export function parseLemfiQuote(result) {
    const quote = result?.data;
    if (quote?.exchange_from !== "EUR" || quote?.exchange_to !== "NGN") {
        throw new Error("LemFi did not return a EUR to NGN quote");
    }

    // Match LemFi's calculator: divide the encoded rate by the digits in its ID.
    // Use the base rate so referral rewards and LemFi Cash do not inflate comparisons.
    const divisor = typeof quote.ID === "string" ? Number(quote.ID.replace(/\D/g, "")) : 0;
    const encodedRate = typeof quote.rate === "string" || typeof quote.rate === "number"
        ? Number(quote.rate)
        : NaN;
    const rate = encodedRate / divisor;
    if (!Number.isFinite(divisor) || divisor <= 0 || !Number.isFinite(rate) || rate <= 0) {
        throw new Error("LemFi returned an invalid exchange rate");
    }

    return rate;
}

export async function fetchLemfiRate() {
    const url = new URL("https://lemfi.com/api/exchange-quote");
    url.search = new URLSearchParams({ from: "EUR", to: "NGN", country: "Netherlands", lang: "en" });
    const response = await fetch(url, {
        headers: { accept: "application/json" },
        signal: AbortSignal.timeout(8000),
    });
    if (!response.ok) {
        throw new Error(`LemFi quote request failed (${response.status})`);
    }

    return parseLemfiQuote(await response.json());
}