'use strict'
/**
 * Copyright (c) 2017~2019, OBCon Inc.
 * All rights reserved.
 */

/**
 * @file
 * @copyright 2017~2019, OBCon Inc.
 * @author gye hyun james kim [pnuskgh@gmail.com]
 */

let os = require('os');
let osu = require('node-os-utils')

//--- yum  -y  install  sysstat
//--- yum  -y  install  nmon
class Usage {
    constructor() {
    }

    usageServer(callback) {
        let usage = {
            cpu: {},
            memory: {},
            storage: {},
            network: {},
            process: {}
        }

        usage.cpu     = this._getUsageCpu();
        usage.memory  = this._getUsageMemory();
        usage.network = this._getUsageNetwork();
        usage.process = this._getUsageProcess();

        this._getUsageStorage(function(usageStorage) {
            usage.storage = usageStorage;
            callback(usage);
        });
    }

    //--- usageServer : CPU
    _getUsageCpu() {
        let usage = {
            count: 0,                                       //--- CPU 갯수
            model: '',                                      //--- CPU 모델
            rate: {                                         //--- Type별 cpu 사용률(%)
                user: 0.0,                                  //--- 사용자 사용률
                nice: 0.0,
                sys: 0.0,                                   //--- 시스템 사용률
                idle: 0.0,                                  //--- 여유률
                irq: 0.0
            }
        };

        let data = os.cpus();
        usage.count = data.length;
        if (0 < usage.count) {
            usage.model = data[0].model;
            usage.speed = data[0].speed;

            let total  = 0;
            for (let idx = 0; idx < data.length; idx++) {
                let item = data[idx];

                //--- type : user, nice, sys, idle, irq
                for (let type in item.times) {
                    if (idx == 0) {
                        usage.rate[type] = item.times[type];
                    } else {
                        usage.rate[type] = usage.rate[type] + item.times[type];
                    }
                    total  = total + item.times[type];
                }
            }

            for (let type in data[0].times) {
                usage.rate[type] = this._round(usage.rate[type] / total * 100, 2);
            }
        }
        return usage;
    }

    //--- usageServer : Memory
    _getUsageMemory() {
        let usage = {
            free: 0.0,                                      //--- 여유 메모리(MB)
            used: 0.0,                                      //--- 사용 메모리(MB)
            total: 0.0,                                     //--- 전체 메모리(MB)
            rate: {
                free: 0.0,
                used: 0.0
            }
        };

        // usageServer.memory['used']  = process.memoryUsage();
        usage['free']  = this._round(os.freemem() / 1024 / 1024, 2);
        usage['used']  = this._round((os.totalmem() - os.freemem()) / 1024 / 1024, 2);
        usage['total'] = this._round(os.totalmem() / 1024 / 1024, 2);

        usage.rate = {};
        usage.rate['free'] = this._round(usage['free'] / usage['total'] * 100, 2);
        usage.rate['used'] = this._round(usage['used'] / usage['total'] * 100, 2);

        return usage;
    }
    
    //--- usageServer : Storage
    _getUsageStorage(callback) {
        if (this._isLinux()) {
            osu.drive.info()
            .then(function(info) {
                let usage = {
                    free: parseFloat(info.freeGb),
                    used: parseFloat(info.usedGb),
                    total: this._round(parseFloat(info.freeGb) + parseFloat(info.usedGb), 2),
                    rate: {
                        free: this._round(parseFloat(info.freePercentage), 2),
                        used: this._round(parseFloat(info.usedPercentage), 2)
                    }
                };
                callback(usage);
            }.bind(this));
        } else {
            callback({
                free: 0.0,
                used: 0.0,
                total: 0.0,
                rate: { free: 0.00, used: 0.00 }
            });
        }
    }

    _getUsageNetwork() {
        let usage = {
        };

        osu.netstat.stats()
        .then(info => {
            if (info != 'not supported') {
                console.log(info)
            }
        });
  
        osu.netstat.inOut()
        .then(info => {
            if (info != 'not supported') {
                console.log(info)
            }
        });

        return usage;
    }

    _getUsageProcess() {
        let usage = {
        };
        return usage;
    }

    _getUsageDatabase() {
        let database = 'obcondb';
        let query = [];

        //--- Table별로 사용 용량 계산
        query = [];
        query.push(' SELECT TABLE_SCHEMA "DB Name", ROUND(SUM(DATA_LENGTH + INDEX_LENGTH) / 1024 / 1024, 2) "MB"');
        query.push('  FROM information_schema.TABLES');
        query.push(' GROUP BY TABLE_SCHEMA');
        console.log(query.join(' '));

        //--- Table별로 사용 용량 계산
        query = [];
        query.push('SELECT TABLE_NAME, TABLE_ROWS, round((DATA_LENGTH + INDEX_LENGTH) / 1024 / 1024, 2) "MB"');
        query.push('  FROM information_schema.TABLES');
        query.push(' WHERE table_schema = "' + database + '"');
        query.push(' ORDER BY (DATA_LENGTH + INDEX_LENGTH) DESC');
        console.log(query.join(' '));
    }

    usageService() {
        return {};
    }

    usageSite() {
        return {};
    }


    _isLinux() {
        return (process.env.HOME) ? true:false;
    }

    _round(value, pos) {
        if (pos == 2) {
            return Math.round(value * 100) / 100;
        } else {
            return Math.round(value);
        }
    }
}

module.exports = Usage;

// console.log('Start Usage.js');
// let usage = new Usage();

// usage.usageServer(function(usage) {
//     console.log(usage);
// });