import { Data, DataObject, DataPrimitiveArray, UsedKeys } from './types';

export const denormalize = (
  data: Data,
  normalizedData: { [key: string]: Data },
  usedKeys: UsedKeys,
  path = '',
): Data => {
  if (typeof data === 'string' && data.startsWith('@@')) {
    return denormalize(normalizedData[data], normalizedData, usedKeys, path);
  } else if (Array.isArray(data)) {
    return data.map(value =>
      denormalize(value, normalizedData, usedKeys, path),
    ) as DataPrimitiveArray | DataObject[];
  } else if (
    data !== null &&
    typeof data === 'object' &&
    !(data instanceof Date)
  ) {
    const objectEntries = usedKeys[path]
      ? Object.entries(data).filter(([k]) => usedKeys[path].includes(k))
      : Object.entries(data);

    return objectEntries.reduce((prev, [k, v]) => {
      prev[k] = denormalize(v, normalizedData, usedKeys, `${path}.${k}`);

      return prev;
    }, {} as DataObject);
  }

  return data;
};