<?php

defined('ABSPATH') or exit;

$section_widgets = get_option('sidebars_widgets', array());
$replaced        = false;

foreach ($section_widgets as $section => $widgets) {
    // WP has an "array_version" key that is not an array...
    if (! is_array($widgets)) {
        continue;
    }

    // loop through widget ID's
    foreach ($widgets as $key => $widget_id) {
        // does this widget ID start with "mc4wp_widget"?
        if (strpos($widget_id, 'mc4wp_widget') === 0) {
            // replace "mc4wp_widget" with "mc4wp_form_widget"
            $new_widget_id                       = str_replace('mc4wp_widget', 'mc4wp_form_widget', $widget_id);
            $section_widgets[ $section ][ $key ] = $new_widget_id;
            $replaced                            = true;
        }
    }
}


// update option if we made changes
if ($replaced) {
    update_option('sidebars_widgets', $section_widgets);
}

// update widget options
$options = get_option('widget_mc4wp_widget', false);
if ($options) {
    update_option('widget_mc4wp_form_widget', $options);

    // delete old option
    delete_option('widget_mc4wp_widget');
}