/*
<pre>

 ************************************************************************<br>
* you can copy, use, modify and distribute this code for educational, <br>
* commercial or recreational use. all we ask is that you include <br>
* this copyright notice in the source code you distribute. for <br>
* compiled code, you will need to make accessible this copyright notice<br>
* somewhere in the distribution, and/or via a link on the web.<br>
* there are several reasons for this caveat - the most important being<br>
* that open source is based on one main principle: what you find and use, <br>
* others should also have access to. don't keep it to yourself!<br>
* credit where credit is due! http://www.orgdot.com/javaopensource<br>
* <br>
* <br>
* this software is provided by the author and contributors ``as is'' and<br>
* any express or implied warranties, including, but not limited to, the<br>
* implied warranties of merchantability and fitness for a particular purpose<br>
* are disclaimed.  in no event shall the author or contributors be liable<br>
* for any direct, indirect, incidental, special, exemplary, or consequential<br>
* damages (including, but not limited to, procurement of substitute goods<br>
* or services; loss of use, data, or profits; or business interruption)<br>
* however caused and on any theory of liability, whether in contract, strict<br>
* liability, or tort (including negligence or otherwise) arising in any way<br>
* out of the use of this software, even if advised of the possibility of<br>
* such damage.<br>
* <br>
************************************************************************ */


/*


STICK THIS CODE IN THE BODY OF THE HTML REDIRECT-PAGE.


&lt;script language="javascript">&lt;!--



function replaceSpaces (str)
{
	while (str.indexOf ('+') > -1)
	str = str.substring (0, str.indexOf ('+')) + ' ' + str.substring (str.indexOf ('+') + 1)

	return str;
}

function getSearchString()
{
	str = document.location.search;
	if (str != "") return replaceSpaces (unescape(str.substring (1)));
	else return "";
}

document.writeln (getSearchString());



//-->&lt;/script>;

STICK THIS CODE IN THE FORM

&lt;form action="http://www.your.domain.com/servlet/xendmail" method="post" name="mail_form">
  &lt;input type=hidden name="recipient" value="post@your.domain.com">
  &lt;input type=hidden name="subject" value="some subject">
  &lt;input type=hidden name="redirect" value="http://www.your.domain.com/msg.htm">
  &lt;input type=hidden name="nok_message" value="Your message has not been sent">
  &lt;input type=hidden name="aok_message" value="Your message has been sent">
&lt;/form>


*/
import java.io.IOException;
import java.io.PrintStream;
import java.io.BufferedInputStream;
import java.io.ByteArrayOutputStream;

import java.net.Socket;
import java.net.InetAddress;
import java.net.URLEncoder;

import java.util.Enumeration;
import java.util.Date;

import javax.servlet.ServletException;
import javax.servlet.ServletConfig;

import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;




public class xendmail extends HttpServlet
{
	private final String

		mailserver,
		default_recipient,
		default_sender,
		default_subject,
		default_redirect,
		default_nok_message,
		default_aok_message,
		domains[];

	private final int

		mailport;


	public xendmail ()
	{
		super ();
		mailport = 25;
		mailserver = "your.mailserver.com";

		default_recipient = "some.email@your.domain.com";
		default_sender = "some.email@your.domain.com";//we want a valid sender in case that is not entered
		default_subject = "orgdot automail";
		default_redirect = "http://www.your.domain.com/msg.htm";
		default_nok_message = "the message was sent";
		default_aok_message = "there was an error - did you fill in all the fields?";

		String[] domains_ =
		{
			"http://www.some.domain.com",
			"http://www.some.other.domain.com",
			"http://www.some.more.domains.com"
		};
		domains = domains_;
	}


	public void init
	(
		ServletConfig sc
	)
	throws ServletException
	{
		super.init (sc);
	}


	private boolean okDomain
	(
		HttpServletRequest request
	)
	{
		String referer = request.getHeader ("referer");
		for (int i = 0; i < domains.length; i++) if (referer.indexOf (domains[i]) > -1)
		{
			return true;
		}
		return false;
	}

	private String[] getSortedParams
	(
		Enumeration param_names
	)
	{
		String [] workaround = new String [100];
		int num_params = 0;
		while(param_names.hasMoreElements())
		{
			workaround [num_params] = (String) param_names.nextElement();
			num_params ++;
			if (num_params == 100) break;
		}
		num_params --;
		String [] sorted_params = new String [num_params];
		for (int i = 0; i < num_params; i++)
		sorted_params [i] = workaround [i];
		alphabetSort (sorted_params);
		return sorted_params;

	}



/*
a monstrosity - but I do not have time to sort it better just right now
*/
	private void alphabetSort
	(
		String [] arr
	)
	{
		int len = arr.length;
		int [] ints = new int [len];

		for (int i = 0; i < len; i++)
			for (int j = 0; j < len; j++)
			{
				if (arr[i].compareTo (arr[j]) < 0)
				{
					String rem = arr[j];
					arr [j] = arr [i];
					arr [i] = rem;
				}
			}
	}


	private void sendRedirect
	(
		HttpServletResponse response,
		String page,
		String msg
	)
	throws IOException
	{
		response.sendRedirect (page + "?" + URLEncoder.encode (msg) );
	}

/*
in the flash movie you will of course have a textfield named 'msg'
*/

	private void replyFlash
	(
		HttpServletResponse response,
		String msg
	)
	throws IOException
	{
		response.setContentType("text/html");
 		PrintStream ps = new PrintStream ( response.getOutputStream() );
		ps.print ("msg=" + URLEncoder.encode (msg));
		ps.close();
	}


	private boolean invalidMailEntry (String str)
	{
		return
		(
			str.length()      <   7 ||
			str.indexOf ("@") <   0 ||
			str.indexOf (".") <   0 ||
			str.indexOf (" ") > - 1
		);
	}


	private boolean sendMail
	(
		String mailserver_,
		int mailport_,
		String recipient_,
		String sender_,
		String subject_,
		StringBuffer body_
	)
	{
		if (invalidMailEntry (sender_)) sender_ = default_sender;
		try
		{
			Socket socket = new Socket ( mailserver_, mailport_ );
			BufferedInputStream bis = new BufferedInputStream ( socket.getInputStream() );
			ByteArrayOutputStream baos = new ByteArrayOutputStream ();
			PrintStream ps = new PrintStream ( socket.getOutputStream() );

			if
			(
				readStringLine (bis, baos) &&
				writeStringLine (ps, "HELO " + socket.getLocalAddress().getHostName() + "\r\n") &&

				readStringLine (bis, baos) &&
				writeStringLine (ps, "MAIL FROM: " + sender_ + "\r\n") &&

				readStringLine (bis, baos) &&
				writeStringLine (ps, "RCPT To: " + recipient_ + "\r\n") &&

				readStringLine (bis, baos) &&
				writeStringLine (ps, "DATA\r\n") &&

				readStringLine (bis, baos) &&
				writeStringLine (ps, "Subject: " + subject_ + "\r\n") &&
				writeStringLine (ps, body_.toString() + "\r\n") &&
				writeStringLine (ps, ".\r\n") &&
				writeStringLine (ps, "quit\r\n")

			)
			{
				ps.close ();
				bis.close ();
				socket.close ();
				baos.close ();
			}
			return true;
		}
		catch (Throwable t)
		{
			return false;
		}
	}



    private boolean writeStringLine
    (
		PrintStream ps,
		String str
	)
	throws IOException
	{
		ps.print (str);
		ps.flush();
		return true;
	}

    private boolean readStringLine
    (
		BufferedInputStream in,
		ByteArrayOutputStream baos
	)
	throws IOException
	{
		baos.reset ();
		if (in == null) return false;
		in.mark ( in.available() );
		int i;
		while ( ( i = in.read() ) > - 1)
		{
			if (i == '\n') return true;
			else if (i == '\r')
			{
				if ( (i = in.read()) == '\n' ) return true;
				else if (i == -1 ) return false;
				else
				{
					in.reset ();
					in.skip  ( baos.size () + 1 );
					return true;
				}
			}
			else baos.write (i);
		}
		in.close();
		return true;
	}



	public void service
	(
		HttpServletRequest request,
		HttpServletResponse response
	)
	throws ServletException, IOException
	{
		if ( ! okDomain (request) )
		{
			sendRedirect (response, default_redirect, default_nok_message);
		}

		else
		{
			String recipient = default_recipient;
			String sender    =    default_sender;
			String subject   =   default_subject;
			String redirect  =  default_redirect;

			String nok_message = default_nok_message;
			String aok_message = default_aok_message;

			StringBuffer body = new StringBuffer();

			boolean reply_flash = false;

			body.append ("------------------------------\n");
			body.append ("Orgdot automail:\ndate: ");
			body.append (new Date ());
			body.append ("\nServer: ");
			body.append (getServletConfig().getServletContext().getServerInfo());
			body.append ("\nIP trace on remote machine: ");
			body.append (InetAddress.getByName(request.getRemoteAddr()));
			body.append ("\n------------------------------\n\n\n");
			body.append ("\nPlease note! If the sender's address above is ");
			body.append (default_sender);
			body.append ("\nthen the user filling out the form has not entered anything");
			body.append ("\nin the e-mail field. ");
			body.append (default_sender);
			body.append (" is just to keep\nsendmail happy...");
			body.append ("\n------------------------------\n\n\n");


			String[] sorted_param_names = getSortedParams (request.getParameterNames ());
			for (int j = 0; j < sorted_param_names.length; j++)
			{
				String str = sorted_param_names[j];
				String check;

				String [] param_values = request.getParameterValues (str);

				if ( str.equals ("recipient")  && ( check = param_values [0]) != null )
				{
					recipient = check;
				}
				else if ( str.equals ("sender") && ( check = param_values [0]) != null)
				{
					sender = check;
				}
				else if ( str.equals ("reply_flash") && ( check = param_values [0]) != null )
				{
					reply_flash = check.equals("true");
				}
				else if ( str.equals ("subject") && ( check = param_values [0]) != null )
				{
					subject = check;
				}
				else if ( str.equals ("redirect") && ( check = param_values [0]) != null )
				{
					redirect = check;
				}
				else if ( str.equals ("nok_message") && ( check = param_values [0]) != null )
				{
					nok_message = check;
				}
				else if ( str.equals ("aok_message") && ( check = param_values [0]) != null )
				{
					aok_message = check;
				}
				else for (int i = 0; i < param_values.length; i++)
				{
					body.append (str);
					body.append (":\n");
					body.append (param_values [i]);
					body.append ("\n\n");
				}
			}

			if
			(
				sendMail
				(
					mailserver,
					mailport,
					recipient,
					sender,
					subject,
					body
				)
			)
			{
				if (reply_flash) replyFlash (response, aok_message);
				else sendRedirect (response, redirect, aok_message);
			}
			else
			{
				if (reply_flash) replyFlash (response, nok_message);
				else sendRedirect (response, redirect, nok_message);
			}
		}
	}
}