/* Brain of Reese — Settings view module (phase 168, task 05): the
 * admin settings panel — "edit anything in .env and save it to the
 * database. The database value should override the env var. The
 * change should take effect on clicking 'save'" (TODO.md L3).
 *
 * The phase-76 shell-view-module contract (the theme.js / tokens.js
 * shape): the router (assets/router.js) lazy-imports this module on
 * FIRST show of #view-settings and calls mount(root) ONCE (mount-once,
 * hide-forever — root is the view's <section id="view-settings">,
 * every DOM lookup scoped to it). The initSharedHeader() call never
 * happens here: in the shell the shared header boots exactly once,
 * via the chat module (app.js) at shell boot.
 *
 * What the panel does:
 *
 *   • gate — fetchIsAdmin() (the SAME cached /api/whoami promise
 *     header.js exports, zero extra requests): admin hides
 *     #settings-gate and reveals #settings-content; anonymous /
 *     token-user keeps the gate (the #nav-settings link is already
 *     hidden by header.js — the gate is the DIRECT-URL case, the
 *     #tokens-gate pattern). No /api/admin/settings request is ever
 *     made outside the admin branch (the router 403s them — the
 *     phase-79 contract).
 *   • load — GET /api/admin/settings → render the 75-row catalogue
 *     in the SERVER's order (GROUPS order — the stable order the
 *     E2E pins against): one <tr> per setting (the group band rows
 *     are created per group) + the ship-rebuilt no-match row, all
 *     through createElement + textContent (this file never builds
 *     HTML — the XSS-safe-by-construction house rule). A failed
 *     fetch keeps the last rendered catalogue (never a blanked panel)
 *     and shows the house error line.
 *   • rows — the Setting cell (the label in a .cell-clip ellipsis
 *     — the phase-156 contract with the full text in the control's
 *     aria-label — + the BOR_* name in <code class="settings-env">
 *     + the literal-text `restart required` .settings-flag for the
 *     boot-wired fields (text, never color alone, B5, with the
 *     title/aria-describedby copy explaining when it applies)),
 *     the Value cell (the control by the server's `type`: int/float
 *     → <input type=number> (step="any" for float), bool → a
 *     true/false <select>, json → a spellcheck=false <textarea>
 *     (the one list[str] field, K2), str → <input type=text> (a
 *     <textarea rows=2> for the CSV/path fields whose value exceeds
 *     40 chars), secret → <input type=password
 *     autocomplete=new-password placeholder="•••••• (stored)"> with
 *     an aria-label naming the env var — an EMPTY secret input
 *     means "leave unchanged" (never an accidental wipe); every
 *     control is id=set-<key> with a <label for>), the Source cell
 *     (the literal-text DB / env / default badge — the color is
 *     decoration, B5), and the Actions cell (the per-row Reset —
 *     disabled with a title when there is nothing to reset or the
 *     field is read-only, LOCKED A3).
 *   • dirty tracking — module-state Map<key, value>: an input/
 *     change marks the row (.is-dirty + the "N unsaved changes"
 *     hint) and enables #settings-save; a row that returns to its
 *     served value un-marks.
 *   • Save — the §7.4 never-stale lifecycle (disabled + aria-busy +
 *     "Saving…", re-enabled on success AND failure — a click can
 *     never leave the button stuck): for each dirty row in DOM
 *     order PUT /api/admin/settings/<key> with { value }; STOP AT
 *     THE FIRST FAILURE (K4) — its server detail lands in
 *     #settings-error (role=alert), the catalogue re-GETs so the
 *     badges show the truth, the remaining rows' edits are
 *     re-applied to the re-rendered controls (they stay in the form
 *     for correction), and focus goes to the offending input. All
 *     good → one #settings-status line `Saved N settings.` (then
 *     role=status) — a saved restart-required row appends "—
 *     applies on the next restart" (the owner is never told
 *     "saved" and then sees nothing change) — + a re-GET so every
 *     badge/value is the settled server state.
 *   • Reset — per row: DELETE /api/admin/settings/<key> → the
 *     status line `BOR_X is back to the environment value.` + a
 *     re-GET.
 *   • Clear all overrides — the house two-step inline confirm
 *     (the history-confirm-* classes, focus moves to the confirm
 *     button, Escape / No cancels) → DELETE /api/admin/settings →
 *     the status line `Cleared N overrides.` (N from the
 *     response) + a re-GET.
 *   • the live brand re-apply (phase 190, task 03 — A2, the second half
 *     of "takes effect on clicking save") — when a save / Reset / Clear
 *     all touched one of the three brand strings (`app_name`,
 *     `input_placeholder`, `footer_text` — the panel's own keys), the
 *     OPEN document is re-branded from a fresh `GET /api/config`
 *     through `window.applyBrandFromConfig` (the ONE pass brand.js owns
 *     and the boot runs — this file never writes the title / brand /
 *     footer / placeholder itself). No brand key in the batch → no
 *     extra request; a failed re-apply leaves the document exactly as
 *     it was (never a blanked brand); the catalogue re-GET stays the
 *     catalogue's own refresh. The Theme tab (theme.js) runs the SAME
 *     shared pass after its own save / reset.
 *   • search — #settings-filter: a case-insensitive substring over
 *     the label + BOR_* name cells, applied on input with NO fetch
 *     (the phase-101 tokens D4 contract) and RE-APPLIED after every
 *     load (the query lives in the input — it survives re-shows,
 *     the phase-77 contract). A group with no visible rows hides
 *     its group row; zero matches with a non-empty query → one
 *     no-match row `No settings match "<query>"` (textContent).
 *   • the kill-switch banner — while overlay_enabled is false
 *     (BOR_SETTINGS_DB=0, D6) the #settings-disabled alert explains
 *     that saving stores the value but it will not take effect
 *     (the mechanism is off, not the panel).
 *
 * Every value is rendered with textContent — this file never builds
 * HTML (the XSS-safe-by-construction house rule; a full-file source
 * pin enforces it).
 */

import { fetchIsAdmin } from "./header.js";

export async function mount(root) {
  /* ---------- view elements (the view's section, scoped to root) ---------- */
  const gateEl = root.querySelector("#settings-gate");
  const contentEl = root.querySelector("#settings-content");
  const disabledBanner = root.querySelector("#settings-disabled");
  const statusEl = root.querySelector("#settings-status");
  const errorEl = root.querySelector("#settings-error");
  const filter = root.querySelector("#settings-filter");
  const tbody = root.querySelector("#settings-tbody");
  const saveBtn = root.querySelector("#settings-save");
  const clearAllBtn = root.querySelector("#settings-clear-all");
  const dirtyHint = root.querySelector("#settings-dirty");

  const SAVE_LABEL = "Save settings";

  /* Module state (the phase-76 mount-once contract — it survives
     every switch): the last settled catalogue (the row meta for the
     save's restart check), the pending edits (key → the value being
     edited), and the in-flight save flag (the §7.4 guard). */
  let lastItems = [];
  const dirty = new Map();
  let saveInFlight = false;
  let clearAllEsc = null; // the armed Escape handler (null = disarmed)

  /* The no-match row (rebuilt into the tbody on every render — the
     <td> text is JS-filled; it is never a data row). */
  const noMatchRow = document.createElement("tr");
  noMatchRow.className = "settings-no-match";
  noMatchRow.hidden = true;
  const noMatchTd = document.createElement("td");
  noMatchTd.colSpan = 4;
  noMatchRow.appendChild(noMatchTd);

  /* ---------- feedback lines (never stale, §7.4) ---------- */

  function announce(message) {
    if (statusEl) statusEl.textContent = message;
  }

  function showError(message) {
    if (!errorEl) return;
    errorEl.textContent = message; // textContent — the server detail is data
    errorEl.hidden = false;
  }

  function clearError() {
    if (!errorEl) return;
    errorEl.textContent = "";
    errorEl.hidden = true;
  }

  /* FastAPI error bodies: a string detail (the house 422s — the
     detail names the offending field) or the validation-error array
     (the first entry's msg). Same extraction as theme.js. */
  async function apiDetail(r, fallback) {
    try {
      const data = await r.json();
      if (Array.isArray(data.detail) && data.detail[0] && data.detail[0].msg) {
        return String(data.detail[0].msg);
      }
      if (typeof data.detail === "string" && data.detail) return data.detail;
    } catch {
      /* non-JSON error body */
    }
    return fallback;
  }

  /* ---------- catalogue render (createElement + textContent only) ---------- */

  const dataRows = () =>
    tbody ? [...tbody.querySelectorAll("tr.settings-row")] : [];

  function makeControl(item) {
    let control;
    if (item.secret) {
      /* LOCKED A4: the secret is write-only — the input starts
         EMPTY (the plaintext never leaves the server); an empty
         value means "leave unchanged" (never an accidental wipe). */
      control = document.createElement("input");
      control.type = "password";
      control.setAttribute("autocomplete", "new-password");
      control.placeholder = "•••••• (stored)";
    } else if (item.type === "int") {
      control = document.createElement("input");
      control.type = "number";
      control.value = item.value;
    } else if (item.type === "float") {
      control = document.createElement("input");
      control.type = "number";
      control.step = "any";
      control.value = item.value;
    } else if (item.type === "bool") {
      control = document.createElement("select");
      for (const opt of ["true", "false"]) {
        const option = document.createElement("option");
        option.value = opt;
        option.textContent = opt;
        control.appendChild(option);
      }
      control.value = item.value;
    } else if (item.type === "json") {
      /* The one list[str] field (K2) — edited as a JSON array in a
         textarea (the server's env-native string form, verbatim). */
      control = document.createElement("textarea");
      control.spellcheck = false;
      control.rows = 2;
      control.value = item.value;
    } else if (item.type === "str" && (item.value || "").length > 40) {
      /* A CSV / path field with a long value — the two-row
         textarea (no single-line clip for 200-char lists). */
      control = document.createElement("textarea");
      control.rows = 2;
      control.value = item.value;
    } else {
      control = document.createElement("input");
      control.type = "text";
      control.setAttribute("autocomplete", "off");
      control.value = item.value;
    }
    control.id = "set-" + item.key;
    control.classList.add("settings-control");
    /* The full (unclipped) label stays reachable: the .cell-clip
       ellipsis is visual only (the phase-156 contract), and the
       secret's aria-label names the env var (the house pattern for
       table-hosted inputs — the Setting cell's label is the
       visible <label for>). */
    control.setAttribute(
      "aria-label",
      item.secret ? item.env_var : `${item.label} — ${item.env_var}`,
    );
    return control;
  }

  function makeRow(item) {
    const tr = document.createElement("tr");
    tr.className = "settings-row";
    tr.dataset.key = item.key;

    /* The Setting cell: the label (the .cell-clip ellipsis — the
       full text is the label's own textContent + the control's
       aria-label), the BOR_* name (presentation only, D1), and —
       when boot-wired (LOCKED A4) — the literal-text flag with
       the when-it-applies copy (title + the shared
       aria-describedby target). */
    const nameTd = document.createElement("td");
    nameTd.className = "settings-name-cell";
    const label = document.createElement("label");
    label.htmlFor = "set-" + item.key;
    const clip = document.createElement("span");
    clip.className = "cell-clip";
    clip.textContent = item.label;
    label.appendChild(clip);
    const env = document.createElement("code");
    env.className = "settings-env";
    env.textContent = item.env_var;
    nameTd.append(label, env);
    if (item.restart_required) {
      const flag = document.createElement("span");
      flag.className = "settings-flag";
      flag.textContent = "restart required"; // text, never color alone (B5)
      flag.title =
        "Applies on the next restart — the app reads this setting once at boot";
      flag.setAttribute("aria-describedby", "settings-restart-desc");
      nameTd.appendChild(flag);
    }
    tr.appendChild(nameTd);

    /* The Value cell: the control by type (see makeControl). */
    const valueTd = document.createElement("td");
    valueTd.className = "settings-value-cell";
    const control = makeControl(item);
    valueTd.appendChild(control);
    tr.appendChild(valueTd);

    /* The Source cell: the literal-text badge (db → "DB", env,
       default — the color is decoration, B5). */
    const srcTd = document.createElement("td");
    const src = document.createElement("span");
    src.className =
      "settings-src " +
      ({ db: "is-db", env: "is-env", default: "is-default" })[item.source];
    src.textContent = item.source === "db" ? "DB" : item.source;
    srcTd.appendChild(src);
    tr.appendChild(srcTd);

    /* The Actions cell: the per-row Reset — disabled with a title
       when there is NOTHING to reset (no saved override) or the
       field is READ-ONLY (LOCKED A3: the engine is built from it /
       the dim is fixed at table creation). */
    const actTd = document.createElement("td");
    actTd.className = "settings-actions-cell";
    const reset = document.createElement("button");
    reset.type = "button";
    reset.className = "settings-reset";
    reset.textContent = "Reset";
    reset.setAttribute("aria-label", `Reset ${item.env_var}`);
    if (!item.overridable) {
      reset.disabled = true;
      reset.title = `read-only — ${item.env_var} is not settable from the database`;
    } else if (!item.has_override) {
      reset.disabled = true;
      reset.title = "no saved override — the environment value is in effect";
    }
    reset.addEventListener("click", () => void resetRow(item.key, item.env_var));
    actTd.appendChild(reset);
    tr.appendChild(actTd);

    /* Dirty tracking (input + change — the select/change pair). */
    control.addEventListener("input", () => markDirty(item, control));
    control.addEventListener("change", () => markDirty(item, control));
    return tr;
  }

  /* GET /api/admin/settings → render the groups in the server's
     order (re-entrant: the tbody is REPLACED — never a duplicate
     set — and the no-match row is re-appended). A FAILED load
     returns before the render (the last catalogue stays) and shows
     the house error line. */
  function render(items) {
    if (!tbody) return;
    const rows = [];
    let currentGroup = null;
    for (const item of items) {
      if (item.group !== currentGroup) {
        currentGroup = item.group;
        const groupRow = document.createElement("tr");
        groupRow.className = "settings-group-row";
        const th = document.createElement("th");
        th.colSpan = 4;
        th.scope = "colgroup";
        th.textContent = item.group;
        groupRow.appendChild(th);
        rows.push(groupRow);
      }
      rows.push(makeRow(item));
    }
    rows.push(noMatchRow);
    tbody.replaceChildren(...rows);
  }

  async function loadSettings() {
    let r;
    try {
      r = await fetch("/api/admin/settings");
    } catch {
      showError("Couldn't load the settings — is the app reachable?");
      return false;
    }
    if (!r.ok) {
      showError("Couldn't load the settings — try again.");
      return false;
    }
    let data;
    try {
      data = await r.json();
    } catch {
      showError("Couldn't load the settings — try again.");
      return false;
    }
    clearError();
    lastItems = data.items;
    /* The kill-switch banner (D6): the mechanism is off, not the
       panel — a save stores the value but it will not take effect. */
    if (disabledBanner) disabledBanner.hidden = data.overlay_enabled;
    render(data.items);
    /* A failed batch keeps the remaining edits in the form (K4):
       re-apply every pending value to the re-rendered control and
       re-mark the row. */
    for (const [key, value] of dirty) {
      const control = root.querySelector("#set-" + key);
      if (!control) continue;
      control.value = value;
      const row = control.closest("tr");
      if (row) row.classList.add("is-dirty");
    }
    applyFilter();
    updateDirtyUI();
    return true;
  }

  /* ---------- dirty tracking (module state) ---------- */

  function markDirty(item, control) {
    /* The served value: the effective value in env-native string
       form — for a MASKED field it is "" (an empty input means
       "leave unchanged", never an accidental wipe). */
    const served = item.secret ? "" : item.value ?? "";
    const value = control.value;
    if (value === served) {
      dirty.delete(item.key);
    } else {
      dirty.set(item.key, value);
    }
    updateDirtyUI();
  }

  function updateDirtyUI() {
    for (const row of dataRows()) {
      row.classList.toggle("is-dirty", dirty.has(row.dataset.key));
    }
    if (dirtyHint) {
      dirtyHint.textContent = dirty.size
        ? `${dirty.size} unsaved changes`
        : "";
    }
    if (saveBtn && !saveInFlight) saveBtn.disabled = dirty.size === 0;
  }

  /* ---------- the client-side search (phase-101 D4 contract) ----------
   * Case-insensitive substring over the label + BOR_* name cells,
   * applied on `input` with NO fetch and re-applied after every
   * load (the query lives in the input — it survives re-shows).
   * A group with no visible rows hides its group row; zero matches
   * with a non-empty query → the one no-match row (textContent). */
  function applyFilter() {
    const query = (filter ? filter.value : "").trim().toLowerCase();
    const children = tbody ? [...tbody.children] : [];
    let visible = 0;
    let currentGroupRow = null;
    const groupVisible = new Map();
    for (const tr of children) {
      if (tr === noMatchRow) continue; // the state row is never a data row
      if (tr.classList.contains("settings-group-row")) {
        currentGroupRow = tr;
        groupVisible.set(tr, false);
        continue;
      }
      const nameCell = tr.querySelector(".settings-name-cell");
      const labelEl = nameCell ? nameCell.querySelector("label") : null;
      const envEl = nameCell
        ? nameCell.querySelector(".settings-env")
        : null;
      const haystack =
        ((labelEl ? labelEl.textContent : "") +
          " " +
          (envEl ? envEl.textContent : "")).toLowerCase();
      const show = query === "" || haystack.includes(query);
      tr.hidden = !show;
      if (show) visible += 1;
      if (currentGroupRow) groupVisible.set(currentGroupRow, true);
    }
    for (const [groupRow, hasVisible] of groupVisible) {
      groupRow.hidden = !hasVisible;
    }
    const noMatch = query !== "" && visible === 0;
    noMatchRow.hidden = !noMatch;
    if (noMatch) {
      noMatchTd.textContent = `No settings match "${
        filter ? filter.value.trim() : ""
      }".`;
    }
  }

  /* ---------- the live brand re-apply (phase 190, task 03 — A2) ----------
   * The phase-168 header contract is "the change should take effect on
   * clicking 'save'" — for the three BRAND strings that means the OPEN
   * document too, not just the catalogue. One pass, ONE owner:
   * brand.js exports the boot's own function as
   * window.applyBrandFromConfig, and this helper feeds it a fresh
   * GET /api/config (the same no-store request the boot makes).
   *
   *   • gated on the key — a save / Reset of any of the ~72 other rows
   *     costs NO extra request and no DOM churn; Clear all passes all
   *     three because clearing hands every one of them back to the
   *     Theme-tab row or the environment;
   *   • the §7.4 guard, EXTENDED not forked — the save itself is already
   *     inside `saveInFlight` (this helper is awaited before that flag
   *     drops, so a second Save can never start mid-re-apply) and the
   *     one flag below covers the settle paths that share the pass, so a
   *     second save / Reset / Clear all never stacks a second fetch;
   *   • never a blanked brand — a non-2xx or an unreachable app returns
   *     WITHOUT touching the DOM (the phase-168 "never a blanked panel"
   *     precedent): the open page keeps its last applied name, footer
   *     and placeholder, and the save's own status / error line stays
   *     the visibility. */
  const BRAND_KEYS = ["app_name", "input_placeholder", "footer_text"];
  let brandReapplyInFlight = false;

  async function reapplyBrand(keys) {
    if (!keys.some((key) => BRAND_KEYS.includes(key))) return; // not a brand row
    if (brandReapplyInFlight) return; // one re-apply at a time (§7.4)
    if (typeof window.applyBrandFromConfig !== "function") return; // brand.js is the owner
    brandReapplyInFlight = true;
    try {
      const r = await fetch("/api/config", { cache: "no-store" });
      if (!r.ok) return; // the brand keeps its last applied state
      window.applyBrandFromConfig(await r.json());
    } catch {
      /* unreachable app or a non-JSON body — nothing is written (the
         brand never blanks; the settle path's own line says it) */
    } finally {
      brandReapplyInFlight = false;
    }
  }

  /* ---------- Save (dirty rows only — stop at the first failure,
     K4; the §7.4 never-stale lifecycle) ---------- */
  async function saveSettings() {
    if (!dirty.size || saveInFlight) return;
    saveInFlight = true;
    if (saveBtn) {
      saveBtn.disabled = true;
      saveBtn.setAttribute("aria-busy", "true");
      saveBtn.textContent = "Saving…";
    }
    clearError();
    const saved = [];
    let failure = null;
    for (const row of dataRows()) {
      const key = row.dataset.key;
      if (!key || !dirty.has(key)) continue;
      const value = dirty.get(key);
      try {
        const r = await fetch(`/api/admin/settings/${key}`, {
          method: "PUT",
          headers: { "Content-Type": "application/json" },
          body: JSON.stringify({ value }),
        });
        if (!r.ok) {
          failure = { key, r };
          break; // stop at the first failure (K4)
        }
        saved.push(key);
        dirty.delete(key);
      } catch {
        failure = { key, r: null };
        break; // the app is unreachable — stop
      }
    }
    if (failure) {
      /* The 422 detail (it names the field) or the house network
         line; the catalogue re-GETs first (the badges show the
         truth, the remaining edits are re-applied — K4), and the
         error is shown AFTER the re-GET (the re-GET's clearError
         must not wipe it — the previous success line is cleared
         with it, so the stale "Saved N settings." never lingers,
         the §7.4 never-stale contract). Focus goes to the
         offending input. */
      await loadSettings();
      if (statusEl) statusEl.textContent = "";
      showError(
        failure.r
          ? await apiDetail(failure.r, "Couldn't save the settings — try again.")
          : "Couldn't save the settings — is the app reachable?",
      );
      const input = root.querySelector("#set-" + failure.key);
      if (input) input.focus();
      /* A brand row that DID land before the failure changed the app
         (K4 saves the prefix) — the open document re-reads it too. */
      await reapplyBrand(saved);
    } else {
      /* One status line (role=status) — a saved restart-required
         row says so (the owner is never told "saved" and then sees
         nothing change). */
      const anyRestart = saved.some(
        (key) => (lastItems.find((i) => i.key === key) || {}).restart_required,
      );
      announce(
        `Saved ${saved.length} settings.` +
          (anyRestart ? " — applies on the next restart" : ""),
      );
      await loadSettings(); // every badge/value is the settled state
      /* …and the brand strings apply to the OPEN document (no reload) —
         additive to the catalogue re-GET above, still inside the
         saveInFlight guard (phase 190, task 03). */
      await reapplyBrand(saved);
    }
    saveInFlight = false;
    if (saveBtn) {
      saveBtn.removeAttribute("aria-busy");
      saveBtn.textContent = SAVE_LABEL;
      saveBtn.disabled = dirty.size === 0;
    }
  }

  /* ---------- the per-row Reset (DELETE the row → env wins) ---------- */
  async function resetRow(key, envVar) {
    let r;
    try {
      r = await fetch(`/api/admin/settings/${key}`, { method: "DELETE" });
    } catch {
      announce(`Couldn't reset ${envVar} — is the app reachable?`);
      return;
    }
    if (!r.ok) {
      announce(`Couldn't reset ${envVar} — try again.`);
      return;
    }
    announce(`${envVar} is back to the environment value.`);
    await loadSettings(); // the badge falls back to env/default
    await reapplyBrand([key]); // …and the open document falls back too
  }

  /* ---------- Clear all overrides (the house two-step inline
     confirm — the history-confirm-* classes; focus to Yes; Escape
     / No cancels) ---------- */
  function restoreClearAll() {
    if (clearAllEsc) {
      document.removeEventListener("keydown", clearAllEsc, true);
      clearAllEsc = null;
    }
    const wrap = root.querySelector(".settings-confirm");
    if (wrap) wrap.replaceWith(clearAllBtn);
    if (clearAllBtn) clearAllBtn.focus();
  }

  async function confirmClearAll(yesBtn, restore) {
    yesBtn.disabled = true; // no double-fire while the request is in flight
    let cleared = null;
    try {
      const r = await fetch("/api/admin/settings", { method: "DELETE" });
      if (!r.ok) {
        announce("Couldn't clear the overrides — try again.");
        restore();
        return;
      }
      const data = await r.json();
      cleared = data.cleared;
    } catch {
      announce("Couldn't clear the overrides — is the app reachable?");
      restore();
      return;
    }
    restore();
    announce(`Cleared ${cleared} overrides.`);
    await loadSettings(); // every badge falls back to env/default
    await reapplyBrand(BRAND_KEYS); // every brand string may have moved
  }

  function showClearAllConfirm() {
    if (!clearAllBtn) return;
    const wrap = document.createElement("span");
    wrap.className = "settings-confirm";
    const label = document.createElement("span");
    label.className = "history-confirm-text";
    label.textContent = "Clear all overrides?";
    const yes = document.createElement("button");
    yes.type = "button";
    yes.className = "history-confirm-yes";
    yes.textContent = "Yes";
    const no = document.createElement("button");
    no.type = "button";
    no.className = "history-confirm-no";
    no.textContent = "No";
    yes.addEventListener("click", () => void confirmClearAll(yes, restoreClearAll));
    no.addEventListener("click", restoreClearAll);
    wrap.append(label, yes, no);
    clearAllBtn.replaceWith(wrap);
    yes.focus(); // the confirm pair takes over the focus
    /* Escape cancels (the task contract — the capture phase so the
       page's own Esc handlers never race it). */
    clearAllEsc = (e) => {
      if (e.key === "Escape") {
        e.stopPropagation();
        restoreClearAll();
      }
    };
    document.addEventListener("keydown", clearAllEsc, true);
  }

  /* ---------- view boot (phase 168 task 05) ----------
   * The shared header is NOT booted here — in the shell it runs
   * exactly once, via the chat module (app.js) at shell boot. The
   * gate reads fetchIsAdmin() — the SAME cached whoami promise the
   * header uses (zero extra requests). Anonymous / token-user: the
   * gate in, the content out — and NO /api/admin/settings request
   * at all (the router 403s them — the phase-79 contract). */
  if (!(await fetchIsAdmin())) {
    if (gateEl) gateEl.hidden = false;
    if (contentEl) contentEl.hidden = true;
    return;
  }
  if (gateEl) gateEl.hidden = true;
  if (contentEl) contentEl.hidden = false;

  /* Bindings — armed in the ADMIN branch only (like the refresh
     listener): Save (the §7.4 lifecycle), Clear all (the two-step
     confirm), the client-side search (NO fetch). */
  if (saveBtn) saveBtn.addEventListener("click", () => void saveSettings());
  if (clearAllBtn) clearAllBtn.addEventListener("click", showClearAllConfirm);
  if (filter) filter.addEventListener("input", () => applyFilter());

  /* Phase 77 (the re-show refresh contract): a user-initiated
     re-show of this already-mounted view makes the router dispatch
     bor:view-refresh on the section — re-run the load then (the
     tab always shows the settled server state when re-shown; the
     search query survives — it lives in the input). Armed ONLY
     here, after the whoami gate passed. `started` flips true once
     the first loadSettings() is made, so the listener can only
     ever re-run a load the mount already did. */
  let started = false;
  root.addEventListener("bor:view-refresh", () => {
    if (started) void loadSettings();
  });
  started = true;
  void loadSettings(); // the first load (the catalogue)
}