package org.openslx.satellitedaemon;

import java.math.BigInteger;
import java.security.NoSuchAlgorithmException;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.util.Random;

import org.apache.log4j.BasicConfigurator;
import org.apache.log4j.Logger;
import org.openslx.satellitedaemon.filetransfer.FileDownloadWorker;
import org.openslx.satellitedaemon.filetransfer.FileUploadWorker;

/***********************************************************************************************/
/**
 * Main class for uploading images from the HS-Server to the Satellite Server.
 * 
 */
public class App
{
	private static Logger log = Logger.getLogger( App.class );

	public static void main( String[] args ) throws NoSuchAlgorithmException
	{
		BasicConfigurator.configure();

		int i = 0;
		String arg;
		String organizationName;
		BigInteger modulus, privExp, pubExp;
		String ipAddress;

		// Check if there are arguments available and if they start with "--".
		if ( i < args.length && args[i].startsWith( "--" ) ) {
			// Arguments available, take the first one.
			arg = args[i++];
			if ( arg.equals( "--checkconfig" ) ) {
				if ( checkConfig() ) {
					System.exit( 0 );
				}
				log.error( "Config not valid: existing modulus, private and public exponent no valid key pair." );
				System.exit( 2 );
			} else if ( arg.equals( "--genid" ) ) {
				if ( i < args.length ) {
					organizationName = args[i++];
					if ( genId( organizationName ) ) {
						System.exit( 0 );
					}
					else
						System.exit( 2 );
				} else {
					log.error( "Illegal option: --genid requires <organizationName>" );
					System.exit( 2 );
				}
			} else if ( arg.equals( "--import" ) ) {
				if ( args.length != 5 ) {
					log.error( "Illegal option: '--import' requires 4 arguments, <OrgName> <Modulus> <priv_Exponent> <pub_Exponent>" );
					System.exit( 2 );
				} else {
					organizationName = args[i++];
					modulus = new BigInteger( args[i++] );
					privExp = new BigInteger( args[i++] );
					pubExp = new BigInteger( args[i++] );
					if ( importId( organizationName, modulus, privExp, pubExp ) ) {
						System.exit( 0 );
					} else
						System.exit( 2 );
				}
			} else if ( arg.equals( "--submitkey" ) ) {
				if ( i < args.length ) {
					ipAddress = args[i++];
					if ( submitKey( ipAddress ) )
						System.exit( 0 );
					else
						System.exit( 2 );
				} else {
					log.error( "Illegal option: --submitkey requires <IPADDRESS>" );
					System.exit( 2 );
				}
			} else if ( arg.equals( "--updateaddress" ) ) {
				if ( i < args.length ) {
					ipAddress = args[i++];
					if ( updateAddress( ipAddress ) ) {
						System.exit( 0 );
					} else
						System.exit( 2 );
				} else {
					log.error( "Illegal option: --updateaddress requires <IPADDRESS>" );
					System.exit( 2 );
				}
			} else {
				// no correct option was selected.
				log.error( "Illegal option: given argument(s) not valid." );
				log.info( "\nUsage: java -jar target/satellite-daemon-1.0-SNAPSHOT-jar-with-dependencies.jar [options]\n"
						+ " options:\n"
						+ "   [--checkconfig] or\n"
						+ "   [--genid <ORGANIZANTIONNAME>] or\n"
						+ "   [--import <ORGANIZATIONNAME> <MODULUS> <PRIV_EXP> <PUB_EXP>] or\n"
						+ "   [--submitkey <IPADDRESS>] or\n"
						+ "   [--updateaddress <IPADDRESS>]");
				System.exit( 2 );
			}
		} else if ( args.length == 0 ) {
			// No Option choosed, try to load existing identity.
			if ( !tryLoadIdentity() ) {
				System.exit( 2 );
			}
		}

		if ( !Globals.masterServerSslContextInit() ) {
			log.error( "Problem with initializing the SSLContext" );
			System.exit( 1 );
		}
		// Start Up- and Download.
		Thread uploadWorker = new Thread( new FileUploadWorker() );
		uploadWorker.start();
		Thread downloadWorker = new Thread( new FileDownloadWorker() );
		downloadWorker.start();
	}

	private static boolean checkConfig()
	{
		if ( Identity.getOrganizationName() == null ) {
			log.error( "Checking config failed: no existing organization name." );
			return false;
		}
		RSAPublicKey pub = (RSAPublicKey)Identity.getPublicKey();
		RSAPrivateKey priv = (RSAPrivateKey)Identity.getPrivateKey();
		assert ( pub.getModulus() == priv.getModulus() );
		BigInteger modulus = pub.getModulus();
		return Identity.isValidKeyPair(
				modulus,
				priv.getPrivateExponent(),
				pub.getPublicExponent() );
	}

	private static boolean genId( String organizationName )
	{
		return Identity.generateIdentity( organizationName );
	}

	private static boolean importId( String organizationName, BigInteger modulus, BigInteger privExp, BigInteger pubExp )
	{
		if ( !Identity.isValidKeyPair( modulus, privExp, pubExp ) ) {
			log.error( "Given arguments not valid: given modulus, private and public exponent no valid key pair." );
			return false;
		}
		return Identity.importIdentity( organizationName, modulus, privExp, pubExp );
	}

	private static boolean submitKey( String ipAddress )
	{
		return Identity.submitKey( ipAddress );
	}

	private static boolean updateAddress( String ipAddress )
	{
		return Identity.updateAddress( ipAddress );
	}

	private static boolean tryLoadIdentity()
	{
		return checkConfig();
	}
}