/**
 *  This program connects to a web server and gets header infor from it.
 *  Xiannong Meng
 *  03-07-2011
 *  xmeng@bucknell.edu
 */
import java.io.*;
import java.net.*;
import java.util.*;

class HttpHeader {

    public static int PORT = 80;   // default web port

    public static void main(String[] args) throws IOException {

        if (args.length != 1 && args.length != 2 && args.length != 3) {
	    System.out.println(" usage: host [dir port]");
	    System.exit(1);
	}

	if (args.length == 3) { // a port number is supplied
	    PORT = Integer.parseInt(args[2]);
	}
	Socket t   = new Socket(args[0], PORT); // create a socket
        String cmd;

        if (args.length == 1)   // get the root page
            cmd = new String("HEAD / HTTP/1.0\n");
        else   {                // get a specific page
            cmd = new String("HEAD /");
            cmd += args[1].trim();
            cmd += " HTTP/1.0\n";
        }

	cmd += "Host: " + args[0].trim() + "\n";
	cmd += "Connection: Keep-Alive\n";
        cmd += "UserAgent: self-module\n";
        cmd += "Accept: image/gif, image/x-xbitmap, image/jpeg, text/html\n";
        cmd += "\r\n\r\n";

	System.out.println("sending command :");
	System.out.println(cmd);
        // connecting to socket input and output
	BufferedReader is = new BufferedReader
	    (new InputStreamReader
	     (new DataInputStream(t.getInputStream())));

	PrintStream out = new PrintStream(t.getOutputStream());

	out.print(cmd);
	out.flush();

        int count = 0;
	String inBuffer = new String();
	boolean more = true;

	inBuffer = readHttpHeader(is);

	System.out.println("header : " + inBuffer);

    }  // main

    public static String readHttpHeader(BufferedReader fileIn) {

       String inBuffer = "";
       try  {
          String line;
	  do  {
              line = fileIn.readLine();
	      inBuffer += line + "\r\n";
              if (line.length() == 2 && line.compareTo("\n\n") == 0) {
                System.out.println("we hit the break in readAll");
                break;
              }
	  } while (line.length() > 0);
	} catch (IOException ignored) {};
	return inBuffer;
    }
}