package org.openslx.satellitedaemon;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.security.KeyFactory;
import java.security.KeyManagementException;
import java.security.KeyStore;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.cert.CertificateException;
import java.util.Properties;

import javax.net.ssl.SSLContext;
import javax.net.ssl.TrustManager;
import javax.net.ssl.TrustManagerFactory;

import org.apache.log4j.Logger;
import org.openslx.satellitedaemon.util.Util;

public class Globals
{
	private static Logger log = Logger.getLogger( Globals.class );
	private static final Properties properties = new Properties();
	private static SSLContext context = null;

	public static final int BLOCKSIZE = 16 * 1024 * 1024; // 16 MB blocksize

	/***********************************************************************************************/
	/**
	 * A call of Globals.getXXXXXX() returns the corresponding entry in config/global.properties
	 */

	// * Properties *//

	public static String getMasterserverHost()
	{
		return properties.getProperty( "MASTERSERVER_HOST" );
	}

	public static String getTruststorePath()
	{
		return properties.getProperty( "TRUSTSTORE_PATH" );
	}

	public static String getImageFolder()
	{
		return properties.getProperty( "IMAGE_FOLDER" );
	}

	// Integers //

	public static int getThriftPort()
	{
		return tryToParseInt( properties.getProperty( "THRIFT_PORT" ) );
	}

	/**
	 * Load properties
	 */
	static {
		InputStreamReader stream = null;
		try {
			// Load all entries of the config file into properties
			stream = new InputStreamReader(
					new FileInputStream( "config/global.properties" ), StandardCharsets.UTF_8 );
			properties.load( stream );
			stream.close();
		} catch ( IOException e ) {
			log.error( "Could not load global.properties. Exiting." );
			System.exit( 2 );
		} finally {
			Util.streamClose( stream );
		}

		Util.notNullOrEmptyFatal( getMasterserverHost(), "Masterserver Host must not be empty!" );
		Util.notNullOrEmptyFatal( getImageFolder(), "Image Folder must not be empty!" );
	}

	/***********************************************************************************************/
	/**
	 * Initialize the ssl context used everywhere for outgoing connections.
	 * 
	 * @return true on success, false on error
	 */
	public static boolean masterServerSslContextInit()
	{
		if ( context != null )
			return true;
		if ( getTruststorePath() == null || getTruststorePath().isEmpty() ) {
			try {
				context = SSLContext.getDefault();
			} catch ( NoSuchAlgorithmException e ) {
				log.error( "could not load system default ssl context.", e );
				return false;
			}
			return true;
		}
		KeyStore keystore;
		try {
			keystore = KeyStore.getInstance( "JKS" );
			keystore.load( new FileInputStream( getTruststorePath() ), null );
			TrustManagerFactory tmf = TrustManagerFactory
					.getInstance( TrustManagerFactory.getDefaultAlgorithm() );
			tmf.init( keystore );
			context = SSLContext.getInstance( "SSLv3" );
			TrustManager[] trustManagers = tmf.getTrustManagers();
			context.init( null, trustManagers, null );
		} catch ( FileNotFoundException e ) {
			log.error( "Could not find the keystore for the filetransfer. Path was '" +
					getTruststorePath() + "'" );
			return false;
		} catch ( Exception e ) {
			log.error( "Could not initialize SSL context.", e );
			return false;
		}
		return true;
	}

	public static SSLContext getMasterServerSslContext()
	{
		return context;
	}

	/**
	 * Tries to parse an int. Returns 0 on error.
	 * 
	 * @param s
	 *           The strig to parse
	 * @return The parsed int or 0 on error
	 */
	public static int tryToParseInt( String s )
	{
		try {
			return Integer.parseInt( s );
		} catch ( NumberFormatException e ) {
			return 0;
		}
	}
}