var nodemailer = require('nodemailer'),
    smtpTransport = require('nodemailer-smtp-transport'),
    config = require('../config/config'),
    _ = require('underscore'),
    fs= require("fs"),
    jwt = require('jwt-simple');


var transporter = nodemailer.createTransport(smtpTransport({
    host: config.mailer.host,
    port: config.mailer.port,
    auth: {
        user: config.mailer.auth.user,
        pass: config.mailer.auth.pass
    }
}));

_.templateSettings = {
    interpolate: /\{\{(.+?)\}\}/g
};

var functions = {

    sendMail: function(params){
        console.log("in sendmail function" + Date());

        templatePath = __dirname + '/../templates/' + params.template + '.html';
        fs.readFile( templatePath,  'utf8', function(err, file){
            console.log("completed reading template file"+ Date());
            if(err){
                consolelog("error reading template");
                console.log(err)
            }
            else{
                console.log("underscore compiling template"+ Date());
                var compiled = _.template(file);
                var body = compiled(params.data);
                console.log("compilation done"+ Date());

                var mailOptions = {
                    from: config.mailer.auth.user, // sender address
                    to: params.to, // list of receivers
                    bcc: config.mailer.auth.user,
                    subject: params.subject,
                    html: body
                };

                console.log("sending mail"+ Date());
                // send mail with defined transport object
                transporter.sendMail(mailOptions, function(err, info){
                    console.log("mail sent"+ Date());
                    if(err){
                       console.log("email sending error");
                       console.log(err);
                    }
                });
            }
        });
    },

    sendsms: function(params, callback){

        var client = require('twilio')(config.sms.account, config.sms.token);

        client.messages.create({
            to: params.to,
            from: config.sms.from,
            body: params.body
        }, function(err, message) {
            callback(err, message.sid);
        });
    },

    getToken : function(req){
        return (req.body && req.body.access_token) || (req.query && req.query.access_token) || req.headers['x-access-token'];
    },

    getKey: function(req){
        return (req.body && req.body.x_key) || (req.query && req.query.x_key) || req.headers['x-key'];
    },

    generateToken: function(user){
       return genToken(user);
    },

    decodeToken: function(token){
        var decoded = {}
        try {
            decoded = jwt.decode(token, config.secret);
        }
        catch (err){
            console.log("error while decoding token");
            console.log(err);
            return null;
        }
        return decoded;

    },

    pwResetToken: function(username){

        var expires = expiresIn(1);
        var token = jwt.encode({
            user: username,
            exp: expires
        }, config.secret);

        return token;
    }
};

/** private methods,
 * Method to generate access token
 *
 * @param user
 * @returns {{token: String, expires: *, user: *}}
 */
function genToken(user) {

   var expires = expiresIn(config.tokenExpiry);

   var token = jwt.encode({
      user: _.pick(user, ['_id', 'username', 'role']),
      exp: expires
   }, config.secret);

   return {
      token: token,
      expires: expires,
      user: _.pick(user, ['username', 'role'])
   };
}

function expiresIn(numHours) {
   var dateObj = new Date();
   return dateObj.setHours(dateObj.getHours() + numHours);
}


module.exports = functions;