'use strict';
require('dotenv').config();
const moment = require('moment');
const queryString = require('query-string');

const { OAuthAPI } = require('../../helpers/oauthApi');
const db = require('../../models/index');
const { officeRnDAPIErrors } = require('../../constants/constants');

const updateToken = (token, validUntil) => {
    return new Promise((resolve, reject) => {
        const values = {token, validUntil};
        db.accessToken.update(values, {where:{}})
            .then(([numberOfUpdatedRows]) => {
                if (numberOfUpdatedRows > 0){
                    resolve(true);
                }else{
                    db.accessToken.bulkCreate([{token, validUntil}])
                        .then(() => {
                            resolve(false);
                        })
                        .catch((error) => reject(error));
                }
            })
            .catch((error) => reject(error));
    });
};

const getToken = (returnTokenOnly = false) => {
    return new Promise((resolve, reject) => {
        db.accessToken.findAll()
            .then((results) => {
                if (results && results.length > 0){
                    const token = results[0].getDataValue('token');
                    const validUntil = results[0].getDataValue('validUntil');
                    const validUntilMoment = moment(validUntil);
                    if (validUntilMoment.isBefore(moment())){
                        refreshOauthToken()
                            .then((oauthResult) => {
                                if (returnTokenOnly){
                                    resolve(oauthResult.token);
                                }else{
                                    resolve(oauthResult);
                                }
                            })
                            .catch((error) => reject(error));
                    }else{
                        if (returnTokenOnly){
                            resolve(token);
                        }else {
                            resolve({token, validUntil});
                        }
                    }
                }else{
                    refreshOauthToken()
                        .then((oauthResult) => {
                            if (returnTokenOnly){
                                resolve(oauthResult.token);
                            }else{
                                resolve(oauthResult);
                            }
                        })
                        .catch((error) => reject(error));
                }
            })
            .catch((error) => reject(error));
    });
};

const refreshOauthToken = () => {
    return new Promise((resolve, reject) => {
        const clientID = process.env.ORD_OAUTH_CLIENT_ID;
        const clientSecret = process.env.ORD_OAUTH_CLIENT_SECRET;

        const OAUTHRequestBody = {
            client_id: clientID,
            client_secret: clientSecret,
            grant_type: 'client_credentials',
            scope: 'officernd.api.read officernd.api.write',
        };

        OAuthAPI.post('/', queryString.stringify(OAUTHRequestBody))
            .then((oauthResponse) => {
                const responseData = oauthResponse && oauthResponse.data ? oauthResponse.data : null;
                if (responseData){
                    const { access_token: accessToken, expires_in: expiresIn } = responseData;
                    if (accessToken && expiresIn){
                        const validUntil = moment().add(expiresIn, 'seconds').toISOString();
                        updateToken(accessToken, validUntil)
                            .then(() => resolve({token: accessToken, validUntil}))
                            .catch((error) => reject(error));
                    }else{
                        reject(officeRnDAPIErrors.OAUTH_FAILED);
                    }
                }else{
                    reject(officeRnDAPIErrors.OAUTH_FAILED);
                }
            })
            .catch((error) => {
                console.log('Error obtaining OAUTH token : ', error);
                reject();
            });
    });
};

module.exports = {
    getToken,
    refreshOauthToken,
};