unit u_chat_server;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  ExtCtrls, StdCtrls, WinSock, ScktComp, ComCtrls, OleCtrls, ShellApi,
  IdBaseComponent, IdComponent, IdUDPBase, IdUDPServer, IdSocketHandle,
  IdUDPClient, AppEvnts, bsSkinData, BusinessSkinForm, DB, ADODB,
  bsSkinTabs, bsSkinCtrls, dxExEdtr, dxCntner, dxTL, dxDBCtrl, dxDBGrid,
  dxDBTLCl, dxGrClms;

const
  SERVER_TRAY_MESSAGE = WM_USER + 100;
  
type
  Tfrm_chat_server = class(TForm)
    db: TADOConnection;
    bsBusinessSkinForm1: TbsBusinessSkinForm;
    bsSkinData1: TbsSkinData;
    bsStoredSkin1: TbsStoredSkin;
    UDPServer: TIdUDPServer;
    UDPClient: TIdUDPClient;
    ApplicationEvents: TApplicationEvents;
    bsSkinPageControl1: TbsSkinPageControl;
    bsSkinTabSheet1: TbsSkinTabSheet;
    bsSkinTabSheet2: TbsSkinTabSheet;
    bsSkinPanel1: TbsSkinPanel;
    MemoMsg: TMemo;
    bsSkinPanel2: TbsSkinPanel;
    ServerStatusLabel: TLabel;
    ClientCountLabel: TLabel;
    ListBox1: TListBox;
    t_sys_information: TADOQuery;
    t_sys_information1: TDataSource;
    dxDBGrid1: TdxDBGrid;
    dxDBGrid1Column1: TdxDBGridMaskColumn;
    dxDBGrid1Column2: TdxDBGridMaskColumn;
    dxDBGrid1Column3: TdxDBGridMaskColumn;
    dxDBGrid1Column4: TdxDBGridMaskColumn;
    dxDBGrid1Column5: TdxDBGridDateColumn;
    dxDBGrid1Column6: TdxDBGridMemoColumn;
    procedure FormCreate(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure FormDestroy(Sender: TObject);
    procedure UDPServerUDPRead(Sender: TObject; AData: TStream;
      ABinding: TIdSocketHandle);
    procedure FormCloseQuery(Sender: TObject; var CanClose: Boolean);
    procedure ApplicationEventsMinimize(Sender: TObject);
  private
    FClientDataList: TList;
    FClientID: Integer;
    FClientCount: Integer;
    FConnected: Boolean;
    FReceiveStream: TMemoryStream;
    FSendStream: TMemoryStream;
    ServerTrayIconData : TNotifyIconData;

    procedure ServerTrayMessage(var Message: TMessage); message SERVER_TRAY_MESSAGE;
    procedure ClientConnect(ABinding: TIdSocketHandle);
    procedure ClientReceive(Data: TMemoryStream; ABinding: TIdSocketHandle);
    procedure ClientChat(Data: TMemoryStream; ABinding: TIdSocketHandle);
    procedure ClientLogout(Data: TMemoryStream; ABinding: TIdSocketHandle);
    procedure ShowClientCount;
    { Private declarations }
  public
    { Public declarations }
  end;

var
  frm_chat_server: Tfrm_chat_server;

implementation

uses
  xBASE;
  
{$R *.dfm}

procedure Tfrm_chat_server.ClientChat(Data: TMemoryStream; ABinding: TIdSocketHandle);
var
  AClientData: TxClientData;
  Vi, VCount: Integer;
begin
  Data.Seek(SizeOf(AClientData), soFromCurrent);
  Data.Read(AClientData, SizeOf(AClientData));
  VCount := FClientCount - 1;
  for Vi := 0 to VCount do
  begin
    if AClientData.ClientID = PxClientData(FClientDataList.Items[Vi])^.ClientID then
    begin
      UDPClient.SendBuffer(PxClientData(FClientDataList.Items[Vi])^.IPAddress, UDPClientServerPort, Data.Memory^, Data.Size);
      Break;
    end;
  end;
end;

procedure Tfrm_chat_server.ShowClientCount;
begin
  ClientCountLabel.Caption :=  '在线用户：  ' + IntToStr(FClientCount);
end;

procedure Tfrm_chat_server.ClientConnect(ABinding: TIdSocketHandle);
begin
  FSendStream.Clear;
  MessageID := xMIDConnectS;
  FSendStream.Write(MessageID, SizeOf(MessageID));
  UDPClient.SendBuffer(ABinding.PeerIP, UDPClientServerPort, FSendStream.Memory^, FSendStream.Size);
end;

procedure Tfrm_chat_server.ClientReceive(Data: TMemoryStream;
  ABinding: TIdSocketHandle);
var
  AClientData: PxClientData;
  Vi: Integer;
begin
  New(AClientData);
  Data.Read(AClientData^, SizeOf(TxClientData));
  for Vi := 0 to FClientCount - 1 do
    if AClientData^.IPAddress = PxClientData(FClientDataList.Items[Vi])^.IPAddress then Exit;

  Inc(FClientCount);
  AClientData^.ClientID := FClientID;
  Inc(FClientID);
  FClientDataList.Add(AClientData);

  FSendStream.Clear;
  MessageID := xMIDClientData;
  FSendStream.Write(MessageID, SizeOf(MessageID));
  FSendStream.Write(AClientData^, SizeOf(TxClientData));
  for Vi := 0 to FClientCount - 2 do
    UDPClient.SendBuffer((PxClientData(FClientDataList.Items[Vi])^.IPAddress), UDPClientServerPort, FSendStream.Memory^, FSendStream.Size);

  FSendStream.Clear;
  MessageID := xMIDClientDataS;
  FSendStream.Write(MessageID, SizeOf(MessageID));
  FSendStream.Write(FClientCount, SizeOf(FClientCount));
  for Vi := 0 to FClientCount - 1 do
    FSendStream.Write((FClientDataList.Items[Vi])^, SizeOf(TxClientData));
  UDPClient.SendBuffer(ABinding.PeerIP, UDPClientServerPort , FSendStream.Memory^, FSendStream.Size);

  ShowClientCount;
  if MemoMsg.Lines.Count > 1024 then MemoMsg.Clear;
  MemoMsg.Lines.Add(AClientData.NickName + ' 来自于 ' + AClientData.IPAddress + ' 已经登录');
  ListBox1.Items.Add(AClientData.NickName);
end;

procedure Tfrm_chat_server.ClientLogout(Data: TMemoryStream; ABinding: TIdSocketHandle);
var
  Vi, Vj, VCount,i,j: Integer;
  AClientData: TxClientData;
begin
  Data.Read(AClientData, SizeOf(TxClientData));
  VCount := FClientCount - 1;
  for Vi := 0 to VCount do
  begin
    if AClientData.ClientID = PxClientData(FClientDataList.Items[Vi])^.ClientID then
    begin
      FSendStream.Clear;
      MessageID := xMIDClientLogout;
      FSendStream.Write(MessageID, SizeOf(MessageID));
      FSendStream.Write((FClientDataList.Items[Vi])^, SizeOf(TxClientData));
      for Vj := 0 to VCount do
      begin
        if Vj <> Vi then
          UDPClient.SendBuffer((PxClientData(FClientDataList.Items[Vj])^.IPAddress), UDPClientServerPort, FSendStream.Memory^, FSendStream.Size);
      end;
      FClientDataList.Remove(FClientDataList.Items[Vi]);
      Dec(FClientCount);
      ShowClientCount;
      if MemoMsg.Lines.Count > 1024 then MemoMsg.Clear;
      MemoMsg.Lines.Add(AClientData.NickName + ' 来自于 ' + AClientData.IPAddress + ' 已经断开');
      j:=-1;
      for i:=0 to ListBox1.Items.Count-1 do
      begin
        if AClientData.NickName=ListBox1.Items[i] then
        begin
          j:=ListBox1.ItemIndex;
        end;
      end;
      if j<>-1 then
      begin
        ListBox1.Items.Delete(j);
      end;
      Break;
    end;
  end;
end;

procedure Tfrm_chat_server.ServerTrayMessage(var Message: TMessage);
begin
  if Message.Msg = SERVER_TRAY_MESSAGE then
  begin
    case Message.LParam of
      WM_LBUTTONDBLCLK:
      begin
        if IsIconic(Application.Handle) then begin
          ShowWindow(Application.Handle, SW_NORMAL);
          SetForegroundWindow(Application.Handle);
        end;
      end;
    end;
  end;
end;

procedure Tfrm_chat_server.FormCreate(Sender: TObject);
begin
  FClientDataList := TList.Create;
  FClientID := 40000;
  FClientCount := 0;
  FConnected := False;
  FSendStream := TMemoryStream.Create;
  FReceiveStream := TMemoryStream.Create;
  FClientCount := 0;
  FConnected := True;
  ShowClientCount;
  UDPServer.Active := True;
  UDPClientServerPort := 8401;
  UDPServerPort := 8400;
  ServerStatusLabel.Caption := '服务器已经启动';
  { 托盘 }
  ServerTrayIconData.cbSize := SizeOf(ServerTrayIconData);
  ServerTrayIconData.uFlags := NIF_ICON or NIF_TIP or NIF_MESSAGE;
  ServerTrayIconData.uID := UINT(Self);
  ServerTrayIconData.Wnd := Handle;
  ServerTrayIconData.hIcon := Application.Icon.Handle;
  ServerTrayIconData.szTip := '鑫海达系统消息服务器';
  ServerTrayIconData.uCallbackMessage := SERVER_TRAY_MESSAGE;
  Shell_NotifyIcon(NIM_ADD, @ServerTrayIconData);
end;

procedure Tfrm_chat_server.FormClose(Sender: TObject;
  var Action: TCloseAction);
begin
  FSendStream.Clear;
  MessageID := xMIDServerExit;
  FSendStream.Write(MessageID, SizeOf(MessageID));
  UDPClient.SendBuffer(BROADCAST_ADDRESS, UDPClientServerPort, FSendStream.Memory^, FSendStream.Size);
  Shell_NotifyIcon(NIM_DELETE, @ServerTrayIconData);
end;

procedure Tfrm_chat_server.FormDestroy(Sender: TObject);
begin
  FReceiveStream.Free;
  FSendStream.Free;
  FClientDataList.Free;
end;

procedure Tfrm_chat_server.UDPServerUDPRead(Sender: TObject;
  AData: TStream; ABinding: TIdSocketHandle);
begin
  FReceiveStream.Clear;
  FReceiveStream.LoadFromStream(AData);
  FReceiveStream.Read(MessageID, SizeOf(MessageID));
  
  case MessageID of
     xMIDConnect:
     begin
       ClientConnect(ABinding);
     end;
     xMIDClientData:
     begin
       ClientReceive(FReceiveStream, ABinding);
     end;
     xMIDChat:
     begin
       ClientChat(FReceiveStream, ABinding);
     end;
     xMIDClientLogout:
     begin
       ClientLogout(FReceiveStream, ABinding);
     end;
  end;
end;

procedure Tfrm_chat_server.FormCloseQuery(Sender: TObject;
  var CanClose: Boolean);
begin
  if FClientDataList.Count > 0 then
    CanClose:=false;
end;

procedure Tfrm_chat_server.ApplicationEventsMinimize(Sender: TObject);
begin
  ShowWindow(Application.Handle, SW_HIDE);
end;

end.