add payment, trust badge, handle race condition, fix booking schema

server/services/trust.service.ts

@@ -0,0 +1,39 @@
+import { prisma } from "@/lib/prisma";
+import { TRIP_LEADER_MIN_TRIPS } from "@/lib/trust";
+
+export type OrganizerTrust = {
+  isVerified: boolean;
+  tripsCreated: number;
+  avgRating: number | null;
+  reviewCount: number;
+  isTripLeader: boolean;
+};
+
+export const trustService = {
+  async getOrganizerTrust(organizerId: string): Promise<OrganizerTrust> {
+    const [user, tripsCreated, reviewAgg] = await Promise.all([
+      prisma.user.findUnique({
+        where: { id: organizerId },
+        select: { isVerified: true },
+      }),
+      prisma.trip.count({ where: { organizerId } }),
+      prisma.tripReview.aggregate({
+        where: {
+          trip: { organizerId },
+        },
+        _avg: { rating: true },
+        _count: { _all: true },
+      }),
+    ]);
+
+    const avg = reviewAgg._avg.rating;
+    return {
+      isVerified: user?.isVerified ?? false,
+      tripsCreated,
+      avgRating:
+        avg != null ? Math.round(Number(avg) * 10) / 10 : null,
+      reviewCount: reviewAgg._count._all,
+      isTripLeader: tripsCreated >= TRIP_LEADER_MIN_TRIPS,
+    };
+  },
+};