From 8639478a113448a8ce431449c3b457f7ae7d83c2 Mon Sep 17 00:00:00 2001
From: Matthias Meister <meister.matthias86@gmail.com>
Date: Fri, 3 Apr 2026 19:20:28 +0200
Subject: [PATCH] refactor(config): unify tier credit constants across frontend
 and backend

---
 convex/credits.ts     | 15 ++++++++-------
 lib/polar-products.ts | 15 +++++++--------
 lib/tier-credits.ts   | 32 ++++++++++++++++++++++++++++++++
 3 files changed, 47 insertions(+), 15 deletions(-)
 create mode 100644 lib/tier-credits.ts

diff --git a/convex/credits.ts b/convex/credits.ts
index 0388636..d02c510 100644
--- a/convex/credits.ts
+++ b/convex/credits.ts
@@ -2,6 +2,7 @@ import { query, mutation, internalMutation } from "./_generated/server";
 import { v, ConvexError } from "convex/values";
 import { optionalAuth, requireAuth } from "./helpers";
 import { internal } from "./_generated/api";
+import { MONTHLY_TIER_CREDITS, normalizeBillingTier } from "../lib/tier-credits";
 
 // ============================================================================
 // Tier-Konfiguration
@@ -9,35 +10,35 @@ import { internal } from "./_generated/api";
 
 export const TIER_CONFIG = {
   free: {
-    monthlyCredits: 50,
+    monthlyCredits: MONTHLY_TIER_CREDITS.free,
     dailyGenerationCap: 10,
     concurrencyLimit: 1,
     premiumModels: false,
     topUpLimit: 50000,
   },
   starter: {
-    monthlyCredits: 400,
+    monthlyCredits: MONTHLY_TIER_CREDITS.starter,
     dailyGenerationCap: 50,
     concurrencyLimit: 2,
     premiumModels: true,
     topUpLimit: 2000,             // €20 pro Monat
   },
   pro: {
-    monthlyCredits: 3300,
+    monthlyCredits: MONTHLY_TIER_CREDITS.pro,
     dailyGenerationCap: 200,
     concurrencyLimit: 2,
     premiumModels: true,
     topUpLimit: 10000,            // €100 pro Monat
   },
   max: {
-    monthlyCredits: 6700,
+    monthlyCredits: MONTHLY_TIER_CREDITS.max,
     dailyGenerationCap: 500,
     concurrencyLimit: 2,
     premiumModels: true,
     topUpLimit: 50000,
   },
   business: {
-    monthlyCredits: 6700,
+    monthlyCredits: MONTHLY_TIER_CREDITS.business,
     dailyGenerationCap: 500,
     concurrencyLimit: 2,
     premiumModels: true,
@@ -443,7 +444,7 @@ export const reserve = mutation({
       .withIndex("by_user", (q) => q.eq("userId", user.userId))
       .order("desc")
       .first();
-    const tier = (subscription?.tier ?? "free") as Tier;
+    const tier = normalizeBillingTier(subscription?.tier);
     const config = TIER_CONFIG[tier];
 
     // Daily Cap prüfen
@@ -825,7 +826,7 @@ export const checkAbuseLimits = internalMutation({
       .withIndex("by_user", (q) => q.eq("userId", user.userId))
       .order("desc")
       .first();
-    const tier = (subscription?.tier ?? "free") as Tier;
+    const tier = normalizeBillingTier(subscription?.tier);
     const config = TIER_CONFIG[tier];
 
     const today = new Date().toISOString().split("T")[0];
diff --git a/lib/polar-products.ts b/lib/polar-products.ts
index 38ecf01..a3ef1d8 100644
--- a/lib/polar-products.ts
+++ b/lib/polar-products.ts
@@ -1,3 +1,8 @@
+import {
+  PUBLIC_TIER_MONTHLY_CREDITS,
+  normalizePublicTier,
+} from "./tier-credits";
+
 export const SUBSCRIPTION_PRODUCTS = {
   starter: {
     polarProductId: "81b6de07-cd41-430f-bd54-f0e7072deec6",
@@ -47,15 +52,9 @@ export const TOPUP_PRODUCTS = [
 ] as const;
 
 export const TIER_MONTHLY_CREDITS = {
-  free: 50,
-  starter: 400,
-  pro: 3300,
-  max: 6700,
+  ...PUBLIC_TIER_MONTHLY_CREDITS,
 } as const;
 
 export function normalizeTier(tier: string | undefined | null): keyof typeof TIER_MONTHLY_CREDITS {
-  if (!tier || tier === "free") return "free";
-  if (tier === "starter" || tier === "pro" || tier === "max") return tier;
-  if (tier === "business") return "max";
-  return "free";
+  return normalizePublicTier(tier);
 }
diff --git a/lib/tier-credits.ts b/lib/tier-credits.ts
new file mode 100644
index 0000000..c6cfc68
--- /dev/null
+++ b/lib/tier-credits.ts
@@ -0,0 +1,32 @@
+export const MONTHLY_TIER_CREDITS = {
+  free: 50,
+  starter: 400,
+  pro: 3300,
+  max: 6700,
+  business: 6700,
+} as const;
+
+export type BillingTier = keyof typeof MONTHLY_TIER_CREDITS;
+
+export const PUBLIC_TIER_MONTHLY_CREDITS = {
+  free: MONTHLY_TIER_CREDITS.free,
+  starter: MONTHLY_TIER_CREDITS.starter,
+  pro: MONTHLY_TIER_CREDITS.pro,
+  max: MONTHLY_TIER_CREDITS.max,
+} as const;
+
+export type PublicTier = keyof typeof PUBLIC_TIER_MONTHLY_CREDITS;
+
+export function normalizeBillingTier(tier: string | undefined | null): BillingTier {
+  if (!tier || tier === "free") return "free";
+  if (tier === "starter" || tier === "pro" || tier === "max" || tier === "business") {
+    return tier;
+  }
+  return "free";
+}
+
+export function normalizePublicTier(tier: string | undefined | null): PublicTier {
+  const normalizedTier = normalizeBillingTier(tier);
+  if (normalizedTier === "business") return "max";
+  return normalizedTier;
+}