function wait(i, callback){
    i++;
    return callback(i);
}

bot.on('message_received', function(message, session) {
    var i = 0;
    console.log("FACEBOOK MESSAGE");
    var userid = session.user;
    start_chatbot(message, userid, function(rv) {
        while (i < rv.lenght){
            if (typeof rv[i] === 'string'){
                //console.log(i);
                session.send(rv[i]);
            }
            else{
                //console.log(i);
                request.post(
                    'https://graph.facebook.com/v2.6/me/messages?access_token=EAACHjcJxffsBAFZBmgezxZAYJDYGDwJNnec4aMZBlyftGJMtheApDUmtzKHmGFRDG7kzY81m3WEx4ZCBlN5Ao0UfDiuWUFpHUmMa3RGfX0URQrsefZBDjspnIVLy9zTn0vT9VZCTZA5U1xoRoKyUXGUULbZC1FEFeVuw41u3isZAWeRcqwLV8HnUt',
                    rv[i],
                    function (error, response, body) {
                        if (!error && response.statusCode == 200) {
                            wait(i, function(i){
                                console.log(i);
                            })
                            console.log("reussi")
                            //sleep(4000);
                        }else {
                            console.log("FFFFFFFFFFFFFf");
                            console.log(body);
                            console.log("échec");
                        }
                    }
                    )
            }
            //sleep (1000);
        }

    })
})