Highlight upgrades in package shop

resources/js/admin/mobile/lib/packageShop.ts

@@ -0,0 +1,40 @@
+import type { Package } from '../../api';
+
+export function classifyPackageTier(price: number, activePrice: number | null): {
+  isUpgrade: boolean;
+  isDowngrade: boolean;
+} {
+  if (activePrice === null) {
+    return { isUpgrade: false, isDowngrade: false };
+  }
+
+  return {
+    isUpgrade: price > activePrice,
+    isDowngrade: price < activePrice,
+  };
+}
+
+export function selectRecommendedPackageId(
+  packages: Package[],
+  feature: string | null,
+  activePrice: number | null
+): number | null {
+  if (!feature) {
+    return null;
+  }
+
+  const candidates = packages.filter((pkg) => pkg.features?.[feature]);
+  if (candidates.length === 0) {
+    return null;
+  }
+
+  const upgradeCandidates =
+    activePrice === null
+      ? candidates
+      : candidates.filter((pkg) => pkg.price > activePrice);
+
+  const pool = upgradeCandidates.length ? upgradeCandidates : candidates;
+  const sorted = [...pool].sort((a, b) => a.price - b.price);
+
+  return sorted[0]?.id ?? null;
+}