<form **action="route"**></form>

<form onsubmit="meu método no cliente"></form>

<form class="col-md-12" onsubmit="registerSubmit(this)" method="GET" style="height: 100vh; width:100vw;padding: 10vh 20vw; background-color: rgb(40,40,40)">
        <div class="row">
            <div class="col-md-12">
                <div style="font-size: 10vh;color:white;text-align: left;padding: 5vh 0vw;font-family: 'Major Mono Display', monospace;">Registo:</div>
            </div>
        </div>
        <div class="row" style="padding: 2vh 2vw">
            <div class="col-md-2 text-left badge badge-info" style="font-size: 1em">Nome:</div>
            <div class="offset-md-1"></div>
            <input class="col-md-2" type="text" name="nome" required pattern="[A-Za-z]+" maxlength="25">
            <div class="offset-md-1"></div>
            <div class="col-md-2 text-left badge badge-info " style="font-size: 1em">Apelido:</div>
            <div class="offset-md-1"></div>
            <input class="col-md-3" type="text" name="apelido" required pattern="[A-Za-z]+" maxlength="25">
        </div>
        <div class="row" style="padding: 2vh 2vw">
            <div class="col-md-2 text-left badge badge-info" style="font-size: 1em">Email:</div>
            <div class="offset-md-1"></div>
            <input class="col-md-9" type="email" name="email" required >
        </div>
        <div class="row" style="padding: 2vh 2vw">
            <div class="col-md-2 text-left badge badge-info" style="font-size: 1em">Username:</div>
            <div class="offset-md-1"></div>
            <input class="col-md-9" type="text" name="user" required pattern="^[a-zA-Z][a-zA-Z0-9-_.]{1,20}$" maxlength="25">
        </div>
        <div class="row" style="padding: 2vh 2vw">
            <div class="col-md-2 text-left badge badge-info" style="font-size: 1em">Password:</div>
            <div class="offset-md-1"></div>
            <input class="col-md-9" type="password" name="password" required pattern="^(?=.*d)(?=.*[a-z])(?=.*[A-Z])(?!.*s).*$" minlength="4" maxlength="20">
        </div>
        <div class="row" style="padding: 2vh 2vw">
            <div class="col-md-3 text-center btn btn-danger">Cancelar</div>
            <div class="offset-md-1"></div>
            <div class="col-md-3 text-center btn btn-warning text-white">Repor</div>
            <div class="offset-md-1"></div>
            <input class="col-md-4 text-center btn btn-success" type="submit" value="Registar">
        </div>
    </form>

function registerSubmit(form){
    geturl('http://127.0.0.1:1337/register.html?nome=' + form.nome + '&apelido=' + form.apelido
    + '&email=' + form.email + '&password=' + form.password + '&user=' + form.user, function(res){
        if (res.responseText === 'user')
            window.alert('username already exists');
        else if (res.responseText === 'email')
            window.alert('email already exists');
        else
            // Eu quero exibir o ficheiro HTML
    })
}

function geturl(url, callback){
    var xmlHttp = new XMLHttpRequest();
    xmlHttp.onreadystatechange = function() {
        if (xmlHttp.readyState == 4 && xmlHttp.status == 200){
            callback(xmlHttp.responseText);
            return ;
        }
    }
    xmlHttp.open('GET', url, true);
    xmlHttp.send();
    return xmlHttp.responseText;
}

app.get('/register_submit', function(req, res) {
    var url_parts = url.parse(req.url, true);
    var query = url_parts.query;
    req.nome = query.nome;
    req.apelido = query.apelido;
    req.user = query.user;
    req.password = query.password;
    req.email = query.email;
    register_module.register_submit(req, res);

    /*
    res.writeHead(200, {'Content-Type': 'text/html'});
    fs.readFile('../register.html', function(err, content){
        if (err)
            console.log('ERROR read file');
        res.write(content);
        res.end();
    }); */
});

let mysql = require('mysql');



exports.register_submit = function (req, res){
    let connection = mysql.createConnection({
        host: 'localhost',
        user: 'root',
        password: '**********',
        database: 'website_personal_trainer'
    });

    connection.connect(function(err) {
        if (err) {
          return console.error('error: ' + err.message);
        }

        console.log('Connected to the MySQL server.');


      });

    connection.query('select * from register_data', function(err, result, fields){
        if (err)
            throw err;

        if (check_already_exist_register(result, req)){
            res.end('email');
        } else {
            connection.query('INSERT INTO register_data (first_name, last_name, email, password, username) VALUES (' + req.nome + ',' + req.apelido + ',' +  req.email + ',' + req.password + ',' + req.user + ')',
             function (err, result, fields) {
                if (err)
                    throw err;
                else
                    res.end(alert("register sucessful"));
             })
        }
    });

    connection.end(function(err) {
        if (err) {
          return console.log('error:' + err.message);
        }
        console.log('Close the database connection.');
    });
}

function check_already_exist_register(result, req){
    for (var i in result)
        if (req.user == result[i].username || req.email == result[i].email)
            return true;
    return false;
}