import javax.swing.*;
import java.awt.*;
import java.net.*;
import java.io.*;
import java.awt.event.*;
public class Client extends JFrame implements Runnable,ActionListener            
{ 	//客戶端程序
	//創建Socket通信端口號常量
    public static final int PORT = 8765;
    
	//創建客戶端界面面板
    JPanel jPanel1 = new JPanel();
    JPanel jPanel2 = new JPanel();
    JPanel jPanel3 = new JPanel();
    JPanel jPanel4 = new JPanel();
    
    //創建布局管理方式
    BorderLayout borderLayout1 = new BorderLayout();
    JScrollPane jScrollPane2 = new JScrollPane();
    FlowLayout flowLayout1 = new FlowLayout();
    GridLayout gridLayout1 = new GridLayout();
    
    //創建客戶端界面中的按鈕
    JButton jButton1 = new JButton();
    JButton jButton2 = new JButton();
    JButton jButton3 = new JButton();
    
    //創建用戶名錄入對話框
    JTextField jTextField1 = new JTextField(); 
    //創建聊天對話顯示區域
    JTextArea jTextArea1 = new JTextArea();
    //創建發言輸入框
    JTextField jTextField2 = new JTextField();
    //創建服務器ip地址輸入框
    JTextField jTextField3 = new JTextField();
    //創建服務器端口號輸入框
    JTextField jTextField4 = new JTextField();
    
    //創建標簽對象
    JLabel jLabel1 = new JLabel();
    JLabel jLabel2 = new JLabel();
    JLabel jLabel3 = new JLabel();
    
    Socket socket;  //聲明套接字對象
    Thread thread;  //聲明線程對象
    
    //聲明客戶器端數據輸入輸出流
    DataInputStream in;
    DataOutputStream out;
    boolean bool=false;
    
    //聲明字符串，name存儲用戶名，chat_txt存儲發言信息，chat_in存儲從服務器接收到的信息
    String name,chat_txt,chat_in; 
    String ip=null; 

    public Client()
    {
    	super("Client");
    	//設置內容面板無布局方式
        getContentPane().setLayout(null);
        
        //初始化客戶端界面中的各個組件，包括位置、大小以及處初始顯示內容
        //初始化輸入框組件
        jTextArea1.setText("");
        jTextField1.setText("用戶名輸入");
        jTextField1.setBounds(new Rectangle(103, 4, 77, 25));
        jTextField2.setText("");
        jTextField2.setBounds(new Rectangle(4, 6, 311, 22));
        jTextField3.setText("");
        jTextField4.setText("8765");
        
        //初始化按鈕組件
        jButton1.setBounds(new Rectangle(210, 4, 89, 25));
        jButton1.setToolTipText("");
        jButton1.setText("進入聊天室");
        jButton1.addActionListener(this);
        jButton2.setBounds(new Rectangle(322, 5, 73, 25));
        jButton2.setText("發送");
        jButton2.addActionListener(this);
        jButton3.setBounds(new Rectangle(302, 5, 97, 24));
        jButton3.setText("退出聊天室");
        jButton3.addActionListener(this);
        
        //初始化面板組件
        jPanel1.setLayout(null);
        jPanel1.setBounds(new Rectangle(0, 0, 400, 35));
        jPanel2.setBounds(new Rectangle(264, 35, 136, 230));
        jPanel2.setLayout(gridLayout1);
        jPanel3.setBounds(new Rectangle(0, 35, 255, 230));
        jPanel3.setLayout(borderLayout1);    
        jPanel4.setBounds(new Rectangle(0, 265, 400, 35));
        jPanel4.setLayout(null);

        //初始化標簽組件
        jLabel1.setText("用戶名");
        jLabel1.setBounds(new Rectangle(46, 5, 109, 23));
        jLabel2.setText("服務器地址");
        jLabel3.setText("端口");

        //添加組件至指定面板中的固定位置
        gridLayout1.setColumns(1);
        gridLayout1.setRows(4);
        this.getContentPane().add(jPanel1, null);
        jPanel4.add(jTextField2);
        jPanel4.add(jButton2);
        jPanel1.add(jTextField1, null);
        jPanel1.add(jLabel1);
        jPanel1.add(jButton1, null);
        jPanel1.add(jButton3);
        this.getContentPane().add(jPanel2, null);
        jPanel2.add(jLabel2);
        jPanel2.add(jTextField3);
        jPanel2.add(jLabel3);
        jPanel2.add(jTextField4);
        this.getContentPane().add(jPanel4, null);
        this.getContentPane().add(jPanel3, null);
        jPanel3.add(jScrollPane2, java.awt.BorderLayout.CENTER);
        jScrollPane2.getViewport().add(jTextArea1);
        
        this.setSize(400,400);
        this.setVisible(true);
    }

    public static void main(String[] args)
    {
        Client client = new Client();
        client.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    public void run()    //客戶端線程啟動后的動作
    {
        while(true)    //循環執行
        {
            try
            {
            	//讀取服務器發送來的數據信息，并顯示在對跨窗口中
               chat_in = in.readUTF();
               jTextArea1.append(chat_in);
            }
            catch(IOException e){}
        }
    }
    
    //界面按鈕的事件處理機制
    public void actionPerformed(ActionEvent e) 
    {
    	if(e.getSource() == jButton1)
    	{
    		name=jTextField1.getText();
    		ip=jTextField3.getText();
    		if(name!="用戶名輸入"&&ip!=null)
    		{
    			try 
    			{
    				//創建Socket對象
    				socket = new Socket(ip, PORT);
    				//創建客戶端數據輸入輸出流，用于對服務器端發送或接收數據
    				in = new DataInputStream(socket.getInputStream());
    				out = new DataOutputStream(socket.getOutputStream());
    			} catch (IOException e1) {System.out.println("can not connect");}
    			thread = new Thread(this);
    			thread.start();
    			bool = true;
    		}
    	}
    	else if(e.getSource() == jButton2)
    	{
            chat_txt=jTextField2.getText();
            if(chat_txt!=null)
            {
            	//發言，向服務器發送發言的信息
                try{out.writeUTF(jTextField1.getText()+"對大家說："+chat_txt+"\n");}
                catch(IOException e2){}
            }
            else
            {
                try{out.writeUTF("請說話");}
                catch(IOException e3){}
            }   		
    	}
    	else if(e.getSource() == jButton3)
    	{
            if(bool==true)
            {
                try 
                {
                    socket.close();
                } catch (IOException e4) {}
            }
            thread.destroy();
            bool=false;
            this.setVisible(false);   		
    	}
    }
}