package at.gv.egovernment.moa.spss.util;

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Iterator;
import java.util.List;

import at.gv.egovernment.moa.spss.MOAApplicationException;
import at.gv.egovernment.moa.spss.server.config.ConfigurationException;
import at.gv.egovernment.moa.spss.server.config.ConfigurationProvider;
import at.gv.egovernment.moaspss.logging.LogMsg;
import at.gv.egovernment.moaspss.logging.Logger;

public class ExternalURIVerifier {
	
	public static void verify(String host, int port) throws MOAApplicationException {
		
		
		if (host == null)
			return;
		if (host.equalsIgnoreCase(""))
			return;
		
			try {
				ConfigurationProvider config = ConfigurationProvider.getInstance();
				
				boolean allowExternalUris = config.getAllowExternalUris();
				List blacklist = config.getBlackListedUris();
				List whitelist = config.getWhiteListedUris();
				
				InetAddress hostInetAddress = InetAddress.getByName(host);
				String ip = hostInetAddress.getHostAddress();
				
				
				if (allowExternalUris) {
					// external URIs are allowed - check blacklist
					Iterator it = blacklist.iterator();
					while (it.hasNext()) {
						String[] array = (String[])it.next();
						String bhost = array[0];
						String bport = array[1];
						if (bport == null || port == -1) {
							// check only host
							if (ip.startsWith(bhost)) {
								Logger.debug(new LogMsg("Blacklist check: " + host + " (" + ip + ") blacklisted"));
								throw new MOAApplicationException("4002", new Object[]{host + "(" + ip + ")"});
							}
						}
						else {
							// check host and port
							int iport = new Integer(bport).intValue();
							if (ip.startsWith(bhost) && (iport == port)) {
								Logger.debug(new LogMsg("Blacklist check: " + host + ":" + port + " (" + ip + ":" + port + " blacklisted"));
								throw new MOAApplicationException("4002", new Object[]{host + ":" + port + " (" + ip + ":" + port + ")"});							
							}
								
						}
					}
				}
				else {	
					// external uris are forbidden - check whitelist
					Iterator it = whitelist.iterator();
					boolean allowed = false;
					while (it.hasNext()) {
						String[] array = (String[])it.next();
						String bhost = array[0];
						String bport = array[1];
						if (bport == null || port == -1) {
							// check only host
							if (ip.startsWith(bhost)) {
								Logger.debug(new LogMsg("Whitelist check: " + host + " (" + ip + ") whitelisted"));
								allowed = true;
								//throw new MOAApplicationException("4002", new Object[]{host + "(" + ip + ")"});
							}
						}
						else {
							// check host and port
							int iport = new Integer(bport).intValue();
							if (ip.startsWith(bhost) && (iport == port)) {
								Logger.debug(new LogMsg("Whitelist check: " + host + ":" + port + " (" + ip + ":" + port + " whitelisted"));
								//throw new MOAApplicationException("4002", new Object[]{host + ":" + port + " (" + ip + ":" + port + ")"});
								allowed = true;
							}
								
						}
					}
					
					if (!allowed) {
						if (port != -1) {
							Logger.debug(new LogMsg("No external URIs allowed (" + host + ")"));
							throw new MOAApplicationException("4001", new Object[]{host + "(" + ip + ")"});
						}							
						else {
							Logger.debug(new LogMsg("No external URIs allowed (" + host + ":" + port + ")"));
							throw new MOAApplicationException("4001", new Object[]{host + ":" + port + " (" + ip + ":" + port + ")"});
						}
							
					}
					
				}
				
				Logger.debug(new LogMsg("URI allowed: " + ip + ":" + port));
			  	  
			} catch (ConfigurationException e) {
				throw new MOAApplicationException("config.10", null);
			} catch (UnknownHostException e) {
				throw new MOAApplicationException("4003", new Object[]{host});
			}
			
			
		
	}

}