const db = require("./db");
const utils = require("./utils");

async function update(tblName, whereList, fieldList) {
  const params = [];
  let sql = 'UPDATE `' + tblName + '` SET ';

  fieldList.forEach((item, index) => {
    const suffix = (index + 1 < fieldList.length ? ',': '');
    sql += ' `' + item[0] + '`=?' + suffix;
    params.push(item[1]);
  });

  sql += ' WHERE 1=1';
  whereList.forEach((item, index) => {
    sql += ' AND ' + item[0] + '=?';
    params.push(item[1]);
  });

  return db.execScript(sql, params);
}

async function mustBeUpdate(tblName, whereList, fieldList, time) {
  while (true) {
    const err = await update(tblName, whereList, fieldList, );
    if (!err) {
      return err;
    } else {
      await utils.sleep(time);
    }
  }
}

async function insert(tblName, fieldList) {
  const params = [];
  let sql = 'INSERT INTO `' + tblName + '` (';

  fieldList.forEach((item, index) => {
    const suffix = (index + 1 < fieldList.length ? ',': '');
    sql += '`' + item[0] + '`' + suffix;
  });

  sql += ') VALUES (';
  fieldList.forEach((item, index) => {
    const suffix = (index + 1 < fieldList.length ? ',': '');
    sql += '?' + suffix;
    params.push(item[1]);
  });
  sql += ')';

  return db.execScript(sql, params);
}

async function mustBeInsert(tblName, fieldList, time) {
  while (true) {
    const err = await insert(tblName, fieldList);
    if (!err) {
      return err;
    } else {
      await utils.sleep(time);
    }
  }
}

async function _delete(tblName, whereList) {
  const params = [];
  let sql = 'DELETE FROM `' + tblName + '` ';

  sql += ' WHERE 1=1';
  whereList.forEach((item, index) => {
    sql += ' AND ' + item[0] + '=?';
    params.push(item[1]);
  });

  return db.execScript(sql, params);
}

async function ormSelect(tblName, whereList) {
  const params = [];
  let sql = 'SELECT * FROM `' + tblName + '` ';

  sql += ' WHERE 1=1';
  whereList.forEach((item, index) => {
    sql += ' AND `' + item[0] + '`=?';
    params.push(item[1]);
  });

  return db.execQuery(sql, params);
}

async function ormSelectOne(tblName, whereList) {
  const {err, rows} = await ormSelect(tblName, whereList);
  return {
    'err': err,
    'row': rows.length > 0 ? rows[0] : null
  };
}

async function mustBeOrmSelectOne(tblName, whereList, time) {
  while (true) {
    const {err, row} = await ormSelectOne(tblName, whereList);
    if (!err) {
      return {
        'err': err,
        'row': row
      };
    } else {
      await utils.sleep(time);
    }
  }
}

exports.ormSelect = ormSelect;
exports.ormSelectOne = ormSelectOne;
exports.mustBeOrmSelectOne = mustBeOrmSelectOne;
exports.update = update;
exports.mustBeUpdate = mustBeUpdate;
exports.insert = insert;
exports.mustBeInsert = mustBeInsert;
exports._delete = _delete;