import fetch from 'node-fetch';

const NHTSA_BASE = 'https://vpic.nhtsa.dot.gov/api/vehicles/DecodeVinValues';
const TTL_SECONDS = 90 * 24 * 60 * 60; // 90 days

/** Fetch decoded VIN data from NHTSA vPIC */
export async function fetchFromNhtsa(vin) {
  const url = `${NHTSA_BASE}/${encodeURIComponent(vin)}?format=json`;
  const res = await fetch(url, { timeout: 10000 });
  if (!res.ok) throw new Error(`NHTSA returned HTTP ${res.status}`);
  const json = await res.json();
  const results = json.Results?.[0];
  if (!results) throw new Error('NHTSA returned empty Results array');
  return results;
}

/** Map NHTSA flat key/value response to our schema */
export function mapNhtsaToSchema(raw) {
  const cc = raw.DisplacementCC ? parseFloat(raw.DisplacementCC) : null;
  const litre = raw.DisplacementL ? parseFloat(raw.DisplacementL) : null;
  const cylinders = raw.EngineCylinders ? parseInt(raw.EngineCylinders, 10) : null;
  return {
    make: raw.Make || null,
    model: raw.Model || null,
    model_year: raw.ModelYear || null,
    trim: raw.Trim || null,
    series: raw.Series || null,
    body_class: raw.BodyClass || null,
    drive_type: raw.DriveType || null,
    engine_displacement_cc: isNaN(cc) ? null : cc,
    engine_displacement_l: isNaN(litre) ? null : litre,
    engine_cylinders: isNaN(cylinders) ? null : cylinders,
    fuel_type_primary: raw.FuelTypePrimary || null,
    transmission_style: raw.TransmissionStyle || null,
    transmission_speeds: raw.TransmissionSpeeds || null,
    plant_city: raw.PlantCity || null,
    plant_state: raw.PlantState || null,
    plant_country: raw.PlantCountry || null,
    manufacturer_name: raw.Manufacturer || null,
    vehicle_type: raw.VehicleType || null,
    error_code: raw.ErrorCode || '0',
    error_text: raw.ErrorText || null,
  };
}

export { TTL_SECONDS };