import java.awt.event.*;
import java.io.*;
import java.net.*;
import java.util.*;
public class Server{
    ServerSocket serverSocket; // 創(chuàng)建服務器端套接字
    private final int SERVER_PORT = 8049; //定義端口號
    public Server(){
        try{
            serverSocket=new ServerSocket(SERVER_PORT); // 啟動服務
            System.out.println("Server started...");
            System.out.println("Server port is:"+SERVER_PORT);
            getIP(); // 得到并顯示服務器端IP
 while(true){ // 監(jiān)聽客戶端的連接請求，并返回客戶端socket
                Socket socket=serverSocket.accept();
                new ServerThread(socket); // 創(chuàng)建一個新線程來處理與該客戶的通訊
            }
        }
        catch(IOException e){
            System.out.println("[ERROR] Cound not start server."+e);
        }
    }
    public void getIP(){  // 得到服務器IP地址并顯示
        try{
            InetAddress localAddress = InetAddress.getLocalHost();
            byte[] ipAddress = localAddress.getAddress();
            System.out.println("ServerIPis:"+(ipAddress[0]&0xff)+"."+ (ipAddress[1]&0xff)+"."+(ipAddress[2]&0xff)+"."+(ipAddress[3]&0xff));
        }
        catch(Exception e){
            System.out.println("[ERROR] Cound not get IP."+e);
        }
    }
    public static void main(String args[]){  // 實例化服務器端程序
        new Server();
    }
}
//接收到客戶端socket發(fā)來的信息后進行解析、處理、轉(zhuǎn)發(fā)。
class ServerThread extends Thread{
    private Socket socket;//定義客戶端套接字
    private BufferedReader in;// 定義輸入流
    private PrintWriter out;// 定義輸出流
    private static Vector onlineUser = new Vector(10,5);
    private static Vector socketUser = new Vector(10,5);
    private String strReceive, strKey;
    private StringTokenizer st;
    private final String USERLIST_FILE = "d:\\user.txt"; //設定存放用戶信息的文件
    public ServerThread(Socket client) throws IOException{
        socket = client;
        in=new BufferedReader(new InputStreamReader(socket.getInputStream()));//客戶端接收
out=new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getoutput.Stream())),true);//客戶端輸出
        this.start();	
    }
    public void run(){
        try{
            while(true){    //從服務器端接收一條信息后拆分、解析，并執(zhí)行相應操作
                strReceive = in.readLine();
                st = new StringTokenizer(strReceive,"|");
                strKey = st.nextToken();
                if(strKey.equals("login")){
                    login();
                }
                else if(strKey.equals("talk")){
                    talk();
                }
                else if(strKey.equals("init")){
                    initClientOnline();
                }
                else if(strKey.equals("reg")){
                    register();
                }
            }
        }
        catch(IOException e){     //用戶關閉客戶端造成此異常，關閉該用戶套接字。
            String leaverUser = closeSocket();
            System.out.println("[SYSTEM] "+leaverUser+" leaver JAVA chat!");
            sendAll("talk|>>>"+leaverUser+" 戀戀不舍的離開了聊天室。");
        }
    }
    private boolean isExistUser(String name){   // 判斷是否有該注冊用戶
        String strRead;
        try{
            FileInputStream inputfile = new FileInputStream(USERLIST_FILE);
            DataInputStream inputdata = new DataInputStream(inputfile);
            while((strRead=inputdata.readLine())!=null){
                StringTokenizer stUser = new StringTokenizer(strRead,"|");
                if(stUser.nextToken().equals(name)){
                    return true;
                }
            }
        }
        catch(FileNotFoundException fn){
            System.out.println("[ERROR] User File has not exist!"+fn);
            out.println("warning|讀寫文件時出錯!");
        }
        catch(IOException ie){
            System.out.println("[ERROR] "+ie);
            out.println("warning|讀寫文件時出錯!");
        }
        return false;
    }
    private boolean isUserLogin(String name,String password){ //判斷用戶的用戶名密碼是否正確
        String strRead;
        try{
            FileInputStream inputfile = new FileInputStream(USERLIST_FILE);
            DataInputStream inputdata=new DataInputStream(inputfile);
            while((strRead=inputdata.readLine())!=null){
                if(strRead.equals(name+"|"+password)){
                    return true;
                }
            }
        }
        catch(FileNotFoundException fn){
            System.out.println("[ERROR] User File has not exist!"+fn);
            out.println("warning|讀寫文件時出錯!");
        }
        catch(IOException ie){
            System.out.println("[ERROR] "+ie);
            out.println("warning|讀寫文件時出錯!");
        }
        return false;
    }
    private void register() throws IOException{    // 用戶注冊
        String name = st.nextToken(); //得到用戶名稱
        String password = st.nextToken().trim();//得到用戶密碼
        if(isExistUser(name)){
            System.out.println("[ERROR] "+name+" Register fail!");
            out.println("warning|該用戶已存在，請改名!");
        }
        else{
            RandomAccessFile userFile=new RandomAccessFile(USERLIST_FILE,"rw");
            userFile.seek(userFile.length()); // 在文件尾部加入新用戶信息
            userFile.writeBytes(name+"|"+password+"\r\n");
            longin(name); //自動登陸聊天室
        }
    }
    private void login() throws IOException{   // 用戶登陸(從登陸框直接登陸)
        String name = st.nextToken(); //得到用戶名稱
        String password = st.nextToken().trim();//得到用戶密碼
        boolean succeed = false;
        System.out.println("[USER LOGIN] "+name+":"+password+":"+socket);
        for(int i=0;i<onlineUser.size();i++){
            if(onlineUser.elementAt(i).equals(name)){
                System.out.println("[ERROR] "+name+" is logined!");
                out.println("warning|"+name+"已經(jīng)登陸聊天室");
            }
        }
        if(isUserLogin(name,password)){ // 判斷用戶名和密碼
            longin(name);
            succeed = true;
        }
        if(!succeed){
            out.println("warning|"+name+"登陸失敗，請檢查您的輸入!");
            System.out.println("[SYSTEM] "+name+" login fail!");
        }        
    }
    private void longin(String name) throws IOException{   // 用戶登陸
        out.println("login|succeed");
        sendAll("online|"+name);
        onlineUser.addElement(name);
        socketUser.addElement(socket);
        sendAll("talk|>>>歡迎 "+name+" 進來與我們一起交談!");
        System.out.println("[SYSTEM] "+name+" login succeed!");
    }
    private void talk() throws IOException{  // 聊天信息處理
        String strTalkInfo = st.nextToken(); //得到聊天內(nèi)容;
        String strSender = st.nextToken();  //得到發(fā)消息人
        String strReceiver = st.nextToken(); //得到接收人
        System.out.println("[TALK_"+strReceiver+"] "+strTalkInfo);
        Socket socketSend;
        PrintWriter outSend;
        // 得到當前時間
        GregorianCalendar calendar = new GregorianCalendar();
        String strTime="("+calendar.get(Calendar.HOUR)+":"+calendar.get(Calendar.MINUTE)+
":"+calendar.get(Calendar.SECOND)+")";
        strTalkInfo +=strTime;
        if(strReceiver.equals("All")){
            sendAll("talk|"+strSender+" 對所有人說："+strTalkInfo);
        }
        else{
            if(strSender.equals(strReceiver)){
                out.println("talk|>>>不能自言自語哦!");
            }
            else{
                for(int i=0;i<onlineUser.size();i++){
                    if(strReceiver.equals(onlineUser.elementAt(i))){
                        socketSend = (Socket)socketUser.elementAt(i);
                        outSend = new PrintWriter(new BufferedWriter(new
OutputStreamWriter(socketSend.getOutputStream())),true);
                        outSend.println("talk|"+strSender+" 對你說："+strTalkInfo);
                    }
                    else if(strSender.equals(onlineUser.elementAt(i))){
                        socketSend = (Socket)socketUser.elementAt(i);
                        outSend = new PrintWriter(new BufferedWriter(new
                                  OutputStreamWriter(socketSend.getOutputStream())),true);
                        outSend.println("talk|你對 "+strReceiver+"說："+strTalkInfo);
                    }
                }
            }
        }
    }
   private void initClientOnline() throws IOException{     // 初始化在線用戶列表
        String strOnline = "online";
        for(int i=0;i<onlineUser.size();i++){
            strOnline += "|"+onlineUser.elementAt(i);
        }
        out.println(strOnline);
    }
    private void sendAll(String strSend){   // 信息群發(fā)
        Socket socketSend;
        PrintWriter outSend;
        try{
            for(int i=0;i<socketUser.size();i++){
                socketSend = (Socket)socketUser.elementAt(i);
                outSend = new PrintWriter(new BufferedWriter(new OutputStreamWriter
(socketSend.getOutputStream())),true);
                outSend.println(strSend);
            }
        }
        catch(IOException e){
            System.out.println("[ERROR] send all fail!");
        }
    }	
    private String closeSocket(){  // 關閉套接字，并將用戶信息從在線列表中刪除
        String strUser = "";
        for(int i=0;i<socketUser.size();i++){
            if(socket.equals((Socket)socketUser.elementAt(i))){
                strUser = onlineUser.elementAt(i).toString();
                socketUser.removeElementAt(i);
                onlineUser.removeElementAt(i);
                sendAll("remove|"+strUser);
            }
        }
        try{
            in.close();
            out.close();
            socket.close();
        }catch(IOException e){
            System.out.println("[ERROR] "+e);
        }
        return strUser;
    }
}