//var jwt = require('express-jwt');
var { expressjwt: jwt } = require("express-jwt"),
    secret = require('../config').secret,
    crypto = require('crypto');
const { v4 } = require('uuid'),
    passport = require('passport'),
    auths = ['Api-Key', 'Basic', 'Bearer', 'Token'];

function getTokenFromHeader(req) {
    if(req.headers.authorization && auths.indexOf(req.headers.authorization.split(' ')[0]) !== -1) {
        return req.headers.authorization.split(' ')[1];
    }
    return null;
}

const auth = {
    requiredJwt: jwt({
        secret: secret,
        algorithms: ['HS256'],
        requestProperty: 'payload',
        getToken: getTokenFromHeader
    }),
    optional: jwt({
        secret: secret,
        algorithms: ['HS256'],
        requestProperty: 'payload',
        credentialsRequired: false,
        getToken: getTokenFromHeader
    }),
    required: async (req, res, next) => {
        if(req.headers.authorization && req.headers.authorization.split(' ')[0] === process.env.AUTHORIZATION_PREFIX) {
            passport.authenticate('headerapikey', { session: false }, function (err, application, info) {
                if (err) {
                    return next({message: "An authentication error occured.", err: err.message});
                }
                if (!application) {
                    return res.status(401).json({message: "Unauthorized - You are not allowed to access this resource.", err: err, info: info});
                }
                req.application = application;
                req.payload = { id: application.authorId };
                return next();
            })(req, res, next);
        } else {
            return jwt({
                secret: secret,
                algorithms: ['HS256'],
                requestProperty: 'payload',
                getToken: getTokenFromHeader
            })(req, res, next);
        }
    },
    getAuthType: (req) => {
        if(req.headers.authorization && auths.indexOf(req.headers.authorization.split(' ')[0]) !== -1) {
            let value = req.headers.authorization.split(' ')[0];
            return value;
        }
        return null;
    },
    generateAPIKey: () => {
        const key = v4().replace(/-/g, '');
        const maskedKey = `${key.slice(0, 4)}...${key.slice(-4)}`;
        const encryptedKey = crypto.createHmac('sha256', secret).update(key).digest('hex');
        return { key, masked: maskedKey, encrypted: encryptedKey };
    },
    authenticateKey: async (req, res, next) => {
        passport.authenticate('headerapikey', { session: false }, function (err, application, info) {
            if (err) {
                return res.status(err.status || 500).json({message: "An authentication error occured (authenticateKey).", err: err.message});
            }
            if (!application) {
                return res.status(401).json({message: "Unauthorized - You are not allowed to access this resource.", err: err, info: info});
            }
            req.application = application;
            return next();
        })(req, res, next);
    }
};

module.exports = auth;