// Ftp.java	ftpプログラム
// このプログラムはftpサーバーと接続してファイル転送をします。
// 使い方：java Ftp サーバーアドレス　例：java Ftp ftp4.broadband.co.jp

import java.net.* ;
import java.io.* ;

public class Ftp
{
	Socket ctrlSocket ;
	public PrintWriter ctrlOutput ;
	public BufferedReader ctrlInput ;
	
	final int CTRLPORT = 21 ;
	//-----------------------------------------------------------------------------------------
	public void openConnection(String host) throws IOException, UnknownHostException
	{
		ctrlSocket = new Socket(host, CTRLPORT) ;
		ctrlOutput = new PrintWriter(ctrlSocket.getOutputStream()) ;
		ctrlInput = new BufferedReader(new InputStreamReader(ctrlSocket.getInputStream())) ;
	}
	//-----------------------------------------------------------------------------------------
	public void closeConnection() throws IOException
	{
		ctrlSocket.close();
	}
	//-----------------------------------------------------------------------------------------
	public void showMenu()
	{
		System.out.println(">Command?") ;
		System.out.print("2 ls") ;
		System.out.print("  3 cd") ;
		System.out.print("  4 get") ;
		System.out.print("  5 put") ;
		System.out.print("  6 ascii") ;
		System.out.print("  7 binary") ;
		System.out.print("  9 quit") ;
	}
	//-----------------------------------------------------------------------------------------
	public String getCommand()
	{
		String buf = "" ;
		BufferedReader Lineread = new BufferedReader(new InputStreamReader(System.in)) ;
		
		while(buf.length() != 1)
		{
			try
			{
				buf = Lineread.readLine() ;
			}
			catch(Exception e)
			{
				e.printStackTrace() ;
				System.exit(1) ;
			}
		}
		return(buf) ;
	}
	//-----------------------------------------------------------------------------------------
	public void doLogin()
	{
		String loginName = "" ;
		String password = "" ;
		BufferedReader Lineread = new BufferedReader(new InputStreamReader(System.in)) ;
		try
		{
			System.out.println("ログイン名を入力してください") ;
			loginName = Lineread.readLine() ;
			ctrlOutput.println("USER " + loginName) ;
			ctrlOutput.flush() ;
			System.out.println("パスワードを入力してください") ;
			password = Lineread.readLine() ;
			ctrlOutput.println("PASS " + password) ;
			ctrlOutput.flush() ;
		}
		catch(Exception e)
		{
			e.printStackTrace() ;
			System.exit(1) ;
		}
	}
	//-----------------------------------------------------------------------------------------
	public void doQuit()
	{
		try
		{
			ctrlOutput.println("QUIT ") ;
			ctrlOutput.flush() ;
		}
		catch(Exception e)
		{
			e.printStackTrace() ;
			System.exit(1) ;
		}
	}
	//-----------------------------------------------------------------------------------------
	public void doCd()
	{
		String dirName = "" ;
		BufferedReader Lineread = new BufferedReader(new InputStreamReader(System.in)) ;
		try
		{
			System.out.println("ディレクトリ名を入力してください") ;dirName = Lineread.readLine() ;
			ctrlOutput.println("CWD " + dirName) ;
			ctrlOutput.flush() ;
		}
		catch(Exception e)
		{
			e.printStackTrace() ;
			System.exit(1) ;
		}
	}
	
	//-----------------------------------------------------------------------------------------
	public void doLs()
	{
		try
		{
			int n ;
			byte[] buff = new byte[1024] ;
			Socket dataSocket = dataConnection("LIST") ;
			BufferedInputStream dataInput = new BufferedInputStream(dataSocket.getInputStream()) ;
			while((n = dataInput.read(buff)) > 0 ) 
			{
				System.out.write(buff, 0, n) ;
			}
			dataSocket.close() ;
		}
		catch(Exception e)
		{
			e.printStackTrace() ;
			System.exit(1) ;
		}
	}
	
	//-----------------------------------------------------------------------------------------
	public Socket dataConnection(String ctrlcmd)
	{
		String cmd = "PORT " ;
		int i ;
		Socket dataSocket = null ;
		try {
			byte[] address = InetAddress.getLocalHost().getAddress() ;
			ServerSocket serverDataSocket = new ServerSocket(0, 1) ;
			for(i = 0 ; i < 4 ; ++i) 
			{
				cmd = cmd + (address[i] & 0xff) + "," ;
			}
			cmd = cmd + (((serverDataSocket.getLocalPort()) /256) & 0xff)
			+ ","
			+ (serverDataSocket.getLocalPort() & 0xff) ;
			ctrlOutput.println(cmd) ;
			ctrlOutput.flush() ;
			ctrlOutput.println(ctrlcmd) ;
			ctrlOutput.flush() ;
			dataSocket = serverDataSocket.accept() ;
			serverDataSocket.close() ;
		}
		catch(Exception e)
		{
			e.printStackTrace() ;
			System.exit(1) ;
		}
		return dataSocket ;
	}
	//-----------------------------------------------------------------------------------------
	public void doAscii()
	{
		try
		{
			ctrlOutput.println("TYPE A") ;
			ctrlOutput.flush() ;
		}
		catch(Exception e)
		{
			e.printStackTrace() ;
			System.exit(1) ;
		}
	}
	//-----------------------------------------------------------------------------------------
	public void doBinary()
	{
		try
		{
			ctrlOutput.println("TYPE I") ;
			ctrlOutput.flush() ;
		}
		catch(Exception e)
		{
			e.printStackTrace();
			System.exit(1) ;
		}
	}
	//-----------------------------------------------------------------------------------------
	public void doGet()
	{
		String fileName = "" ;
		BufferedReader Lineread = new BufferedReader(new InputStreamReader(System.in)) ;
		try
		{
			int n ;
			byte[] buff = new byte[1024] ;
			System.out.println("ファイル名を入力してください") ;
			fileName = Lineread.readLine() ;
			FileOutputStream outfile = new FileOutputStream(fileName) ;
			Socket dataSocket = dataConnection ("RETR " + fileName) ;
			BufferedInputStream dataInput = new BufferedInputStream(dataSocket.getInputStream()) ;
			while((n = dataInput.read(buff)) > 0) 
			{
				outfile.write(buff, 0, n) ;
			}
			dataSocket.close() ;
			outfile.close() ;
		}
		catch(Exception e)
		{
			e.printStackTrace() ;
			System.exit(1) ;
		}
	}

	//-----------------------------------------------------------------------------------------
	public void doPut()
	{
		String fileName = "" ;
		BufferedReader Lineread = new BufferedReader(new InputStreamReader(System.in)) ;
		try
		{
			int n ;
			byte[] buff = new byte[1024] ;
			FileInputStream sendfile = null ;
			
			System.out.println("ファイル名を入力してください") ;
			fileName = Lineread.readLine() ;
			try
			{
				sendfile = new FileInputStream(fileName) ;
			}
			catch(Exception e)
			{
				System.out.println("ファイルがありません") ;
				return ;
			}
			
			Socket dataSocket = dataConnection("STRO " + fileName) ;
			OutputStream outstr = dataSocket.getOutputStream() ;
			while((n = sendfile.read(buff)) > 0 ) 
			{
				outstr.write(buff, 0, n) ;
			}
			dataSocket.close() ;
			sendfile.close() ;
		}
		catch(Exception e)
		{
			e.printStackTrace() ;
			System.exit(1) ;
		}
	}
	//-----------------------------------------------------------------------------------------
	public boolean execCommand(String command)
	{
		boolean cont = true ;
		switch(Integer. parseInt(command))
		{
			case 2 : doLs() ; 	break ;
			case 3 : doCd() ; 	break ;
			case 4 : doGet() ;	break ;
			case 5 : doPut() ;	break ;
			case 6 : doAscii() ;	break ;
			case 7 : doBinary () ;	break ;
			case 9 : doQuit() ;	cont = false ;	break ;
			default : System.out.println("番号を選択して下さい") ;
		}
		return (cont) ;
	}
	//-----------------------------------------------------------------------------------------
	public void main_proc() throws IOException 
	{
		boolean cont = true ;
		try
		{
			doLogin() ;
			while(cont)
			{
				showMenu() ;
				cont = execCommand(getCommand()) ;
			}
		
		}
		catch(Exception e)
		{
			System.err.print(e) ;
			System.exit(1) ;
		}
	}
	//-----------------------------------------------------------------------------------------
	public void getMsgs()
	{
		try
		{
			CtrlListen listener = new CtrlListen(ctrlInput) ;
			Thread listenerthread = new Thread(listener) ;
			listenerthread.start() ;
		}
		catch(Exception e)
		{
			e.printStackTrace() ;
			System.exit(1) ;
		}
	}
	//-----------------------------------------------------------------------------------------
	public static void main(String[] args)
	{
		try
		{
			Ftp f = null ;
			if(args.length< 1)
			{
				System.out.println("usage: java Ftp <host name>") ;
				return ;
			}
			f = new Ftp() ;
			f.openConnection(args[0]) ;
			f.getMsgs() ;
			f.main_proc() ;
			f.closeConnection() ;
			System.exit(0) ;
		}
		catch(Exception e)
		{
			e.printStackTrace() ;
			System.exit(1) ;
		}
	}
}
	//-----------------------------------------------------------------------------------------
class CtrlListen implements Runnable
{
	BufferedReader ctrlInput = null ;
	public CtrlListen(BufferedReader in) 
	{
		ctrlInput = in ;
	}
	public void run()
	{
		while(true)
		{
			try
			{
				System.out.println(ctrlInput.readLine()) ;
			}
			catch(Exception e) 
			{
				e.printStackTrace() ;
				System.exit(1) ;
			}
		}
	}
}