package com.sequencelogic;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import com.sequencelogic.ByteArr;
import com.sequencelogic.eyeinterface;


// Eye method wrapper class
public class EyeWrapper {
   private static final char[] HexDigits = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };

   private static String digestName = "";
   private static MessageDigest digest;
   private static final int IONU_AES_BLOCK_LEN = 16;
   private static final int IONU_AES_KEY_LEN = 32;

   static {
   }

   public EyeWrapper() {
   }

   private static ByteArr BytesToByteArr (byte[] bytes)
   {
      ByteArr ba = new ByteArr(bytes.length);
      for (int i = 0; i < bytes.length; ++i)
		  ba.setitem(i, bytes[i]);
      return ba;
   }

   private static byte[] ByteArrToBytes (ByteArr ba, int len)
   {
		byte [] bytes = new byte[len];
		for (int i = 0; i < len; ++i)
			bytes[i] = (byte)ba.getitem(i);
		return bytes;
   }
   private static void setdigest (String algo) {
      if (digestName != algo) {
         digestName = algo;
         try {
            digest = MessageDigest.getInstance (digestName);
         }
         catch (NoSuchAlgorithmException e) {
            throw new RuntimeException ("Could not create an instance of " + digestName);
         }
      }
   }

   private static String digest (String string) {
      digest.reset();
      return encodeHex (digest.digest (string.getBytes()));
   }

   public static String md5 (String string) {
      //setdigest ("md5");
      //return digest (string);

      ByteArr mdb = BytesToByteArr (string.getBytes());
      return eyeinterface.ionu_digest_msg ("md5", mdb.cast(), string.length());
   }

   public static String sha1 (String string) {
      setdigest ("sha1");
      return digest (string);
   }

   public static String md5file (String path) {
      return eyeinterface.ionu_digest_file ("md5", path);
   }

   public static byte[] symmetricEncryptBuf (String passphrase, byte[] data) {
      ByteArr d = BytesToByteArr (data);
      ByteArr e = new ByteArr (2048);
      int elen = (int)eyeinterface.ionu_symmetric_encrypt_buffer_pass (passphrase, d.cast(), data.length, e.cast());
      byte[] ebytes = ByteArrToBytes (e, elen);
      d.delete();
      e.delete();
      return ebytes;
   }

   public static byte[] symmetricDecryptBuf (String passphrase, byte[] data) {
      ByteArr d = BytesToByteArr (data);
      ByteArr e = new ByteArr (data.length + 16);
      int elen = (int)eyeinterface.ionu_symmetric_decrypt_buffer_pass (passphrase, d.cast(), data.length, e.cast());
      byte[] ebytes = ByteArrToBytes (e, elen);
      d.delete();
      e.delete();
      return ebytes;
   }

   public static byte[] asymmetricEncryptBuf (String publicpem, byte[] data) {
      ByteArr d = BytesToByteArr (data);
      ByteArr e = new ByteArr (2048);
      int elen = (int)eyeinterface.ionu_public_key_encrypt (publicpem, d.cast(), data.length, e.cast());
      byte[] ebytes = ByteArrToBytes (e, elen);
      d.delete();
      e.delete();
      return ebytes;
   }

   public static byte[] asymmetricDecryptBuf (String privatepem, byte[] data) {
      ByteArr d = BytesToByteArr (data);
      ByteArr e = new ByteArr (2048);
      int elen = (int)eyeinterface.ionu_private_key_decrypt (privatepem, d.cast(), data.length, e.cast());
      byte[] ebytes = ByteArrToBytes (e, elen);
      d.delete();
      e.delete();
      return ebytes;
   }

   public static byte[] asymmetricSignBuf (String privatepem, byte[] data) {
      ByteArr d = BytesToByteArr (data);
      ByteArr e = new ByteArr (2048);
      int elen = (int)eyeinterface.ionu_private_key_encrypt (privatepem, d.cast(), data.length, e.cast());
      byte[] ebytes = ByteArrToBytes (e, elen);
      d.delete();
      e.delete();
      return ebytes;
   }

   public static byte[] asymmetricVerifyBuf (String publicpem, byte[] data) {
      ByteArr d = BytesToByteArr (data);
      ByteArr e = new ByteArr (2048);
      int elen = (int)eyeinterface.ionu_public_key_decrypt (publicpem, d.cast(), data.length, e.cast());
      byte[] ebytes = ByteArrToBytes (e, elen);
      d.delete();
      e.delete();
      return ebytes;
   }


   // Encode the digest as a hex encoded string
   private static String encodeHex(byte[] data) {
      int length = data.length;
      char[] out = new char[length << 1];
      for (int i = 0, j = 0; i < length; i++) {
         out[j++] = HexDigits[(0xF0 & data[i]) >>> 4];
         out[j++] = HexDigits[0x0F & data[i]];
      }
      return new String (out);
   }

}