unit main;

interface

uses
 Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
 Menus, StdCtrls, Buttons, ScktComp, ExtCtrls, ComCtrls;

type
 TChatForm = class(TForm)
 MainMenu1: TMainMenu;
 File1: TMenuItem;
 Exit1: TMenuItem;
 FileConnectItem: TMenuItem;
 FileListenItem: TMenuItem;
 StatusBar1: TStatusBar;
 Bevel1: TBevel;
 Panel1: TPanel;
 Memo1: TMemo;
 Memo2: TMemo;
 N1: TMenuItem;
 SpeedButton1: TSpeedButton;
 Disconnect1: TMenuItem;
 ServerSocket: TServerSocket;
 ClientSocket: TClientSocket;
 procedure FileListenItemClick(Sender: TObject);
 procedure FileConnectItemClick(Sender: TObject);
 procedure Exit1Click(Sender: TObject);
 procedure Memo1KeyDown(Sender: TObject; var Key: Word;
 Shift: TShiftState);
 procedure FormCreate(Sender: TObject);
 procedure ServerSocketError(Sender: TObject; Number: Smallint;
 var Description: string; Scode: Integer; const Source,
 HelpFile: string; HelpContext: Integer; var CancelDisplay: Wordbool);
 procedure Disconnect1Click(Sender: TObject);
 procedure ClientSocketConnect(Sender: TObject;
 Socket: TCustomWinSocket);
 procedure ClientSocketRead(Sender: TObject; Socket: TCustomWinSocket);
 procedure ServerSocketClientRead(Sender: TObject;
 Socket: TCustomWinSocket);
 procedure ServerSocketAccept(Sender: TObject;
 Socket: TCustomWinSocket);
 procedure ServerSocketClientConnect(Sender: TObject;
 Socket: TCustomWinSocket);
 procedure ClientSocketDisconnect(Sender: TObject;
 Socket: TCustomWinSocket);
 procedure ClientSocketError(Sender: TObject; Socket: TCustomWinSocket;
 ErrorEvent: TErrorEvent; var ErrorCode: Integer);
 procedure ServerSocketClientDisconnect(Sender: TObject;
 Socket: TCustomWinSocket);
 protected
 IsServer: Boolean;
 end;

var
 ChatForm: TChatForm;
 Server: string;

implementation

{$R *.DFM}

procedure TChatForm.FileListenItemClick(Sender: TObject);
begin
 FileListenItem.Checked := not FileListenItem.Checked;
 if FileListenItem.Checked then
 begin
 ClientSocket.Active := False;
 ServerSocket.Active := True;
 Statusbar1.Panels[0].Text := 'Listening...';
 end
 else
 begin
 if ServerSocket.Active then
 ServerSocket.Active := False;
 Statusbar1.Panels[0].Text := '';
 end;
end;

procedure TChatForm.FileConnectItemClick(Sender: TObject);
begin
 if ClientSocket.Active then
 ClientSocket.Active := False;
 if InputQuery('Computer to connect to', 'Address Name:', Server) then
 if Length(Server) > 0 then
 with ClientSocket do
 begin
 Host := Server;
 Active := True;
 FileListenItem.Checked := False;
 end;
end;

procedure TChatForm.Exit1Click(Sender: TObject);
begin
 ServerSocket.Close;
 ClientSocket.Close;
 Close;
end;

procedure TChatForm.Memo1KeyDown(Sender: TObject; var Key: Word;
 Shift: TShiftState);
begin
 if Key = VK_Return then
 if IsServer then
 ServerSocket.Socket.Connections[0].SendText(Memo1.Lines[Memo1.Lines.Count
 - 1])
 else
 ClientSocket.Socket.SendText(Memo1.Lines[Memo1.Lines.Count - 1]);
end;

procedure TChatForm.FormCreate(Sender: TObject);
begin
 FileListenItemClick(nil);
end;

procedure TChatForm.ServerSocketError(Sender: TObject; Number: Smallint;
 var Description: string; Scode: Integer; const Source, HelpFile: string;
 HelpContext: Integer; var CancelDisplay: Wordbool);
begin
 ShowMessage(Description);
end;

procedure TChatForm.Disconnect1Click(Sender: TObject);
begin
 ClientSocket.Active := False;
 ServerSocket.Active := True;
 Statusbar1.Panels[0].Text := 'Listening...';
end;

procedure TChatForm.ClientSocketConnect(Sender: TObject;
 Socket: TCustomWinSocket);
begin
 Statusbar1.Panels[0].Text := 'Connected to: ' + Socket.RemoteHost;
end;

procedure TChatForm.ClientSocketRead(Sender: TObject;
 Socket: TCustomWinSocket);
begin
 Memo2.Lines.Add(Socket.ReceiveText);
end;

procedure TChatForm.ServerSocketClientRead(Sender: TObject;
 Socket: TCustomWinSocket);
begin
 Memo2.Lines.Add(Socket.ReceiveText);
end;

procedure TChatForm.ServerSocketAccept(Sender: TObject;
 Socket: TCustomWinSocket);
begin
 IsServer := True;
 Statusbar1.Panels[0].Text := 'Connected to: ' + Socket.RemoteAddress;
end;

procedure TChatForm.ServerSocketClientConnect(Sender: TObject;
 Socket: TCustomWinSocket);
begin
 Memo2.Lines.Clear;
end;

procedure TChatForm.ClientSocketDisconnect(Sender: TObject;
 Socket: TCustomWinSocket);
begin
 FileListenItemClick(nil);
end;

procedure TChatForm.ClientSocketError(Sender: TObject;
 Socket: TCustomWinSocket; ErrorEvent: TErrorEvent;
 var ErrorCode: Integer);
begin
 Memo2.Lines.Add('Error connecting to : ' + Server);
 ErrorCode := 0;
end;

procedure TChatForm.ServerSocketClientDisconnect(Sender: TObject;
 Socket: TCustomWinSocket);
begin
 Statusbar1.Panels[0].Text := 'Listening...';
end;

end.