function safeParseJson(value) {
  if (typeof value !== "string" || !value.trim()) return null;
  try {
    const parsed = JSON.parse(value);
    return parsed && typeof parsed === "object" && !Array.isArray(parsed) ? parsed : null;
  } catch (error) {
    return null;
  }
}

function formatReport(value) {
  if (value == null) return "";
  const parsed = typeof value === "string" ? safeParseJson(value) : value;
  if (parsed == null) return typeof value === "string" ? value : "";
  try {
    return JSON.stringify(parsed, null, 2);
  } catch (error) {
    return String(value);
  }
}

function normalizeCriteria(value) {
  if (!Array.isArray(value)) return [];
  return value.map((item) => {
    if (typeof item === "string") return { name: item, score: "", description: "" };
    return {
      name: String(item?.name || item?.criterion || item?.title || "评分项"),
      score: item?.score ?? item?.weight ?? "",
      description: String(item?.description || item?.detail || ""),
    };
  });
}

function normalizeOperation(operation, root, type) {
  const value = operation && typeof operation === "object" ? operation : {};
  const prefix = type === "help" ? "help" : "assessment";
  const flatReportKey = type === "help" ? "helpReportJson" : "assessmentReportJson";
  return {
    ...value,
    status: String(value.status || root?.[`${prefix}Status`] || "PENDING").toUpperCase(),
    report: value.report || root?.[flatReportKey] || root?.[`${prefix}Report`] || "",
    scoreCriteria: value.scoreCriteria || root?.scoreCriteria || [],
  };
}

function normalizeEvaluationReports(evaluation) {
  const root = evaluation && typeof evaluation === "object" ? evaluation : {};
  const help = normalizeOperation(root.help || root.helpEvaluation, root, "help");
  const assessment = normalizeOperation(root.assessment || root.assessmentEvaluation, root, "assessment");
  const assessmentReportData = safeParseJson(root.assessmentReportJson);

  return {
    help,
    assessment,
    helpReport: formatReport(help.report || help.content || help.suggestion),
    assessmentReport: formatReport(assessment.report || assessment.content || assessment.feedback),
    score: root.assessmentScore ?? assessment.score ?? assessmentReportData?.score ?? root.score ?? null,
    scoreCriteria: normalizeCriteria(assessmentReportData?.criteria || assessment.scoreCriteria || root.scoreCriteria),
  };
}

module.exports = {
  formatReport,
  normalizeCriteria,
  normalizeEvaluationReports,
  normalizeOperation,
  safeParseJson,
};