import { isoly } from "isoly"
import { isly } from "isly"
import { Holidays } from "../../Holidays"
import { Treasury } from "../../Treasury"
import { Base } from "../Base"

export interface StaleFiat extends Base {
	type: "stale-fiat"
	severity?: "low"
	currency: isoly.Currency
	transaction: { id: string; created: isoly.DateTime }
}
export namespace StaleFiat {
	export const type = Base.type.extend<StaleFiat>({
		type: isly.string("stale-fiat"),
		severity: isly.string("low").optional(),
		currency: isly.string(),
		transaction: isly.object<StaleFiat["transaction"]>({ id: isly.string(), created: isly.string() }),
	})
	export function create(account: Treasury.Account, transactions: Treasury.Transaction[]): StaleFiat[] {
		const result: StaleFiat[] = []
		for (const [currency, amount] of Object.entries(account.balance)) {
			let oldest: { id: string; date: isoly.Date; created: isoly.DateTime } | undefined = undefined
			let remainder = amount
			for (const transaction of transactions) {
				if (transaction.amount > 0 && transaction.currency == currency && remainder > 0) {
					remainder = isoly.Currency.subtract(currency, remainder, transaction.amount)
					oldest = {
						id: transaction.id,
						date: isoly.DateTime.getDate(transaction.created),
						created: transaction.created,
					}
				} else if (remainder < 0) {
					break
				}
			}
			if (oldest && isoly.Date.now() > isoly.Date.nextBusinessDay(oldest.date, 3, Holidays.dates["England"])) {
				result.push({
					type: "stale-fiat",
					currency: currency as isoly.Currency,
					date: oldest.date,
					transaction: { id: oldest.id, created: oldest.created },
					resource: oldest.id,
				})
			}
		}
		return result
	}
}