fix(intelligence): Graph Reach — BFS gate, tab wiring, i18n flat (#2985)

app/src/components/intelligence/GraphReachPanel.test.tsx

@@ -0,0 +1,76 @@
+import { fireEvent, render, screen } from '@testing-library/react';
+import { describe, expect, it, vi } from 'vitest';
+
+import { computeGraphReach } from '../../lib/memory/graphReach';
+import type { GraphRelation } from '../../utils/tauriCommands/memory';
+import GraphReachPanel from './GraphReachPanel';
+
+function rel(subject: string, object: string): GraphRelation {
+  return {
+    namespace: 'n',
+    subject,
+    predicate: 'p',
+    object,
+    attrs: {},
+    updatedAt: 0,
+    evidenceCount: 1,
+    orderIndex: null,
+    documentIds: [],
+    chunkIds: [],
+  };
+}
+
+// Path A-B-C-D: diameter 3, radius 2, center {B,C}.
+const path = computeGraphReach([rel('A', 'B'), rel('B', 'C'), rel('C', 'D')]);
+
+describe('<GraphReachPanel />', () => {
+  it('renders the loading skeleton', () => {
+    render(<GraphReachPanel result={null} loading />);
+    expect(screen.getByTestId('graph-reach-loading')).toBeInTheDocument();
+  });
+
+  it('renders the empty state when there are no nodes', () => {
+    render(<GraphReachPanel result={computeGraphReach([])} />);
+    expect(screen.getByText('No knowledge graph yet.')).toBeInTheDocument();
+  });
+
+  it('renders an error with a working retry button', () => {
+    const onRetry = vi.fn();
+    render(<GraphReachPanel result={null} error="graph unavailable" onRetry={onRetry} />);
+    expect(screen.getByRole('alert').textContent).toMatch(/graph unavailable/);
+    fireEvent.click(screen.getByRole('button', { name: 'Retry' }));
+    expect(onRetry).toHaveBeenCalledTimes(1);
+  });
+
+  it('renders metric tiles, the component summary, and the ranked table', () => {
+    render(<GraphReachPanel result={path} />);
+    expect(screen.getByText('Entities')).toBeInTheDocument();
+    expect(screen.getByText('Diameter')).toBeInTheDocument();
+    expect(screen.getByText('Radius')).toBeInTheDocument();
+    expect(screen.getByText('Most central entities')).toBeInTheDocument();
+    // single component holding all four nodes -> singular caption variant.
+    expect(screen.getByText('1 component · 4 entities')).toBeInTheDocument();
+  });
+
+  it('badges the centers (eccentricity == radius) and not the periphery', () => {
+    render(<GraphReachPanel result={path} />);
+    // B and C are the two centers of the path; A and D are not.
+    expect(screen.getAllByText('center')).toHaveLength(2);
+  });
+
+  it('uses the plural caption when the graph has more than one component', () => {
+    // Path P-Q-R-S (giant, size 4) plus disjoint edge Y-Z (size 2).
+    const multi = computeGraphReach([rel('P', 'Q'), rel('Q', 'R'), rel('R', 'S'), rel('Y', 'Z')]);
+    render(<GraphReachPanel result={multi} />);
+    expect(screen.getByText('2 components · largest holds 4')).toBeInTheDocument();
+  });
+
+  it('uses the all-singular caption for a single-node component (self-loop-only)', () => {
+    // The only fact is "Alice→Alice": the engine keeps Alice as a singleton
+    // (size 1), and the caption renders the all-singular variant — never the
+    // ungrammatical "1 component · 1 entities".
+    const lonely = computeGraphReach([rel('Alice', 'Alice')]);
+    render(<GraphReachPanel result={lonely} />);
+    expect(screen.getByText('1 component · 1 entity')).toBeInTheDocument();
+  });
+});

app/src/components/intelligence/GraphReachPanel.tsx

@@ -0,0 +1,215 @@
+/**
+ * Graph Reach — presentational view. Pure: renders the reach summary tiles
+ * (entities / diameter / radius), the component summary, and a ranked table of
+ * the most-central entities. No data fetching, no clock, no randomness.
+ */
+import { useMemo } from 'react';
+
+import { useT } from '../../lib/i18n/I18nContext';
+import type { ReachResult } from '../../lib/memory/graphReach';
+
+const MAX_ROWS = 25;
+
+interface GraphReachPanelProps {
+  result: ReachResult | null;
+  loading?: boolean;
+  error?: string | null;
+  onRetry?: () => void;
+}
+
+const GraphReachPanel = ({ result, loading, error, onRetry }: GraphReachPanelProps) => {
+  const { t } = useT();
+
+  // Per-component diameter so each row's eccentricity bar is relative to its
+  // OWN component, not the giant component's diameter (which would let a node
+  // in a smaller-but-longer component render >100% width).
+  const componentDiameter = useMemo(() => {
+    const map = new Map<number, number>();
+    if (result) {
+      for (const c of result.components) map.set(c.id, c.diameter);
+    }
+    return map;
+  }, [result]);
+
+  const intro = (
+    <div
+      role="note"
+      className="rounded-lg border border-primary-200 dark:border-primary-500/30 bg-primary-50 dark:bg-primary-500/10 px-3 py-2 text-xs text-stone-700 dark:text-neutral-200">
+      <p className="font-medium mb-1">{t('graphReach.title')}</p>
+      <p>{t('graphReach.intro')}</p>
+    </div>
+  );
+
+  if (loading) {
+    return (
+      <div className="space-y-4">
+        {intro}
+        <div
+          className="space-y-3"
+          role="status"
+          aria-label={t('graphReach.loading')}
+          data-testid="graph-reach-loading">
+          <div className="grid gap-2 sm:grid-cols-3">
+            {[0, 1, 2].map(i => (
+              <div
+                key={i}
+                className="animate-pulse rounded-lg border border-stone-200 dark:border-neutral-800 bg-stone-50 dark:bg-neutral-800/60 h-16"
+              />
+            ))}
+          </div>
+          {[0, 1, 2, 3].map(i => (
+            <div
+              key={i}
+              className="animate-pulse rounded-lg border border-stone-200 dark:border-neutral-800 bg-stone-50 dark:bg-neutral-800/60 h-8"
+            />
+          ))}
+        </div>
+      </div>
+    );
+  }
+
+  if (error) {
+    return (
+      <div className="space-y-4">
+        {intro}
+        <div className="rounded-lg border border-coral-200 dark:border-coral-500/30 p-4 text-center">
+          <p role="alert" className="text-xs text-coral-700 dark:text-coral-300">
+            {t('graphReach.errorPrefix')} {error}
+          </p>
+          {onRetry && (
+            <button
+              type="button"
+              onClick={onRetry}
+              className="mt-2 rounded-lg bg-primary-500 px-3 py-1.5 text-xs font-semibold text-white hover:bg-primary-600">
+              {t('graphReach.retry')}
+            </button>
+          )}
+        </div>
+      </div>
+    );
+  }
+
+  if (!result || result.nodes.length === 0) {
+    return (
+      <div className="space-y-4">
+        {intro}
+        <div className="py-8 text-center">
+          <h3 className="text-sm font-semibold text-stone-700 dark:text-neutral-200">
+            {t('graphReach.empty')}
+          </h3>
+          <p className="mt-1 text-xs text-stone-500 dark:text-neutral-400">
+            {t('graphReach.emptyHint')}
+          </p>
+        </div>
+      </div>
+    );
+  }
+
+  const rows = result.nodes.slice(0, MAX_ROWS);
+
+  return (
+    <div className="space-y-4">
+      {intro}
+
+      {/* Metric tiles */}
+      <div className="grid gap-2 sm:grid-cols-3">
+        {[
+          { label: t('graphReach.metricEntities'), value: result.nodeCount },
+          { label: t('graphReach.metricDiameter'), value: result.diameter },
+          { label: t('graphReach.metricRadius'), value: result.radius },
+        ].map(tile => (
+          <div
+            key={tile.label}
+            className="rounded-lg border border-stone-200 dark:border-neutral-800 p-3">
+            <div className="text-[10px] uppercase tracking-wider text-stone-400 dark:text-neutral-500">
+              {tile.label}
+            </div>
+            <div className="text-lg font-semibold tabular-nums text-stone-900 dark:text-neutral-100">
+              {tile.value}
+            </div>
+          </div>
+        ))}
+      </div>
+      <p className="text-[11px] text-stone-500 dark:text-neutral-400">
+        {result.componentCount === 1
+          ? result.giantComponentSize === 1
+            ? t('graphReach.summaryCaptionOneAndOne')
+            : t('graphReach.summaryCaptionOne').replace(
+                '{giant}',
+                String(result.giantComponentSize)
+              )
+          : t('graphReach.summaryCaption')
+              .replace('{components}', String(result.componentCount))
+              .replace('{giant}', String(result.giantComponentSize))}
+      </p>
+
+      {/* Ranked most-central entities */}
+      <section aria-labelledby="graph-reach-heading" className="space-y-1">
+        <h3
+          id="graph-reach-heading"
+          className="text-xs font-semibold uppercase tracking-wider text-stone-500 dark:text-neutral-400">
+          {t('graphReach.rankedHeading')}
+        </h3>
+        <table
+          aria-labelledby="graph-reach-heading"
+          className="w-full text-left text-[11px] tabular-nums">
+          <thead className="text-stone-400 dark:text-neutral-500">
+            <tr>
+              <th scope="col" className="w-8 py-1 pr-2 font-medium">
+                {t('graphReach.colRank')}
+              </th>
+              <th scope="col" className="py-1 pr-2 font-medium">
+                {t('graphReach.colEntity')}
+              </th>
+              <th scope="col" className="w-1/3 py-1 pr-2 font-medium">
+                {t('graphReach.colEccentricity')}
+              </th>
+              <th scope="col" className="w-12 py-1 text-right font-medium">
+                {t('graphReach.colLinks')}
+              </th>
+            </tr>
+          </thead>
+          <tbody>
+            {rows.map((node, i) => {
+              const localDiameter = componentDiameter.get(node.componentId) ?? 0;
+              const barWidth = localDiameter === 0 ? 0 : (node.eccentricity / localDiameter) * 100;
+              return (
+                <tr key={node.id} className="border-t border-stone-100 dark:border-neutral-800/60">
+                  <td className="py-1 pr-2 text-stone-400 dark:text-neutral-500">{i + 1}</td>
+                  <td className="py-1 pr-2 text-stone-800 dark:text-neutral-100 break-words">
+                    {node.id}
+                    {node.isCenter && (
+                      <span
+                        title={t('graphReach.centerTitle')}
+                        className="ml-1.5 inline-flex items-center rounded px-1 py-0.5 text-[9px] font-semibold uppercase tracking-wider bg-primary-100 dark:bg-primary-500/20 text-primary-700 dark:text-primary-300">
+                        {t('graphReach.centerBadge')}
+                      </span>
+                    )}
+                  </td>
+                  <td className="py-1 pr-2">
+                    <div className="flex items-center gap-2">
+                      <div className="flex-1 h-2 rounded bg-stone-100 dark:bg-neutral-800 overflow-hidden">
+                        <div
+                          className="h-full bg-primary-400/70"
+                          style={{ width: `${barWidth}%` }}
+                        />
+                      </div>
+                      <span className="w-8 shrink-0 text-right text-stone-500 dark:text-neutral-400">
+                        {node.eccentricity}
+                      </span>
+                    </div>
+                  </td>
+                  <td className="py-1 text-right text-stone-500 dark:text-neutral-400">
+                    {node.degree}
+                  </td>
+                </tr>
+              );
+            })}
+          </tbody>
+        </table>
+      </section>
+    </div>
+  );
+};
+
+export default GraphReachPanel;

app/src/components/intelligence/GraphReachTab.test.tsx

@@ -0,0 +1,61 @@
+import { fireEvent, render, screen, waitFor } from '@testing-library/react';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+
+import { computeGraphReach } from '../../lib/memory/graphReach';
+import type { GraphRelation } from '../../utils/tauriCommands/memory';
+import GraphReachTab from './GraphReachTab';
+
+const mockLoadReach = vi.fn();
+const mockLoadNamespaces = vi.fn();
+
+vi.mock('../../services/api/graphReachApi', () => ({
+  loadReach: (...args: unknown[]) => mockLoadReach(...args),
+  loadNamespaces: (...args: unknown[]) => mockLoadNamespaces(...args),
+}));
+
+function rel(subject: string, object: string): GraphRelation {
+  return {
+    namespace: 'n',
+    subject,
+    predicate: 'p',
+    object,
+    attrs: {},
+    updatedAt: 0,
+    evidenceCount: 1,
+    orderIndex: null,
+    documentIds: [],
+    chunkIds: [],
+  };
+}
+
+const result = computeGraphReach([rel('A', 'B'), rel('B', 'C'), rel('C', 'D')]);
+
+describe('<GraphReachTab />', () => {
+  beforeEach(() => {
+    mockLoadReach.mockReset();
+    mockLoadNamespaces.mockReset();
+    mockLoadReach.mockResolvedValue(result);
+    mockLoadNamespaces.mockResolvedValue([]);
+  });
+
+  it('loads reach (all namespaces) on mount and renders the result', async () => {
+    render(<GraphReachTab />);
+    expect(mockLoadReach).toHaveBeenCalledWith(undefined);
+    await waitFor(() => expect(screen.getByText('Most central entities')).toBeInTheDocument());
+  });
+
+  it('shows the namespace selector and re-queries on change', async () => {
+    mockLoadNamespaces.mockResolvedValueOnce(['work', 'personal']);
+    render(<GraphReachTab />);
+    await waitFor(() => screen.getByRole('combobox'));
+    fireEvent.change(screen.getByRole('combobox'), { target: { value: 'work' } });
+    await waitFor(() => expect(mockLoadReach).toHaveBeenCalledWith('work'));
+  });
+
+  it('surfaces an error when the load fails', async () => {
+    mockLoadReach.mockReset();
+    mockLoadReach.mockRejectedValueOnce(new Error('graph unavailable'));
+    render(<GraphReachTab />);
+    await waitFor(() => expect(screen.getByRole('alert').textContent).toMatch(/graph unavailable/));
+  });
+});