feat(integration): add Simple Basic Contact Form integration

autoload.php

@@ -68,6 +68,7 @@
         'MC4WP_Queue' => '/includes/class-queue.php',
         'MC4WP_Queue_Job' => '/includes/class-queue-job.php',
         'MC4WP_Registration_Form_Integration' => '/integrations/wp-registration-form/class-registration-form.php',
+        'MC4WP_Simple_Basic_Contact_Form_Integration' => '/integrations/simple-basic-contact-form/class-simple-basic-contact-form.php',
         'MC4WP_Tools' => '/includes/class-tools.php',
         'MC4WP_Upgrade_Routines' => '/includes/admin/class-upgrade-routines.php',
         'MC4WP_User_Integration' => '/includes/integrations/class-user-integration.php',

integrations/bootstrap.php

@@ -43,6 +43,7 @@ function mc4wp_admin_after_integration_settings(MC4WP_Integration $integration,
 mc4wp_register_integration('memberpress', 'MC4WP_MemberPress_Integration');
 mc4wp_register_integration('affiliatewp', 'MC4WP_AffiliateWP_Integration');
 mc4wp_register_integration('give', 'MC4WP_Give_Integration');
+mc4wp_register_integration('simple-basic-contact-form', 'MC4WP_Simple_Basic_Contact_Form_Integration');
 mc4wp_register_integration('custom', 'MC4WP_Custom_Integration', true);
 mc4wp_register_integration('woocommerce', 'MC4WP_WooCommerce_Integration');
 

integrations/simple-basic-contact-form/class-simple-basic-contact-form.php

@@ -0,0 +1,117 @@
+<?php
+
+defined('ABSPATH') or exit;
+
+/**
+ * Class MC4WP_Simple_Basic_Contact_Form_Integration
+ *
+ * Integrates Mailchimp for WordPress with the Simple Basic Contact Form plugin.
+ *
+ * @since 4.9.0
+ * @ignore
+ */
+class MC4WP_Simple_Basic_Contact_Form_Integration extends MC4WP_Integration
+{
+    /**
+     * @var string
+     */
+    public $name = 'Simple Basic Contact Form';
+
+    /**
+     * @var string
+     */
+    public $description = 'Subscribes people from Simple Basic Contact Form forms.';
+
+    /**
+     * Add hooks
+     */
+    public function add_hooks()
+    {
+        add_filter('scf_filter_contact_form', [ $this, 'add_checkbox' ], 20);
+        add_action('scf_send_email', [ $this, 'process' ], 10, 5);
+    }
+
+    /**
+     * Adds the MC4WP checkbox to the Simple Basic Contact Form HTML.
+     *
+     * Inserts the checkbox before the closing </form> tag so it appears
+     * inside the form, just before the submit area.
+     *
+     * @param string $form_html The full contact form HTML.
+     * @return string Modified form HTML with the checkbox injected.
+     */
+    public function add_checkbox($form_html)
+    {
+        // do not add a checkbox when integration is implicit
+        if ($this->options['implicit']) {
+            return $form_html;
+        }
+
+        $checkbox_html = $this->get_checkbox_html();
+
+        // insert the checkbox just before the closing </form> tag
+        $form_html = str_ireplace('</form>', $checkbox_html . '</form>', $form_html);
+
+        return $form_html;
+    }
+
+    /**
+     * Process the form submission and subscribe the user if the checkbox was checked.
+     *
+     * Fires on the `scf_send_email` action after the contact form email is sent.
+     *
+     * @param string $recipient The email recipient.
+     * @param string $topic     The email subject.
+     * @param string $message   The email message body.
+     * @param string $headers   The email headers.
+     * @param string $email     The sender's email address (form submitter).
+     *
+     * @return bool
+     */
+    public function process($recipient, $topic, $message, $headers, $email)
+    {
+        // was sign-up checkbox checked?
+        if (! $this->triggered()) {
+            return false;
+        }
+
+        $parser = new MC4WP_Field_Guesser($this->get_data());
+        $data   = $parser->combine([ 'guessed', 'namespaced' ]);
+
+        // use the email from the action parameter if not found via field guesser
+        if (empty($data['EMAIL']) && ! empty($email)) {
+            $data['EMAIL'] = $email;
+        }
+
+        // do nothing if no email was found
+        if (empty($data['EMAIL'])) {
+            $this->get_log()->warning(sprintf('%s > Unable to find EMAIL field.', $this->name));
+            return false;
+        }
+
+        return $this->subscribe($data);
+    }
+
+    /**
+     * Are the required dependencies for this integration installed?
+     *
+     * @return bool
+     */
+    public function is_installed()
+    {
+        return function_exists('simple_contact_form');
+    }
+
+    /**
+     * Returns the UI elements to show on the settings page.
+     *
+     * Removes 'implicit' since this integration uses an explicit checkbox approach.
+     *
+     * @since 4.9.0
+     * @return array
+     */
+    public function get_ui_elements()
+    {
+        return array_diff(parent::get_ui_elements(), [ 'implicit' ]);
+    }
+}