/*
 * @Author: Dongge
 * @Date: 2019-05-16 10:35:38
 * @LastEditTime: 2019-05-24 09:56:04
 * @Description: server for front-end,mock--getfpdjson V1.0
 */
// 经过和node-oracle 模块作者的讨论，合理配置了连接池参数，poolMax:连接池最大保持连接数，需要小于128，poolMin:连接池最小存活连接，poolPingInterval:探活时间，poolTimeout：连接被销毁时间，0为永远不销毁，针对个人开发测试，推荐永远不销毁。--20190520
// 同步和异步ajax测试均通过，模拟原始getresult接口的datasorce成功，增加数据库信息配置文件datasource.ini,增加读取配置文件功能 --20150523
// 编写批处理启动server.cmd，整合运行环境:nodejs包，oracle客户端包instantclient_11_2，发布版V1.0 --20150524
var http = require('http');
var oracledb = require("oracledb");
var fs = require("fs");
var readline = require("readline");

var path = require('path')
var querystring = require('querystring')

oracledb.poolMax = 100;
oracledb.poolMin = 1;
oracledb.poolPingInterval = 20;
oracledb.poolTimeout = 0;

process
    .once('SIGTERM', closePoolAndExit)
    .once('SIGINT', closePoolAndExit);

// readFile 读取文件函数，返回promise
var readFile = async function (path) {
    var rl = readline.createInterface({
        input: fs.createReadStream(path).setEncoding('utf8')
    });
    return new Promise((resolve, reject) => {
        var array = [];
        rl.on("line", line => {
            array.push(line);
        });
        rl.on("close", () => {
            resolve(array);
        });
    });
};

// 初始化连接池
var pool = {};

var initPool = async function () {
    // var dbconfig = await readFile('./datasource.ini');
    // for (var i = 0; i < dbconfig.length; i++) {
    //     var temp = dbconfig[i].split(',');
        try {
            await oracledb.createPool({
                _enableStats: true,
                user: "HLWYY",
                password: 'Xmykzxhlwyy963',  // mypw contains the hr schema password
                connectString: "10.10.10.16:1521/rac",
                poolAlias: "im"
            });
            pool["im"] = true;
        } catch (err) {
            pool["im"] = false;
            console.error(err.message);
            throw new Error('连接池"im"创建失败！");
        }
    // }
}
//退出执行函数
async function closePoolAndExit() {
    console.log("\nTerminating");
    try {
        for(var key in pool){
            await oracledb.getPool(key).close(10);
        }
        process.exit(0);
    } catch (err) {
        console.error(err.message);
        process.exit(1);
    }
}
//查询函数
var executeSql = async function (dataSource, sql) {
    var pool_flag = pool[dataSource];
    if (!pool_flag) {
        return
    }

    var pool_name = oracledb.getPool(dataSource);
    try {
        var connection = await pool_name.getConnection();
        let result = await connection.execute(sql);
        await connection.close();
        return Promise.resolve(result);
    } catch (err) {
        console.log(err.message)
    }

};
(async () => {
    await initPool();
//启动服务器
    var server = http.createServer((req, res) => {
        if (req.url === "/getResult") {
            // 跨域，null是开启本地直接访问服务器特权
            res.setHeader('Access-Control-Allow-Origin', 'null');

            var params = '';
            req.setEncoding('utf8');
            // 采用post请求，接收前端的参数，这里考虑到sql里面可能有汉字，所以前端传过来的是编码后的JSON字符串。
            req.on('data', function (chunk) {
                params += chunk;
            });
            req.on('end', () => {
                params = decodeURIComponent(unescape(params));
                var { sql, dataSource } = JSON.parse(params);
                (async () => {
                    try {
                        var { metaData, rows } = await executeSql(dataSource, sql);
                        var data = [];
                        for (var i = 0; i < rows.length; i++) {
                            var temp = {}
                            for (var j = 0; j < metaData.length; j++) {
                                temp[metaData[j]['name']] = rows[i][j];
                            }
                            data.push(temp);
                        }
                        var dataReturn = { flag: 1, data: data }
                        res.end(JSON.stringify(dataReturn));
                    } catch (err) {
                        res.end(JSON.stringify({ flag: 0, data: err.message }));
                    }
                })();
            })

        } else if (req.url === "/getlog") {
            //查看连接池状态信息接口，暂时写死了别名，调试用的，需要换成你自己的别名。
            oracledb.getPool('J1_SGS')._logStats();
            res.end();
        }
    })
}