import java.io.*;
import java.security.*;
import java.security.cert.*;

public class SignHandler {
   //private static final char[] ksPasswd = {'a', 'b', 'c', 'd', 'e', 'f'};
   //private static final char[] keyPasswd = {'f', 'e', 'd', 'c', 'b', 'a'};

   public static void main(String[] args) {
      String keystoreName = args[0];
      char[] ksPasswd = args[1].toCharArray();
      String alias = args[2];
      char[] keyPasswd = args[3].toCharArray();
      String data = args[4];
      String certificateName = args[5];
      String signatureName = args[6];
      
      // Läs in privata nyckeln
      KeyStore ks = null;
      PrivateKey privateKey = null;
      try {
         ks = KeyStore.getInstance("JKS");
         BufferedInputStream bis = new BufferedInputStream(new FileInputStream(keystoreName));
         ks.load(bis, ksPasswd);
         privateKey = (PrivateKey) ks.getKey("pierre", keyPasswd);
         System.out.println("DONE LOADING KEY FROM KEYSTORE");
      } catch(KeyStoreException kse) {
         System.out.println("KeyStoreException generated");
      } catch(NoSuchAlgorithmException nsae) {
         System.out.println("NoSuchAlgorithmException generated");
      } catch(CertificateException ce) {
         System.out.println("CertificateException generated");
      } catch(UnrecoverableKeyException uke) {
         System.out.println("UnrecoverableKeyException generated");
      } catch(IOException ioe) {
         System.out.println("IOException generated");
      }

      // Gör en signnatur och verifikations maskin
      Signature signAndVerifyEngine = null;
      try {
         signAndVerifyEngine = Signature.getInstance("SHA1withDSA", "SUN");
         System.out.println("DONE MAKING SIGNATURE/VERIFYING ENGINE");
      } catch(NoSuchAlgorithmException nsae) {
         System.out.println("NoSuchAlgorithmException generated");
      } catch(NoSuchProviderException nspe) {
         System.out.println("NoSuchProviderException generated");
      }

      // Initialisera maskinen
      try {
         signAndVerifyEngine.initSign(privateKey);
      } catch(InvalidKeyException ike) {
         System.out.println("InvalidKeyException generated");
      }

      // Tillför maskinen text-meddelandet
      try {
         BufferedInputStream bis = new BufferedInputStream(new FileInputStream(data));
         byte[] buffer = new byte[1024];
         int length;
         while(bis.available() != 0) {
            length = bis.read(buffer);
            signAndVerifyEngine.update(buffer, 0, length);
         }
         bis.close();
         System.out.println("DONE DELIVERING DATA TO SIGNATURE/VERIFYING ENGINE");
      } catch(SignatureException ike) {
         System.out.println("SignatureException generated");
      } catch(IOException ioe) {
         System.out.println("IOException generated");
      }

      // Signera
      byte[] signature = null;
      try {
         signature = signAndVerifyEngine.sign();
         System.out.println("DONE MESSAGE SIGNED");
      } catch(SignatureException se) {
         System.out.println("SignatureException");
      }      

      // Spara signaturen
      try {
         FileOutputStream fos = new FileOutputStream(signatureName);
         fos.write(signature);
         fos.close();
         System.out.println("DONE SAVING SIGNATURE");
      } catch (IOException ioe) {
         System.out.println("IOException generated");
      }

      // Extrahera certifikatet och spara detta på fil (för att kunna skicka detta till mottagaren)
      try {
         java.security.cert.Certificate cert = ks.getCertificate("pierre");
         byte[] encodedCert = cert.getEncoded();

         FileOutputStream fos = new FileOutputStream(certificateName);
         fos.write(encodedCert);
         fos.close();
         System.out.println("DONE EXTRACTING AND SAVING CERTIFICATE");
      } catch(KeyStoreException kse) {
         System.out.println("KeyStoreException generated");
      } catch(CertificateException ce) {
         System.out.println("CertificateException generated");
      } catch(IOException ioe) {
         System.out.println("IOException generated");
      }
   }
}