private void SendDatagram(IPEndPoint remoteEP, UdpState udpState,
string timeStamp, DatagramTypes datagramType, string text)
{
try {
StringBuilder sendMessage = new StringBuilder();
sendMessage.AppendLine();
sendMessage.AppendLine(timeStamp);
sendMessage.AppendLine(localClientVersion);
sendMessage.AppendLine(Enum.GetName(typeof(DatagramTypes), datagramType));
sendMessage.AppendLine(localUserKey);
sendMessage.AppendLine(localAddress.ToString());
sendMessage.AppendLine(localUserName);
int headerLength = sendMessage.Length;
sendMessage.Insert(0, headerLength);
sendMessage.AppendLine(text);
byte[] cipherMessage = Security.EncryptString(sendMessage.ToString());
sendUdpClient.BeginSend(cipherMessage, cipherMessage.Length, remoteEP, SendCallback, udpState);
}
catch (Exception ex) {
ErrorHandler.ShowError(ex);
}
}
private void RemoveQueryFromQueue(string key, DatagramTypes type)
{
try {
// Lock the list for thread safety.
lock (queryQueue) {
List <PendingQuery> remList = new List <PendingQuery>();
foreach (PendingQuery status in queryQueue)
{
if (status.UserKey == key && status.Type == type)
{
remList.Add(status);
}
}
// Remove all items that are common to both lists
queryQueue.RemoveAll(new Predicate <PendingQuery>(delegate(PendingQuery item) {
return(remList.Contains(item));
}));
}
}
catch (Exception ex) {
ErrorHandler.ShowError(ex);
}
}
public PendingQuery(string userKey, DatagramTypes type, string timeStamp, string userName, string text, int retries)
{
UserKey = userKey;
Type = type;
TimeStamp = timeStamp;
UserName = userName;
Text = text;
Retries = retries;
}
/// <summary>
/// Add a query with pending acknowledgement to the query queue.
/// </summary>
/// <param name="key"></param>
/// <param name="text"></param>
private void AddQueryToQueue(string key, DatagramTypes type, string timeStamp, string userName, string text, int retries)
{
try {
// Lock the list for thread safety.
lock (queryQueue) {
queryQueue.Add(new PendingQuery(key, type, timeStamp, userName, text, retries));
}
}
catch (Exception ex) {
ErrorHandler.ShowError(ex);
}
}
private void SendBroadcast(DatagramTypes datagramType, string text)
{
try {
string timeStamp = DateTime.UtcNow.ToBinary().ToString();
IPEndPoint remoteEP = new IPEndPoint(broadcastAddress, portNumber);
if (sendUdpClient == null)
{
sendUdpClient = new UdpClient();
}
UdpState udpState = new UdpState(remoteEP, sendUdpClient);
SendDatagram(remoteEP, udpState, timeStamp, datagramType, text);
}
catch (Exception ex) {
ErrorHandler.ShowError(ex);
}
}
private void SendMessage(DatagramTypes datagramType, string remoteUserKey, string text)
{
try {
string timeStamp = DateTime.UtcNow.ToBinary().ToString();
User remoteUser = GetUser(remoteUserKey);
// If user does not exist in user list, display a failure message.
if (remoteUser == null)
{
if (datagramType == DatagramTypes.Message)
{
AddMessageToQueue(remoteUserKey, MessageTypes.Failed, timeStamp, localUserName, localAddress.ToString(), text);
}
return;
}
string remoteUserName = remoteUser.Name;
IPAddress remoteAddress = IPAddress.Parse(remoteUser.Address);
IPEndPoint remoteEP = new IPEndPoint(remoteAddress, portNumber);
if (sendUdpClient == null)
{
sendUdpClient = new UdpClient();
}
UdpState udpState = new UdpState(remoteEP, sendUdpClient);
switch (datagramType)
{
case DatagramTypes.Message:
AddQueryToQueue(remoteUserKey, DatagramTypes.Message, timeStamp, localUserName, text, 0);
break;
case DatagramTypes.File:
string filePath = text;
string key = System.Guid.NewGuid().ToString();
FileTransferInfo fileInfo = SendFile(key, remoteUserKey, remoteUserName, remoteAddress.ToString(), filePath);
// Send message only if SendFile returned succesfully.
if (fileInfo != null)
{
string fileName = fileInfo.FileName;
string fileSize = fileInfo.FileSize;
text = key + Environment.NewLine + fileName + Environment.NewLine + fileSize;
}
else
{
// Do not send the message.
return;
}
break;
case DatagramTypes.Query:
int retries = int.Parse(text);
AddQueryToQueue(remoteUserKey, DatagramTypes.Query, timeStamp, string.Empty, string.Empty, retries);
break;
case DatagramTypes.UserInfo:
text = userInfo.LogonName + Environment.NewLine + userInfo.MachineName + Environment.NewLine
+ userInfo.IPAddress + Environment.NewLine + userInfo.OSName + Environment.NewLine
+ userInfo.MessengerVersion;
break;
}
SendDatagram(remoteEP, udpState, timeStamp, datagramType, text);
}
catch (Exception ex) {
ErrorHandler.ShowError(ex);
}
}
// Constructor.
public ChatArgs(DatagramTypes datagramType, string key, string message)
{
this.datagramType = datagramType;
this.key = key;
this.message = message;
}