Oauth Authenticator

/**
 * Created by akshay on 28/8/17.
 */
public class TokenAuthenticator implements Authenticator {
    private final Context c;

    public TokenAuthenticator(Context c) {
        this.c = c;
    }

    private static int responseCount(Response response) {
        int result = 1;
        while ((response = response.priorResponse()) != null) {
            result++;
        }
        return result;
    }

    @Override
    public Request authenticate(Route route, Response response) throws IOException {
        if (responseCount(response) >= 2) {
            // If both the original call and the call with refreshed token failed,
            // it will probably keep failing, so don't try again.
            return null;
        }

        Log.e("authenticate", "refresh_token  " + response.code());
        // We need a new client, since we don't want to make another call using our client with access token
        TokenService tokenClient = ServiceGenerator.createService(TokenService.class);
        Call<TokenModel> call = tokenClient.refreshToken(
                "refresh_token",
                Constants.CLIENT_SECRET,
                "1",
                Utility.getDefaults(Constants.TAG_REFRESH_TOKEN, c)
        );
        try {
            retrofit2.Response<TokenModel> tmr = call.execute();
            Log.e("refresh_token", "" + tmr.isSuccessful() + "  " + tmr.message().toString() + "  " + call);
            if (tmr.code() == 200) {
                // Log.e("refresh_token", "" + tmr.isSuccessful() + "  " + tmr.message().toString() + "  " + call);
                TokenModel tm = tmr.body();
                Log.e("refresh_token", "isSuccessful " + tm.getToken_type() + "  " + tm.getRefresh_token() + "  --------  " + tm.getExpires_in());
                Utility.setDefaults(Constants.TAG_REFRESH_TOKEN, tm.getRefresh_token(), c);
                Utility.setDefaults(Constants.TAG_TOKEN, tm.getAccess_token(), c);
                Utility.setDefaultsLong(Constants.TAG_REFRESH_TIME, Utility.getCalculatedRefreshTime(tm.getExpires_in()));
                return response.request().newBuilder()
                        .header("Authorization", tm.getToken_type() + " " + tm.getAccess_token())
                        .build();
            } else {
                return null;
            }
        } catch (IOException e) {
            Log.e("Exc", String.valueOf(e.getMessage()));
            return null;
        }
    }
}