import express from "express";
import mysql from "mysql";
/**
 * 401 需要跳转登录验证
 * 500 接口错误
 */
const app = express();
const mysqlParams = {
    host: '123.57.147.184',
    port: '3306',
    user: 'root',
    password: 'Xg137839',
    connectTimeout: 10000
};
// 连接 mysql 数据库
const connection = (database) => {
    return mysql.createConnection({
        ...mysqlParams,
        database: database || ''
    });
}
// 连接 mysql
const con = mysql.createConnection({
    ...mysqlParams
});



// 查询数据方法 SELECT * FROM table
const m_get = (table, Clause, order, start, end) => {
    return `SELECT * FROM ${table} ${Clause ? 'WHERE ' + Clause : ``} ORDER BY ${order || `ID`} DESC ${!end ? `` : `LIMIT ` + start + `,` + end};`
}
// 插入数据方法 INSERT INTO table_name ( field1, field2,...fieldN ) VALUES ( value1, value2,...valueN );
const m_add = (table, field, value) => {
    return `INSERT INTO ${table} ( ${field} ) VALUES ( ${value} );`
}
// 更新数据方法 UPDATE table_name SET field1=new-value1, field2=new-value2 [WHERE Clause]
const m_update = (table, data, Clause) => {
    return `UPDATE ${table} SET ${data} WHERE ${Clause};`
}
// 删除数据方法 DELETE FROM table_name [WHERE Clause]
const m_delete = (table, Clause) => {
    return `DELETE FROM ${table} WHERE ${Clause};`
}

const nowTime = () => {
    const now = new Date();
    const year = now.getFullYear();
    const month = now.getMonth();
    const date = now.getDate() >= 10 ? now.getDate() : ('0' + now.getDate());
    const hour = now.getHours() >= 10 ? now.getHours() : ('0' + now.getHours());
    const miu = now.getMinutes() >= 10 ? now.getMinutes() : ('0' + now.getMinutes());
    const sec = now.getSeconds() >= 10 ? now.getSeconds() : ('0' + now.getSeconds());
    return +year + "-" + (month + 1) + "-" + date + " " + hour + ":" + miu + ":" + sec;
}

/**
 * 格式化时间
 * @returns
 */
const dateFormater = (formater, time) => {
    let date = time ? new Date(time) : new Date(),
        Y = date.getFullYear() + '',
        M = date.getMonth() + 1,
        D = date.getDate(),
        H = date.getHours(),
        m = date.getMinutes(),
        s = date.getSeconds();
    return formater.replace(/YYYY|yyyy/g, Y)
        .replace(/YY|yy/g, Y.substr(2, 2))
        .replace(/MM/g, (M < 10 ? '0' : '') + M)
        .replace(/DD|dd/g, (D < 10 ? '0' : '') + D)
        .replace(/HH|hh/g, (H < 10 ? '0' : '') + H)
        .replace(/mm/g, (m < 10 ? '0' : '') + m)
        .replace(/ss/g, (s < 10 ? '0' : '') + s)
}

// 获取数据库列表
const getDatabases = () => app.post('/getdatabases', function (req, res) {
    // con.connect();
    con.query("SHOW DATABASES", function (error, results, fields) {
        if (error) {
            console.log(`${nowTime()} 错误：${JSON.stringify(error)}`);
            return res.status(500).send(error);
        } else {
            res.send(results);
            // con.end();
        }
    });
});

// 公共查询方法
const mysqlQuery = (res, database, sql) => {
    if (!database) return res.status(500).send('database is ' + database);
    try {
        connection(database).connect();
        connection(database).query(sql, (error, results, fields) => {
            if (error) {
                console.log(`${nowTime()} 错误：${JSON.stringify(error)}`);
                return res.status(500).send(error);
            } else {
                res.send(results);
            }
            connection(database).end();
        });
        
    } catch (error) {
        console.log(error);
        return res.status(500).send('连接失败', error);
    }
}

export default {
    app,
    connection,
    con,
    mysqlQuery,
    m_get,
    m_add,
    m_update,
    m_delete,
    nowTime,
    dateFormater,
    getDatabases
};