/**
   * @param {cqi.models.corpora.Corpus} corpus
   * @param {number[]} cposList
   * @returns {Promise<object>}
   */
async function lookupsByCpos(corpus, cposList) {
  let lookups = {};
  lookups['cpos_lookup'] = {};
  for (let cpos in cposList) {
    lookups['cpos_lookup'][cpos] = {};
  }

  let pAttrs = await corpus.positionalAttributes.list();
  for (let attr in pAttrs) {
    let values = await attr.valuesByCpos(cposList);
    for (let i = 0; i < cposList.length; i++) {
      let cpos = cposList[i];
      let value = values[i];
      lookups['cpos_lookup'][cpos][attr.name] = value;
    }
  }

  let sAttrs = await corpus.structuralAttributes.list();
  for (let attr in sAttrs) {
    // We only want to iterate over non subattributes, identifiable by
    // sAttr.hasValues == false
    if (attr.hasValues) {continue;}

    let idList = await attr.idsByCpos(cposList);
    for (let i = 0; i < cposList.length; i++) {
      let cpos = cposList[i];
      let id = idList[i];
      if (id == -1) {continue;}
      lookups['cpos_lookup'][cpos][attr.name] = id;
    }

    let occuredIdList = Array.from(new Set(idList.filter(x => x != -1)));
    if (occuredIdList.length == 0) {continue;}
  
    let subattrs = sAttrs.filter(x => x.name.startsWith(`${attr.name}_`));
    if (subattrs.length == 0) {continue;}

    let lookupName = `${attr.name}_lookup`;
    lookups[lookupName] = {};
    for (let id in occuredIdList) {
      lookups[lookupName][id] = {};
    }
    
    
  }

  return lookups;
}