routes.js

const express = require('express');
const jwt = require('jsonwebtoken');
const db = require('./db');

const router = express.Router();

const maxPageSize = 100;
const secret = process.env.APISECRET;

router.use((req, res, next) => {
    const token = req.body.token || req.query.token || req.headers['x-access-token'];
    if (token) {
        jwt.verify(token, secret, (err, decoded) => {
            if (err) {
                return res.status(403).send({ success: false, message: 'Failed to authenticate token.' });
            } else {
                req.decoded = decoded;
                next();
            }
        });
    } else {
        return res.status(403).send({
            success: false,
            message: 'No token provided'
        });
    }
});

router.get('/bands', (req, res) => {
    let params = {};
    if (req.query.name)
        params.name = new RegExp(["^", ".*", req.query.name.replace("_", " "), ".*", "$"].join(""), "i");
    if (req.query.country)
        params.country = new RegExp(["^", req.query.country.replace("_", " "), "$"].join(""), "i");
    if (req.query.location)
        params.location = new RegExp(["^", req.query.location.replace("_", " "), "$"].join(""), "i");
    if(req.query.genre)
        params.genre = req.query.genre.replace("_", ".").toLowerCase();

    let limit = parseInt(req.query.limit, 10);
    if (isNaN(limit) || limit > maxPageSize) {
        limit = maxPageSize;
    } else if (limit < 1) {
        limit = 1;
    }
    let page = parseInt(req.query.page, 10);
    if (isNaN(page) || page < 1) {
        page = 1;
    }

    db.get().collection("bands").find(params).skip((page - 1) * limit).limit(limit).sort({ name: 1 }).toArray((err, result) => {
        if (!err) {
            let resp;
            if (req.query.name) {
                let bestMatch = [];
                let others = [];
                let rg = new RegExp(["^", req.query.name.replace("_", " "), ".*", "$"].join(""), "i");
                result.forEach(function (b) {
                    if (b.name.match(rg)) {
                        bestMatch.push(b);
                    } else {
                        others.push(b);
                    }
                });
                resp = { "data": bestMatch.concat(others) };
            }
            else {
                resp = { "data": result };
            }
            res.status(200).send(resp);
        } else {
            res.status(500).send(err);
        }
    });
});

router.get('/countries', (req, res) => {
    if (!req.query.genre) {
        res.status(500).send({ "message": "Pass a genre name as query parameter" });
    } else {
        let genre = req.query.genre.replace("_", ".").toLowerCase();
        db.get().collection(genre).distinct(
            "country",
            {}, // query object
            (function (err, docs) {
                if (err) {
                    res.status(500).send(err);
                }
                if (docs) {
                    res.status(200).send(docs.sort());
                }
            })
        );
    }
});

module.exports = router;