// JSON Schema 校验 — 验证 AI 返回的 JSON 结构
const schemas = {
  purchase: { required: ['purchase_item'], optional: ['quantity','unit_price','freight','payment_method','invoice_type','status','applicant','remarks','created_time','is_new','use_recent_image'] },
  query: { required: [], optional: [] },
  chat: { required: ['reply'], optional: [] },
  delete: { required: ['delete_item'], optional: ['quantity','amount'] },
  clear_all: { required: [], optional: [] },
  ignore: { required: [], optional: [] },
};

function validate(aiResult) {
  if (!aiResult || !aiResult.action) {
    return { valid: false, error: '缺少 action 字段' };
  }
  const schema = schemas[aiResult.action];
  if (!schema) {
    return { valid: false, error: `未知 action: ${aiResult.action}` };
  }
  for (const field of schema.required) {
    if (aiResult[field] === undefined || aiResult[field] === null) {
      return { valid: false, error: `action=${aiResult.action} 缺少必填字段: ${field}` };
    }
  }
  return { valid: true };
}

// 修复常见问题
function normalize(aiResult) {
  // action="ask" 兼容 reply/question
  if (aiResult.action === 'ask') {
    aiResult.question = aiResult.question || aiResult.reply || '请提供更多信息。';
  }
  // chat 兼容 reply 为空
  if (aiResult.action === 'chat' && !aiResult.reply) {
    aiResult.reply = '好的。';
  }
  return aiResult;
}

module.exports = { validate, normalize };