Persist stats exclusions in DB and fix word metrics filtering (#60)

stats/src/lib/api-client.test.ts

@@ -172,6 +172,50 @@ test('getSessionEvents can request only specific event types', async () => {
   }
 });
 
+test('getExcludedWords requests database-backed exclusions', async () => {
+  const originalFetch = globalThis.fetch;
+  let seenUrl = '';
+  globalThis.fetch = (async (input: RequestInfo | URL) => {
+    seenUrl = String(input);
+    return new Response(JSON.stringify([{ headword: '猫', word: '猫', reading: 'ねこ' }]), {
+      status: 200,
+      headers: { 'Content-Type': 'application/json' },
+    });
+  }) as typeof globalThis.fetch;
+
+  try {
+    const words = await apiClient.getExcludedWords();
+    assert.equal(seenUrl, `${BASE_URL}/api/stats/excluded-words`);
+    assert.deepEqual(words, [{ headword: '猫', word: '猫', reading: 'ねこ' }]);
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+});
+
+test('setExcludedWords replaces database-backed exclusions', async () => {
+  const originalFetch = globalThis.fetch;
+  let seenUrl = '';
+  let seenMethod = '';
+  let seenBody = '';
+  globalThis.fetch = (async (input: RequestInfo | URL, init?: RequestInit) => {
+    seenUrl = String(input);
+    seenMethod = init?.method ?? 'GET';
+    seenBody = String(init?.body ?? '');
+    return new Response(null, { status: 200 });
+  }) as typeof globalThis.fetch;
+
+  try {
+    await apiClient.setExcludedWords([{ headword: '猫', word: '猫', reading: 'ねこ' }]);
+    assert.equal(seenUrl, `${BASE_URL}/api/stats/excluded-words`);
+    assert.equal(seenMethod, 'PUT');
+    assert.deepEqual(JSON.parse(seenBody), {
+      words: [{ headword: '猫', word: '猫', reading: 'ねこ' }],
+    });
+  } finally {
+    globalThis.fetch = originalFetch;
+  }
+});
+
 test('getSessionTimeline requests full session history when limit is omitted', async () => {
   const originalFetch = globalThis.fetch;
   let seenUrl = '';

stats/src/lib/api-client.ts

@@ -22,6 +22,7 @@ import type {
   KanjiDetailData,
   EpisodeDetailData,
   StatsAnkiNoteInfo,
+  StatsExcludedWord,
 } from '../types/stats';
 
 type StatsLocationLike = Pick<Location, 'protocol' | 'origin' | 'search'>;
@@ -85,11 +86,19 @@ export const apiClient = {
     return fetchJson<SessionEvent[]>(`/api/stats/sessions/${id}/events?${params.toString()}`);
   },
   getSessionKnownWordsTimeline: (id: number) =>
-    fetchJson<Array<{ linesSeen: number; knownWordsSeen: number }>>(
+    fetchJson<Array<{ linesSeen: number; knownWordsSeen: number; totalWordsSeen: number }>>(
       `/api/stats/sessions/${id}/known-words-timeline`,
     ),
   getVocabulary: (limit = 100) =>
     fetchJson<VocabularyEntry[]>(`/api/stats/vocabulary?limit=${limit}`),
+  getExcludedWords: () => fetchJson<StatsExcludedWord[]>('/api/stats/excluded-words'),
+  setExcludedWords: async (words: StatsExcludedWord[]): Promise<void> => {
+    await fetchResponse('/api/stats/excluded-words', {
+      method: 'PUT',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ words }),
+    });
+  },
   getWordOccurrences: (headword: string, word: string, reading: string, limit = 50, offset = 0) =>
     fetchJson<VocabularyOccurrenceEntry[]>(
       `/api/stats/vocabulary/occurrences?headword=${encodeURIComponent(headword)}&word=${encodeURIComponent(word)}&reading=${encodeURIComponent(reading)}&limit=${limit}&offset=${offset}`,

stats/src/lib/session-detail.test.tsx

@@ -1,7 +1,11 @@
 import assert from 'node:assert/strict';
 import test from 'node:test';
 import { renderToStaticMarkup } from 'react-dom/server';
-import { SessionDetail, getKnownPctAxisMax } from '../components/sessions/SessionDetail';
+import {
+  SessionDetail,
+  buildKnownWordsRatioChartData,
+  getKnownPctAxisMax,
+} from '../components/sessions/SessionDetail';
 import { buildSessionChartEvents } from './session-events';
 import { EventType } from '../types/stats';
 
@@ -69,3 +73,21 @@ test('getKnownPctAxisMax adds headroom above the highest known percentage', () =
 test('getKnownPctAxisMax caps the chart top at 100%', () => {
   assert.equal(getKnownPctAxisMax([97.1, 98.6]), 100);
 });
+
+test('buildKnownWordsRatioChartData uses filtered known-word timeline totals', () => {
+  const chartData = buildKnownWordsRatioChartData(
+    [
+      { sampleMs: 1_000, linesSeen: 1, tokensSeen: 10 },
+      { sampleMs: 2_000, linesSeen: 2, tokensSeen: 20 },
+    ],
+    new Map([
+      [1, { knownWordsSeen: 2, totalWordsSeen: 3 }],
+      [2, { knownWordsSeen: 3, totalWordsSeen: 4 }],
+    ]),
+  );
+
+  assert.deepEqual(chartData, [
+    { tsMs: 1_000, knownWords: 2, unknownWords: 1, totalWords: 3 },
+    { tsMs: 2_000, knownWords: 3, unknownWords: 1, totalWords: 4 },
+  ]);
+});