optimize shouldSetCookie

Author: steven-tey

packages/script/src/base.js

@@ -122,23 +122,27 @@
   function init() {
     const params = new URLSearchParams(location.search);
 
-    const shouldSetCookie = () => {
+    const shouldSetCookie = (clickId) => {
+      const existingClickId = cookieManager.get(DUB_ID_VAR);
+      // only set cookie if there's no existing click id
+      // or if the attribution model is last-click and the new click id is different from the existing one
       return (
-        !cookieManager.get(DUB_ID_VAR) || ATTRIBUTION_MODEL !== 'first-click'
+        !existingClickId ||
+        (ATTRIBUTION_MODEL === 'last-click' && clickId !== existingClickId)
       );
     };
 
     // Direct click ID in URL
     const clickId = params.get(DUB_ID_VAR);
-    if (clickId && shouldSetCookie()) {
+    if (clickId && shouldSetCookie(clickId)) {
       cookieManager.set(DUB_ID_VAR, clickId);
       setPartnerData(clickId);
       return;
     }
 
     // Track via query param
     if (QUERY_PARAM_VALUE && SHORT_DOMAIN) {
-      if (shouldSetCookie()) {
+      if (shouldSetCookie(clickId)) {
         trackClick(QUERY_PARAM_VALUE);
       }
     }