frontend/src/entities/brokerage-account/model/display.ts

import type {
	BrokerageAccount,
	useBrokerageAccounts,
} from "../api/useBrokerageAccounts";

const VISIBLE_CURRENCY_LIMIT = 2;

type BrokerageAccountCard = {
	account: BrokerageAccount;
	positionCounts: null | { bonds: number; stocks: number };
	source?: NonNullable<
		ReturnType<typeof useBrokerageAccounts>["meta"]
	>["dependencies"] extends (infer T)[] | undefined
		? T
		: never;
	summary:
		| { remainingCurrencyCount: number; state: "available"; totals: Money[] }
		| { state: "empty" }
		| { state: "unavailable" };
};

type Money = NonNullable<
	BrokerageAccount["portfolioSummary"]
>["totalsByCurrency"][number];

function accountTypeKey(type: BrokerageAccount["type"]) {
	return `accounts.types.${type}` as const;
}

function brokerageAccountCards(
	accounts: BrokerageAccount[],
	dependencies: NonNullable<
		ReturnType<typeof useBrokerageAccounts>["meta"]
	>["dependencies"] = [],
): BrokerageAccountCard[] {
	return accounts.map((account) => {
		const source = dependencies.find(
			item =>
				item.resourceKey === `portfolio/${encodeURIComponent(account.id)}`,
		);
		const summary = account.portfolioSummary;
		if (!summary)
			return {
				account,
				positionCounts: /* eslint-disable-line unicorn/no-null -- The existing formatter contract uses null for unavailable data. */ null,
				source,
				summary: { state: "unavailable" },
			};
		const positionCounts = {
			bonds: summary.bondPositionCount,
			stocks: summary.stockPositionCount,
		};
		if (summary.totalsByCurrency.length === 0)
			return { account, positionCounts, source, summary: { state: "empty" } };
		return {
			account,
			positionCounts,
			source,
			summary: {
				remainingCurrencyCount: Math.max(
					summary.totalsByCurrency.length - VISIBLE_CURRENCY_LIMIT,
					0,
				),
				state: "available",
				totals: summary.totalsByCurrency.slice(0, VISIBLE_CURRENCY_LIMIT),
			},
		};
	});
}

export { accountTypeKey, type BrokerageAccountCard, brokerageAccountCards };