GA4 Purchase Event for Easy Digital Downloads

add_action( 'wp_footer', function () {
    if ( ! function_exists( 'edd_is_success_page' ) || ! edd_is_success_page() || ! function_exists( 'edd_get_order_by' ) ) {
        return;
    }

    $session = edd_get_purchase_session();

    if ( empty( $session['purchase_key'] ) ) {
        return;
    }

    $order = edd_get_order_by( 'payment_key', $session['purchase_key'] );

    if ( ! $order || ! in_array( $order->status, array( 'complete', 'publish' ), true ) || edd_get_order_meta( $order->id, '_wpide_ga4_sent', true ) ) {
        return;
    }

    $items = array();

    foreach ( $order->get_items() as $item ) {
        $items[] = array(
            'item_id'   => (string) $item->product_id,
            'item_name' => $item->product_name,
            'price'     => round( (float) $item->total / max( 1, (int) $item->quantity ), 2 ),
            'quantity'  => (int) $item->quantity,
        );
    }

    $data = array(
        'transaction_id' => (string) $order->get_number(),
        'value'          => round( (float) $order->total, 2 ),
        'tax'            => round( (float) $order->tax, 2 ),
        'currency'       => $order->currency,
        'items'          => $items,
    );

    echo "<script>window.dataLayer = window.dataLayer || []; function gtag(){dataLayer.push(arguments);} gtag('event', 'purchase', " . wp_json_encode( $data ) . ");</script>\n";

    edd_update_order_meta( $order->id, '_wpide_ga4_sent', time() );
} );