Refactor for centralized regex check module and regex syntax. Added comments.

src/lib/metaLinkCheck.ts

@@ -0,0 +1,22 @@
+// Global regex used to detect all meta services.
+const metaRegex =
+  /(facebook\.com|meta\.com|instagram\.com|threads\.net|whatsapp\.com)/gi;
+
+/**
+ * This function will check if a url matches Meta services links using regex.
+ *
+ * @param linkUrl representing a suspected blacklisted url
+ * @returns flag
+ */
+const metaLinkCheck = (linkUrl: string): boolean => {
+  let flag = false;
+
+  if (linkUrl.match(metaRegex)) {
+    flag = true;
+  }
+
+  return flag;
+};
+
+export { metaRegex };
+export default metaLinkCheck;

src/lib/twitterLinkCheck.ts

@@ -0,0 +1,21 @@
+// Global regex used to detect Twitter and X links.
+const twitterRegex = /(x\.com|twitter\.com)/gi;
+
+/**
+ * This function will check if a url matches Twitter/X services links using regex.
+ *
+ * @param linkUrl representing a suspected blacklisted url
+ * @return flag
+ */
+const twitterLinkCheck = (linkUrl: string): boolean => {
+  let flag = false;
+
+  if (linkUrl.match(twitterRegex)) {
+    flag = true;
+  }
+
+  return flag;
+};
+
+export { twitterRegex };
+export default twitterLinkCheck;