create Schema.org data from Woocommerce course data

<?php
/*
   Plugin Name: WooCommerce Schema.org Course Data
   Description: Adds schema.org course and courseInstance data to WooCommerce products
   Version: 1.3
   Author: Aaron Lowndes
*/

if (!defined('ABSPATH')) exit; // Exit if accessed directly

class WC_Schema_Course_Data {
    public function __construct() {
        add_action('woocommerce_after_single_product', array($this, 'output_schema_data'));
    }

    public function output_schema_data() {
        global $product;
        
        if (!$this->is_course($product)) return;

        $schema = array(
            '@context' => 'https://schema.org',
            '@type' => 'Course',
            'name' => $product->get_name(),
            'description' => $product->get_short_description(),
            'provider' => array(
                '@type' => 'Organization',
                'name' => 'Melbourne Climbing School',
                'url' => home_url()
            ),
            'offers' => $this->get_course_offers($product),
            'hasCourseInstance' => $this->get_course_instances($product)
        );

        echo '<script type="application/ld+json">' . json_encode($schema) . '</script>';
    }

    private function is_course($product) {
        return $product->get_type() == 'registrations';
    }

    private function get_course_offers($product) {
        return array(
            '@type' => 'Offer',
            'price' => $product->get_price(),
            'priceCurrency' => get_woocommerce_currency(),
            'availability' => $product->is_in_stock() ? 'https://schema.org/InStock' : 'https://schema.org/OutOfStock',
            'url' => get_permalink($product->get_id()),
            'category' => $this->get_product_category($product),
            'hasMerchantReturnPolicy' => array(
                '@type' => 'MerchantReturnPolicy',
                'applicableCountry' => 'AU',
                'returnPolicyCategory' => 'https://schema.org/MerchantReturnFiniteReturnWindow',
                'returnWindow' => array(
                    '@type' => 'MonetaryAmount',
                    'value' => '7',
                    'unitCode' => 'DAY'
                ),
                'refundType' => 'https://schema.org/PartialRefund',
                'returnMethod' => 'https://schema.org/ReturnAtKiosk'
            )
        );
    }

    private function get_product_category($product) {
        $categories = get_the_terms($product->get_id(), 'product_cat');
        if ($categories && !is_wp_error($categories)) {
            return $categories[0]->name;
        }
        return 'Climbing Course'; // Default category if none is set
    }

	private function get_course_instances($product) {
		$instances = array();
		$variations = $product->get_children();

		foreach ($variations as $variation_id) {
			$variation = wc_get_product($variation_id);
			$variation_data = $variation->get_data();

			$instance = array(
				'@type' => 'CourseInstance',
				'name' => $variation->get_name(),
				'url' => $variation->get_permalink(),
				'sku' => $variation->get_sku(),
				'description' => $variation->get_description(),
				'courseMode' => ['onsite'],
				'eventAttendanceMode' => 'https://schema.org/OfflineEventAttendanceMode',
				'courseWorkload' => 'PT8H', // Assumes 8 hours per day, modify as needed
				'offers' => array(
					'@type' => 'Offer',
					'price' => $variation->get_price(),
					'priceCurrency' => get_woocommerce_currency(),
					'availability' => $variation->is_in_stock() ? 'https://schema.org/InStock' : 'https://schema.org/OutOfStock',
					'url' => $variation->get_permalink(),
					'category' => $this->get_product_category($product)
				)
			);

			// Extract dates from attributes
			$attributes = $variation->get_attributes();
			if (isset($attributes['dates'])) {
				$dates_json = $attributes['dates'];
				$dates_data = json_decode($dates_json, true);
				if ($dates_data && isset($dates_data['dates']) && is_array($dates_data['dates']) && !empty($dates_data['dates'])) {
					$start_date = $dates_data['dates'][0]; // First date in the array
					$end_date = end($dates_data['dates']); // Last date in the array

					// Get start and end times from meta data
					$start_time = $variation->get_meta('_event_start_time', true) ?: '09:00';
					$end_time = $variation->get_meta('_event_end_time', true) ?: '17:00';

					// Combine dates and times
					$instance['startDate'] = date('c', strtotime("$start_date $start_time"));
					$instance['endDate'] = date('c', strtotime("$end_date $end_time"));
				}
			}

			// Add course schedule based on SKU
			if ($variation->get_sku() === 'ltl') {
				$instance['courseSchedule'] = '6:30 PM to 9:30 PM each day';
			} else {
				$instance['courseSchedule'] = '9:00 AM to 5:00 PM each day';
			}

			// Add image
			$image_id = $variation->get_image_id();
			$image_array = wp_get_attachment_image_src($image_id, array('500','500'), true);
			if ($image_array) {
				$instance['image'] = $image_array[0];
			}

			// Add location
			$location_name = $variation->get_meta('location_name', true);
			if ($location_name) {
				$instance['location'] = array(
					'@type' => 'Place',
					'name' => $location_name
				);
			}

			$instances[] = $instance;
		}

		return $instances;
	}

    private function format_datetime($datetime) {
        // Convert to ISO 8601 format
        return date('c', strtotime($datetime));
    }
}

new WC_Schema_Course_Data();