const {toNumber} = require("./typeTool_cjs");
const {handle} = require("./handle_cjs");
const codeMap = require("../map/rcodeMap");
function limitSql (limit = 20,page = 1){
  let sql = '';
  let values = [];
  limit = toNumber(limit);
  page = toNumber(page);
  limit = limit || 20;
  page = page || 1;
  sql += ` limit ?,?`;
  values.push(limit * (page - 1),limit)
  return {sql,values}
}
/**
 * 封装搜索数据库字段
 * @param errorText
 * @param dbFn
 * @param _params
 * @param _sort
 * @param page
 * @param limit
 * @param listChangeHandle
 * @returns {Promise<[err,{arr, total: number, limit, page}]>}
 */
async function searchHandle(errorText,dbFn,_params,_sort,page,limit ,
                            listChangeHandle = null
){
    let err,response,arrPromise,countPromise;
    limit = toNumber(limit);
    page = toNumber(page);
    limit = limit||20;
    page = page||1;
    arrPromise = dbFn('array', _params, _sort, page, limit);
    if(page <= 1){
        // 添加计数字段
        countPromise = dbFn('count',_params);
        [err,response] = await handle(Promise.all([arrPromise,countPromise]))
    }else{
        [err,response] = await handle(Promise.all([arrPromise]))
    }
    if(err){
        return [
          {eCode:codeMap.ServerError,eMsg:`${errorText}`,eDetail:err.message},
          null
        ]
    }
    let arr = response[0];
    if(listChangeHandle){
        arr = arr.map(listChangeHandle)
    }
    let  result = {
        arr: arr,
        limit: limit,
        page: page,
        total: 0
    }
    if(page <= 1){
        result.total = response[1]?response[1][0].total:null
    }
    return [null,result];
}

function searchSql (fn,type,sql,values,limit,page){
  // 添加分页
  if(type==='array'){
    let _limitSql = limitSql(limit,page);
    sql += _limitSql.sql;
    values.push(..._limitSql.values);
  }
  return fn(sql,values)
}

/**
 * 参数转化为防止sql注入的字符串
 * @param str
 * @returns {string|*}
 */
function toSqlString (str){
  if(!str){
    return '';
  }
  return str.replace(/'/g,"\\'")
}

module.exports = {
  limitSql,
  searchHandle,
  searchSql,
  toSqlString
}