// Server-only: this module pulls in Prisma. Do not import from client
// components — `@/lib/reviews` (constants/types) is the safe surface.

import { prisma } from "@/lib/prisma";

import type { CarbetReview, CarbetReviewStats } from "@/lib/reviews";

// Aggregate stats used on cards and detail pages. Returns null average when
// there are no reviews so the caller can render a neutral "no reviews yet"
// state rather than a misleading 0.0.
export async function getCarbetReviewStats(
  carbetId: string,
): Promise<CarbetReviewStats> {
  const agg = await prisma.review.aggregate({
    where: { carbetId },
    _count: { _all: true },
    _avg: { rating: true },
  });

  const count = agg._count._all;
  const avg = agg._avg.rating;

  return {
    count,
    averageRating: count > 0 && avg !== null ? Number(avg) : null,
  };
}

export async function getCarbetReviewStatsMany(
  carbetIds: string[],
): Promise<Map<string, CarbetReviewStats>> {
  if (carbetIds.length === 0) {
    return new Map();
  }

  const rows = await prisma.review.groupBy({
    by: ["carbetId"],
    where: { carbetId: { in: carbetIds } },
    _count: { _all: true },
    _avg: { rating: true },
  });

  const map = new Map<string, CarbetReviewStats>();
  for (const id of carbetIds) {
    map.set(id, { count: 0, averageRating: null });
  }
  for (const row of rows) {
    const avg = row._avg.rating;
    map.set(row.carbetId, {
      count: row._count._all,
      averageRating: avg !== null ? Number(avg) : null,
    });
  }
  return map;
}

export async function listCarbetReviews(
  carbetId: string,
  limit = 20,
): Promise<CarbetReview[]> {
  const reviews = await prisma.review.findMany({
    where: { carbetId },
    orderBy: { createdAt: "desc" },
    take: limit,
    select: {
      id: true,
      rating: true,
      comment: true,
      hostResponse: true,
      hostRespondedAt: true,
      createdAt: true,
      author: { select: { firstName: true } },
      booking: { select: { startDate: true, endDate: true } },
    },
  });

  return reviews.map((review) => ({
    id: review.id,
    rating: review.rating,
    comment: review.comment,
    hostResponse: review.hostResponse,
    hostRespondedAt: review.hostRespondedAt?.toISOString() ?? null,
    createdAt: review.createdAt.toISOString(),
    authorFirstName: review.author.firstName,
    stayStartDate: review.booking.startDate.toISOString(),
    stayEndDate: review.booking.endDate.toISOString(),
  }));
}