/**
 * Recontextualize text or response object by replacing placeholders with original values.
 * @param {string} text - String that may contain placeholders (e.g. PII_0, PII_1)
 * @param {Array<{ placeholder: string, value: string }>} mapping - From anonymize()
 * @returns {string}
 */
function recontextualizeText(text, mapping) {
  if (text === null || text === undefined || typeof text !== "string") return text;
  let out = text;
  for (const m of mapping) {
    const re = new RegExp(escapeRegex(m.placeholder), "g");
    out = out.replace(re, m.value);
  }
  return out;
}

/**
 * Recontextualize full response object (4 fields).
 * @param {object} response - { answer, nextActionsTable, membersInfoSheet, synthesisRecommendation }
 * @param {Array<{ placeholder: string, value: string }>} mapping
 * @returns {object}
 */
function recontextualizeResponse(response, mapping) {
  if (!response || !mapping || mapping.length === 0) return response;
  const out = { ...response };
  if (typeof out.answer === "string") out.answer = recontextualizeText(out.answer, mapping);
  if (typeof out.nextActionsTable === "string") out.nextActionsTable = recontextualizeText(out.nextActionsTable, mapping);
  if (typeof out.membersInfoSheet === "string") out.membersInfoSheet = recontextualizeText(out.membersInfoSheet, mapping);
  if (typeof out.synthesisRecommendation === "string") out.synthesisRecommendation = recontextualizeText(out.synthesisRecommendation, mapping);
  return out;
}

function escapeRegex(s) {
  return String(s).replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
}

module.exports = { recontextualizeText, recontextualizeResponse };