โครงสร้างโค้ดและตัวอ่านซอร์ส

import { createServerFn } from "@tanstack/react-start";

// Source of record for Thai gold pricing - the same realtime feed the original
// gold-price-th-tracker pulls from, so pricing stays in parity.
const FEED_URL = "https://thaigold.info/RealTimeDataV2/gtdata_.txt";

type FeedRow = {
  name: string;
  bid: string | number;
  ask: string | number;
  diff: string | number;
};

export type Quote = {
  bid: number | null;
  ask: number | null;
  diff: number | null;
};

export type GoldData = {
  goldBar: Quote; // ทองคำแท่ง 96.5%
  goldJewelry: Quote; // ทองรูปพรรณ 96.5%
  spot: Quote; // XAU/USD ($/oz)
  thb: Quote; // USD/THB
  updatedAt: number; // epoch ms
  ok: boolean;
};

function toNum(v: string | number | null | undefined): number | null {
  if (v === null || v === undefined) return null;
  if (typeof v === "number") return Number.isFinite(v) ? v : null;
  const cleaned = v.toString().replace(/[+,\s]/g, "");
  if (cleaned === "") return null;
  const n = Number(cleaned);
  return Number.isFinite(n) ? n : null;
}

function quote(row: FeedRow | undefined): Quote {
  if (!row) return { bid: null, ask: null, diff: null };
  return { bid: toNum(row.bid), ask: toNum(row.ask), diff: toNum(row.diff) };
}

function parseFeed(rows: FeedRow[]): GoldData {
  const byName = new Map<string, FeedRow>();
  for (const r of rows) byName.set(r.name, r);

  // "สมาคมฯ" = gold bar 96.5% (ทองคำแท่ง); "96.5%" = jewelry (ทองรูปพรรณ).
  const goldBar = quote(byName.get("สมาคมฯ"));
  const goldJewelry = quote(byName.get("96.5%"));
  const spot = quote(byName.get("GoldSpot"));
  const thb = quote(byName.get("THB"));

  // The "Update" row carries the feed timestamp in its bid (unix seconds).
  const update = byName.get("Update");
  const ts = toNum(update?.bid);
  const updatedAt = ts ? ts * 1000 : Date.now();

  return {
    goldBar,
    goldJewelry,
    spot,
    thb,
    updatedAt,
    ok: goldBar.ask !== null || goldJewelry.ask !== null,
  };
}

export const getGoldData = createServerFn({ method: "GET" }).handler(
  async (): Promise<GoldData> => {
    try {
      const res = await fetch(FEED_URL, {
        signal: AbortSignal.timeout(9000),
        headers: { Accept: "application/json, text/plain, */*" },
      });
      if (!res.ok) throw new Error(`feed ${res.status}`);
      const text = await res.text();
      const rows = JSON.parse(text) as FeedRow[];
      if (!Array.isArray(rows)) throw new Error("bad feed shape");
      return parseFeed(rows);
    } catch {
      return {
        goldBar: { bid: null, ask: null, diff: null },
        goldJewelry: { bid: null, ask: null, diff: null },
        spot: { bid: null, ask: null, diff: null },
        thb: { bid: null, ask: null, diff: null },
        updatedAt: Date.now(),
        ok: false,
      };
    }
  },
);