export function pairKey(assetIn, assetOut) {
  return `${assetIn}->${assetOut}`;
}

export function classifyPairDirection({ assetIn, assetOut, btcAssetId, eureAssetId }) {
  if (assetIn === btcAssetId && assetOut === eureAssetId) return 'btc_to_eure';
  if (assetIn === eureAssetId && assetOut === btcAssetId) return 'eure_to_btc';
  return 'unsupported';
}

export function isActivePair(assetIn, assetOut, config) {
  return (
    (assetIn === config.tradingBtc.assetId && assetOut === config.tradingEure.assetId)
    || (assetIn === config.tradingEure.assetId && assetOut === config.tradingBtc.assetId)
  );
}

export function unitsToNumber(amount, decimals) {
  if (amount == null) return 0;
  const raw = String(amount).trim();
  if (!raw) return 0;

  const negative = raw.startsWith('-');
  const digits = negative ? raw.slice(1) : raw;
  const padded = digits.padStart(decimals + 1, '0');
  const head = padded.slice(0, padded.length - decimals);
  const tail = decimals > 0 ? padded.slice(-decimals) : '';
  const rendered = decimals > 0 ? `${head}.${tail}` : head;
  const numeric = Number(rendered);
  return negative ? -numeric : numeric;
}

export function numberToUnits(value, decimals, { mode = 'round' } = {}) {
  const factor = 10 ** decimals;
  const scaled = value * factor;

  if (mode === 'floor') return String(Math.max(0, Math.floor(scaled)));
  if (mode === 'ceil') return String(Math.max(0, Math.ceil(scaled)));
  return String(Math.max(0, Math.round(scaled)));
}

export function bigintAmount(amount) {
  return BigInt(String(amount || '0'));
}

export function formatNumber(value, digits = 8) {
  if (!Number.isFinite(value)) return null;
  return value.toFixed(digits);
}

export function mapToSortedObject(record = {}) {
  return Object.fromEntries(
    Object.entries(record).sort(([left], [right]) => left.localeCompare(right)),
  );
}