package com.ice.syslogd;

import com.ice.syslog.SyslogDefs;

import java.lang.*;
import java.io.*;
import java.net.*;
import java.util.*;


public class
SyslogServer extends Thread
	{
	public static final String		RCS_ID = "$Id: SyslogServer.java,v 1.1.1.1 1998/02/22 05:47:54 time Exp $";
	public static final String		RCS_REV = "$Revision: 1.1.1.1 $";
	public static final String		RCS_NAME = "$Name:  $";

	private static final int	IN_BUF_SZ = (8 * 1024);
	private static final int	SYSLOG_PORT = 514;

	private boolean				socketOpen;

	private int					port;

	private DatagramSocket		inSock;
	private DatagramPacket		inGram;

	private byte[]				inBuffer;
	
	private boolean				debugPacketsReceived;
	private boolean				debugMessagesReceived;

	private SyslogConfig		configuration;
	private ConfigEntryVector	configEntries;

	private FeedbackDisplayer	feedback;


	public
	SyslogServer()
		{
		this( SyslogDefs.DEFAULT_PORT );
		}

	public
	SyslogServer( int port )
		{
		super();

		this.port = port;
		this.socketOpen = false;
		this.inBuffer = null;
		this.inGram = null;

		this.debugPacketsReceived = false;
		this.debugMessagesReceived = false;

		this.feedback = null;
		this.configuration = null;
		this.configEntries = null;
		}

	public SyslogConfig
	getConfiguration()
		{
		return this.configuration;
		}

	public void
	setConfiguration( SyslogConfig configuration )
		{
		this.configuration = configuration;
		this.configEntries = configuration.getConfigEntries();
		}

	public void
	startupServices()
		{
		try {
			this.inSock =
				new DatagramSocket( this.port );

			this.inBuffer =
				new byte[ SyslogServer.IN_BUF_SZ ];

			this.socketOpen = true;
			}
		catch ( SocketException ex )
			{
			System.err.println
				( "FATAL could not create input socket on port '"
					+ this.port + "'\n\t" + ex.getMessage() );
			this.stop();
			}
		}

	public void
	shutdownServices()
		{
		if ( this.socketOpen )
			{
			this.inSock.close();
			this.socketOpen = false;
			}
		}

	public void
	finalize()
		{
		this.shutdownServices();
		this.closeAllActions();
		}

	public void
	openAllActions()
		{
		for ( int eIdx = 0
				; eIdx < this.configEntries.size()
					; ++eIdx )
			{
			ConfigEntry entry =
				this.configEntries.entryAt( eIdx );

			if ( entry != null )
				{
				entry.openAction();
				}
			}
		}

	public void
	closeAllActions()
		{
		for ( int eIdx = 0
				; eIdx < this.configEntries.size()
					; ++eIdx )
			{
			ConfigEntry entry =
				this.configEntries.entryAt( eIdx );

			if ( entry != null )
				{
				entry.closeAction();
				}
			}
		}

	public void
	registerActionDisplay( String name, SyslogDisplayInterface display )
		{
		for ( int eIdx = 0
				; eIdx < this.configEntries.size()
					; ++eIdx )
			{
			ConfigEntry entry =
				this.configEntries.entryAt( eIdx );

			if ( entry != null )
				{
				entry.registerActionDisplay( name, display );
				}
			}
		}

	public void
	setFeedbackDisplayer( FeedbackDisplayer feedback )
		{
		this.feedback = feedback;
		}

	public void
	displayFeedback( String message )
		{
		if ( this.feedback != null )
			{
			this.feedback.displayFeedback( message );
			}
		}

	public void
	run()
		{
		int		packetCount = 0;

		this.displayFeedback
			( "Establishing communications..." );

		this.startupServices();

		this.displayFeedback
			( "Opening all configuration entries..." );

		this.openAllActions();

		this.displayFeedback
			( "Listening for incoming packets..." );

		for ( ; ; )
			{
			try {
				this.inGram =
					new DatagramPacket
						( this.inBuffer, this.inBuffer.length );
			
				this.inSock.receive( this.inGram );
				}
			catch ( IOException ex )
				{
				System.err.println
					( "ERROR reading input socket:\n\t"
						+ ex.getMessage() );
				break;
				}

			String msgBuf =
				new String( this.inGram.getData(), 0,
							this.inGram.getLength() );

			if ( this.debugPacketsReceived )
				System.err.println
					( "[" + this.inGram.getLength()
						+ "] {" + msgBuf + "}" );

			++packetCount;
			this.displayFeedback
				( "Packets received: " + packetCount + "." );

			String hostName =
				this.inGram.getAddress().getHostName();

			if ( hostName == null )
				hostName = "localhost";

			this.processMessage( msgBuf, hostName );
			}

		this.displayFeedback
			( "Closing all configuration entries..." );

		this.closeAllActions();

		this.displayFeedback
			( "Shutting down communications..." );

		this.shutdownServices();
		}

	public void
	processMessage( String message, String hostName )
		{
		int lbIdx = message.indexOf( '<' );
		int rbIdx = message.indexOf( '>' );

		if ( lbIdx < 0 || rbIdx < 0 
				|| lbIdx >= (rbIdx - 1) )
			{
			System.err.println
				( "BAD MSG {" + message + "}" );
			return;
			}
		
		int priCode = 0;
		String priStr =
			message.substring( lbIdx + 1, rbIdx );

		try { priCode = Integer.parseInt( priStr ); }
		catch ( NumberFormatException ex )
			{
			System.err.println
				( "ERROR Bad priority code '" + priStr + "'" );
			return;
			}

		int facility = SyslogDefs.extractFacility( priCode );
		int priority = SyslogDefs.extractPriority( priCode );

		message =
			message.substring
				( rbIdx + 1, (message.length() - 1) );

		//
		// Check to see if msg looks non-standard.
		// In this case, it means that there is not a standard
		// date in the front of the message text.
		//
		boolean stdMsg = true;

		if ( message.length() < 16 )
			{
			stdMsg = false;
			}
		else if (	   message.charAt(3)	!= ' '
					|| message.charAt(6)	!= ' '
					|| message.charAt(9)	!= ':'
					|| message.charAt(12)	!= ':'
					|| message.charAt(15)	!= ' ' )
			{
			stdMsg = false;
			}

		String timestamp;

		if ( ! stdMsg )
			{
			try {
				timestamp =
					TimestampFormat.getInstance().format
						( new Date() );
				}
			catch ( IllegalArgumentException ex )
				{
				System.err.println( "ERROR INTERNAL DATE ERROR!" );
				timestamp = "";
				}
			}
		else
			{
			timestamp = message.substring( 0, 15 );
			message = message.substring( 16 );
			}

		lbIdx = message.indexOf( '[' );
		rbIdx = message.indexOf( ']' );
		int colonIdx = message.indexOf( ':' );
		int spaceIdx = message.indexOf( ' ' );
		
		int		processId = 0;
		String	processName = "";
		String	processIdStr = "";

		if ( lbIdx < (rbIdx - 1)
				&& colonIdx == (rbIdx + 1)
				&& spaceIdx == (colonIdx + 1) )
			{
			processName = message.substring( 0, lbIdx );
			processIdStr = message.substring( lbIdx + 1, rbIdx );
			message = message.substring( colonIdx + 2 );

			try { processId = Integer.parseInt( processIdStr ); }
			catch ( NumberFormatException ex )
				{
				System.err.println
					( "ERROR Bad process id '" + processIdStr + "'" );
				processId = 0;
				}
			}
		else if ( lbIdx < 0 && rbIdx < 0
					&& colonIdx > 0 && spaceIdx == (colonIdx + 1) )
			{
			processName = message.substring( 0, colonIdx );
			message = message.substring( colonIdx + 2 );
			}

		if ( this.debugMessagesReceived )
			System.err.println
				( "[" + facility + ":" + SyslogDefs.getFacilityName(facility)
					+ "] ["
					+ priority + ":" + SyslogDefs.getPriorityName(priority)
					+ "] '"
					+ processName + "' '" + processId + "' "
					+ timestamp + " " + message );

		SyslogMessage logMessage =
			new SyslogMessage(
				facility, priority, timestamp, hostName,
					processName, processId, message );

		for ( int eIdx = 0 ; eIdx < this.configEntries.size() ; ++eIdx )
			{
			ConfigEntry entry =
				this.configEntries.entryAt( eIdx );

			entry.processMessage( logMessage );
			}
		}
	
	}