brain-of-reese/frontend/assets/shared.js

/* Brain of Reese — the anonymous shared conversation page (phase 51,
 * task 03).
 *
 * /shared/<token> (owner-locked 2026-08-29, TODO.md L6): anyone with
 * the link sees the conversation READ-ONLY — zero interactive controls
 * (no composer, no Save/Share/Tune/Retry, no document access). The
 * page fetches GET /api/shared/<token> (public — the token IS the
 * credential, no admin dependency) and renders the SAME record shape
 * the chat page uses (phase 14 bor.chat.v1 — { who, text, sources?,
 * deflected?, suggestions?, thinking?, tools?, stopped? }):
 *
 *   • user  → the .msg.user bubble (markdown, escape-first);
 *   • brain → the .msg.brain bubble: the optional thinking block
 *     restored COLLAPSED (the phase-17 restore convention — a guest
 *     can still expand it; reading is not mutating), the tool lines
 *     in saved order (phase 37), the is-deflected treatment + the
 *     "Maybe try" chips as PLAIN SPAN text (a guest tapping a chip
 *     has nowhere to go — owner-locked zero controls), the source
 *     chips as PLAIN TEXT spans (no href, no modal wiring — the
 *     documents API is admin-only, so a guest cannot open documents),
 *     and the stopped note (phase 48) when the turn was user-stopped.
 *
 * Per-page duplication house style (history.js keeps its own clipboard
 * helper, the chat page's stays in app.js): this file carries its own
 * small copies of the chat page's message-fragment builders — the
 * thinking block, the tool lines, the stopped note, the chip rows.
 * Nothing is imported from app.js (a page script is never imported by
 * another page; header.js is the only cross-page module).
 *
 * Failure contract: a malformed or missing token in the URL → the
 * invalid state shows immediately with NO fetch of any kind (not even
 * whoami — the header ships in its guest state, which is already
 * correct); a 404 (wrong or revoked token), a network failure, or a
 * malformed body → the invalid state (the h1 keeps its fallback), no
 * data is rendered, and there is no error banner on this page (zero
 * controls — the muted invalid card is the whole failure UI).
 *
 * The header works for guests: initSharedHeader() runs the cached
 * whoami (anonymous → the admin-only links stay hidden, the Sign in
 * link is shown) and rewrites ?next= to the current pathname for a
 * signed-in admin; the guest's static fallback is ?next=/ — a guest
 * signing in from a shared page returns to the app root (see
 * shared.html).
 *
 * All DOM ids match frontend/shared.html.
 */

import { bindSharedHeaderControls, initSharedHeader } from "./header.js";

// The shared header's control bindings (sign-out / mobile hamburger) —
// EXPLICIT init, once per document (header.js is bundle-inlined per
// entry; import-time side effects would double-bind — 2026-09-08 fix).
bindSharedHeaderControls();

const titleEl = document.querySelector("#shared-title");
const noteEl = document.querySelector(".shared-note");
const messagesEl = document.querySelector("#messages");
const invalidEl = document.querySelector("#shared-invalid");

/* Phase 39: the display name resolves from one place — window.BOR_BRAND
 * (the classic assets/brand.js sets it at parse time; its /api/config
 * fetch refreshes it). Read LAZILY (a function, not a const string):
 * the note set after the fetch lands carries the configured name; the
 * literal is only the no-config fallback. */
const brand = () => window.BOR_BRAND || "Brain of Reese";

/* ---------- the token (from the URL) ----------
 * The last path segment of /shared/<token>. A malformed or missing
 * token (a path without a final segment, or a non-uuid segment) →
 * null: the boot shows the invalid state immediately and makes NO
 * fetch of any kind (the server's page route 404s a hand-typed
 * /shared/garbage anyway — the client gate keeps the no-fetch rule
 * and renders the page's own invalid state instead of a JSON error). */
const TOKEN_RE = /^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i;

export function parseSharedToken() {
  const segments = window.location.pathname.split("/").filter(Boolean);
  const last = segments[segments.length - 1] || "";
  return TOKEN_RE.test(last) ? last : null;
}

/* ---------- the invalid / revoked state ----------
 * The one failure UI on the page: the centered muted card (ship-
 * hidden in the markup, revealed here). The h1 keeps its static
 * fallback, the conversation section stays empty — no data rendered,
 * no banner. */
export function showInvalid() {
  if (invalidEl) invalidEl.hidden = false;
}

/* ---------- avatar glyphs (duplicated from app.js, phase 08) ----------
 * Inline SVG as string constants so the message renderer shares the
 * exact marks the chat page uses. currentColor lets the CSS theme the
 * stroke (brand-ink for Brain, ink-soft for the user). */
const BRAIN_AVATAR =
  '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.7" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><rect x="6.5" y="6.5" width="11" height="11" rx="2.5"/><circle cx="12" cy="12" r="1.9" fill="currentColor" stroke="none"/><path d="M9.5 6.5V3.8M14.5 6.5V3.8M9.5 20.2v-2.7M14.5 20.2v-2.7M6.5 9.5H3.8M6.5 14.5H3.8M20.2 9.5h-2.7M20.2 14.5h-2.7"/></svg>';

const USER_AVATAR =
  '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="1.7" stroke-linecap="round" aria-hidden="true"><circle cx="12" cy="8" r="3.6"/><path d="M4.8 20.2c.9-3.9 3.8-6 7.2-6s6.3 2.1 7.2 6"/></svg>';

/* ---------- messages (read-only) ----------
 * The SAME .msg/.msg-body/.bubble structure the chat page renders, so
 * the existing CSS applies unchanged. No scroll intent (a guest lands
 * where the browser puts them — no composer to reveal), no empty
 * state to hide (the section is empty by construction until records
 * are appended). */
function addSharedMessage(who, html) {
  const wrap = document.createElement("div");
  wrap.className = `msg ${who}`;
  wrap.innerHTML = `
    <span class="avatar" aria-hidden="true">${who === "brain" ? BRAIN_AVATAR : USER_AVATAR}</span>
    <div class="msg-body">
      <div class="bubble">${html}</div>
    </div>`;
  messagesEl.appendChild(wrap);
  return wrap;
}

/* The thinking block (phase 17) — the local copy of the chat page's
 * restore path: the model's reasoning ABOVE the answer bubble,
 * restored COLLAPSED (the phase-17 restore convention — the live path
 * opens it while streaming; a shared chat is a finished conversation,
 * so it lands closed). Native details/summary — expanding is reading,
 * not mutating. The reasoning text is stored RAW, so it goes through
 * the same escape-first global renderMarkdown as the answer. */
function addThinkingBlock(wrap, thinking) {
  const body = wrap.querySelector(".msg-body");
  if (!body) return;
  const block = document.createElement("details");
  block.className = "thinking";
  block.open = false; // restored COLLAPSED
  const summary = document.createElement("summary");
  summary.textContent = "Thinking";
  const textEl = document.createElement("div");
  textEl.className = "thinking-text";
  textEl.innerHTML = renderMarkdown(thinking); // escape-first, XSS-safe
  block.append(summary, textEl);
  body.insertBefore(block, body.querySelector(".bubble"));
}

/* Tool-call lines (phase 37; phase 70 remapped the tool names to the
 * harness surface ls / read(path) / grep(pattern, path?)) — the local
 * copy of the chat page's appendToolLine: one visible "calling tool"
 * row per saved {name, argument} record, in saved order, above the
 * answer. Every argument (path / pattern / source scope) goes through
 * textContent, so nothing HTML-shaped can come from storage. Lines
 * are not interactive (no focus targets). Phase 70: the NEW names
 * render (read → the Reading line, grep → the Searching-for line,
 * ls → the Listing-documents line, scoped ls → the
 * Listing-documents-in-<scope> line), and the pre-phase-70 names
 * (read_document / search_documents / list_documents) still render
 * exactly as before — a row saved before the remap keeps its exact
 * line (no migration). The content marks are the exact app.js
 * template strings — the frontend emoji guard (tests/integration/
 * test_api.py) strips precisely those literals in this file, as in
 * app.js.
 *
 * Phase 95 (task 02): the truncation marker rides the SAME stored
 * record the chat page uses — a {name, argument, truncated,
 * chars_shown, chars_total} entry (the live `tool_result` frame's stamp,
 * persisted with the turn) re-renders the identical " (truncated —
 * showing N of M chars)" span next to its Reading line, so a shared
 * page shows the truncation pixel-identically to the chat page (the
 * phase-50 restore contract). A record saved before phase 95 (no
 * fields) renders exactly as before (no marker, no migration).
 * createElement + textContent only — nothing HTML-shaped from storage. */
function addToolLines(wrap, tools) {
  if (!Array.isArray(tools) || !tools.length) return;
  const body = wrap.querySelector(".msg-body");
  if (!body) return;
  const container = document.createElement("div");
  container.className = "tool-calls";
  container.setAttribute("role", "list");
  container.setAttribute("aria-label", "Tool calls");
  for (const t of tools) {
    if (!t || typeof t.name !== "string") continue;
    const line = document.createElement("span");
    line.className = "tool-call";
    line.setAttribute("role", "listitem");
    const argument =
      typeof t.argument === "string" && t.argument ? t.argument : null;
    // Phase 70: new names first, legacy names kept — a conversation
    // saved before the remap renders byte-identical (no migration).
    if ((t.name === "read" || t.name === "read_document") && argument) {
      line.textContent = "📄 Reading ";
      const code = document.createElement("code");
      code.textContent = argument; // the path is data, never markup
      line.appendChild(code);
    } else if (
      (t.name === "grep" || t.name === "search_documents") && argument
    ) {
      line.textContent = "🔎 Searching for ";
      const code = document.createElement("code");
      code.textContent = argument; // the pattern is data, never markup
      line.appendChild(code);
    } else if (t.name === "ls" && argument) {
      line.textContent = "🔎 Listing documents in ";
      const code = document.createElement("code");
      code.textContent = argument; // the source scope is data, never markup
      line.appendChild(code);
    } else {
      line.textContent = "🔎 Listing documents";
    }
    container.appendChild(line);
    // Phase 95: the stored truncation record — the same marker the chat
    // page's restore path renders (plain integers, no separators);
    // only argument-bearing (Reading) lines can carry it.
    if (t.truncated && argument) {
      const note = document.createElement("span");
      note.className = "truncated-note";
      note.textContent =
        " (truncated — showing " + (Number(t.chars_shown) || 0) + " of " + (Number(t.chars_total) || 0) + " chars)";
      line.appendChild(note);
    }
  }
  body.insertBefore(container, body.querySelector(".bubble"));
}

/* "Maybe try:" chips under a deflected bubble (honesty gate, phase
 * 04) — PLAIN SPAN text, not buttons (owner-locked 2026-08-29: a
 * guest tapping a chip has nowhere to go — zero interactive
 * controls). Same .suggestion-chip pill look as the chat page; the
 * shared-page CSS kills the pointer (pointer-events: none, scoped to
 * .shared-shell — the chat page's interactive chips are untouched). */
function addMaybeTry(wrap, suggestions) {
  if (!Array.isArray(suggestions) || !suggestions.length) return;
  const body = wrap.querySelector(".msg-body");
  if (!body) return;
  const group = document.createElement("div");
  group.className = "maybe-try";
  group.setAttribute("role", "list");
  group.setAttribute("aria-label", "Maybe try");
  const label = document.createElement("span");
  label.className = "visually-hidden";
  label.textContent = "Maybe try:";
  group.appendChild(label);
  for (const item of suggestions) {
    const text = String(item || "").trim();
    if (!text) continue;
    const chip = document.createElement("span");
    chip.className = "suggestion-chip";
    chip.setAttribute("role", "listitem");
    chip.textContent = text; // raw text — never markup
    group.appendChild(chip);
  }
  body.appendChild(group);
}

/* Source chips (mono, source/path) under a brain bubble — PLAIN TEXT
 * spans: no href, no modal wiring, no click handler (owner-locked:
 * guests cannot open documents — the documents API is admin-only,
 * phase 16). Same .source-chip pill look as the chat page; the
 * shared-page CSS kills the pointer, scoped to .shared-shell. */
function addSources(wrap, sources) {
  if (!Array.isArray(sources) || !sources.length) return;
  const body = wrap.querySelector(".msg-body");
  if (!body) return;
  const meta = document.createElement("div");
  meta.className = "msg-meta";
  meta.setAttribute("role", "list");
  meta.setAttribute("aria-label", "Sources");
  for (const s of sources) {
    if (!s || typeof s.source !== "string" || typeof s.path !== "string") continue;
    const label = `${s.source}/${s.path}`;
    const chip = document.createElement("span");
    chip.className = "source-chip";
    chip.setAttribute("role", "listitem");
    chip.textContent = label; // the path is data — never markup
    chip.title = label;
    meta.appendChild(chip);
  }
  body.appendChild(meta);
}

/* The "Stopped" note (phase 48) — the local copy of the chat page's
 * appendStoppedNote: the non-interactive meta-row mark on a
 * user-stopped brain bubble (the partial answer is what the owner
 * shared). Reuses the .msg-meta row when one exists (the source
 * chips' row) so the note joins it as a listitem, ARIA-valid. */
function addStoppedNote(wrap) {
  const body = wrap?.querySelector?.(".msg-body");
  if (!body) return;
  let meta = body.querySelector(".msg-meta");
  if (!meta) {
    meta = document.createElement("div");
    meta.className = "msg-meta";
    body.appendChild(meta);
  }
  if (meta.querySelector(".stopped-note")) return; // one per bubble
  const note = document.createElement("span");
  note.className = "stopped-note";
  if (meta.getAttribute("role") === "list") note.setAttribute("role", "listitem");
  note.innerHTML =
    '<svg aria-hidden="true" viewBox="0 0 24 24" fill="currentColor"><rect x="6.5" y="6.5" width="11" height="11" rx="2"/></svg>';
  const label = document.createElement("span");
  label.textContent = "Stopped";
  note.appendChild(label);
  meta.appendChild(note);
}

/* One stored record through the SAME .msg structure the chat page
 * uses (pixel-parity with the chat page's restore path): user → the
 * .msg.user bubble; brain → the .msg.brain bubble with the optional
 * thinking block (restored COLLAPSED — phase 17), the tool lines,
 * the deflection treatment + the plain-text "Maybe try" chips, the
 * plain-text source chips, and the stopped note. NO interactive
 * markup is ever created here — no buttons, no forms, no links, no
 * click handlers (owner-locked: zero controls). Markdown goes
 * through the global escape-first renderMarkdown (markdown.js): the
 * stored payloads are raw text, so the renderer's XSS safety applies
 * unchanged. */
function renderSharedMessage(m) {
  if (m.who === "user") {
    addSharedMessage("user", renderMarkdown(m.text));
    return;
  }
  const wrap = addSharedMessage("brain", renderMarkdown(m.text));
  if (typeof m.thinking === "string" && m.thinking) {
    addThinkingBlock(wrap, m.thinking);
  }
  addToolLines(wrap, m.tools);
  if (m.deflected) {
    wrap.classList.add("is-deflected");
    addMaybeTry(wrap, m.suggestions);
  }
  addSources(wrap, m.sources);
  if (m.stopped) addStoppedNote(wrap);
}

/* ---------- the public read ----------
 * GET /api/shared/<token> — no admin dependency (the token IS the
 * credential). Returns the SharedChatOut snapshot (title + messages)
 * or null: a 404 (wrong or revoked token — one message server-side,
 * no enumeration), a network failure, or a malformed body all
 * collapse to null → the invalid state. */
async function fetchSharedChat(token) {
  let res;
  try {
    res = await fetch(`/api/shared/${token}`);
  } catch {
    return null; // network failure
  }
  if (!res.ok) return null; // 404 (wrong/revoked) / 5xx
  let data;
  try {
    data = await res.json();
  } catch {
    return null; // malformed body
  }
  return data && Array.isArray(data.messages) ? data : null;
}

/* The 200 path: the h1 gets the shared chat's title (the static
 * fallback stays when the title is missing/blank) and every record
 * renders through renderSharedMessage. The same defensive filter as
 * the chat page's restore keeps a corrupted stored row from
 * poisoning the render (nothing HTML-shaped, ever). */
function renderSharedChat(data) {
  const title = typeof data.title === "string" ? data.title.trim() : "";
  if (title) titleEl.textContent = title;
  const messages = data.messages.filter(
    (m) =>
      m &&
      (m.who === "user" || m.who === "brain") &&
      typeof m.text === "string" &&
      m.text.length > 0
  );
  for (const m of messages) renderSharedMessage(m);
}

/* Boot: the brand note first (call-time resolution — the classic
 * brand.js already set the synchronous default), then the token. A
 * malformed or missing token shows the invalid state immediately —
 * NO fetch of any kind (not even whoami: the header ships in its
 * guest state, which is already correct for a bad URL). A well-
 * formed token runs the shared header init (guests: whoami
 * anonymous, the admin-only links stay hidden) and then the public
 * read; a null read (404 / network / malformed) shows the invalid
 * state, and a 200 renders the conversation read-only. */
(async () => {
  if (noteEl) noteEl.textContent = `Shared via ${brand()} — read-only.`;
  const token = parseSharedToken();
  if (!token) {
    showInvalid();
    return;
  }
  await initSharedHeader();
  const data = await fetchSharedChat(token);
  if (!data) {
    showInvalid();
    return;
  }
  renderSharedChat(data);
})();