const ACCENT = "#5eead4";
const BASE = "#6b7280";
const css = (v) => getComputedStyle(document.documentElement).getPropertyValue(v).trim();

let DATA = null;
let scoreChart = null;
let lenChart = null;
let loading = false;

const $ = (id) => document.getElementById(id);

function shortKey(k) {
  if (!k || k.length <= 14) return { head: k || "pending", tail: "" };
  return { head: k.slice(0, 8), tail: "…" + k.slice(-6) };
}

async function load() {
  await refreshData(true);
  window.setInterval(() => refreshData(false), 15000);
}

async function refreshData(initial) {
  if (loading) return;
  loading = true;
  const previousView = $("validator-select")?.value;
  try {
    const res = await fetch("./data.json", { cache: "no-store" });
    if (!res.ok) throw new Error("HTTP " + res.status);
    DATA = await res.json();
  } catch (err) {
    console.error("Failed to load data.json", err);
    if (initial || !DATA) {
      $("board-empty").hidden = false;
      $("board-empty").textContent = "Data is not ready yet";
    }
    loading = false;
    return;
  }
  hydrateUpdated();
  buildViews(previousView);
  renderActiveView();
  loading = false;
}

function hydrateUpdated() {
  const ts = DATA.generated_at;
  const date = ts ? new Date(ts) : null;
  const label = date && !Number.isNaN(date.getTime()) ? formatTimestamp(date) : "unknown";
  $("updated").textContent = "latest " + label;
  $("footer-meta").textContent = DATA.sample ? "sample data" : "live data";
}

function formatTimestamp(date) {
  const day = date.toLocaleDateString(undefined, { year: "2-digit", month: "numeric", day: "numeric" });
  const time = date.toLocaleTimeString(undefined, { hour: "numeric", minute: "2-digit" });
  return `${day} ${time}`;
}

function buildViews(preferredView) {
  const select = $("validator-select");
  select.innerHTML = "";
  const views = [];

  for (const v of DATA.validators || []) {
    const sk = shortKey(v.hotkey);
    views.push({ id: v.hotkey, label: "Validator " + sk.head + sk.tail });
  }
  for (const view of views) {
    const opt = document.createElement("option");
    opt.value = view.id;
    opt.textContent = view.label;
    select.appendChild(opt);
  }
  if (preferredView && views.some((view) => view.id === preferredView)) {
    select.value = preferredView;
  }
  select.onchange = renderActiveView;

  $("stat-validators").textContent = (DATA.validators || []).length || "0";
}

const FULL_EVALUATION_ENTRANT_STATES = new Set(["evaluating", "finished", "failed"]);

function roundParticipation(progresses) {
  const miners = new Map();
  let hasCurrentRound = false;

  for (const progress of progresses) {
    for (const [stageName, stage] of Object.entries(progress?.stages || {})) {
      if (stageName !== "qualification" && stageName !== "full_evaluation") continue;
      const entries = Object.entries(stage?.miners || {});
      if (entries.length) hasCurrentRound = true;
      for (const [hotkey, status] of entries) {
        const participation = miners.get(hotkey) || {
          qualification: false,
          fullEvaluation: false,
          qualificationStatus: null,
          fullEvaluationStatus: null,
        };
        if (stageName === "qualification") {
          participation.qualification = true;
          participation.qualificationStatus = status;
        }
        if (stageName === "full_evaluation" && FULL_EVALUATION_ENTRANT_STATES.has(status)) {
          participation.fullEvaluation = true;
        }
        if (stageName === "full_evaluation") participation.fullEvaluationStatus = status;
        miners.set(hotkey, participation);
      }
    }
  }
  return { miners, hasCurrentRound };
}

function numericScore(value) {
  return typeof value === "number" && Number.isFinite(value) ? value : null;
}

function currentRoundRows(progress) {
  const round = roundParticipation(progress ? [progress] : []);
  const qualificationScores = progress?.stages?.qualification?.scores || {};
  const fullEvaluationScores = progress?.stages?.full_evaluation?.scores || {};
  const rows = [...round.miners].map(([hotkey, participation]) => ({
    hotkey,
    participation,
    qualificationScore: numericScore(qualificationScores[hotkey]),
    fullEvaluationScore: numericScore(fullEvaluationScores[hotkey]),
  }));
  rows.sort((a, b) => {
    if (a.fullEvaluationScore != null || b.fullEvaluationScore != null) {
      if (a.fullEvaluationScore == null) return 1;
      if (b.fullEvaluationScore == null) return -1;
      return b.fullEvaluationScore - a.fullEvaluationScore;
    }
    if (a.qualificationScore == null) {
      return b.qualificationScore == null ? a.hotkey.localeCompare(b.hotkey) : 1;
    }
    if (b.qualificationScore == null) return -1;
    return b.qualificationScore - a.qualificationScore;
  });
  return { rows, hasCurrentRound: round.hasCurrentRound, hotkeys: new Set(round.miners.keys()) };
}

function scoreFromHistory(history, hotkey, epoch) {
  const epochs = history?.epochs || [];
  const index = epochs.indexOf(epoch);
  if (index < 0) return null;
  return numericScore(history?.miners?.[hotkey]?.score?.[index]);
}

function stageScoresFromHistory(history, epoch) {
  const snapshot = (history?.stage_scores || []).find((row) => row.epoch === epoch);
  return {
    qualification: snapshot?.qualification || {},
    fullEvaluation: snapshot?.full_evaluation || {},
  };
}

function previousRoundRows(rankings, history, progress, currentHotkeys) {
  const epochs = history?.epochs || [];
  const currentEpoch = numericScore(progress?.epoch);
  const previousEpoch = currentEpoch == null
    ? (epochs.length ? epochs[epochs.length - 1] : null)
    : [...epochs].reverse().find((epoch) => epoch < currentEpoch) ?? null;
  const latestCompletedEpoch = epochs.length ? epochs[epochs.length - 1] : null;
  const finalScores = new Map();

  if (previousEpoch != null) {
    for (const hotkey of Object.keys(history?.miners || {})) {
      const score = scoreFromHistory(history, hotkey, previousEpoch);
      if (score != null) finalScores.set(hotkey, score);
    }
  }
  if (previousEpoch == null && latestCompletedEpoch == null) {
    for (const row of rankings) {
      const score = numericScore(row.score);
      if (score != null && !finalScores.has(row.hotkey)) finalScores.set(row.hotkey, score);
    }
  }

  const stageScores = stageScoresFromHistory(history, previousEpoch);
  const hotkeys = new Set([
    ...finalScores.keys(),
    ...Object.keys(stageScores.qualification),
    ...Object.keys(stageScores.fullEvaluation),
  ]);
  const rows = [...hotkeys].map((hotkey) => ({
    hotkey,
    finalScore: finalScores.get(hotkey) ?? null,
    qualificationScore: numericScore(stageScores.qualification[hotkey]),
    fullEvaluationScore: numericScore(stageScores.fullEvaluation[hotkey]),
    isCurrent: currentHotkeys.has(hotkey),
  }));
  rows.sort((a, b) => {
    if (a.finalScore == null) return b.finalScore == null ? a.hotkey.localeCompare(b.hotkey) : 1;
    if (b.finalScore == null) return -1;
    return b.finalScore - a.finalScore;
  });
  rows.forEach((row, index) => { row.previousRank = row.finalScore == null ? null : index + 1; });
  return { rows, epoch: previousEpoch };
}

function olderMinerRows(history, currentHotkeys, previousRows, previousEpoch) {
  if (previousEpoch == null) return [];
  const epochs = history?.epochs || [];
  const excluded = new Set([...currentHotkeys, ...previousRows.map((row) => row.hotkey)]);
  const rows = [];
  for (const [hotkey, series] of Object.entries(history?.miners || {})) {
    if (excluded.has(hotkey)) continue;
    let index = epochs.length - 1;
    while (index >= 0 && (epochs[index] >= previousEpoch || numericScore(series?.score?.[index]) == null)) {
      index -= 1;
    }
    if (index < 0) continue;
    const epoch = epochs[index];
    const stageScores = stageScoresFromHistory(history, epoch);
    rows.push({
      hotkey,
      lastScoredEpoch: epoch,
      finalScore: numericScore(series.score[index]),
      qualificationScore: numericScore(stageScores.qualification[hotkey]),
      fullEvaluationScore: numericScore(stageScores.fullEvaluation[hotkey]),
    });
  }
  rows.sort((a, b) => (
    b.lastScoredEpoch - a.lastScoredEpoch
    || (b.finalScore ?? -Infinity) - (a.finalScore ?? -Infinity)
  ));
  return rows;
}

function activeView() {
  const id = $("validator-select").value;
  const v = (DATA.validators || []).find((x) => x.hotkey === id);
  const current = currentRoundRows(v?.progress || null);
  const previous = previousRoundRows(
    v?.rankings || [],
    v?.history || null,
    v?.progress || null,
    current.hotkeys,
  );
  const older = olderMinerRows(v?.history || null, current.hotkeys, previous.rows, previous.epoch);
  return {
    rankings: current.rows,
    previousRankings: previous.rows,
    previousEpoch: previous.epoch,
    olderRankings: older,
    hasCurrentRound: current.hasCurrentRound,
    history: v?.history || null,
    progress: v?.progress || null,
    validator: v || null,
  };
}

function renderActiveView() {
  const view = activeView();
  renderBoard(view);
  renderStats(view);
  renderProgress(view);
  renderTrends(view);
}

function renderStats(view) {
  const top = view.rankings.find((row) => row.fullEvaluationScore != null);
  $("stat-miners").textContent = view.rankings.length;
  $("stat-top").textContent = top ? top.fullEvaluationScore.toFixed(3) : "-";
  const ep = view.history?.epochs;
  $("stat-epoch").textContent = view.progress?.epoch ?? (ep && ep.length ? ep[ep.length - 1] : "0");
}

const TERMINAL_MINER_STATES = new Set(["finished", "failed", "rejected", "skipped", "not_selected"]);

function statusLabel(status) {
  return String(status || "waiting").replaceAll("_", " ");
}

function statusClass(status) {
  const safe = String(status || "waiting").toLowerCase().replaceAll("_", "-").replace(/[^a-z-]/g, "");
  return "status-" + safe;
}

function compactStatusLabel(status) {
  switch (status) {
    case "completed":
    case "finished":
      return "done";
    case "evaluating":
    case "running":
      return "live";
    case "not_selected":
      return "out";
    default:
      return statusLabel(status || "waiting");
  }
}

function appendHotkey(parent, value) {
  const sk = shortKey(value);
  const hotkey = document.createElement("span");
  hotkey.className = "hotkey";
  const head = document.createElement("span");
  head.className = "head";
  head.textContent = sk.head;
  const tail = document.createElement("span");
  tail.className = "tail";
  tail.textContent = sk.tail;
  hotkey.append(head, tail);
  parent.appendChild(hotkey);
}

function progressTimestamp(progress) {
  const date = progress?.updated_at ? new Date(progress.updated_at) : null;
  return date && !Number.isNaN(date.getTime()) ? date : null;
}

function displayProgressStatus(progress) {
  return progress?.status || "waiting";
}

function stageStats(stage) {
  const entries = Object.entries(stage?.miners || {});
  const resolved = entries.filter(([, status]) => TERMINAL_MINER_STATES.has(status)).length;
  const finished = entries.filter(([, status]) => status === "finished").length;
  const evaluating = entries.filter(([, status]) => status === "evaluating").length;
  return { total: entries.length, resolved, finished, evaluating };
}

function stageProgressPercent(stats) {
  return stats.total ? Math.round((stats.resolved / stats.total) * 100) : 0;
}

function baselineStatus(stage) {
  return stage?.baseline || "waiting";
}

function stageScore(stage, hotkey) {
  const score = stage?.scores?.[hotkey];
  return typeof score === "number" && Number.isFinite(score) ? score : null;
}

function stageTopScore(stage) {
  const scores = Object.values(stage?.scores || {}).filter(
    (value) => typeof value === "number" && Number.isFinite(value),
  );
  return scores.length ? Math.max(...scores) : null;
}

function formatScore(value) {
  return value == null ? "-" : value.toFixed(3);
}

function formatDuration(seconds) {
  if (typeof seconds !== "number" || !Number.isFinite(seconds) || seconds < 0) return null;
  if (seconds < 60) return `${seconds.toFixed(1)}s`;
  const minutes = Math.floor(seconds / 60);
  const rest = Math.round(seconds % 60);
  return `${minutes}m ${String(rest).padStart(2, "0")}s`;
}

function baselineDurationLabel(stage) {
  return formatDuration(stage?.baseline_seconds);
}

function stageDurationLabel(stage) {
  return formatDuration(stage?.duration_seconds);
}

function stageIsEvaluating(stage, stats = stageStats(stage)) {
  return stage?.status === "evaluating" || baselineStatus(stage) === "evaluating" || stats.evaluating > 0;
}

function renderProgress(view) {
  const content = $("progress-content");
  content.innerHTML = "";
  if (!view.validator) {
    renderProgressOverview(content);
    return;
  }

  const progress = view.progress;
  const validatorKey = shortKey(view.validator.hotkey);
  $("progress-subtitle").textContent = `Epoch ${progress?.epoch ?? "-"} from validator ${validatorKey.head}${validatorKey.tail}`;
  const overallStatus = displayProgressStatus(progress);
  $("progress-status").textContent = statusLabel(overallStatus);
  $("progress-status").className = `status-pill ${statusClass(overallStatus)}`;
  const updated = progressTimestamp(progress);
  $("progress-updated").textContent = updated ? formatTimestamp(updated) : "syncing";

  if (!progress) {
    const empty = document.createElement("div");
    empty.className = "empty";
    empty.textContent = "Waiting for this validator";
    content.appendChild(empty);
    return;
  }

  const grid = document.createElement("div");
  grid.className = "stage-grid";
  grid.append(
    renderStageCard("Qualification", progress.stages?.qualification),
    renderStageCard("Full evaluation", progress.stages?.full_evaluation),
  );
  content.appendChild(grid);
}

function renderProgressOverview(content) {
  $("progress-subtitle").textContent = "Live stage health across validators";
  $("progress-status").textContent = "all";
  $("progress-status").className = "status-pill";
  const validators = DATA.validators || [];
  const dates = validators.map((validator) => progressTimestamp(validator.progress)).filter(Boolean);
  const latest = dates.length ? new Date(Math.max(...dates.map((date) => date.getTime()))) : null;
  $("progress-updated").textContent = latest ? formatTimestamp(latest) : "syncing";

  if (!validators.length) {
    const empty = document.createElement("div");
    empty.className = "empty";
    empty.textContent = "Waiting for validator progress";
    content.appendChild(empty);
    return;
  }

  const overview = document.createElement("div");
  overview.className = "progress-overview";
  for (const validator of validators) overview.appendChild(renderValidatorProgressRow(validator));
  content.appendChild(overview);
}

function renderValidatorProgressRow(validator) {
  const row = document.createElement("div");
  row.className = "validator-progress-row";
  const name = document.createElement("div");
  name.className = "validator-progress-name";
  appendHotkey(name, validator.hotkey);
  const status = displayProgressStatus(validator.progress);
  const pill = document.createElement("span");
  pill.className = `status-pill ${statusClass(status)}`;
  pill.textContent = statusLabel(status);
  name.appendChild(pill);
  row.append(
    name,
    renderStageSummary("Qualification", validator.progress?.stages?.qualification),
    renderStageSummary("Full evaluation", validator.progress?.stages?.full_evaluation),
  );
  return row;
}

function renderStageSummary(label, stage) {
  const summary = document.createElement("div");
  const stats = stageStats(stage);
  summary.className = stageIsEvaluating(stage, stats) ? "stage-summary is-evaluating" : "stage-summary";
  const baseDuration = baselineDurationLabel(stage);
  summary.title = stage
    ? `${label} ${statusLabel(stage.status)} with base ${statusLabel(baselineStatus(stage))}` +
      (baseDuration ? ` (${baseDuration})` : "") +
      ` and ${stats.resolved}/${stats.total} miners complete`
    : `${label} waiting for data`;

  const head = document.createElement("div");
  head.className = "stage-summary-head";
  const title = document.createElement("strong");
  title.textContent = label;
  const state = document.createElement("span");
  state.className = `stage-state ${statusClass(stage?.status)}`;
  state.textContent = compactStatusLabel(stage?.status);
  head.append(title, state);

  const meter = document.createElement("div");
  meter.className = "stage-mini-bar";
  const fill = document.createElement("i");
  fill.style.width = `${stageProgressPercent(stats)}%`;
  meter.appendChild(fill);

  const foot = document.createElement("div");
  foot.className = "stage-summary-foot";
  const done = document.createElement("span");
  done.className = "stage-mini-count";
  done.textContent = stage ? `${stats.resolved}/${stats.total}` : "0/0";
  done.setAttribute("aria-label", "miners complete");
  const baseline = document.createElement("span");
  const baseStatus = baselineStatus(stage);
  baseline.className = `stage-mini-base ${statusClass(baseStatus)}`;
  baseline.textContent = `base ${compactStatusLabel(baseStatus)}` + (baseDuration ? ` · ${baseDuration}` : "");
  baseline.title = `Base model ${statusLabel(baseStatus)}` + (baseDuration ? ` in ${baseDuration}` : "");
  foot.append(done, baseline);
  if (stats.evaluating) {
    const active = document.createElement("span");
    active.className = "stage-mini-active";
    active.textContent = `${stats.evaluating} active`;
    foot.appendChild(active);
  }

  summary.append(head, meter, foot);
  return summary;
}

function renderStageCard(label, stage) {
  const card = document.createElement("section");
  const stats = stageStats(stage);
  const isEvaluating = stageIsEvaluating(stage, stats);
  card.className = isEvaluating ? "stage-card is-evaluating" : "stage-card";
  const head = document.createElement("div");
  head.className = "stage-head";
  const titleRow = document.createElement("div");
  titleRow.className = "stage-title-row";
  const title = document.createElement("span");
  title.className = "stage-title";
  title.textContent = label;
  const pill = document.createElement("span");
  pill.className = `status-pill ${statusClass(stage?.status)}`;
  pill.textContent = statusLabel(stage?.status);
  const stageDuration = stageDurationLabel(stage);
  if (stageDuration) pill.title = `took ${stageDuration}`;
  titleRow.append(title, pill);

  const count = document.createElement("div");
  const bar = document.createElement("div");
  count.className = "stage-metrics";
  const baseDuration = baselineDurationLabel(stage);
  count.append(
    renderStageMetric("done", `${stats.resolved}/${stats.total}`),
    renderStageMetric("active", String(stats.evaluating)),
    renderStageMetric(
      "base",
      compactStatusLabel(baselineStatus(stage)) + (baseDuration ? ` · ${baseDuration}` : ""),
    ),
    renderStageMetric("top", formatScore(stageTopScore(stage))),
  );
  bar.className = isEvaluating ? "stage-bar is-evaluating" : "stage-bar";
  const fill = document.createElement("i");
  fill.style.width = `${stageProgressPercent(stats)}%`;
  bar.appendChild(fill);
  head.append(titleRow, count, bar);
  card.appendChild(head);

  const list = document.createElement("div");
  list.className = "miner-state-list";
  if (stage) {
    const baselineRow = document.createElement("div");
    baselineRow.className = "miner-state-row baseline-state-row";
    const label = document.createElement("span");
    label.className = "baseline-label";
    label.textContent = "Base model";
    const state = document.createElement("span");
    const baseStatus = baselineStatus(stage);
    const baseDuration = baselineDurationLabel(stage);
    state.className = `miner-state ${statusClass(baseStatus)}`;
    state.textContent = statusLabel(baseStatus) + (baseDuration ? ` · ${baseDuration}` : "");
    baselineRow.append(label, state);
    list.appendChild(baselineRow);
  }
  const miners = Object.entries(stage?.miners || {});
  if (!miners.length) {
    const empty = document.createElement("div");
    empty.className = "empty";
    empty.textContent = "No miners yet";
    list.appendChild(empty);
  } else {
    for (const [hotkey, minerStatus] of miners) {
      const row = document.createElement("div");
      row.className = "miner-state-row";
      appendHotkey(row, hotkey);
      const score = stageScore(stage, hotkey);
      const state = document.createElement("span");
      state.className = `miner-state ${statusClass(minerStatus)}`;
      state.textContent = statusLabel(minerStatus) + (score != null ? ` · ${formatScore(score)}` : "");
      row.appendChild(state);
      list.appendChild(row);
    }
  }
  card.appendChild(list);
  return card;
}

function renderStageMetric(label, value) {
  const metric = document.createElement("span");
  metric.className = `stage-metric stage-metric-${label}`;
  const key = document.createElement("span");
  key.textContent = label;
  const val = document.createElement("strong");
  val.textContent = value;
  metric.append(key, val);
  return metric;
}

function participationLabel(participation) {
  if (!participation) return "Latest ranking";
  if (participation.qualification && participation.fullEvaluation) return "Qualification + full";
  if (participation.fullEvaluation) return "Full evaluation";
  return "Qualification";
}

function renderParticipation(participation) {
  const badge = document.createElement("span");
  badge.className = "entry-badge";
  if (participation?.fullEvaluation) badge.classList.add("entry-full");
  badge.textContent = participationLabel(participation);
  return badge;
}

function stageScoreText(score, status) {
  if (score != null) return score.toFixed(4);
  if (status === "not_selected") return "not selected";
  if (status === "failed" || status === "rejected" || status === "skipped") return statusLabel(status);
  if (status === "evaluating") return "evaluating";
  return "pending";
}

function renderScoreCell(score, status, className) {
  const cell = document.createElement("td");
  cell.className = `score-val ${className}`;
  cell.textContent = stageScoreText(score, status);
  if (score == null) cell.classList.add("score-pending");
  return cell;
}

function renderBoard(view) {
  const rankings = view.rankings;
  const body = $("board-body");
  body.innerHTML = "";
  $("board-empty").hidden = rankings.length > 0;
  $("ranking-subtitle").textContent = view.hasCurrentRound
    ? `Stage scores from epoch ${view.progress?.epoch ?? "-"}`
    : "Waiting for current-round participation";
  let displayedRank = 0;

  rankings.forEach((r) => {
    const tr = document.createElement("tr");
    const hasFullScore = r.fullEvaluationScore != null;
    if (hasFullScore) displayedRank += 1;
    tr.className = hasFullScore ? "rank-" + displayedRank : "rank-pending";
    if (displayedRank === 1 && hasFullScore) tr.classList.add("is-king");
    const sk = shortKey(r.hotkey);

    const rankCell = document.createElement("td");
    rankCell.className = "c-rank";
    const rank = document.createElement("span");
    rank.className = "rank-num";
    rank.textContent = hasFullScore ? String(displayedRank).padStart(2, "0") : "--";
    rankCell.appendChild(rank);

    const hotkeyCell = document.createElement("td");
    const hotkey = document.createElement("span");
    hotkey.className = "hotkey";
    const head = document.createElement("span");
    head.className = "head";
    head.textContent = sk.head;
    const tail = document.createElement("span");
    tail.className = "tail";
    tail.textContent = sk.tail;
    hotkey.append(head, tail);
    hotkeyCell.appendChild(hotkey);
    if (displayedRank === 1 && hasFullScore) {
      const king = document.createElement("span");
      king.className = "king-badge";
      king.textContent = "\u265B King";
      hotkeyCell.appendChild(king);
      tr.setAttribute("aria-label", `King: ${r.hotkey}`);
    }

    const stageCell = document.createElement("td");
    stageCell.className = "c-stage";
    stageCell.appendChild(renderParticipation(r.participation));

    const qualificationCell = renderScoreCell(
      r.qualificationScore,
      r.participation?.qualificationStatus,
      "c-qualification",
    );
    const fullEvaluationCell = renderScoreCell(
      r.fullEvaluationScore,
      r.participation?.fullEvaluationStatus,
      "c-full-evaluation",
    );

    tr.append(rankCell, hotkeyCell, stageCell, qualificationCell, fullEvaluationCell);
    body.appendChild(tr);
  });

  renderPreviousBoard(view.previousRankings, view.previousEpoch);
  renderOlderBoard(view.olderRankings);
}

function renderPreviousBoard(rankings, epoch) {
  const section = $("previous-rankings");
  const body = $("previous-board-body");
  body.innerHTML = "";
  section.hidden = !rankings.length;
  $("previous-count").textContent = epoch == null
    ? `${rankings.length} miners`
    : `${rankings.length} miners · epoch ${epoch}`;

  for (const row of rankings) {
    const tr = document.createElement("tr");
    const rankCell = document.createElement("td");
    rankCell.className = "c-rank";
    rankCell.textContent = row.previousRank == null ? "--" : String(row.previousRank).padStart(2, "0");
    const hotkeyCell = document.createElement("td");
    appendHotkey(hotkeyCell, row.hotkey);
    const statusCell = document.createElement("td");
    statusCell.className = "c-round-status";
    const status = document.createElement("span");
    status.className = row.isCurrent ? "entry-badge" : "status-pill status-stale";
    status.textContent = row.isCurrent ? "also current" : "stale";
    statusCell.appendChild(status);
    const qualificationCell = renderScoreCell(row.qualificationScore, null, "c-qualification");
    const fullEvaluationCell = renderScoreCell(row.fullEvaluationScore, null, "c-full-evaluation");
    const finalScoreCell = renderScoreCell(row.finalScore, null, "c-final-score");
    if (row.qualificationScore == null) qualificationCell.textContent = "-";
    if (row.fullEvaluationScore == null) fullEvaluationCell.textContent = "-";
    if (row.finalScore == null) finalScoreCell.textContent = "-";
    tr.append(
      rankCell,
      hotkeyCell,
      statusCell,
      qualificationCell,
      fullEvaluationCell,
      finalScoreCell,
    );
    body.appendChild(tr);
  }
}

function renderOlderBoard(rankings) {
  const section = $("older-rankings");
  const body = $("older-board-body");
  body.innerHTML = "";
  section.hidden = !rankings.length;
  $("older-count").textContent = `${rankings.length} stale`;

  for (const row of rankings) {
    const tr = document.createElement("tr");
    const epochCell = document.createElement("td");
    epochCell.className = "c-rank";
    epochCell.textContent = String(row.lastScoredEpoch);
    const hotkeyCell = document.createElement("td");
    appendHotkey(hotkeyCell, row.hotkey);
    const qualificationCell = renderScoreCell(row.qualificationScore, null, "c-qualification");
    const fullEvaluationCell = renderScoreCell(row.fullEvaluationScore, null, "c-full-evaluation");
    const finalScoreCell = renderScoreCell(row.finalScore, null, "c-final-score");
    if (row.qualificationScore == null) qualificationCell.textContent = "-";
    if (row.fullEvaluationScore == null) fullEvaluationCell.textContent = "-";
    tr.append(epochCell, hotkeyCell, qualificationCell, fullEvaluationCell, finalScoreCell);
    body.appendChild(tr);
  }
}

function hasPoints(arr) {
  return Array.isArray(arr) && arr.some((x) => x !== null && x !== undefined && !Number.isNaN(x));
}

function topAccuracySeries(history) {
  const epochs = history?.epochs || [];
  const correctnessScore = [];
  const completionLen = [];
  const winners = [];

  for (let index = 0; index < epochs.length; index += 1) {
    let winner = null;
    for (const [hotkey, series] of Object.entries(history?.miners || {})) {
      const accuracy = numericScore(series?.correctness_score?.[index]);
      if (accuracy == null) continue;
      const tokens = numericScore(series?.completion_len?.[index]);
      const betterAccuracy = winner == null || accuracy > winner.accuracy;
      const betterTie = winner != null && accuracy === winner.accuracy && (
        (tokens ?? Infinity) < (winner.tokens ?? Infinity)
        || ((tokens ?? Infinity) === (winner.tokens ?? Infinity) && hotkey < winner.hotkey)
      );
      if (betterAccuracy || betterTie) winner = { hotkey, accuracy, tokens };
    }
    correctnessScore.push(winner?.accuracy ?? null);
    completionLen.push(winner?.tokens ?? null);
    winners.push(winner?.hotkey ?? null);
  }

  return {
    epochs,
    miner: { correctness_score: correctnessScore, completion_len: completionLen },
    original: history?.original || null,
    winners,
  };
}

function renderTrends(view) {
  const s = topAccuracySeries(view.history);
  let latestIndex = s.miner.correctness_score.length - 1;
  while (latestIndex >= 0 && s.miner.correctness_score[latestIndex] == null) latestIndex -= 1;
  const completedEpoch = latestIndex >= 0 ? s.epochs[latestIndex] : null;
  $("trend-miner").textContent = "Best accuracy each epoch";
  $("trend-epoch").textContent = completedEpoch == null ? "waiting" : `through ${completedEpoch}`;

  drawTrend("score", s, "correctness_score");
  drawTrend("len", s, "completion_len");
}

function drawTrend(which, s, field) {
  const canvasId = which === "score" ? "chart-score" : "chart-len";
  const awaitId = which === "score" ? "await-score" : "await-len";
  const minerData = s?.miner?.[field];
  const origData = s?.original?.[field];
  const ok = s && s.epochs.length && (hasPoints(minerData) || hasPoints(origData));

  $(awaitId).hidden = !!ok;
  if (!ok) {
    destroyChart(which);
    return;
  }

  const ctx = $(canvasId).getContext("2d");
  const datasets = [];
  if (hasPoints(minerData)) {
    datasets.push(lineDS("Top miner", minerData, ACCENT, css("--accent-ghost"), false, s.winners));
  }
  if (hasPoints(origData)) datasets.push(lineDS("Base model", origData, BASE, "transparent", true));

  const cfg = {
    type: "line",
    data: { labels: s.epochs, datasets },
    options: chartOptions(which === "len" ? "tokens" : "accuracy", which === "score"),
  };
  destroyChart(which);
  const chart = new Chart(ctx, cfg);
  if (which === "score") scoreChart = chart; else lenChart = chart;
}

function lineDS(label, data, color, fill, dashed = false, winnerHotkeys = null) {
  return {
    label, data,
    borderColor: color,
    backgroundColor: fill,
    borderWidth: 2,
    borderDash: dashed ? [5, 4] : [],
    pointRadius: 0,
    pointHoverRadius: 4,
    tension: 0.25,
    fill: !dashed,
    spanGaps: true,
    winnerHotkeys,
  };
}

function chartOptions(yLabel, signed = false) {
  const grid = css("--line-soft");
  const tick = css("--faint");
  return {
    responsive: true,
    maintainAspectRatio: false,
    interaction: { mode: "index", intersect: false },
    plugins: {
      legend: { labels: { color: css("--muted"), boxWidth: 10, boxHeight: 10, usePointStyle: true, font: { size: 11 } } },
      tooltip: {
        backgroundColor: "#0b0e12", borderColor: css("--line"), borderWidth: 1,
        titleColor: css("--muted"), bodyColor: css("--text"), padding: 10, displayColors: true,
        callbacks: {
          afterLabel(context) {
            const hotkey = context.dataset.winnerHotkeys?.[context.dataIndex];
            if (!hotkey) return "";
            const sk = shortKey(hotkey);
            return `miner ${sk.head}${sk.tail}`;
          },
        },
      },
    },
    scales: {
      x: { title: { display: true, text: "epoch", color: tick, font: { size: 10 } }, grid: { color: grid }, ticks: { color: tick, font: { size: 10 } } },
      y: {
        title: { display: true, text: yLabel, color: tick, font: { size: 10 } },
        min: signed ? -1 : undefined,
        max: signed ? 1 : undefined,
        grid: { color: grid },
        ticks: { color: tick, font: { size: 10 } },
      },
    },
  };
}

function destroyChart(which) {
  if (which === "score" && scoreChart) { scoreChart.destroy(); scoreChart = null; }
  if (which === "len" && lenChart) { lenChart.destroy(); lenChart = null; }
}

window.addEventListener("DOMContentLoaded", load);