package eu.dnetlib.openaire.user.utils;

import org.apache.log4j.Logger;

import javax.json.Json;
import javax.json.JsonObject;
import javax.json.JsonReader;
import javax.net.ssl.HttpsURLConnection;
import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.InputStreamReader;
import java.io.StringReader;
import java.net.URL;

public class VerifyRecaptcha {

    public static final String url = "https://www.google.com/recaptcha/api/siteverify";

    //private final static String USER_AGENT = "Mozilla/5.0";

    private static Logger logger = Logger.getLogger(VerifyRecaptcha.class);
    public static boolean verify(String gRecaptchaResponse, String secret) {

        logger.debug("Recaptch secret " + secret);
        logger.debug("response " + gRecaptchaResponse);
        
        if (gRecaptchaResponse == null || "".equals(gRecaptchaResponse)) {
            return false;
        }

        try{
            URL obj = new URL(url);
            HttpsURLConnection con = (HttpsURLConnection) obj.openConnection();

            // add reuqest header
            con.setRequestMethod("POST");
            //con.setRequestProperty("User-Agent", USER_AGENT);
            con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");

            String postParams = "secret=" + secret + "&response="
                    + gRecaptchaResponse;

            // Send post request
            con.setDoOutput(true);
            DataOutputStream wr = new DataOutputStream(con.getOutputStream());
            wr.writeBytes(postParams);
            wr.flush();
            wr.close();

            int responseCode = con.getResponseCode();
            logger.debug("\nSending 'POST' request to URL : " + url);
            logger.debug("Post parameters : " + postParams);
            logger.info("recaptcha response Code : " + responseCode);

            BufferedReader in = new BufferedReader(new InputStreamReader(
                    con.getInputStream()));
            String inputLine;
            StringBuffer response = new StringBuffer();

            while ((inputLine = in.readLine()) != null) {
                response.append(inputLine);
            }
            in.close();

            // print result
            logger.debug(response.toString());

            //parse JSON response and return 'success' value
            JsonReader jsonReader = Json.createReader(new StringReader(response.toString()));
            JsonObject jsonObject = jsonReader.readObject();
            jsonReader.close();

            return jsonObject.getBoolean("success");

        } catch(Exception e){
            logger.error("Error validating recaptcha");
            return false;
        }
    }

}