fix(web): validate ontology pagination (#138)

apps/logicsrc-web/src/lib/pagination.test.ts

@@ -0,0 +1,17 @@
+import { describe, test } from "node:test";
+import assert from "node:assert/strict";
+import { parseBoundedIntegerParam } from "./pagination.ts";
+
+describe("pagination parameters", () => {
+  test("uses the fallback for negative, fractional, and malformed values", () => {
+    for (const value of [null, "-1", "1.5", "invalid", "9007199254740992"]) {
+      assert.equal(parseBoundedIntegerParam(value, 50, 1, 200), 50);
+    }
+  });
+
+  test("accepts valid values and caps the upper bound", () => {
+    assert.equal(parseBoundedIntegerParam(" 1 ", 50, 1, 200), 1);
+    assert.equal(parseBoundedIntegerParam("500", 50, 1, 200), 200);
+    assert.equal(parseBoundedIntegerParam("0", 0, 0, Number.MAX_SAFE_INTEGER), 0);
+  });
+});

apps/logicsrc-web/src/lib/pagination.ts

@@ -0,0 +1,13 @@
+export function parseBoundedIntegerParam(
+  value: string | null,
+  fallback: number,
+  minimum: number,
+  maximum: number
+): number {
+  const text = value?.trim() ?? "";
+  if (!/^\d+$/.test(text)) return fallback;
+
+  const parsed = Number(text);
+  if (!Number.isSafeInteger(parsed) || parsed < minimum) return fallback;
+  return Math.min(parsed, maximum);
+}