Option Explicit

Dim boolServer As Boolean

Private Sub cmdClient_Click()
    ' Als Client identifizieren und die Möglichkeiten vorgeben
    boolServer = False
    cmdServer.Enabled = False
    cmdClient.Enabled = False
    cmdGo.Enabled = True
End Sub

Private Sub cmdGo_Click()
    Dim I As Integer
    ' Loge ich mich gerade ein ?
    
    If cmdGo.Caption = "Go" Then
        ' Erst mal die Einstellungen eifrieren
        txtNick.Enabled = False
        txtHostIP.Enabled = False
        txtPort.Enabled = False
        cmdGo.Caption = "Stop"
        
        ' Bin ich Server ?
        If boolServer = True Then
            WinSock(0).LocalPort = txtPort.Text
            WinSock(0).Listen
            stBar.SimpleText = "Status: Listening"
        Else
            WinSock(0).RemotePort = txtPort.Text
            WinSock(0).RemoteHost = txtHostIP.Text
            WinSock(0).Connect
            stBar.SimpleText = "Status: Connecting to " &  _
            txtHostIP.Text & ":" & txtPort.Text
        End If
        
        
    ' Ich logge mich gerade aus
    Else
        ' Bin ich Server ?
        If boolServer = True Then
            ' Erst mal alle Verbindungen schließen und unnötige  
' WinSocks entladen
            For I = 1 To WinSock.Count - 1
                WinSock(I).Close
                Unload WinSock(I)
            Next I
        Else
            WinSock(0).Close
        End If
        
        ' Jetzt wieder alles in den Urzustand versetzen
        txtNick.Enabled = True
        txtPort.Enabled = True
        txtHostIP.Enabled = True
        cmdGo.Caption = "Go"
        cmdGo.Enabled = False
        cmdClient.Enabled = True
        cmdServer.Enabled = True
        stBar.SimpleText = "Status: Offline"
    End If
End Sub

Private Sub cmdSend_Click()
Dim strMessage As String
    
    strMessage = "{" & txtNick.Text & "}:" & rtfSend.Text
    
    ' Bin ich Server
    If boolServer = True Then
        SendMessage strMessage
        rftReceive.Text = rftReceive.Text & vbCrLf & strMessage
    Else
        If WinSock(0).State = 7 Then WinSock(0).SendData strMessage
    End If
    
    rtfSend.Text = ""
    
End Sub

Private Sub cmdServer_Click()
    
    ' Erst mal die Buttons ändern
    cmdClient.Enabled = False
    cmdGo.Enabled = True
    cmdServer.Enabled = False
    
    ' Jetzt bin ich Server
    boolServer = True
End Sub

Private Sub WinSock_Close(Index As Integer)
    If Index = "0" Then
        stBar.SimpleText = "Status: Offline"
    Else
        stBar = "Status: Verbunden mit " & WinSock.Count - 1 & " " & _
        "Client(s)."
    End If
End Sub

Private Sub WinSock_Connect(Index As Integer)
    
    ' Jetzt soll man ja wissen, daß man drinnen ist
    stBar.SimpleText = "Status: Connected to " & txtHostIP.Text & ":"  _
    & txtPort.Text
End Sub

Private Sub WinSock_ConnectionRequest(Index As Integer, ByVal  _
requestID As Long)
    ' Ein neues WinSock laden und die Verbindung übernehmen lassen
    Dim intZähler As Integer
    
    intZähler = WinSock.Count
    Load WinSock(intZähler)
    WinSock(intZähler).LocalPort = txtPort.Text
    WinSock(intZähler).Accept requestID
    stBar.SimpleText = "Status: Verbunden mit " & WinSock.Count - 1 &  _
    " Client(s)."
End Sub

Private Sub WinSock_DataArrival(Index As Integer, ByVal bytesTotal As Long)

    Dim strMessage As String

    ' Nachricht holen
    WinSock(Index).GetData strMessage

    ' Bin ich der Server? Dann weiterleiten
    If boolServer = True Then SendMessage strMessage

    ' Ich mags auch sehen
    rftReceive.Text = rftReceive.Text & vbCrLf & strMessage
End Sub

Private Sub SendMessage(Message As String)
    Dim I As Integer
    
    ' Weiterleiten an die anderen clients
    For I = 1 To WinSock.Count - 1
        
        ' Erst mal schauen ob die Verbindung steht
        If WinSock(I).State = 7 Then WinSock(I).SendData Message
    Next I
End Sub

Private Sub WinSock_Error(Index As Integer, ByVal Number As Integer,  _
Description As String, ByVal Scode As Long, ByVal Source As String,  _
        ByVal HelpFile As String, ByVal HelpContext As Long,  _
        CancelDisplay As Boolean)
    If Index < 0 Then
        WinSock(Index).Close
        Unload WinSock(Index)
        rftReceive.Text = rftReceive.Text & vbCrLf & "{System}: " & _
        "Verbindung zu einem Host abgebrochen."
    Else
        WinSock(Index).Close
        rftReceive.Text = rftReceive.Text & vbCrLf & "{System}: Dich " & _
        "hats gerade gegrillt."
        cmdServer.Enabled = True
        cmdClient.Enabled = True
        cmdGo.Caption = "Go"
        cmdGo.Enabled = False
        stBar.SimpleText = "Status: Offline wegen Verbindungsproblem."
    End If