/*
 * Copyright (C) 2009-2018 by the geOrchestra PSC
 *
 * This file is part of geOrchestra.
 *
 * geOrchestra is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free
 * Software Foundation, either version 3 of the License, or (at your option)
 * any later version.
 *
 * geOrchestra is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * geOrchestra.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.georchestra.console;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;

import javax.net.ssl.HttpsURLConnection;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.json.JSONException;
import org.json.JSONObject;

/**
 * Class used to verify CaptchaV2 response
 *
 * @author Pierre Jego
 *
 */
public class ReCaptchaV2 {

    private static final Log LOG = LogFactory.getLog(ReCaptchaV2.class.getName());

    /**
     *
     * @param url
     * @param privateKey
     * @param gRecaptchaResponse
     *
     * @return true if validaded on server side by google, false in case of error or
     *         if an exception occurs
     */
    public boolean isValid(String url, String privateKey, String gRecaptchaResponse) {
        boolean isValid = false;

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

            // add request header
            con.setRequestMethod("POST");
            String postParams = "secret=" + privateKey + "&response=" + gRecaptchaResponse;

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

            if (LOG.isDebugEnabled()) {
                int responseCode = con.getResponseCode();
                LOG.debug("\nSending 'POST' request to URL : " + url);
                LOG.debug("Post parameters : " + postParams);
                LOG.debug("Response Code : " + responseCode);
            }

            // getResponse
            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
            LOG.debug(response.toString());

            JSONObject captchaResponse;
            try {
                captchaResponse = new JSONObject(response.toString());

                if (captchaResponse.getBoolean("success")) {
                    isValid = true;
                } else {
                    // Error in response
                    LOG.info("The user response to recaptcha is not valid. The error message is '"
                            + captchaResponse.getString("error-codes")
                            + "' - see Error Code Reference at https://developers.google.com/recaptcha/docs/verify.");
                }
            } catch (JSONException e) {
                // Error in response
                LOG.error("Error while parsing ReCaptcha JSON response", e);
            }
        } catch (IOException e) {
            LOG.error("An error occured when trying to contact google captchaV2", e);
        }

        return isValid;
    }

}
