import { getPb } from "../lib/pb";
import OrderClient from "./OrderClient";

export const dynamic = "force-dynamic";

type StockWithHighestPrice = {
  id: string;
  code: string;
  description: string;
  highestUnitPrice: number | null;
  refInvoiceNo: string | null;     // invoice_no where the highest price was paid
  refInvoiceDate: string | null;   // invoice_date of that invoice
};

export default async function OrderPage() {
  const pb = getPb();
  let stockCodes: StockWithHighestPrice[] = [];
  let errorMsg: string | null = null;

  try {
    // 1) All stock codes (just the fields we need)
    const scRes = await pb.collection("JEI_stock_codes").getList(1, 5000, {
      sort: "code",
      fields: "id,code,description_goods",
    });

    // 2) All invoice lines + their parent invoice (so we can grab the
    //    invoice_no + invoice_date of whichever line carries the MAX
    //    unit_price for each stock code).
    //    PB only returns the expanded record when the field selector
    //    includes `expand.invoice.<field>`; `invoice` alone just returns
    //    the relation id and drops the expansion.
    const linesRes = await pb.collection("JEI_invoice_lines").getList(1, 5000, {
      expand: "invoice",
      fields: "id,stock_code,unit_price,expand.invoice.invoice_no,expand.invoice.invoice_date",
    });

    // 3) For each stock_code, keep the line with the highest unit_price
    //    and remember which invoice (no + date) it came from. Ties broken
    //    by most-recent invoice_date so the price source reflects the
    //    current market rather than an old historical peak.
    type Highest = { price: number; date: string; invNo: string };
    const highestByStock = new Map<string, Highest>();
    for (const line of linesRes.items) {
      const scId = line.stock_code as string;
      if (!scId) continue;
      const inv = line.expand?.invoice as any;
      const invNo: string = inv?.invoice_no || "";
      const invDate: string = inv?.invoice_date || "";
      const price = Number(line.unit_price) || 0;
      const cur = highestByStock.get(scId);
      const isHigher = !cur || price > cur.price;
      const isTieNewer =
        cur && price === cur.price && invDate > cur.date;
      if (isHigher || isTieNewer) {
        highestByStock.set(scId, { price, date: invDate, invNo });
      }
    }

    stockCodes = scRes.items.map((s: any) => {
      const h = highestByStock.get(s.id);
      return {
        id: s.id,
        code: s.code,
        description: s.description_goods || "",
        highestUnitPrice: h?.price ?? null,
        refInvoiceNo: h?.invNo || null,
        refInvoiceDate: h?.date ? h.date.slice(0, 10) : null,
      };
    });
  } catch (e: any) {
    errorMsg = String(e?.message || e);
  }

  return (
    <div className="space-y-6">
      {errorMsg ? (
        <div className="bg-red-50 border border-red-200 text-red-800 rounded p-4">
          <div className="font-semibold">Cannot reach PocketBase</div>
          <div className="text-sm mt-1">{errorMsg}</div>
        </div>
      ) : (
        <OrderClient stockCodes={stockCodes} />
      )}
    </div>
  );
}