/*
* Authenticates a user by checking if there is a record in the DB
* where the useranme and password match
*/
private bool AuthenticateUser(User user, out User authedUser, NetworkStream stream)
{
bool auth = false;
User found = null;
using (ViaChatEntities db = new ViaChatEntities())
{
var query = from u in db.Users
where u.username == user.username &&
u.password == user.password
select u;
if (query.FirstOrDefault <User>() != null)
{
auth = true;
found = query.FirstOrDefault <User>();
SendResponse(true, "", stream);
}
else
{
SendResponse(false, "No user found with those credentials.", stream);
}
}
authedUser = found;
return(auth);
}
/*
* Saves a message in the database
*/
private bool SaveMessage(Message msg, User user, NetworkStream stream)
{
bool success = true;
byte[] receiveBuffer = new Byte[2];
using (ViaChatEntities db = new ViaChatEntities())
{
msg.user_id = user.id;
db.Messages.Add(msg);
try
{
db.SaveChanges();
SendResponse(true, "", stream);
}
catch (Exception e)
{
success = false;
SendResponse(false, e.ToString(), stream);
Console.WriteLine(e);
}
}
stream.Read(receiveBuffer, 0, receiveBuffer.Length); //Wait for user to receive message confirmation
return(success);
}
private User FindUser(string username)
{
/*
* Returns the user having the corresponding username
*/
using (ViaChatEntities context = new ViaChatEntities())
{
var query = from u in context.Users
where u.username == username
select u;
return(query.FirstOrDefault <User>());
}
}
private void SendMessageHistory(NetworkStream stream, User authedUser)
{
ViaChatEntities context = new ViaChatEntities();
byte[] nbMessages = BitConverter.GetBytes(context.Messages.Count <Message>());
stream.Write(nbMessages, 0, nbMessages.Length); //Send number of messages to be read
foreach (Message message in context.Messages)
{
string body = message.body;
string username = message.User.id != authedUser.id ? message.User.username : "******";
byte[] historyEntry = Encoding.ASCII.GetBytes(username + ": " + body + "\n");
byte[] receiveBuffer = new Byte[2];
stream.Write(historyEntry, 0, historyEntry.Length); //Writes the message body in the stream
//RECEIVE OKAY BEFORE CONTINUING, otherwise the server sends all the messages at once, before the client has time to parse them one by one
stream.Read(receiveBuffer, 0, receiveBuffer.Length);
}
}
/*
* Registers a user in the database
* Returns true if success
*/
private bool RegisterUser(User user, NetworkStream stream)
{
bool success = true;
using (ViaChatEntities db = new ViaChatEntities())
{
db.Users.Add(user);
try
{
db.SaveChanges();
SendResponse(true, "", stream);
}
catch (Exception e)
{
success = false;
SendResponse(false, e.ToString(), stream);
Console.WriteLine(e);
}
}
return(success);
}
