Implement public audit pages

lib/audits/slugs.ts

@@ -0,0 +1,40 @@
+const MAX_PUBLIC_AUDIT_SLUG_LENGTH = 120;
+
+const transliterations: Record<string, string> = {
+  ä: "ae",
+  ö: "oe",
+  ü: "ue",
+  ß: "ss",
+  æ: "ae",
+  ø: "oe",
+  å: "a",
+};
+
+export const toPublicAuditSlug = (companyName: string, domain: string) => {
+  const input = `${companyName} ${domain}`.trim().toLowerCase();
+  const normalized = input
+    .replace(/[äöüßæøå]/g, (character) => transliterations[character] ?? character)
+    .normalize("NFKD")
+    .replace(/[\u0300-\u036f]/g, "")
+    .replace(/[^a-z0-9]+/g, "-")
+    .replace(/^-+|-+$/g, "")
+    .replace(/-{2,}/g, "-")
+    .slice(0, MAX_PUBLIC_AUDIT_SLUG_LENGTH)
+    .replace(/-+$/g, "");
+
+  return normalized.length > 0 ? normalized : "audit";
+};
+
+export const parsePublicAuditSlug = (slug: string) => {
+  const normalized = slug.trim().toLowerCase();
+
+  if (
+    normalized.length === 0 ||
+    normalized.length > MAX_PUBLIC_AUDIT_SLUG_LENGTH ||
+    !/^[a-z0-9]+(?:-[a-z0-9]+)*$/.test(normalized)
+  ) {
+    return null;
+  }
+
+  return normalized;
+};