feat: validate PDF options with TDD tests

src/__tests__/convert.test.ts

@@ -182,3 +182,66 @@ describe("POST /v1/convert/url", () => {
     expect(res.headers["content-type"]).toMatch(/application\/pdf/);
   });
 });
+
+describe("PDF option validation (all endpoints)", () => {
+  const endpoints = [
+    { path: "/v1/convert/html", body: { html: "<h1>Hi</h1>" } },
+    { path: "/v1/convert/markdown", body: { markdown: "# Hi" } },
+  ];
+
+  for (const { path, body } of endpoints) {
+    it(`${path} returns 400 for invalid scale`, async () => {
+      const res = await request(app)
+        .post(path)
+        .set("content-type", "application/json")
+        .send({ ...body, scale: 5 });
+      expect(res.status).toBe(400);
+      expect(res.body.error).toContain("scale");
+    });
+
+    it(`${path} returns 400 for invalid format`, async () => {
+      const res = await request(app)
+        .post(path)
+        .set("content-type", "application/json")
+        .send({ ...body, format: "B5" });
+      expect(res.status).toBe(400);
+      expect(res.body.error).toContain("format");
+    });
+
+    it(`${path} returns 400 for non-boolean landscape`, async () => {
+      const res = await request(app)
+        .post(path)
+        .set("content-type", "application/json")
+        .send({ ...body, landscape: "yes" });
+      expect(res.status).toBe(400);
+      expect(res.body.error).toContain("landscape");
+    });
+
+    it(`${path} returns 400 for invalid pageRanges`, async () => {
+      const res = await request(app)
+        .post(path)
+        .set("content-type", "application/json")
+        .send({ ...body, pageRanges: "abc" });
+      expect(res.status).toBe(400);
+      expect(res.body.error).toContain("pageRanges");
+    });
+
+    it(`${path} returns 400 for invalid margin`, async () => {
+      const res = await request(app)
+        .post(path)
+        .set("content-type", "application/json")
+        .send({ ...body, margin: "1cm" });
+      expect(res.status).toBe(400);
+      expect(res.body.error).toContain("margin");
+    });
+  }
+
+  it("/v1/convert/url returns 400 for invalid scale", async () => {
+    const res = await request(app)
+      .post("/v1/convert/url")
+      .set("content-type", "application/json")
+      .send({ url: "https://example.com", scale: 5 });
+    expect(res.status).toBe(400);
+    expect(res.body.error).toContain("scale");
+  });
+});