="ui" data-k="${k}" data-v="${v}">${v}</button>`;

function authHtml() {
  if (state.isAdmin) {
    return `<span class="badge">ADMIN · @${esc(state.me.name)}</span><button class="btn ghost" data-action="logout">Log out</button>`;
  }
  if (state.me) {
    return `<span class="muted">@${esc(state.me.name)} · read-only</span><button class="btn ghost" data-action="logout">Log out</button>`;
  }
  return `<button class="btn" data-action="login">Sign in with Hugging Face</button>`;
}

function saveHtml() {
  if (!state.saveStatus) return "";
  return (
    `<span class="save ${state.saveFailed ? "err" : ""}">${esc(state.saveStatus)}</span>` +
    (state.saveFailed ? `<button class="btn" data-action="save">Retry</button>` : "")
  );
}

function runCard(r) {
  const running = r.status === "running" && !r.stoppedAt;
  const start = Date.parse(r.startedAt);
  const stop = r.stoppedAt ? Date.parse(r.stoppedAt) : "";
  const stat = (label, value) =>
    `<div class="stat"><span class="lbl">${label}</span><span class="mono">${value}</span></div>`;
  return `
  <div class="card">
    <div class="run-head">
      <span class="dot" style="background:${esc(r.color)}"></span>
      <b>${esc(r.name)}</b>
      <span class="status ${running ? "live" : ""}">${running ? "running" : "stopped"}</span>
      <span class="mono">step ${fmtInt(r.step)}</span>
      <span class="mono elapsed" data-start="${start}" data-stop="${stop}">${fmtDuration((stop || Date.now()) - start)}</span>
    </div>
    <div class="stats">
      ${stat("avg@n", fmtNum(metricLast("dynsam", "avg@n", r.id)))}
      ${stat("cost so far", fmtMoney(r.costSoFar))}
      ${stat("tokens · step", fmtBig(r.tokensAtStep))}
      ${stat("tokens · total", fmtBig(r.tokensTotal))}
      ${stat("samples trained", fmtBig(r.samplesTrained))}
      ${stat("train batch × rollouts", `${fmtInt(r.trainBatch)} × ${r.rollouts ?? "—"}`)}
    </div>
  </div>`;
}

function noticesHtml() {
  const items = [...state.data.notices].sort((a, b) => Date.parse(b.time) - Date.parse(a.time));
  const form = state.isAdmin
    ? `<div class="notice-form" data-admin>
         <textarea id="notice-text" rows="2" placeholder="Write a notice for everyone…"></textarea>
         <div class="row"><button class="btn" data-action="post-notice">Post notice</button>${saveHtml()}</div>
       </div>`
    : "";
  const list = items.length
    ? items
        .map(
          (n) => `
        <div class="notice">
          <span class="mono muted">${fmtUtc(n.time)}</span>
          <span class="ntext">${esc(n.text)}</span>
          ${state.isAdmin ? `<button class="x" data-action="del-notice" data-id="${esc(n.id)}" title="Delete">×</button>` : ""}
        </div>`
        )
        .join("")
    : `<div class="muted">No notices.</div>`;
  return `
  <section class="card">
    <div class="mhead"><b>notices</b><span class="muted">UTC</span></div>
    ${form}
    ${list}
  </section>`;
}

function readCostForm() {
  const raw = $("#cost-correct").value.trim();
  const correct = raw === "" ? Math.round(costNow()) : Number(raw);
  const inc = Number($("#cost-inc").value);
  const every = Number($("#cost-every").value);
  const unit = $("#cost-unit").value;
  const ok = isFinite(correct) && isFinite(inc) && inc >= 0 && isFinite(every) && every > 0;
  return { ok, correct, inc, every, unit };
}

function updateCostPreview() {
  const el = $("#cost-preview");
  if (!el) return;
  const f = readCostForm();
  el.textContent = f.ok
    ? `Preview: shows ${fmtMoney(f.correct)} now, then ${rateText({ increment: f.inc, every: f.every, unit: f.unit })}`
    : "Enter valid numbers.";
}

function adminCostHtml() {
  const c = state.data.cost;
  return `
  <section class="card admin" data-admin>
    <div class="mhead"><b>admin · cost</b><span class="muted">saved to the dataset repo</span></div>
    <div class="form-grid">
      <label>Correct current value ($)<input id="cost-correct" type="number" step="any" placeholder="${Math.round(costNow())}"></label>
      <label>Increase ($)<input id="cost-inc" type="number" min="0" step="any" value="${c.increment}"></label>
      <label>every<input id="cost-every" type="number" min="0.0001" step="any" value="${c.every}"></label>
      <label>unit<select id="cost-unit">${UNITS.map((u) => `<option value="${u}" ${u === c.unit ? "selected" : ""}>${u}</option>`).join("")}</select></label>
    </div>
    <div class="muted" id="cost-preview"></div>
    <div class="row"><button class="btn" data-action="save-cost">Save cost</button>${saveHtml()}</div>
  </section>`;
}

function benchHtml() {
  const bs = state.data.benchmarks;
  if (!bs.length) return "";
  const cards = bs
    .map((b) => {
      const series = Object.keys(b.series).map((k) => ({ name: runName(k), color: runColor(k), values: b.series[k] }));
      return `
      <div class="card">
        <div class="mhead"><b>${esc(b.name)}</b><span class="muted">${esc(b.subtitle || "")}</span></div>
        ${legendHtml(series)}
        ${chartSvg(series)}
      </div>`;
    })
    .join("");
  return `<h3 class="sec">benchmarks</h3><section class="grid">${cards}</section>`;
}

function batchHtml() {
  const bc = state.data.batchComposition || {};
  const cats = bc.categories || {};
  const keys = Object.keys(cats);
  if (!keys.length) return "";
  const legend = keys
    .map((c) => `<span><i style="background:${CAT_COLORS[c] || "#888"}"></i>${esc(c)}</span>`)
    .join("");
  return `
  <h3 class="sec">batch composition</h3>
  <section class="card">
    <div class="mhead"><span class="muted">what each step's samples are made of · by data source</span></div>
    <div class="toolbar">
      <div class="seg">${segBtn("compMode", "count", state.ui.compMode === "count")}${segBtn("compMode", "share", state.ui.compMode === "share")}</div>
    </div>
    <div class="legend">${legend}</div>
    ${stackedSvg(cats)}
  </section>`;
}

function sourcesHtml() {
  const src = state.data.sources;
  if (!src.length) return "";
  const latest = Math.max(...src.map((s) => s.step));
  const rows = src
    .filter((s) => s.step === latest)
    .sort((a, b) => b.accepted - a.accepted)
    .map((r) => {
      const pct = r.target ? Math.min(100, (r.accepted / r.target) * 100) : 0;
      return `<tr>
        <td>${esc(runName(r.run))}</td>
        <td>${esc(r.name)}</td>
        <td><span style="color:${CAT_COLORS[r.category] || "#888"}">● ${esc(r.category)}</span></td>
        <td class="num">${fmtInt(r.accepted)} / ${fmtInt(r.target)}<div class="bar"><i style="width:${pct}%"></i></div></td>
        <td class="num">${fmtInt(r.remaining)}</td>
        <td class="num">${r.judged == null ? "—" : fmtInt(r.judged)}</td>
        <td class="num">${fmtInt(r.inFlight)}</td>
      </tr>`;
    })
    .join("");
  return `
  <h3 class="sec">sources</h3>
  <section class="card">
    <div class="mhead"><b>latest step · ${latest}</b></div>
    <div class="table-wrap"><table>
      <thead><tr><th>run</th><th>source</th><th>category</th><th class="num">accepted / target</th><th class="num">remaining</th><th class="num">judged</th><th class="num">in flight</th></tr></thead>
      <tbody>${rows}</tbody>
    </table></div>
  </section>`;
}

function feedHtml() {
  const f = state.data.feed;
  const items = f
    .map((x) => `<div><span class="muted">${esc(fmtTime(x.time))}</span> ${esc(x.message)}</div>`)
    .join("");
  return `
  <h3 class="sec">feed</h3>
  <section class="card">
    <div class="mhead"><b>feed</b><span class="muted">UTC</span></div>
    <div class="feed">${items || `<div class="muted">No events.</div>`}</div>
  </section>`;
}

function overviewHtml() {
  return `
    ${state.isAdmin ? adminCostHtml() : ""}
    ${noticesHtml()}
    <section class="runs">${state.data.runs.map(runCard).join("")}</section>
    ${benchHtml()}
    ${batchHtml()}
    ${sourcesHtml()}
    ${feedHtml()}`;
}

function metricCard(m) {
  const series = Object.keys(m.series).map((k) => ({ name: runName(k), color: runColor(k), values: m.series[k] }));
  return `
  <div class="card">
    <div class="mhead"><span class="muted">${esc(m.group)}/</span><b>${esc(m.name)}</b></div>
    ${legendHtml(series, true)}
    ${chartSvg(series)}
  </div>`;
}

function metricGridHtml() {
  const ms = state.data.metrics;
  return ms.length ? ms.map(metricCard).join("") : `<div class="muted">No metrics.</div>`;
}

function metricsHtml() {
  const ui = state.ui;
  return `
  <div class="toolbar">
    <div class="seg">${segBtn("xMode", "step", ui.xMode === "step")}${segBtn("xMode", "time", ui.xMode === "time")}</div>
    <div class="seg">${segBtn("yLog", "linear", !ui.yLog)}${segBtn("yLog", "log", ui.yLog)}</div>
    <label class="smooth">smoothing
      <input id="smooth" type="range" min="0" max="10" step="1" value="${ui.smooth}">
      <span class="mono" id="smooth-val">${ui.smooth > 1 ? ui.smooth + " pts" : "off"}</span>
    </label>
  </div>
  <div class="grid" id="metric-grid">${metricGridHtml()}</div>`;
}

function renderMd(src) {
  return esc(src || "")
    .split(/\n\s*\n/)
    .map((block) => {
      if (/^#\s/.test(block)) return `<h2>${block.replace(/^#\s/, "")}</h2>`;
      if (/^- /m.test(block)) {
        const items = block.split("\n").map((l) => `<li>${l.replace(/^- /, "")}</li>`).join("");
        return `<ul>${items}</ul>`;
      }
      return `<p>${block.replace(/\n/g, "<br>")}</p>`;
    })
    .join("");
}

function aboutHtml() {
  const admin = state.isAdmin
    ? `<section class="card" data-admin>
         <div class="mhead"><b>edit about</b><span class="muted"># heading · - bullets · blank line = new paragraph</span></div>
         <textarea id="about-text" rows="12">${esc(state.data.about)}</textarea>
         <div class="row"><button class="btn" data-action="save-about">Save</button>${saveHtml()}</div>
       </section>`
    : "";
  return `<section class="card prose">${renderMd(state.data.about)}</section>${admin}`;
}

function jsonHtml() {
  const text = state.jsonDraft ?? JSON.stringify(state.data, null, 2);
  return `
  <section class="card admin" data-admin>
    <div class="mhead"><b>Edit data (JSON)</b><span class="muted">validated before saving</span></div>
    <textarea id="json-edit" class="json" rows="28" spellcheck="false">${esc(text)}</textarea>
    <div class="row">
      <span id="json-status" class="${state.jsonError ? "err" : "muted"}">${state.jsonError ? "⚠ " + esc(state.jsonError) : "valid JSON"}</span>
      ${state.dirty ? `<span class="warn">unsaved changes</span>` : ""}
      <button class="btn ghost" data-action="json-discard">Discard</button>
      <button class="btn" data-action="json-save">Save</button>
      ${saveHtml()}
    </div>
  </section>`;
}

function mainHtml() {
  if (state.tab === "metrics") return metricsHtml();
  if (state.tab === "about") return aboutHtml();
  if (state.tab === "json" && state.isAdmin) return jsonHtml();
  return overviewHtml();
}

function footerHtml() {
  const f = state.data.footer || {};
  const synced = state.lastSync ? ` · synced ${state.lastSync.toLocaleTimeString("en-GB", { hour12: false })}` : "";
  return `<footer>@${esc(CONFIG.OWNER_HF_USERNAME)} · streaming since ${fmtUtc(f.streamingSince)} · ${esc(f.tagline || "")}${synced}</footer>`;
}

/* ---------- render & ticks ---------- */

function render() {
  const d = state.data;
  const banner = state.error || state.authError;
  $("#app").innerHTML = `
    <header class="topbar">
      <div class="brand">RL training</div>
      <nav class="tabs">
        ${tabBtn("overview", "overview")}${tabBtn("metrics", "metrics")}${tabBtn("about", "about")}
        ${state.isAdmin ? tabBtn("json", "edit data (JSON)") : ""}
      </nav>
      <div class="cost">
        <span class="lbl">total cost</span>
        <span class="val" data-cost>${d ? fmtMoney(costNow()) : "—"}</span>
        <span class="rate">${d ? rateText(d.cost) : ""}</span>
      </div>
      <div class="clocks">${CONFIG.DISPLAY_TIMEZONES
        .map((z) => `<div><span class="lbl">${esc(z.label)}</span><span class="mono" data-clock="${z.tz}"></span></div>`)
        .join("")}</div>
      <div class="auth">${authHtml()}<button class="btn ghost" data-action="theme" title="Toggle theme">◐</button></div>
    </header>
    ${banner && d ? `<div class="banner">Sync problem (${esc(banner)}), showing last good data.</div>` : ""}
    ${banner && !d ? `<div class="banner err">Could not load data: ${esc(banner)}</div>` : ""}
    <main>${d ? mainHtml() : `<div class="muted pad">Loading…</div>`}</main>
    ${d ? footerHtml() : ""}
  `;
  tickTime();
  tickCost();
  updateCostPreview();
}

function tickCost() {
  if (!state.data) return;
  const txt = fmtMoney(costNow());
  document.querySelectorAll("[data-cost]").forEach((el) => (el.textContent = txt));
}

function tickTime() {
  const now = new Date();
  document.querySelectorAll("[data-clock]").forEach((el) => {
    el.textContent = new Intl.DateTimeFormat("en-GB", {
      timeZone: el.dataset.clock,
      hour: "2-digit",
      minute: "2-digit",
      second: "2-digit",
      hourCycle: "h23",
    }).format(now);
  });
  document.querySelectorAll(".elapsed").forEach((el) => {
    const start = Number(el.dataset.start);
    const end = el.dataset.stop ? Number(el.dataset.stop) : Date.now();
    el.textContent = fmtDuration(end - start);
  });
}

/* ---------- data flow ---------- */

function normalize(d) {
  const cost = {
    base: 0,
    baseTime: new Date().toISOString(),
    increment: 0,
    every: 1,
    unit: "hour",
    ...(d.cost || {}),
  };
  return {
    notices: [],
    runs: [],
    metrics: [],
    benchmarks: [],
    sources: [],
    feed: [],
    about: "",
    footer: {},
    ...d,
    cost,
    batchComposition: d.batchComposition || { categories: {} },
  };
}

async function sync(force = false) {
  if (state.dirty && !force) return;
  try {
    state.data = normalize(await hf.readData());
    state.error = null;
    state.lastSync = new Date();
  } catch (e) {
    state.error = e.message;
  }
  render();
}

async function save() {
  if (!state.token) return;
  state.saveStatus = "Saving...";
  state.saveFailed = false;
  render();
  try {
    await hf.writeData(state.token, state.data);
    state.dirty = false;
    state.jsonDraft = null;
    state.jsonError = "";
    state.saveStatus = "Saved";
    await sync(true);
  } catch (e) {
    state.saveStatus = "Failed: " + e.message;
    state.saveFailed = true;
    render();
  }
}

async function refreshIdentity() {
  state.me = await hf.whoami(state.token).catch(() => null);
  if (!state.me) {
    hf.logout();
    state.token = null;
  }
  state.isAdmin = !!state.me && state.me.name?.toLowerCase() === CONFIG.OWNER_HF_USERNAME.toLowerCase();
}

async function init() {
  try {
    state.token = (await hf.handleRedirect()) || sessionStorage.getItem("hf_token");
  } catch (e) {
    state.authError = e.message;
  }
  if (state.token) await refreshIdentity();
  await sync(true);
  setInterval(() => sync(false), CONFIG.REFRESH_MS);
  setInterval(tickCost, 100);
  setInterval(tickTime, 1000);
}

/* ---------- events ---------- */

document.addEventListener("click", async (e) => {
  const el = e.target.closest("[data-action]");
  if (!el) return;
  switch (el.dataset.action) {
    case "tab":
      state.tab = el.dataset.tab;
      render();
      break;
    case "login":
      hf.login();
      break;
    case "logout":
      hf.logout();
      state.token = null;
      state.me = null;
      state.isAdmin = false;
      state.dirty = false;
      render();
      break;
    case "theme":
      document.body.classList.toggle("light");
      break;
    case "ui": {
      const k = el.dataset.k;
      const v = el.dataset.v;
      state.ui[k] = k === "yLog" ? v === "log" : v;
      render();
      break;
    }
    case "post-notice": {
      const text = $("#notice-text").value.trim();
      if (!text) break;
      state.data.notices.push({ id: "n" + Date.now(), time: new Date().toISOString(), text });
      save();
      break;
    }
    case "del-notice":
      if (confirm("Delete this notice?")) {
        state.data.notices = state.data.notices.filter((n) => n.id !== el.dataset.id);
        save();
      }
      break;
    case "save-cost": {
      const f = readCostForm();
      if (!f.ok) {
        state.saveStatus = "Invalid cost values";
        state.saveFailed = true;
        render();
        break;
      }
      state.data.cost = {
        base: f.correct,
        baseTime: new Date().toISOString(),
        increment: f.inc,
        every: f.every,
        unit: f.unit,
      };
      save();
      break;
    }
    case "save-about":
      state.data.about = $("#about-text").value;
      save();
      break;
    case "json-save": {
      try {
        const parsed = JSON.parse(state.jsonDraft ?? JSON.stringify(state.data));
        state.data = normalize(parsed);
        state.jsonError = "";
        save();
      } catch (err) {
        state.jsonError = err.message;
        render();
      }
      break;
    }
    case "json-discard":
      state.jsonDraft = null;
      state.jsonError = "";
      state.dirty = false;
      sync(true);
      break;
    case "save":
      save();
      break;
  }
});

function handleField(e) {
  const t = e.target;
  if (t.closest?.("[data-admin]")) state.dirty = true;

  if (t.id === "json-edit") {
    state.jsonDraft = t.value;
    try {
      JSON.parse(t.value);
      state.jsonError = "";
    } catch (err) {
      state.jsonError = err.message;
    }
    const s = $("#json-status");
    if (s) {
      s.textContent = state.jsonError ? "⚠ " + state.jsonError : "valid JSON";
      s.className = state.jsonError ? "err" : "muted";
    }
  }

  if (t.id?.startsWith("cost-")) updateCostPreview();

  if (t.id === "smooth") {
    state.ui.smooth = Number(t.value);
    $("#smooth-val").textContent = state.ui.smooth > 1 ? state.ui.smooth + " pts" : "off";
    $("#metric-grid").innerHTML = metricGridHtml();
  }
}
document.addEventListener("input", handleField);
document.addEventListener("change", handleField);

document.addEventListener("pointermove", (e) => {
  const tip = $("#tip");
  const svg = e.target.closest?.("svg[data-chart]");
  const c = svg && chartStore[svg.dataset.chart];
  if (!c) {
    tip.hidden = true;
    return;
  }
  const r = svg.getBoundingClientRect();
  const x = ((e.clientX - r.left) / r.width) * c.W;
  const frac = (x - c.pl) / (c.W - c.pl - c.pr);
  const i = Math.max(0, Math.min(c.n - 1, Math.round(frac * (c.n - 1))));
  tip.innerHTML =
    `<div class="muted">step ${esc(c.labels[i])}</div>` +
    c.ser
      .map((s) => `<div><i style="background:${s.color}"></i>${esc(s.name)}: <b>${fmtNum(s.values[i])}</b></div>`)
      .join("");
  tip.hidden = false;
  tip.style.left = e.clientX + 14 + "px";
  tip.style.top = e.clientY + 14 + "px";
});

init();