instagram signed_body

public class RequestUtil
{
  public static String SIGNATURE_KEY_VERSION = "4";
  public static String SIGNATURE_KEY_VERSION_FIELD_NAME = "ig_sig_key_version";
  static String sLastValidAlgorithm = null;

  public static String generateSignature(String paramString)
  {
    String str1 = NativeBridge.getInstagramString("a4d1b77bbb1a4a5ca695ad72c84b77e5");
    String str3;
    StringBuilder localStringBuilder;
    try
    {
      Mac localMac = getValidMac();
      localMac.init(new SecretKeySpec(str1.getBytes("UTF-8"), localMac.getAlgorithm()));
      byte[] arrayOfByte = localMac.doFinal(paramString.getBytes());
      BigInteger localBigInteger = new BigInteger(1, arrayOfByte);
      String str4 = String.format("%0" + (arrayOfByte.length << 1) + "x", new Object[] { localBigInteger });
      str3 = str4;
      return str3;
    }
    catch (Exception localException)
    {
      localStringBuilder = new StringBuilder().append("failed_to_generate_signature: ");
      if (localException.getMessage() == null);
    }
    for (String str2 = localException.getMessage(); ; str2 = localException.getClass().toString())
    {
      NoopUtil.report(str2);
      str3 = null;
      break;
    }
  }

  private static Mac getValidMac()
  {
    if (sLastValidAlgorithm != null);
    while (true)
    {
      try
      {
        Mac localMac2 = Mac.getInstance(sLastValidAlgorithm);
        localObject = localMac2;
        return localObject;
      }
      catch (NoSuchAlgorithmException localNoSuchAlgorithmException2)
      {
      }
      String[] arrayOfString = { "HmacSHA256", "hmacSHA256", "HMAC-SHA256", "hmac-sha256", "HMAC/SHA256", "hmac/sha256" };
      int i = arrayOfString.length;
      int j = 0;
      while (true)
        while (true)
        {
          if (j >= i)
            break label107;
          String str = arrayOfString[j];
          try
          {
            Mac localMac1 = Mac.getInstance(str);
            localObject = localMac1;
            if (localObject != null)
              sLastValidAlgorithm = str;
          }
          catch (NoSuchAlgorithmException localNoSuchAlgorithmException1)
          {
            while (true)
              localObject = null;
            j++;
          }
        }
      label107: Object localObject = null;
    }
  }

  public static void setSignedBody(RequestParams paramRequestParams, String paramString)
  {
    String str = null;
    if (paramString != null)
      str = String.format("%s.%s", new Object[] { generateSignature(paramString), paramString });
    paramRequestParams.put("signed_body", str);
    paramRequestParams.put(SIGNATURE_KEY_VERSION_FIELD_NAME, SIGNATURE_KEY_VERSION);
  }
}