D-Net

package eu.dnetlib.uoaadmintoolslibrary.recaptcha;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.beans.factory.annotation.Configurable;

import org.springframework.boot.web.client.RestTemplateBuilder;

import org.springframework.context.annotation.Bean;

import org.springframework.stereotype.Service;

import org.springframework.util.StringUtils;

import org.springframework.web.client.RestOperations;

import java.net.URI;

import java.util.regex.Pattern;

import eu.dnetlib.uoaadmintoolslibrary.configuration.properties.GoogleConfig;

import eu.dnetlib.uoaadmintoolslibrary.entities.email.GoogleResponse;

import eu.dnetlib.uoaadmintoolslibrary.handlers.InvalidReCaptchaException;

@Service

@Configurable

public class VerifyRecaptcha {

    @Autowired

    private RestOperations restTemplate;

    @Autowired

    private GoogleConfig googleConfig;

    private static Pattern RESPONSE_PATTERN = Pattern.compile("[A-Za-z0-9_-]+");

    @Bean

    public RestOperations restTemplate(RestTemplateBuilder builder) {

        return builder.build();

    }

    public void processResponse(String response) throws InvalidReCaptchaException {

        if(!responseSanityCheck(response)) {

            throw new InvalidReCaptchaException("Response contains invalid characters");

        }

        URI verifyUri = URI.create(String.format(

                "https://www.google.com/recaptcha/api/siteverify?secret=%s&response=%s",

                googleConfig.getSecret(), response));

        GoogleResponse googleResponse = restTemplate.getForObject(verifyUri, GoogleResponse.class);

        if(!googleResponse.isSuccess()) {

            throw new InvalidReCaptchaException("reCaptcha was not successfully validated");

        }

    }

    private boolean responseSanityCheck(String response) {

        return StringUtils.hasLength(response) && RESPONSE_PATTERN.matcher(response).matches();

    }

}