import { emptySpec, normalizeToken } from './spec.js';
import { VENDOR_TABLES } from './pn-tables.js';

/**
 * Leitet aus einer Hersteller-Teilenummer die Spec-Felder ab.
 * Nicht ableitbare Felder bleiben null - das ist kein Fehler,
 * sondern der regulaere Uebergang zum OCR-Weg.
 */
export function decodePartNumber(pn) {
  const spec = emptySpec();
  const normalized = normalizeToken(pn);
  if (normalized === '') return spec;

  spec.partNumber = normalized;

  for (const table of VENDOR_TABLES) {
    const match = normalized.match(table.pattern);
    if (!match) continue;

    const [, formCode, densityCode, speedCode] = match;

    spec.formFactor = table.formFactor[formCode] ?? null;
    spec.speed = table.speed[speedCode] ?? null;

    const density = table.density[densityCode];
    if (density) {
      spec.capacityGb = density.capacityGb;
      spec.rank = density.rank;
    }
    break;
  }

  return spec;
}