feat(gold): show buy and sell prices in portfolio

internal/modules/gold/handlers.go

@@ -184,11 +184,12 @@ func (s *state) handleStats(ctx context.Context, b *bot.Bot, update *models.Upda
 	// Fetch under a reply-reserved sub-context; reply on the original ctx.
 	fetchCtx, cancel := chathelper.FetchContext(ctx)
 	defer cancel()
-	if buyPrice, _, err := s.prices.FetchLuongPrices(fetchCtx); err == nil {
+	if buyPrice, sellPrice, err := s.prices.FetchLuongPrices(fetchCtx); err == nil {
 		goldValue := p.Luong * buyPrice
 		totalValue += goldValue
-		lines = append(lines, "Price: "+FormatVND(buyPrice)+"/luong")
-		lines = append(lines, "Gold value: "+FormatVND(goldValue))
+		lines = append(lines, "SJC buy (you sell): "+FormatVND(buyPrice)+"/luong")
+		lines = append(lines, "SJC sell (you buy): "+FormatVND(sellPrice)+"/luong")
+		lines = append(lines, "Gold value (at SJC buy): "+FormatVND(goldValue))
 		lines = append(lines, "Total value: "+FormatVND(totalValue))
 		lines = append(lines, "Invested: "+FormatVND(p.Meta.Invested))
 		lines = append(lines, "P&L: "+FormatPnL(totalValue, p.Meta.Invested))

internal/modules/gold/handlers_test.go

@@ -159,7 +159,14 @@ func TestStatsWithAndWithoutPrice(t *testing.T) {
 		t.Fatalf("stats: %v", err)
 	}
 	text := rb.LastSent().Text()
-	for _, want := range []string{"Gold Account Summary", "Gold: 1 luong", "Price: 2.000.000 VND/luong", "P&L:"} {
+	for _, want := range []string{
+		"Gold Account Summary",
+		"Gold: 1 luong",
+		"SJC buy (you sell): 2.000.000 VND/luong",
+		"SJC sell (you buy): 2.000.000 VND/luong",
+		"Gold value (at SJC buy): 2.000.000 VND",
+		"P&L:",
+	} {
 		if !strings.Contains(text, want) {
 			t.Fatalf("stats missing %q in %q", want, text)
 		}
@@ -172,6 +179,33 @@ func TestStatsWithAndWithoutPrice(t *testing.T) {
 	rb.AssertSentText(t, "Price: no price")
 }
 
+func TestHandleStatsShowsBuyAndSellPrices(t *testing.T) {
+	ctx := context.Background()
+	s := &state{
+		store:  newGoldStore(),
+		prices: spreadPriceFetcher{buy: 90_000_000, sell: 91_000_000},
+		nowFn:  func() time.Time { return time.UnixMilli(123) },
+	}
+	rb := testutil.NewRecordingBot(t)
+	_ = s.handleTopup(ctx, rb.Bot, testutil.NewPrivateMessage(7, "/gold_topup 500000000"))
+	_ = s.handleBuy(ctx, rb.Bot, testutil.NewPrivateMessage(7, "/gold_buy 1"))
+	rb.Reset()
+	if err := s.handleStats(ctx, rb.Bot, testutil.NewPrivateMessage(7, "/gold_portfolio")); err != nil {
+		t.Fatalf("stats: %v", err)
+	}
+	text := rb.LastSent().Text()
+	for _, want := range []string{
+		"SJC buy (you sell): 90.000.000 VND/luong",
+		"SJC sell (you buy): 91.000.000 VND/luong",
+		"Gold value (at SJC buy): 90.000.000 VND",
+		"Total value: 499.000.000 VND",
+	} {
+		if !strings.Contains(text, want) {
+			t.Fatalf("stats missing %q in %q", want, text)
+		}
+	}
+}
+
 // spreadPriceFetcher returns different buy/sell prices so handler tests can
 // verify that buys use the sell price and sells use the buy price.
 type spreadPriceFetcher struct {