feat: implement R42 chat infrastructure with Anthropic API integration and custom design system

src/components/chat/ChatLauncher.jsx

@@ -0,0 +1,59 @@
+import React, { useEffect, useState } from 'react';
+import Mark from '../ui/Mark';
+import ChatWindow from './ChatWindow';
+import { useApp } from '../../store/AppContext';
+import { storage } from '../../lib/storage';
+import { STRINGS } from './prompts';
+import './chat.css';
+
+const QUIZ_EVENT = 'respellion:quiz-state';
+
+/**
+ * Global floating launcher. Hidden while a quiz is active (set via
+ * the `respellion:quiz-state` window event from Testen.jsx) to protect
+ * quiz integrity.
+ */
+export default function ChatLauncher() {
+  const { state } = useApp();
+  const user = state.currentUser;
+  const isAdmin = user?.role === 'admin';
+
+  const [open, setOpen] = useState(false);
+  const [quizActive, setQuizActive] = useState(() => {
+    if (!user) return false;
+    return storage.get(`quiz:active:${user.id}`, false) === true;
+  });
+
+  useEffect(() => {
+    if (!user) return;
+    setQuizActive(storage.get(`quiz:active:${user.id}`, false) === true);
+  }, [user]);
+
+  useEffect(() => {
+    const handler = (e) => {
+      setQuizActive(Boolean(e?.detail?.active));
+      if (e?.detail?.active) setOpen(false);
+    };
+    window.addEventListener(QUIZ_EVENT, handler);
+    return () => window.removeEventListener(QUIZ_EVENT, handler);
+  }, []);
+
+  if (!user || quizActive) return null;
+
+  return (
+    <>
+      {open && (
+        <ChatWindow user={user} isAdmin={isAdmin} onClose={() => setOpen(false)} />
+      )}
+      <button
+        type="button"
+        className={`r42-fab ${open ? 'open' : ''}`}
+        onClick={() => setOpen(o => !o)}
+        aria-label={open ? STRINGS.closeAria : STRINGS.openAria}
+        aria-expanded={open}
+      >
+        <Mark state="idle" size={open ? 28 : 36} brace="#ECE9E9" letter="#ECE9E9" />
+      </button>
+    </>
+  );
+}

src/components/chat/ChatMessage.jsx

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+import React from 'react';
+import Mark from '../ui/Mark';
+import { STRINGS } from './prompts';
+
+/**
+ * Renders one message bubble. Assistant messages may include a `suggestion`
+ * (validated graph delta) — the user confirms or rejects inline.
+ */
+export default function ChatMessage({ msg, onAcceptSuggestion, onRejectSuggestion }) {
+  if (msg.role === 'user') {
+    return (
+      <div className="r42-msg me">
+        <div className="bub">{msg.content}</div>
+      </div>
+    );
+  }
+
+  if (msg.role === 'error') {
+    return (
+      <div className="r42-msg error">
+        <div className="av-sm">
+          <Mark state="error" size={20} brace="#ECE9E9" letter="#ECE9E9" />
+        </div>
+        <div className="bub">{msg.content}</div>
+      </div>
+    );
+  }
+
+  // assistant
+  const s = msg.suggestion;
+  return (
+    <div className="r42-msg">
+      <div className="av-sm">
+        <Mark state="idle" size={20} brace="#ECE9E9" letter="#ECE9E9" />
+      </div>
+      <div>
+        <div className="bub">{msg.content}</div>
+        {s && (
+          <div className="r42-suggestion" role="group" aria-label="Voorstel kennisgraaf">
+            <div className="r42-suggestion-title">{STRINGS.suggestionTitle}</div>
+            {s.reason && <div style={{ marginBottom: 6 }}>{s.reason}</div>}
+            {(s.topics.length > 0 || s.relations.length > 0) && (
+              <ul className="r42-suggestion-items">
+                {s.topics.map(t => (
+                  <li key={`t-${t.id}`}>
+                    <strong>{t.label}</strong>{' '}
+                    <span style={{ opacity: 0.7 }}>({t.type})</span>
+                  </li>
+                ))}
+                {s.relations.map((r, i) => (
+                  <li key={`r-${i}`}>
+                    <code>{r.source}</code>{' '}
+                    <span style={{ opacity: 0.7 }}>{r.type}</span>{' → '}
+                    <code>{r.target}</code>
+                  </li>
+                ))}
+              </ul>
+            )}
+            {s.status === 'pending' ? (
+              <div className="r42-suggestion-actions">
+                <button
+                  type="button"
+                  className="primary"
+                  onClick={() => onAcceptSuggestion(msg.id)}
+                >
+                  {STRINGS.suggestionAccept}
+                </button>
+                <button type="button" onClick={() => onRejectSuggestion(msg.id)}>
+                  {STRINGS.suggestionReject}
+                </button>
+              </div>
+            ) : (
+              <div className="r42-suggestion-status">
+                {s.status === 'applied' && STRINGS.suggestionAppliedAdmin}
+                {s.status === 'queued' && STRINGS.suggestionQueuedUser}
+                {s.status === 'rejected' && STRINGS.suggestionDismissed}
+              </div>
+            )}
+          </div>
+        )}
+      </div>
+    </div>
+  );
+}

src/components/chat/ChatWindow.jsx

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+import React, { useCallback, useEffect, useRef, useState } from 'react';
+import Mark from '../ui/Mark';
+import ChatMessage from './ChatMessage';
+import { useChat } from './useChat';
+import { kbStore } from '../../lib/kbStore';
+import { BOT_NAME, STRINGS } from './prompts';
+
+export default function ChatWindow({ user, isAdmin, onClose }) {
+  const { messages, isThinking, send } = useChat({ user, isAdmin });
+  const [draft, setDraft] = useState('');
+  const bodyRef = useRef(null);
+  const inputRef = useRef(null);
+  const [decided, setDecided] = useState({}); // { [msgId]: 'applied'|'queued'|'rejected' }
+
+  // Scroll to bottom when new messages arrive
+  useEffect(() => {
+    if (bodyRef.current) {
+      bodyRef.current.scrollTop = bodyRef.current.scrollHeight;
+    }
+  }, [messages, isThinking]);
+
+  // Focus the input on open
+  useEffect(() => {
+    inputRef.current?.focus();
+  }, []);
+
+  // Close on Escape
+  useEffect(() => {
+    const onKey = (e) => {
+      if (e.key === 'Escape') onClose?.();
+    };
+    window.addEventListener('keydown', onKey);
+    return () => window.removeEventListener('keydown', onKey);
+  }, [onClose]);
+
+  const handleSubmit = (e) => {
+    e.preventDefault();
+    if (!draft.trim() || isThinking) return;
+    send(draft);
+    setDraft('');
+  };
+
+  const handleAccept = useCallback(async (msgId) => {
+    const msg = messages.find(m => m.id === msgId);
+    if (!msg?.suggestion) return;
+    if (isAdmin) {
+      await kbStore.applyDelta(msg.suggestion);
+      setDecided(prev => ({ ...prev, [msgId]: 'applied' }));
+    } else {
+      kbStore.appendSuggestion({
+        ...msg.suggestion,
+        proposedBy: user?.id,
+        proposedByName: user?.name,
+      });
+      setDecided(prev => ({ ...prev, [msgId]: 'queued' }));
+    }
+  }, [messages, isAdmin, user]);
+
+  const handleReject = useCallback((msgId) => {
+    setDecided(prev => ({ ...prev, [msgId]: 'rejected' }));
+  }, []);
+
+  const renderedMessages = messages.map(m => {
+    if (!m.suggestion) return m;
+    const status = decided[m.id] || m.suggestion.status || 'pending';
+    return { ...m, suggestion: { ...m.suggestion, status } };
+  });
+
+  return (
+    <div
+      className="r42-window"
+      role="dialog"
+      aria-label={`${BOT_NAME} chatbot`}
+      aria-modal="false"
+    >
+      <header className="r42-window-hd">
+        <div className="av">
+          <Mark state={isThinking ? 'typing' : 'idle'} size={28} brace="#ECE9E9" letter="#ECE9E9" />
+        </div>
+        <div className="r42-window-hd-text">
+          <div className="r42-window-hd-name">{BOT_NAME}</div>
+          <div className="r42-window-hd-status"><i /> {STRINGS.status}</div>
+        </div>
+        <button
+          type="button"
+          className="r42-window-hd-x"
+          onClick={onClose}
+          aria-label={STRINGS.closeAria}
+        >
+          ×
+        </button>
+      </header>
+
+      <div className="r42-window-body" ref={bodyRef}>
+        {renderedMessages.map(m => (
+          <ChatMessage
+            key={m.id}
+            msg={m}
+            onAcceptSuggestion={handleAccept}
+            onRejectSuggestion={handleReject}
+          />
+        ))}
+        {isThinking && (
+          <div className="r42-msg">
+            <div className="av-sm">
+              <Mark state="typing" size={20} brace="#ECE9E9" letter="#ECE9E9" />
+            </div>
+            <div className="bub" style={{ background: 'transparent', border: 'none', padding: '6px 0' }}>
+              <Mark state="typing" size={28} brace="#1F5560" letter="#1F5560" />
+            </div>
+          </div>
+        )}
+      </div>
+
+      <form className="r42-window-input" onSubmit={handleSubmit}>
+        <input
+          ref={inputRef}
+          type="text"
+          value={draft}
+          onChange={(e) => setDraft(e.target.value)}
+          placeholder={STRINGS.placeholder}
+          disabled={isThinking}
+          aria-label={STRINGS.placeholder}
+        />
+        <button type="submit" disabled={isThinking || !draft.trim()}>
+          {STRINGS.send}
+        </button>
+      </form>
+    </div>
+  );
+}

src/components/chat/chat.css

@@ -0,0 +1,233 @@
+/* R42 chatbot — FAB + chat window */
+
+.r42-fab {
+  position: fixed;
+  right: 24px;
+  bottom: 80px;
+  width: 64px;
+  height: 64px;
+  border-radius: var(--r-pill);
+  background: var(--teal-900);
+  display: grid;
+  place-items: center;
+  box-shadow: var(--shadow-pill);
+  cursor: pointer;
+  transition: transform 0.2s ease, box-shadow 0.2s ease;
+  border: 2px solid var(--cream);
+  z-index: 60;
+  padding: 0;
+}
+.r42-fab:hover { transform: translateY(-2px); }
+.r42-fab:focus-visible {
+  outline: 2px solid var(--purple);
+  outline-offset: 3px;
+}
+.r42-fab.open {
+  bottom: calc(80px + 480px - 56px);
+  width: 48px;
+  height: 48px;
+}
+
+@media (min-width: 768px) {
+  .r42-fab { bottom: 24px; }
+  .r42-fab.open { bottom: calc(24px + 480px - 56px); }
+}
+
+.r42-window {
+  position: fixed;
+  right: 24px;
+  bottom: 80px;
+  width: min(380px, calc(100vw - 32px));
+  height: min(480px, calc(100vh - 120px));
+  background: var(--paper);
+  border-radius: var(--r-md);
+  border: 1px solid rgba(31, 85, 96, 0.06);
+  box-shadow: var(--shadow-pill);
+  display: flex;
+  flex-direction: column;
+  overflow: hidden;
+  z-index: 60;
+}
+@media (min-width: 768px) {
+  .r42-window { bottom: 24px; }
+}
+
+.r42-window-hd {
+  background: var(--teal-900);
+  color: var(--cream);
+  padding: var(--s-3) var(--s-4);
+  display: flex;
+  align-items: center;
+  gap: var(--s-3);
+  flex-shrink: 0;
+}
+.r42-window-hd .av {
+  width: 36px;
+  height: 36px;
+  border-radius: var(--r-pill);
+  background: var(--teal);
+  display: grid;
+  place-items: center;
+  flex-shrink: 0;
+}
+.r42-window-hd-text { display: flex; flex-direction: column; gap: 2px; min-width: 0; }
+.r42-window-hd-name { font: 600 14px/1 var(--font-sans); }
+.r42-window-hd-status {
+  font: 500 var(--t-label)/1 var(--font-mono);
+  letter-spacing: var(--label-ls);
+  text-transform: uppercase;
+  color: rgba(236, 233, 233, 0.6);
+  display: flex;
+  align-items: center;
+  gap: 6px;
+}
+.r42-window-hd-status i {
+  width: 5px;
+  height: 5px;
+  border-radius: 999px;
+  background: var(--sage);
+}
+.r42-window-hd-x {
+  margin-left: auto;
+  color: rgba(236, 233, 233, 0.7);
+  background: transparent;
+  border: none;
+  font-size: 22px;
+  line-height: 1;
+  cursor: pointer;
+  padding: 4px 8px;
+  border-radius: var(--r-sm);
+}
+.r42-window-hd-x:hover { background: rgba(236, 233, 233, 0.1); }
+
+.r42-window-body {
+  flex: 1;
+  padding: var(--s-4);
+  background: var(--cream);
+  display: flex;
+  flex-direction: column;
+  gap: var(--s-3);
+  overflow-y: auto;
+}
+
+.r42-msg { display: flex; gap: var(--s-2); align-items: flex-end; }
+.r42-msg .av-sm {
+  width: 26px;
+  height: 26px;
+  border-radius: var(--r-pill);
+  background: var(--teal-900);
+  display: grid;
+  place-items: center;
+  flex-shrink: 0;
+}
+.r42-msg .bub {
+  background: var(--paper);
+  border-radius: 16px 16px 16px 4px;
+  padding: 10px 14px;
+  font: 400 14px/1.45 var(--font-sans);
+  color: var(--ink);
+  max-width: 250px;
+  border: 1px solid rgba(31, 85, 96, 0.06);
+  word-wrap: break-word;
+}
+.r42-msg.me { justify-content: flex-end; }
+.r42-msg.me .bub {
+  background: var(--teal);
+  color: var(--cream);
+  border: none;
+  border-radius: 16px 16px 4px 16px;
+}
+.r42-msg.error .bub {
+  background: #fee2e2;
+  color: #991b1b;
+  border: 1px solid #fecaca;
+}
+
+.r42-suggestion {
+  margin-top: var(--s-2);
+  padding: 10px 12px;
+  background: rgba(92, 29, 216, 0.08);
+  border: 1px solid rgba(92, 29, 216, 0.2);
+  border-radius: var(--r-sm);
+  font: 400 13px/1.4 var(--font-sans);
+  color: var(--ink);
+}
+.r42-suggestion-title {
+  font-weight: 600;
+  color: var(--purple);
+  margin-bottom: 6px;
+  display: flex;
+  align-items: center;
+  gap: 4px;
+}
+.r42-suggestion-items {
+  margin: 6px 0 10px;
+  padding-left: 16px;
+  list-style: disc;
+}
+.r42-suggestion-items li { margin: 2px 0; }
+.r42-suggestion-actions {
+  display: flex;
+  gap: 6px;
+}
+.r42-suggestion-actions button {
+  flex: 1;
+  padding: 6px 10px;
+  border-radius: var(--r-pill);
+  border: 1px solid rgba(92, 29, 216, 0.3);
+  font: 600 12px/1 var(--font-sans);
+  cursor: pointer;
+  background: var(--paper);
+  color: var(--purple);
+  transition: background 0.15s ease, color 0.15s ease;
+}
+.r42-suggestion-actions button.primary {
+  background: var(--purple);
+  color: var(--cream);
+  border-color: var(--purple);
+}
+.r42-suggestion-actions button.primary:hover { background: var(--purple-700); }
+.r42-suggestion-actions button:not(.primary):hover { background: rgba(92, 29, 216, 0.1); }
+.r42-suggestion-status {
+  margin-top: 6px;
+  font: 500 11px/1 var(--font-mono);
+  letter-spacing: var(--label-ls);
+  text-transform: uppercase;
+  color: var(--fg-muted);
+}
+
+.r42-window-input {
+  padding: var(--s-3) var(--s-4);
+  background: var(--paper);
+  border-top: 1px solid rgba(31, 85, 96, 0.06);
+  display: flex;
+  align-items: center;
+  gap: var(--s-2);
+  flex-shrink: 0;
+}
+.r42-window-input input {
+  flex: 1;
+  background: var(--cream);
+  border: none;
+  outline: none;
+  border-radius: var(--r-pill);
+  padding: 10px 14px;
+  font: 400 14px/1 var(--font-sans);
+  color: var(--ink);
+  min-width: 0;
+}
+.r42-window-input input::placeholder { color: rgba(60, 58, 58, 0.4); }
+.r42-window-input input:disabled { opacity: 0.5; }
+.r42-window-input button {
+  background: var(--purple);
+  color: var(--cream);
+  border: none;
+  border-radius: var(--r-pill);
+  padding: 10px 18px;
+  font: 600 13px/1 var(--font-sans);
+  cursor: pointer;
+  transition: background 0.15s ease;
+  flex-shrink: 0;
+}
+.r42-window-input button:hover:not(:disabled) { background: var(--purple-700); }
+.r42-window-input button:disabled { opacity: 0.4; cursor: not-allowed; }

src/components/chat/prompts.js

@@ -0,0 +1,110 @@
+/**
+ * R42 — system prompts, greeting, and the propose_graph_delta tool spec.
+ * All user-facing strings live here so they can be localised in one place.
+ */
+
+export const BOT_NAME = 'R42';
+
+export const STRINGS = {
+  greeting: (name) =>
+    `Hoi ${name}, ik ben R42 — vraag iets over je weekonderwerp, of laat me uitleggen wat je in de quiz tegenkwam.`,
+  placeholder: `Vraag R42 iets…`,
+  send: 'Stuur',
+  status: 'online · antwoordt direct',
+  errorGeneric: 'Sorry, ik kon dat niet beantwoorden. Probeer het nog eens.',
+  errorNoKey: 'Er is geen API-sleutel ingesteld. Vraag een beheerder om hem toe te voegen in Admin → Settings.',
+  suggestionTitle: 'Ik hoorde iets nieuws — voeg toe aan de kennisgraaf?',
+  suggestionAccept: 'Ja, voeg toe',
+  suggestionReject: 'Nee, sla over',
+  suggestionAppliedAdmin: 'Toegevoegd aan de graaf.',
+  suggestionQueuedUser: 'Genoteerd — ik geef het door aan een beheerder.',
+  suggestionDismissed: 'Oké, niets gedaan.',
+  closeAria: 'Sluit chatvenster',
+  openAria: 'Open R42 chatbot',
+};
+
+export function buildSystemPrompt({ userName, isAdmin, kbContext }) {
+  return [
+    `Je bent R42, de chatbot-avatar van Respellion — een leerplatform voor microlearning, quizzen en kennisontwikkeling.`,
+    `Antwoord altijd in het Nederlands, kort en zakelijk-vriendelijk. Spreek de gebruiker aan met hun voornaam wanneer dat natuurlijk voelt (${userName}).`,
+    ``,
+    `JE TAKEN:`,
+    `1. Leg onderwerpen uit die in de kennisbasis staan.`,
+    `2. Help de gebruiker quizvragen begrijpen ná afloop (niet tijdens een actieve quiz).`,
+    `3. Verwijs bij twijfel terug naar het bronmateriaal of zeg eerlijk dat je het niet weet.`,
+    ``,
+    `JE KENNIS:`,
+    `Je kennis is beperkt tot de onderstaande Respellion-kennisgraaf. Als een vraag duidelijk buiten dit bereik valt, zeg dat dan eerlijk en stel voor dat de gebruiker de bron toevoegt via Admin → Sources.`,
+    ``,
+    kbContext,
+    ``,
+    `KENNISGRAAF VERFIJNEN:`,
+    `Wanneer de gebruiker iets noemt dat duidelijk een nieuw topic, nieuwe relatie, proces of rol is — en dat nog niet in de kennisgraaf staat — gebruik dan de tool "propose_graph_delta" om een voorstel te maken. Verzin niets: stel alleen iets voor als de gebruiker het concreet noemt. Stel maximaal 3 topics en 5 relaties per beurt voor.`,
+    ``,
+    `STIJL:`,
+    `- Houd antwoorden onder de 4 zinnen tenzij de gebruiker om uitleg vraagt.`,
+    `- Geen markdown-headers; gewone Nederlandse tekst.`,
+    `- Bij onzekerheid: "Ik weet het niet zeker — controleer dit in het handboek."`,
+    isAdmin
+      ? `\nDe gebruiker is beheerder; voorstellen die de tool genereert worden direct toegepast.`
+      : `\nDe gebruiker is geen beheerder; voorstellen worden in een goedkeuringswachtrij gezet.`,
+  ].join('\n');
+}
+
+export const PROPOSE_GRAPH_DELTA_TOOL = {
+  name: 'propose_graph_delta',
+  description:
+    'Stel toevoegingen aan de Respellion-kennisgraaf voor wanneer de gebruiker een topic, proces, rol of relatie noemt die nog niet bestaat. Gebruik dit alleen wanneer je iets nieuws en concreets hoort — niet voor algemene speculatie.',
+  input_schema: {
+    type: 'object',
+    properties: {
+      reason: {
+        type: 'string',
+        description: 'Korte uitleg (1 zin, NL) waarom dit voorstel relevant is.',
+      },
+      topics: {
+        type: 'array',
+        description: 'Maximaal 3 nieuwe topics.',
+        items: {
+          type: 'object',
+          properties: {
+            id: {
+              type: 'string',
+              description: 'kebab-case identifier, bv. "onboarding-buddy".',
+            },
+            label: {
+              type: 'string',
+              description: 'Mens-leesbare naam.',
+            },
+            type: {
+              type: 'string',
+              enum: ['concept', 'role', 'process'],
+            },
+            description: {
+              type: 'string',
+              description: '1–2 zinnen Nederlandstalige beschrijving.',
+            },
+          },
+          required: ['id', 'label', 'type', 'description'],
+        },
+      },
+      relations: {
+        type: 'array',
+        description: 'Maximaal 5 nieuwe relaties.',
+        items: {
+          type: 'object',
+          properties: {
+            source: { type: 'string', description: 'topic id' },
+            target: { type: 'string', description: 'topic id' },
+            type: {
+              type: 'string',
+              enum: ['related_to', 'depends_on', 'part_of', 'executed_by'],
+            },
+          },
+          required: ['source', 'target', 'type'],
+        },
+      },
+    },
+    required: ['reason'],
+  },
+};

src/components/chat/rag.js

@@ -0,0 +1,127 @@
+import * as db from '../../lib/db';
+
+/**
+ * Build a compact knowledge-base context string to inject into the system prompt.
+ * Reads topics + relations from PocketBase via db.js.
+ * Topic-level content is loaded only when a topic id/label appears in the user's message.
+ *
+ * Returns { context: string, topics: Array } so callers can reuse the fetched topics
+ * for validateDelta without a second round-trip.
+ */
+export async function buildKbContext(userMessage = '') {
+  const [topics, relations] = await Promise.all([
+    db.getTopics(),
+    db.getRelations(),
+  ]);
+
+  if (topics.length === 0) {
+    return {
+      context: 'KENNISGRAAF: (leeg — er zijn nog geen onderwerpen geëxtraheerd)',
+      topics: [],
+    };
+  }
+
+  const topicLines = topics.map(t => {
+    const desc = (t.description || '').replace(/\s+/g, ' ').trim().slice(0, 200);
+    return `- ${t.id} (${t.type || 'concept'}) "${t.label}": ${desc}`;
+  });
+
+  const relLines = relations.map(r => {
+    const src = typeof r.source === 'object' ? r.source.id : r.source;
+    const tgt = typeof r.target === 'object' ? r.target.id : r.target;
+    return `- ${src} --${r.type}--> ${tgt}`;
+  });
+
+  // Pull deep content for any topic explicitly mentioned in the user message.
+  const lowered = userMessage.toLowerCase();
+  const mentionedDeepContent = [];
+  for (const t of topics) {
+    const idHit = t.id && lowered.includes(t.id.toLowerCase());
+    const labelHit = t.label && lowered.includes(t.label.toLowerCase());
+    if (idHit || labelHit) {
+      const content = await db.getContent(t.id).catch(() => null);
+      if (content) {
+        let raw;
+        if (typeof content === 'string') raw = content;
+        else if (content.article) raw = content.article;
+        else raw = JSON.stringify(content);
+        const snippet = raw.replace(/\s+/g, ' ').trim().slice(0, 1200);
+        mentionedDeepContent.push(`### ${t.label}\n${snippet}`);
+      }
+    }
+  }
+
+  const context = [
+    `KENNISGRAAF — TOPICS:`,
+    topicLines.join('\n'),
+    ``,
+    `KENNISGRAAF — RELATIES:`,
+    relLines.length ? relLines.join('\n') : '(geen relaties)',
+    mentionedDeepContent.length
+      ? `\n\nDIEPERE INHOUD (voor genoemde topics):\n${mentionedDeepContent.join('\n\n')}`
+      : '',
+  ].join('\n');
+
+  return { context, topics };
+}
+
+/**
+ * Validate a delta proposal against the current topic list (already fetched).
+ * Drops:
+ *   - topics whose id already exists (by id or case-folded label)
+ *   - relations whose source/target isn't in the current graph + this delta
+ *   - self-referencing relations
+ * Caps to 3 topics + 5 relations.
+ *
+ * @param {object} delta - Raw input from the propose_graph_delta tool call
+ * @param {Array}  existingTopics - Topics already fetched from PocketBase
+ */
+export function validateDelta(delta, existingTopics = []) {
+  if (!delta || typeof delta !== 'object') return null;
+
+  const existingIds = new Set(existingTopics.map(t => t.id));
+  const existingLabels = new Set(existingTopics.map(t => (t.label || '').toLowerCase()));
+
+  const safeTopics = [];
+  for (const t of Array.isArray(delta.topics) ? delta.topics : []) {
+    if (!t || typeof t.id !== 'string' || typeof t.label !== 'string') continue;
+    if (existingIds.has(t.id)) continue;
+    if (existingLabels.has(t.label.toLowerCase())) continue;
+    if (!['concept', 'role', 'process'].includes(t.type)) continue;
+    safeTopics.push({
+      id: t.id.trim(),
+      label: t.label.trim(),
+      type: t.type,
+      description: (t.description || '').trim(),
+    });
+    existingIds.add(t.id);
+    existingLabels.add(t.label.toLowerCase());
+    if (safeTopics.length >= 3) break;
+  }
+
+  const knownAfter = new Set([...existingIds, ...safeTopics.map(t => t.id)]);
+  const safeRelations = [];
+  for (const r of Array.isArray(delta.relations) ? delta.relations : []) {
+    if (!r || typeof r.source !== 'string' || typeof r.target !== 'string') continue;
+    if (r.source === r.target) continue;
+    if (!knownAfter.has(r.source) || !knownAfter.has(r.target)) continue;
+    if (!['related_to', 'depends_on', 'part_of', 'executed_by'].includes(r.type)) continue;
+    safeRelations.push({ source: r.source, target: r.target, type: r.type });
+    if (safeRelations.length >= 5) break;
+  }
+
+  if (safeTopics.length === 0 && safeRelations.length === 0) return null;
+
+  return {
+    reason: typeof delta.reason === 'string' ? delta.reason : '',
+    topics: safeTopics,
+    relations: safeRelations,
+  };
+}
+
+/** Stable key for a delta (used to dedupe within a thread). */
+export function deltaKey(delta) {
+  const t = delta.topics.map(x => x.id).sort().join(',');
+  const r = delta.relations.map(x => `${x.source}-${x.type}->${x.target}`).sort().join(',');
+  return `t:${t}|r:${r}`;
+}

src/components/chat/useChat.js

@@ -0,0 +1,137 @@
+import { useCallback, useEffect, useRef, useState } from 'react';
+import { storage } from '../../lib/storage';
+import { anthropicApi } from '../../lib/api';
+import { buildKbContext, validateDelta, deltaKey } from './rag';
+import { buildSystemPrompt, PROPOSE_GRAPH_DELTA_TOOL, STRINGS } from './prompts';
+
+const MAX_HISTORY = 50;
+
+/**
+ * Conversation hook for R42.
+ * Owns the message list, persists to chat:thread:{userId}, calls Anthropic,
+ * and surfaces validated graph delta suggestions inline.
+ *
+ * Note: buildKbContext is async (reads PocketBase), so send() is fully async.
+ */
+export function useChat({ user, isAdmin }) {
+  const threadKey = user ? `chat:thread:${user.id}` : null;
+  const [messages, setMessages] = useState([]);
+  const [isThinking, setIsThinking] = useState(false);
+  const [errored, setErrored] = useState(false);
+  const seenDeltaKeys = useRef(new Set());
+
+  // Load persisted thread + seed greeting
+  useEffect(() => {
+    if (!user) return;
+    const stored = storage.get(threadKey, null);
+    if (stored && Array.isArray(stored) && stored.length) {
+      setMessages(stored);
+      for (const m of stored) {
+        if (m.suggestion?.key) seenDeltaKeys.current.add(m.suggestion.key);
+      }
+    } else {
+      setMessages([
+        {
+          id: `m_${Date.now()}`,
+          role: 'assistant',
+          content: STRINGS.greeting(user.name || 'daar'),
+          ts: Date.now(),
+        },
+      ]);
+    }
+  }, [user, threadKey]);
+
+  // Persist on change
+  useEffect(() => {
+    if (!threadKey) return;
+    const capped = messages.slice(-MAX_HISTORY);
+    storage.set(threadKey, capped);
+  }, [messages, threadKey]);
+
+  const updateMessage = useCallback((id, patch) => {
+    setMessages(prev => prev.map(m => (m.id === id ? { ...m, ...patch } : m)));
+  }, []);
+
+  const send = useCallback(async (text) => {
+    const trimmed = (text || '').trim();
+    if (!trimmed || !user) return;
+
+    const userMsg = {
+      id: `m_${Date.now()}_u`,
+      role: 'user',
+      content: trimmed,
+      ts: Date.now(),
+    };
+    const next = [...messages, userMsg];
+    setMessages(next);
+    setIsThinking(true);
+    setErrored(false);
+
+    try {
+      const { context: kbContext, topics: kbTopics } = await buildKbContext(trimmed);
+      const systemPrompt = buildSystemPrompt({
+        userName: user.name || 'daar',
+        isAdmin,
+        kbContext,
+      });
+
+      // Strip UI-only fields before sending to Anthropic
+      const apiMessages = next
+        .filter(m => m.role === 'user' || m.role === 'assistant')
+        .map(m => ({ role: m.role, content: m.content }));
+
+      const response = await anthropicApi.chat(systemPrompt, apiMessages, {
+        tools: [PROPOSE_GRAPH_DELTA_TOOL],
+      });
+
+      let textOut = '';
+      let suggestion = null;
+      for (const block of response.content || []) {
+        if (block.type === 'text') {
+          textOut += (textOut ? '\n' : '') + (block.text || '');
+        } else if (block.type === 'tool_use' && block.name === PROPOSE_GRAPH_DELTA_TOOL.name) {
+          const validated = validateDelta(block.input, kbTopics);
+          if (validated) {
+            const key = deltaKey(validated);
+            if (!seenDeltaKeys.current.has(key)) {
+              seenDeltaKeys.current.add(key);
+              suggestion = { ...validated, key, status: 'pending' };
+            }
+          }
+        }
+      }
+
+      const assistantMsg = {
+        id: `m_${Date.now()}_a`,
+        role: 'assistant',
+        content: textOut || (suggestion ? STRINGS.suggestionTitle : STRINGS.errorGeneric),
+        ts: Date.now(),
+        ...(suggestion ? { suggestion } : {}),
+      };
+      setMessages(prev => [...prev, assistantMsg]);
+    } catch (e) {
+      console.error('[R42] chat error', e);
+      setErrored(true);
+      const isKey = /api key/i.test(e?.message || '');
+      setMessages(prev => [
+        ...prev,
+        {
+          id: `m_${Date.now()}_e`,
+          role: 'error',
+          content: isKey ? STRINGS.errorNoKey : STRINGS.errorGeneric,
+          ts: Date.now(),
+        },
+      ]);
+    } finally {
+      setIsThinking(false);
+    }
+  }, [messages, user, isAdmin]);
+
+  return {
+    messages,
+    isThinking,
+    errored,
+    send,
+    updateMessage,
+  };
+}