feat: make brokerage account list compact (#111)

src/shared/lib/display.ts

@@ -2,6 +2,7 @@ const DECIMAL_PART_COUNT = 2;
 const CENTS_PRECISION = 2;
 
 type FormatMoneyOptions = {
+	withRoundedCents?: boolean;
 	withZeroCents?: boolean;
 };
 
@@ -39,16 +40,20 @@ function formatMoney(
 	money: Money
 		| null
 		| undefined,
-	{ withZeroCents = false }: FormatMoneyOptions = {},
+	{ withRoundedCents = false, withZeroCents = false }: FormatMoneyOptions = {},
 ): string {
 	if (!money) return "—";
 
-	const [integerPart = "", fractionPart = ""] = money.value.split(
+	const value = withRoundedCents
+		? roundDecimalToCents(money.value)
+		: money.value;
+
+	const [integerPart = "", fractionPart = ""] = value.split(
 		".",
 		DECIMAL_PART_COUNT,
 	);
 
-	const normalizedFraction = withZeroCents
+	const normalizedFraction = withRoundedCents || withZeroCents
 		? fractionPart.padEnd(CENTS_PRECISION, "0")
 		: fractionPart;
 
@@ -61,6 +66,23 @@ function formatMoney(
 	return `${formatDecimal(decimal)} ${currency}`;
 }
 
+function roundDecimalToCents(value: string): string {
+	const [integer = "", fraction = ""] = value.split(".", DECIMAL_PART_COUNT);
+	const sign = integer.startsWith("-") ? "-" : "";
+	const digits = sign ? integer.slice(1) : integer;
+	const roundedFraction = fraction.padEnd(CENTS_PRECISION + 1, "0");
+	const cents = `${digits}${roundedFraction.slice(0, CENTS_PRECISION)}`;
+	const roundingDigit = roundedFraction.at(CENTS_PRECISION) ?? "0";
+
+	const rounded = roundingDigit >= "5"
+		? (BigInt(cents) + 1n).toString().padStart(cents.length, "0")
+		: cents;
+
+	const roundedInteger = rounded.slice(0, -CENTS_PRECISION) || "0";
+
+	return `${sign}${roundedInteger}.${rounded.slice(-CENTS_PRECISION)}`;
+}
+
 // Без timeZone Intl берёт часовой пояс браузера пользователя.
 const snapshotFormatter = new Intl.DateTimeFormat("ru-RU", {
 	dateStyle: "short",