//웹 프레임 웤
var express = require('express');

// 요청 리소스 표현 모듈
var request = require('request');

// api의 데이터포맷이 xml이므로 json으로 파싱할 필요가 있음
var convert = require('xml-js');
const bodyParser = require('body-parser');

// 라인 메신져
const TARGET_URL = 'https://api.line.me/v2/bot/message/reply'
const TOKEN = 'OPv3udmn1UGx+xWZFm80KeZbeGJm63nyt+sTpvBr1Mbc1Y0FAeK4MohQLcWq5yytJ6vnaNgXZfigAEFdbjzs05b4QAU+9r1jcZ05t6QvhWDTRYT0Z+YDMMePXtrQYCT84kmkH0OpJ4smBFwLxrtwtAdB04t89/1O/w1cDnyilFU='

// 공공보건포털_API
const CORONA_URL = 'http://openapi.data.go.kr/openapi/service/rest/Covid19/getCovid19InfStateJson';
const SERVICE_KEY = 'DMUPOq6b%2B%2F1gqfLEXQ6bnhgoTO73BfPprA6HVNcV%2F6vHMGG%2Bgiw%2BPDkPvX1eQ7b9uvl%2B42fxUPkU0W3Si907Lw%3D%3D'

// express 미들웨어 정의
var app = express();
app.use(bodyParser.json());

// 기타 비동기식 오류처리에 쓰일 모듈들
const fs = require('fs'); 
const path = require('path'); 
const HTTPS = require('https');
const { measureMemory } = require('vm');
const domain = "www.oss-chatbot-kwak.tk"
const sslport = 23023;

var date;

// 챗봇으로 입력
app.post('/hook', function (req, res) {

    var eventObj = req.body.events[0];
    var source = eventObj.source;
    var message = eventObj.message;

    // request log
    console.log('======================', new Date() ,'======================');
    console.log('[request]', req.body);
    console.log('[request source] ', eventObj.source);
    console.log('[request message]', eventObj.message);

    // 
    if(message.text == '/코로나' || message.text == '/corona'){
        request.post(
            {
                url: TARGET_URL,
                headers: {
                    'Authorization': `Bearer ${TOKEN}`
                },
                json: {
                    "replyToken":eventObj.replyToken,
                    "messages":[
                        {
                            "type":"text",
                            "text":"확인하고 싶으신 일자를 적어주세요."
                        },
                        {
                            "type":"text",
                            "text":"예시) 20201209"
                        }
                    ]
                }
            },(error, response, body) => {
                console.log(body)
            });
        return;
    }
    else
    {
        date = message.text;
        queryParams = '?' + encodeURIComponent('ServiceKey') + '=' + SERVICE_KEY; /* Service Key*/
        queryParams += '&' + encodeURIComponent('pageNo') + '=' + encodeURIComponent('1'); /* */
        queryParams += '&' + encodeURIComponent('numOfRows') + '=' + encodeURIComponent('4'); /* */
        queryParams += '&' + encodeURIComponent('startCreateDt') + '=' + encodeURIComponent(date);
        queryParams += '&' + encodeURIComponent('endCreateDt') + '=' + encodeURIComponent(date); /* */
        bot_reply(eventObj.replyToken, message);
        res.sendStatus(200);
    }
    
});

function bot_reply(replyToken, message) {
    request({
            url: CORONA_URL + queryParams,
            method: 'GET'
        },(error, response, body) => {
            if(!error && response.statusCode == 200) {
                console.log('Status', response.statusCode);
                console.log('Headers', JSON.stringify(response.headers));
                var xmlToJson = convert.xml2json(response.body, {compact: true, spaces: 4});
                const jsonData = JSON.parse(xmlToJson); // json text -> json object
                console.log('Reponse received', xmlToJson); // json text
                
                var resultMessage = jsonData.response.body.items.item;
                
                request.post(
                    {
                        url: TARGET_URL,
                        headers: {
                            'Authorization': `Bearer ${TOKEN}`
                        },
                        json: {
                            "replyToken":replyToken,
                            "messages":[
                                {
                                    "type":"text",
                                    "text": '선택하신 날짜의 Corona Virus-19 현황은 다음과 같습니다.'

                                },
                                {
                                    "type":"text",
                                    "text": JSON.stringify(resultMessage)
                                }
                            ]
                        }
                    },(error, response, body) => {
                        console.log(body)
                    });
            }
        });
}

// 오류처리
try {
    const option = {
      ca: fs.readFileSync('/etc/letsencrypt/live/' + domain +'/fullchain.pem'),
      key: fs.readFileSync(path.resolve(process.cwd(), '/etc/letsencrypt/live/' + domain +'/privkey.pem'), 'utf8').toString(),
      cert: fs.readFileSync(path.resolve(process.cwd(), '/etc/letsencrypt/live/' + domain +'/cert.pem'), 'utf8').toString(),
    };
  
    HTTPS.createServer(option, app).listen(sslport, () => {
      console.log(`[HTTPS] Server is started on port ${sslport}`);
    });
  } catch (error) {
    console.log('[HTTPS] HTTPS 오류가 발생하였습니다. HTTPS 서버는 실행되지 않습니다.');
    console.log(error);
  }