/// Last Modified: 9/12/10
/// <summary>
/// Disconnects the node depending on the hosting state.
/// Hosting Enabled: Shuts down the server immediately (synchronously) and notifies the children that the server is no longer available.
/// Hosting Disabled: Disconnects from the host immediately (synchronously).
/// </summary>
/// -----------------------------------------------------
/// PRECONDITIONS:
/// 1) The child node must be connected to the host.
/// -----------------------------------------------------
/// Parameters:
/// -----------------------------------------------------
/// POSTCONDITIONS:
/// 1) The host server will no longer be running and all children will be notified.
/// 2) The child node will no longer be connected to the host.
/// -----------------------------------------------------
/// Return Value:
private void Disconnect()
{
//Clean-up all open chats.
m_Chats.Clear();
//Disconnect the node.
if (m_Node != null)
{
m_Node.Close();
m_Node = null;
}
//Update the interface.
//Both of the host & child terminate their services immediately.
SafelyToggleInterfaceState(false);
//Red-Max is angry and notifies users they are disconnected.
SafelySetIcon(DSChat.Properties.Resources.RedMax);
//Control the connection flag via the disconnect & connect methods as they may be called out
// of their original content.
m_mutexIsConnected.WaitOne(MUTEX_TIMEOUT);
IsConnected = ConnectionState.Disconnected;
m_mutexIsConnected.ReleaseMutex();
//Clear all of the individuals.
UpdateRegisteredUsersListBox(null, ListViewArgumentType.RemoveAllItems, 0);
}
/// Last Modified: 10/24/10
/// <summary>
/// An event that is triggered when an event occurs on a parent node.
/// </summary>
/// -----------------------------------------------------
/// PRECONDITIONS: NA -- No preconditions exist.
/// -----------------------------------------------------
/// Parameters:
/// <param name="nodeEvent">
/// The node event that has occcurred.
/// </param>
/// <param name="sEntityId">
/// The id or name of the entity that spawned the event.
/// </param>
/// <param name="sData">
/// Associated data with the event.
/// </param>
/// -----------------------------------------------------
/// POSTCONDITIONS: NA -- No postconditions exist.
/// -----------------------------------------------------
/// Return Value:
public void ParentNode_OnNodeEvent(RootNode.NodeEvent nodeEvent, string sEntityId, string sData)
{
switch (nodeEvent)
{
case RootNode.NodeEvent.REGISTERED:
{
UpdateRegisteredUsersListBox(sEntityId, ListViewArgumentType.AddItem, 0);
SetStatusLog("User " + sEntityId + " has joined on " + sData);
}
break;
case RootNode.NodeEvent.UNREGISTERED:
{
UpdateRegisteredUsersListBox(sEntityId, ListViewArgumentType.RemoveItem, 0);
SetStatusLog("User " + sEntityId + " has left.");
}
break;
case RootNode.NodeEvent.ALREADY_REGISTERED:
{
SetStatusLog("User " + sEntityId + " has already joined.");
}
break;
case RootNode.NodeEvent.NETWORK_ERROR:
{
SetStatusLog(sData);
}
break;
case RootNode.NodeEvent.SEVERE_NETWORK_ERRROR:
{
SetStatusLog(sData);
//Need synchronization here.
Disconnect();
}
break;
}
//END OF switch (nodeEvent)...
}
/// Last Modified: 10/24/10
/// <summary>
/// Connect the node depending on the hosting state.
/// Hosting Enabled: Begin running the server.
/// Hosting Disabled: Connects to the host.
/// </summary>
/// -----------------------------------------------------
/// PRECONDITIONS: NA -- No preconditions exist.
/// -----------------------------------------------------
/// Parameters:
/// -----------------------------------------------------
/// POSTCONDITIONS:
/// 1) The host server will be running.
/// 2) The child node will attempt to connect to the server.
/// -----------------------------------------------------
/// Return Value:
private void Connect()
{
try
{
NodeSimpleSecurityModel nssm = null;
if(!String.IsNullOrEmpty(txtPassphrase.Text))
nssm = new NodeSimpleSecurityModel(SimpleCryptography.EncryptionScheme.DES, txtPassphrase.Text);
//The host never generates an asynchronous event and either fails
// or succeeds immediately.
SafelyToggleInterfaceState(true);
//Determine if the node will be a host/parent.
if (m_IsHosting)
{
//Obtain the port to listen on.
int nPort = int.Parse(txtListeningPort.Text);
//Create the parent node and start listening.
ParentNode pn = new ParentNode(nPort, nssm);
pn.NodeEventCallback = ParentNode_OnNodeEvent;
pn.Start();
//Update the hosting status.
lblStatus.Text = "Running...";
m_Node = pn;
//Update the notification icon to reflect the node's name.
cmiNodeType.Text = notificationIcon.Text = "DSChat [Parent]";
//Neutral Max means everything is okay.
SafelySetIcon(DSChat.Properties.Resources.MAX);
IsConnected = ConnectionState.Connected;
}
//This would be a child node.
else
{
//Obtain the port to listen on for responses.
int nListeningPort = int.Parse(txtListeningPort.Text);
//Obtain the server address & port of the parent\host.
int nHostPort = int.Parse(txtHostPort.Text);
IPAddress ipAddy = NodeSocket.GetIP4HostAddresses(txtServer.Text);
//Create the child node and register it with the parent with the
// node name provided.
ChildNode cn = new ChildNode(nListeningPort, nssm);
cn.NodeName = txtName.Text;
cn.NodeEventCallback = ChildNode_OnNodeEvent;
cn.Start(ipAddy, nHostPort);
m_Node = cn;
//Update the notification icon to reflect the node's name.
cmiNodeType.Text = notificationIcon.Text = "DSChat [" + txtName.Text + "]";
//The connection has not been made and synchornization is not required here
// as the thread has not been spun up yet.
IsConnected = ConnectionState.IsConnecting;
SetStatusLabel("Connecting...");
m_connectionWaitingThread = new Thread(ThreadProc_WaitingForConnection);
m_connectionWaitingThread.Start((object)this);
}
}
catch (Exception ex)
{
SetStatusLog(ex.Message);
Disconnect();
}
}
/// Last Modified: 9/18/10
/// <summary>
/// An event that is triggered when an event occurs on a child node.
/// </summary>
/// -----------------------------------------------------
/// PRECONDITIONS: NA -- No preconditions exist.
/// -----------------------------------------------------
/// Parameters:
/// <param name="nodeEvent">
/// The node event that has occcurred.
/// </param>
/// <param name="sEntityId">
/// The id or name of the entity that spawned the event.
/// </param>
/// <param name="sData">
/// Associated data with the event.
/// </param>
/// -----------------------------------------------------
/// POSTCONDITIONS: NA -- No postconditions exist.
/// -----------------------------------------------------
/// Return Value:
public void ChildNode_OnNodeEvent(RootNode.NodeEvent nodeEvent, string sEntityId, string sData)
{
switch (nodeEvent)
{
case RootNode.NodeEvent.REGISTRATION_SUCCESSFUL:
{
//If the string is empty, don't bother.
if (!String.IsNullOrEmpty(sData))
{
//Tokenize the string and update the registered users list box
// with the current list of active users.
string[] sUsersList = sData.Split(new char[] { '~' });
foreach (string s in sUsersList)
UpdateRegisteredUsersListBox(s, ListViewArgumentType.AddItem, 0);
}
SafelyToggleInterfaceState(true);
//Notify the form that a successful connection has been made.
m_mutexIsConnected.WaitOne(MUTEX_TIMEOUT);
IsConnected = ConnectionState.Connected;
m_mutexIsConnected.ReleaseMutex();
SetStatusLabel("Connected");
SetStatusLog("Successfully registered with the host.");
//Neutral Max means everything is okay.
SafelySetIcon(DSChat.Properties.Resources.MAX);
}
break;
case RootNode.NodeEvent.REGISTRATION_FAILURE:
{
Disconnect();
SetStatusLabel("Not connected");
SetStatusLog(sEntityId + " has already registered. Use a different name.");
}
break;
case RootNode.NodeEvent.NODE_ADDED:
{
UpdateRegisteredUsersListBox(sData, ListViewArgumentType.AddItem, 0);
SetStatusLog("User " + sData + " has joined.");
}
break;
case RootNode.NodeEvent.NODE_REMOVED:
{
UpdateRegisteredUsersListBox(sData, ListViewArgumentType.RemoveItem, 0);
SetStatusLog("User " + sData + " has left.");
//Ignore any invalid ChatIntermediaries.
ChatIntermediary ci = null;
if (m_Chats.ContainsKey(sData))
{
ci = m_Chats[sData];
}
else
{
ci = new ChatIntermediary();
m_Chats.Add(sData, ci);
}
ci.WriteToChatLog("User " + sData + " has left.");
}
break;
case RootNode.NodeEvent.INVALID_NODE:
{
SetStatusLog(sData + " is not a valid node.");
}
break;
case RootNode.NodeEvent.PARENT_SHUTDOWN:
{
Disconnect();
SetStatusLabel("Not connected");
SetStatusLog("The server has shutdown.");
}
break;
case RootNode.NodeEvent.NETWORK_ERROR:
{
SetStatusLog(sData);
}
break;
case RootNode.NodeEvent.MESSAGE:
{
//Ignore any invalid ChatIntermediaries.
ChatIntermediary ci = null;
if (m_Chats.ContainsKey(sEntityId))
{
ci = m_Chats[sEntityId];
}
else
{
ci = new ChatIntermediary();
m_Chats.Add(sEntityId, ci);
}
//END OF if (m_Chats.ContainsKey(sEntityId))...
ci.WriteToChatLog(sData);
UpdateRegisteredUsersListBox(sEntityId, ListViewArgumentType.ModifyItem, (ci.IsVisible ? 0 : 1));
SafelySetIcon(DSChat.Properties.Resources.GreenMax);
}
break;
case RootNode.NodeEvent.SEVERE_NETWORK_ERRROR:
{
SetStatusLog(sData);
//Need synchronization here.
Disconnect();
}
break;
}
//END OF switch (nodeEvent)...
}