import { NextRequest, NextResponse } from "next/server";
import { prisma } from "@/lib/prisma";
import { requireAuth } from "@/lib/auth";

// POST /api/souq/reviews — create a review
export async function POST(request: NextRequest) {
  try {
    const auth = await requireAuth(request);
    if (!auth) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    const { listingId, orderId, rating, title, text } = await request.json();

    // ── Validate fields ──
    if (!listingId || !orderId) {
      return NextResponse.json(
        { error: "Missing required fields: listingId, orderId" },
        { status: 400 }
      );
    }

    if (!rating || typeof rating !== "number" || rating < 1 || rating > 5 || !Number.isInteger(rating)) {
      return NextResponse.json(
        { error: "Rating must be an integer between 1 and 5" },
        { status: 400 }
      );
    }

    // ── Ensure the order exists and belongs to this user ──
    const order = await prisma.purchase.findUnique({
      where: { id: orderId },
      include: { listing: { select: { id: true, sellerId: true } } },
    });

    if (!order) {
      return NextResponse.json({ error: "Order not found" }, { status: 404 });
    }

    if (order.buyerId !== auth.userId) {
      return NextResponse.json(
        { error: "Only the buyer can review this order" },
        { status: 403 }
      );
    }

    if (order.status !== "completed") {
      return NextResponse.json(
        { error: "Can only review completed orders" },
        { status: 400 }
      );
    }

    if (order.listingId !== listingId) {
      return NextResponse.json(
        { error: "Listing does not match this order" },
        { status: 400 }
      );
    }

    // ── Check if user already reviewed this purchase ──
    const existing = await prisma.review.findFirst({
      where: { purchaseId: orderId, reviewerId: auth.userId },
    });

    if (existing) {
      return NextResponse.json(
        { error: "You have already reviewed this order" },
        { status: 409 }
      );
    }

    // ── Create the review and update listing stats in a transaction ──
    const [review] = await prisma.$transaction(async (tx) => {
      const created = await tx.review.create({
        data: {
          listingId,
          purchaseId: orderId,
          reviewerId: auth.userId,
          sellerId: order.listing.sellerId,
          rating,
          title: title || null,
          text: text ?? "",
        },
      });

      // Recalculate listing average rating and count
      const agg = await tx.review.aggregate({
        where: { listingId },
        _avg: { rating: true },
        _count: { rating: true },
      });

      await tx.listing.update({
        where: { id: listingId },
        data: {
          rating: agg._avg.rating ?? 0,
          reviewCount: agg._count.rating,
        },
      });

      return [created];
    });

    return NextResponse.json({ review }, { status: 201 });
  } catch (error) {
    console.error("POST /api/souq/reviews error:", error);
    return NextResponse.json(
      { error: "Internal server error" },
      { status: 500 }
    );
  }
}