feat: add lang filter to /api/sets

CLAUDE.md

@@ -10,6 +10,7 @@ Casecomp — Pokemon TCG card research tool. API at api.casecomp.xyz (Cloud Run
 - **No Co-Authored-By lines** in commits. No "Generated with Claude Code" in PR descriptions or any public text.
 - **Branch flow:** push to dev or main → CI runs → deploy on main push.
 - **Commits:** concise message, no attribution trailers.
+- **Before each commit:** consider whether new unit, API, or smoke tests are needed for the change. Add them in the same commit.
 - **PR template:** .github/PULL_REQUEST_TEMPLATE.md
 
 ## Code style

api.js

@@ -890,10 +890,12 @@ app.get("/api/autocomplete", requireCardDb, (req, res) => {
 
 // GET /api/sets
 app.get("/api/sets", requireCardDb, (req, res) => {
-  const sets = getAllSets();
-  const era = req.query.era;
-  const filtered = era ? sets.filter(s => s.era === era) : sets;
-  res.json({ sets: filtered, count: filtered.length });
+  let sets = getAllSets();
+  if (req.query.era) sets = sets.filter(s => s.era === req.query.era);
+  const lang = req.query.lang;
+  if (lang === "en") sets = sets.filter(s => s.lang === "en" || s.lang === "both");
+  else if (lang === "jp") sets = sets.filter(s => s.lang === "jp" || s.lang === "both");
+  res.json({ sets, count: sets.length });
 });
 
 // GET /api/sets/:setCode
@@ -2465,13 +2467,3 @@ process.on("uncaughtException", (err) => {
   logError("uncaughtException", err.message, err.stack?.split("\n")[1]?.trim());
   setTimeout(() => process.exit(1), 1000);
 });
-
-process.on("unhandledRejection", (reason) => {
-  const msg = reason instanceof Error ? reason.message : String(reason);
-  logError("unhandledRejection", msg, reason instanceof Error ? reason.stack?.split("\n")[1]?.trim() : "");
-});
-
-process.on("uncaughtException", (err) => {
-  logError("uncaughtException", err.message, err.stack?.split("\n")[1]?.trim());
-  setTimeout(() => process.exit(1), 1000);
-});

lib/cards/card-database.js

@@ -262,6 +262,7 @@ function buildIndexFromApi(enCards, jaCards, rarityMap = new Map()) {
       setCode,
       imageUrl: buildImageUrl(card.image),
       rarity: rarityMap.get(card.id) || null,
+      lang: "en",
     });
   }
 
@@ -277,6 +278,7 @@ function buildIndexFromApi(enCards, jaCards, rarityMap = new Map()) {
       setCode,
       imageUrl: buildImageUrl(card.image),
       rarity: rarityMap.get(card.id) || null,
+      lang: "jp",
     });
   }
 
@@ -428,10 +430,12 @@ export function getAllSets() {
     if (!card.setCode) continue;
     const code = card.setCode.toLowerCase();
     if (!setMap.has(code)) {
-      setMap.set(code, { count: 0, bestImage: null, bestNum: 0 });
+      setMap.set(code, { count: 0, enCount: 0, jpCount: 0, bestImage: null, bestNum: 0 });
     }
     const entry = setMap.get(code);
     entry.count++;
+    if (card.lang === "en") entry.enCount++;
+    else if (card.lang === "jp") entry.jpCount++;
     if (card.imageUrl) {
       const num = parseInt(card.localId, 10) || 0;
       if (num > entry.bestNum) {
@@ -446,11 +450,13 @@ export function getAllSets() {
     const meta = tcgdexSetMeta.get(code);
     const officialCards = meta?.officialCards ?? null;
     const metaTotal = meta?.totalCards ?? null;
+    const lang = data.enCount > 0 && data.jpCount > 0 ? "both" : data.enCount > 0 ? "en" : "jp";
     sets.push({
       setCode: code,
       name: resolveSetName(code),
       era: deriveEra(code),
       totalCards: data.count,
+      lang,
       logo: meta?.logo || null,
       officialCards,
       secretCards: officialCards != null && metaTotal != null ? metaTotal - officialCards : null,

test/api-test.js

@@ -922,6 +922,31 @@ async function run() {
     assert(res.status === 404, `expected 404, got ${res.status}`);
   });
 
+  await test("GET /api/sets includes lang field on each set", async () => {
+    const { body } = await jsonNoAuth("/api/sets");
+    for (const s of body.sets) {
+      assert(["en", "jp", "both"].includes(s.lang), `unexpected lang ${s.lang} on set ${s.setCode}`);
+    }
+  });
+
+  await test("GET /api/sets?lang=en filters to EN sets", async () => {
+    const { body: all } = await jsonNoAuth("/api/sets");
+    const { body: en } = await jsonNoAuth("/api/sets?lang=en");
+    assert(en.count <= all.count, "en count should be <= total");
+    for (const s of en.sets) {
+      assert(s.lang === "en" || s.lang === "both", `expected en/both, got ${s.lang}`);
+    }
+  });
+
+  await test("GET /api/sets?lang=jp filters to JP sets", async () => {
+    const { body: all } = await jsonNoAuth("/api/sets");
+    const { body: jp } = await jsonNoAuth("/api/sets?lang=jp");
+    assert(jp.count <= all.count, "jp count should be <= total");
+    for (const s of jp.sets) {
+      assert(s.lang === "jp" || s.lang === "both", `expected jp/both, got ${s.lang}`);
+    }
+  });
+
   // ── Price trend ──
 
   console.log("\n\x1b[1m=== price trend ===\x1b[0m");

test/unit-test.js

@@ -1070,6 +1070,13 @@ test("getAllSets: returns empty array when no cards loaded", () => {
   eq(Array.isArray(sets), true);
 });
 
+test("getAllSets: lang field is en, jp, or both", () => {
+  const sets = getAllSets();
+  for (const s of sets) {
+    eq(["en", "jp", "both", undefined].includes(s.lang), true);
+  }
+});
+
 test("getSetWithCards: returns null for nonexistent set", () => {
   eq(getSetWithCards("zzz999"), null);
 });