install.xml

<?xml version="1.0"?>
<!DOCTYPE modification SYSTEM "http://www.simplemachines.org/xml/modification">
<modification xmlns="http://www.simplemachines.org/xml/modification" xmlns:smf="http://www.simplemachines.org/">
	<id>motokochan:recaptchaforsmf</id>
	<name>Visual Verification Options</name>

	<file name="$sourcedir/ManageSettings.php">
		<operation>
			<search position="before"><![CDATA[
			array('desc', 'configure_verification_means_desc'),
]]></search>
			<add><![CDATA[
				array('check', 'recaptcha_enabled', 'subtext' => $txt['recaptcha_enable_desc']),
]]></add>
		</operation>
		<operation>
			<search position="after"><![CDATA[
			// Clever Thomas, who is looking sheepy now? Not I, the mighty sword swinger did say.
]]></search>
			<add><![CDATA[
			// reCAPTCHA
			array('title', 'recaptcha_configure'),
			array('desc', 'recaptcha_configure_desc', 'class' => 'windowbg'),
				array('text', 'recaptcha_public_key'),
				array('text', 'recaptcha_private_key'),
				array('select', 'recaptcha_theme', array('light' => $txt['recaptcha_theme_light'],
									 'dark' => $txt['recaptcha_theme_dark'], )),
]]></add>
		</operation>
	</file>

	<file name="$sourcedir/Subs-Editor.php">
		<operation>
			<search position="after"><![CDATA[
		);
	$thisVerification = &$context['controls']['verification'][$verificationOptions['id']];
]]></search>
			<add><![CDATA[
            'use_recaptcha' => !empty($modSettings['recaptcha_enabled']),
]]></add>
		</operation>
		<operation>
			<search position="replace"><![CDATA[
	if (empty($thisVerification['show_visual']) && empty($thisVerification['number_questions']))
]]></search>
			<add><![CDATA[
	if (empty($thisVerification['show_visual']) && empty($thisVerification['number_questions']) && empty($thisVerification['use_recaptcha']))
]]></add>
		</operation>
		<operation>
			<search position="before"><![CDATA[
		if ($thisVerification['number_questions'] && (!isset($_SESSION[$verificationOptions['id'] . '_vv']['q']) || !isset($_REQUEST[$verificationOptions['id'] . '_vv']['q'])))
			fatal_lang_error('no_access', false);
]]></search>
			<add><![CDATA[

		//reCAPTCHA Verification
        if(!empty($modSettings['recaptcha_enabled']) && ($modSettings['recaptcha_enabled'] == 1 && !empty($modSettings['recaptcha_public_key']) && !empty($modSettings['recaptcha_private_key'])))
        {
            $recaptcha = new \ReCaptcha\ReCaptcha($modSettings['recaptcha_private_key']);

            // Was there a reCAPTCHA response?
            if(isset($_REQUEST["g-recaptcha-response"]))
            {
                $resp = $recaptcha->verify($_REQUEST["g-recaptcha-response"], $_SERVER["REMOTE_ADDR"]);

                if (!$resp->isSuccess())
                    $verification_errors[] = 'wrong_verification_code';
            }
            else
                $verification_errors[] = 'need_verification_code';
        }
]]></add>
		</operation>
	</file>
</modification>