refactor: clarify frontend module ownership

src/pages/account/model/previews.ts

@@ -0,0 +1,144 @@
+import type { BrokerageOperation } from "@/entities/broker-operation";
+import type {
+	BrokerageEvent,
+	BrokerageEventsPreviewState,
+} from "@/entities/brokerage-event";
+import type { IncomeSummary } from "@/entities/income";
+import type { InvestmentResourceMeta } from "@/shared/api";
+
+const RECENT_EVENTS_LIMIT = 5;
+
+type AccountPageIncomeSummary
+	= | {
+		lastSuccessfulAt?: null | string;
+		refreshError?: boolean;
+		stale?: boolean;
+		state: "loaded";
+		summary: IncomeSummary;
+		to: string;
+	}
+	| { retry: () => Promise<unknown> | undefined; state: "error"; to: string }
+	| {
+		state: "empty"
+			| "loading"
+			| "partial";
+		to: string;
+	};
+
+type AccountPageRecentEvents = BrokerageEventsPreviewState;
+
+type AccountPageRecentOperations
+	= | {
+		items: BrokerageOperation[];
+		lastSuccessfulAt?: null | string;
+		refreshError?: boolean;
+		stale?: boolean;
+		state: "loaded" | "partial";
+		to: string;
+	}
+	| {
+		state: "empty"
+			| "error"
+			| "loading";
+		to: string;
+	};
+
+type PreviewResource<T> = {
+	data?: T;
+	isError: boolean;
+	meta?: Pick<InvestmentResourceMeta,
+	"availability"
+	| "freshness"
+	| "lastSuccessfulAt"
+	| "sync"
+	>;
+};
+
+function toIncomeSummary(
+	accountId: string | undefined,
+	income: PreviewResource<IncomeSummary>,
+	retry: () => Promise<unknown>,
+): AccountPageIncomeSummary {
+	const to = `/accounts/${accountId}/income`;
+	if (!income.data && !income.isError && income.meta?.sync.state !== "failed")
+		return { state: "loading", to };
+	if (income.meta?.availability === "partial") return { state: "partial", to };
+	if (!income.data && (income.isError || income.meta?.sync.state === "failed"))
+		return { retry, state: "error", to };
+	if (!income.data?.totalsByCurrency.length) return { state: "empty", to };
+
+	return {
+		lastSuccessfulAt: income.meta?.lastSuccessfulAt,
+		refreshError: income.isError || income.meta?.sync.state === "failed",
+		stale: income.meta?.freshness === "stale",
+		state: "loaded",
+		summary: income.data,
+		to,
+	};
+}
+
+function toRecentEvents(
+	accountId: string | undefined,
+	events: PreviewResource<{ events: BrokerageEvent[] }>,
+): AccountPageRecentEvents {
+	const to = `/accounts/${accountId}/events`;
+	if (!events.data && !events.isError && events.meta?.sync.state !== "failed")
+		return { state: "loading", to };
+	if (events.meta?.availability === "partial")
+		return {
+			items: events.data?.events.slice(0, RECENT_EVENTS_LIMIT) ?? [],
+			state: "partial",
+			to,
+		};
+	if (!events.data && (events.isError || events.meta?.sync.state === "failed"))
+		return { state: "error", to };
+	const items = events.data?.events.slice(0, RECENT_EVENTS_LIMIT) ?? [];
+	if (items.length === 0) return { state: "empty", to };
+
+	return {
+		items,
+		lastSuccessfulAt: events.meta?.lastSuccessfulAt,
+		refreshError: events.isError || events.meta?.sync.state === "failed",
+		stale: events.meta?.freshness === "stale",
+		state: "loaded",
+		to,
+	};
+}
+
+function toRecentOperations(
+	accountId: string | undefined,
+	operations: PreviewResource<{ items: BrokerageOperation[] }>,
+): AccountPageRecentOperations {
+	const to = `/accounts/${accountId}/operations`;
+	if (
+		!operations.data
+		&& !operations.isError
+		&& operations.meta?.sync.state !== "failed"
+	)
+		return { state: "loading", to };
+	if (operations.meta?.availability === "partial")
+		return { items: operations.data?.items ?? [], state: "partial", to };
+	if (
+		!operations.data
+		&& (operations.isError || operations.meta?.sync.state === "failed")
+	)
+		return { state: "error", to };
+	if (!operations.data?.items.length) return { state: "empty", to };
+
+	return {
+		items: operations.data.items,
+		lastSuccessfulAt: operations.meta?.lastSuccessfulAt,
+		refreshError:
+			operations.isError || operations.meta?.sync.state === "failed",
+		stale: operations.meta?.freshness === "stale",
+		state: "loaded",
+		to,
+	};
+}
+
+export { toIncomeSummary, toRecentEvents, toRecentOperations };
+export type {
+	AccountPageIncomeSummary,
+	AccountPageRecentEvents,
+	AccountPageRecentOperations,
+};