public string JoinGame(JoinRequest joinRequest)
{
lock (sync)
{
string userToken = joinRequest.UserToken;
int timeLimit = joinRequest.TimeLimit;
//A user token is valid if it is non - null and identifies a user. Time must be between 5 and 120.
if (userToken == null || !users.ContainsKey(userToken) || timeLimit < 5 || timeLimit > 120)
{
SetStatus(Forbidden);
return(null);
}
// Check if user is already in pending game.
else if (games[gameID].Player1Token == userToken || games[gameID].Player2Token == userToken)
{
SetStatus(Conflict);
return(null);
}
// If player 1 is taken, user is player 2
if (games[gameID].Player1Token != null && games[gameID].Player2Token == null)
{
string GameID = gameID.ToString();
games[gameID].Player2Token = userToken;
StartPendingGame(timeLimit);
SetStatus(Created);
return(GameID);
}
// if player 2 is taken, user is player 1
else if (games[gameID].Player2Token != null && games[gameID].Player1Token == null)
{
string GameID = gameID.ToString();
games[gameID].Player1Token = userToken;
StartPendingGame(timeLimit);
SetStatus(Created);
return(GameID);
}
// if user is first to enter pending game
else
{
string GameID = gameID.ToString();
games[gameID].Player1Token = userToken;
games[gameID].TimeLimit = timeLimit;
SetStatus(Accepted);
return(GameID);
}
}
}
/// <summary>
/// Attempts to join a game with user userToken and timeLimit
///
/// If UserToken is invalid, TimeLimit is less than 5, or TimeLimit is over 120, responds
/// with status 403 (Forbidden).
///
/// Otherwise, if UserToken is already a player in the pending game, responds with status
/// 409 (Conflict).
///
/// Otherwise, if there is already one player in the pending game, adds UserToken as the
/// second player. The pending game becomes active. The active game's time limit is the integer
/// average of the time limits requested by the two players. Returns the new active game's
/// GameID (which should be the same as the old pending game's GameID). Responds with
/// status 201 (Created).
///
/// Otherwise, adds UserToken as the first player of a new pending game, and the TimeLimit as
/// the pending game's requested time limit. Returns the pending game's GameID. Responds with
/// status 202 (Accepted).
/// </summary>
public GameIDResponse JoinGame(JoinRequest request, out HttpStatusCode status)
{
int timeLimit = request.TimeLimit;
// make sure TimeLimit is within the expected bounds
if (!(timeLimit >= 5 && timeLimit <= 120))
{
status = Forbidden;
return(null);
}
//null checks
if (request is null || request.UserToken is null)
{
status = Forbidden;
return(null);
}
// the UserID that'll be used throughout this method
string userID = request.UserToken.Trim();
// make sure UserToken is within the expected bounds
if (userID == null || userID.Length == 0 || userID.Length > 36)
{
status = Forbidden;
return(null);
}
// open connection to database
using (SqlConnection connection = new SqlConnection(BoggleDB))
{
connection.Open();
// execute all commands within a single transaction
using (SqlTransaction transaction = connection.BeginTransaction())
{
// todo: make sure GameID starts at 1, not 0
// (otherwise, this should be changed, because this might actually end up as 0 when creating a game)
int gameID = -1;
// find out whether there's a pending game
using (SqlCommand command = new SqlCommand("select GameID, Player1, TimeLimit from Games where Player2 is null",
connection, transaction))
{
// the reader that will determine whether there's a pending game, and if so, what its gameID is
using (SqlDataReader reader = command.ExecuteReader())
{
while (reader.Read())
{
gameID = (int)reader["GameID"];
string player1 = (string)reader["Player1"];
// averages the time between player1's requested time and this user's requested time
int player1RequestedTime = (int)reader["TimeLimit"];
timeLimit = (timeLimit + player1RequestedTime) / 2;
// player is already searching for a game
if (player1 == userID)
{
status = Conflict;
reader.Close();
transaction.Commit();
return(null);
}
}
}
}
if (gameID == -1)
{
using (SqlCommand command = new SqlCommand("insert into Games (Player1, TimeLimit) output inserted.GameID values(@Player1, @TimeLimit)", connection, transaction))
{
command.Parameters.AddWithValue("@Player1", userID);
command.Parameters.AddWithValue("@TimeLimit", timeLimit);
SqlParameter outputparam = new SqlParameter("@GameID", SqlDbType.Int)
{
Direction = ParameterDirection.Output
};
command.Parameters.Add(outputparam);
// execute command, and get back the primary key (GameID)
try
{
gameID = (int)command.ExecuteScalar();
}
//If an exception was thrown, a foreign key pair was violated
catch (SqlException)
{
status = Forbidden;
transaction.Commit();
return(null);
}
status = Accepted;
}
}
else
{
using (SqlCommand command = new SqlCommand("update Games set Player2 = @Player2, Board = @Board, TimeLimit = @TimeLimit, StartTime = @StartTime where GameID = @GameID", connection, transaction))
{
command.Parameters.AddWithValue("@Player2", userID);
command.Parameters.AddWithValue("@Board", StaticBoard.GenerateBoggleBoard());
command.Parameters.AddWithValue("@TimeLimit", timeLimit);
command.Parameters.AddWithValue("@StartTime", DateTime.UtcNow);
command.Parameters.AddWithValue("@GameID", gameID);
try
{
if (command.ExecuteNonQuery() != 1)
{
throw new Exception("SQL query failed");
}
}
//If Player2 is not a registered user
catch (SqlException)
{
status = Forbidden;
transaction.Commit();
return(null);
}
status = Created;
}
}
transaction.Commit();
return(new GameIDResponse {
GameID = gameID
});
}
}
}
public gameID Join(JoinRequest Request)
{
if (Request.UserToken == null || Request.TimeLimit < 5 || Request.TimeLimit > 120)
{
SetStatus(Forbidden);
return(null);
}
using (SqlConnection conn = new SqlConnection(BoggleDB))
{
conn.Open();
using (SqlTransaction trans = conn.BeginTransaction())
{
//Checking if UserToken exists in Users table.
using (SqlCommand command = new SqlCommand("select UserID from Users where UserID = @UserID", conn, trans))
{
command.Parameters.AddWithValue("@UserID", Request.UserToken);
using (SqlDataReader reader = command.ExecuteReader())
{
if (!reader.HasRows)
{
SetStatus(Forbidden);
trans.Commit();
return(null);
}
}
}
bool player1 = false;
int oldTime = 0;
//Checking if the UserToken is already in the pending game.
using (SqlCommand command = new SqlCommand("select Player1, TimeLimit from Games where Player1 is not null and Player2 is null", conn, trans))
{
using (SqlDataReader reader = command.ExecuteReader())
{
while (reader.Read())
{
if ((string)reader["Player1"] == Request.UserToken)
{
SetStatus(Conflict);
trans.Commit();
return(null);
}
if ((int?)reader["TimeLimit"] != null)
{
player1 = true;
oldTime = (int)reader["TimeLimit"];
}
}
}
}
gameID ID = new gameID();
if (player1)
{
using (SqlCommand command = new SqlCommand("update Games set Player2 = @UserID, Board = @Board, TimeLimit = @TimeLimit, StartTime = @StartTime output inserted.GameID where Player2 is null", conn, trans))
{
command.Parameters.AddWithValue("@UserID", Request.UserToken);
command.Parameters.AddWithValue("@Board", new BoggleBoard().ToString());
command.Parameters.AddWithValue("@TimeLimit", (Request.TimeLimit + oldTime) / 2);
command.Parameters.AddWithValue("@StartTime", DateTime.Now);
ID.GameID = command.ExecuteScalar().ToString();
SetStatus(Created);
trans.Commit();
return(ID);
}
}
else
{
using (SqlCommand command = new SqlCommand("insert into Games (Player1, TimeLimit) output inserted.GameID values (@UserID, @TimeLimit)", conn, trans))
{
command.Parameters.AddWithValue("@UserID", Request.UserToken);
command.Parameters.AddWithValue("@TimeLimit", Request.TimeLimit);
ID.GameID = command.ExecuteScalar().ToString();
SetStatus(Accepted);
trans.Commit();
return(ID);
}
}
}
}
}
