var router = require('express').Router(),
    mongoose = require('mongoose'),
    Application = mongoose.model('Application'),
    User = mongoose.model('User');
const auth = require('../auth'),
    mailer = require('@sendgrid/mail');

mailer.setApiKey(process.env.SENDGRID_API_KEY);

// Preload application objects on routes with ':application'
router.param('application', function (req, res, next, slug) {
    Application.findOne({ slug: slug })
        .populate('author')
        .then(function (application) {
            if (!application) {
                return res.sendStatus(404);
            }
            req.application = application;
            return next();
        }).catch(next);
});

router.get('/', auth.required, function (req, res, next) {
    let query = {};
    let limit = 25;
    let offset = 0;

    if (typeof req.query.limit !== 'undefined') {
        limit = req.query.limit;
    }
    if (typeof req.query.offset !== 'undefined') {
        offset = req.query.offset;
    }
    if (typeof req.query.apikey !== 'undefined') {
        query.apikey = req.query.apikey;
    }
    if (typeof req.query.maskedkey !== 'undefined') {
        query.maskedkey = req.query.maskedkey;
    }

    Promise.all([
        req.query.author ? User.findOne({ username: req.query.author }) : null
    ]).then(function (author) {
        if (author[0]) {
            query.author = author[0]._id;
        }
        return Promise.all([
            Application.find(query)
                .skip(Number(offset))
                .limit(Number(limit))
                .sort({ createdAt: 'desc' })
                .populate('author')
                .exec(),
            Application.count(query).exec(),
            req.payload ? User.findById(req.payload.id) : null
        ]).then(function (results) {
            let applications = results[0];
            let applicationsCount = results[1];
            let user = results[2];

            return res.json({
                applications: applications.map(function (application) {
                    return application.toJSONFor(user);
                }),
                applicationsCount: applicationsCount
            });
        });
    }).catch(next);
});

router.post('/', auth.required, function (req, res, next) {
    Promise.all([
        User.findById(req.payload.id),
        auth.generateAPIKey()
    ]).then(function (results) {
        let user = results[0];
        let keys = results[1];
        if (!user) {
            return res.sendStatus(401).json({message: "Unauthorized - You are not allowed to access this resource."});
        }
        let application = new Application(req.body.application);
        application.author = user;
        application.apikey = keys.encrypted;
        application.maskedkey = keys.masked;
        return application.save().then(function () {
            let msg = {
                to: user.email,
                from: process.env.SENDGRID_FROM_MAIL,
                subject: `Api-Key ${application.title}`,
                text: `Votre Api-Key: ${keys.key}\nAttention, cette Api-Key doit être conservée et ne sera plus affichée.\n\n${application.title}\n${application.description}`,
                html: `<h2>${application.title}</h2>
                <p>
                Votre Api-Key: ${keys.key}<br />
                <strong>Attention, cette Api-Key doit être conservée et ne sera plus affichée.</strong>
                </p>
                <hr />
                <p>${application.description}</p>`
            };
            mailer.send(msg).then(() => {
                return res.json({ application: application.toJSONFor(user) });
            })
            .catch(err => {
                res.sendStatus(500).json({message: "A SendGrid error occured while sending an email", err: err});
            });
        });
    }).catch(next);
});

// return an application
router.get('/:application', auth.required, function (req, res, next) {
    Promise.all([
        req.payload ? User.findById(req.payload.id) : null,
        req.application.populate('author')
    ]).then(function (results) {
        let user = results[0];
        return res.json({ application: req.application.toJSONFor(user) });
    }).catch(next);
});

router.put('/:application', auth.required, function (req, res, next) {
    User.findById(req.payload.id).then(function (user) {
        if (req.application.author._id.toString() === req.payload.id.toString()) {
            if (typeof req.body.application.title !== 'undefined') {
                req.application.title = req.body.application.title;
            }
            if (typeof req.body.application.description !== 'undefined') {
                req.application.description = req.body.application.description;
            }
            if (typeof req.body.application.apikey !== 'undefined') {
                req.application.apikey = req.body.application.apikey;
            }
            if (typeof req.body.application.maskedkey !== 'undefined') {
                req.application.maskedkey = req.body.application.maskedkey;
            }
            req.application.save().then(function (application) {
                return res.json({ application: application.toJSONFor(user) });
            }).catch(next);
        } else {
            return res.status(403).json({ errors: { "Forbidden": "Vous ne disposez pas des autorisations suffisantes" } });
        }
    });
});

// delete application
router.delete('/:application', auth.required, function (req, res, next) {
    User.findById(req.payload.id).then(function (user) {
        if (!user) {
            return res.status(401).json({ errors: { "Unauthorized": "autentification requise" } });
        }
        if (user.role == 'Admin' || req.application.author._id.toString() === req.payload.id.toString()) {
            return req.application.remove().then(function () {
                return res.sendStatus(204);
            });
        } else {
            return res.status(403).json({ errors: { "Forbidden": "Vous ne disposez pas des autorisations suffisantes" } });
        }
    }).catch(next);
});

module.exports = router;