Allow Multiple Payments In The Same WooCommerce Order

add_action( 'init', function() {
    $supports_array = array( 'title' );
    $args = array(
        'labels' => array(
            'name' => 'Payments',
            'singular_name' => 'Payments'
        ),
        'capability_type' => 'shop_order',
        'public' => false,
        'supports' => $supports_array,
        'rewrite' => false,
        'show_ui' => true,
        'show_in_menu' => current_user_can( 'edit_others_shop_orders' ) ? 'woocommerce' : false,
        'menu_position' => 3,
    );    
    register_post_type( 'payment', $args );
});

add_action( 'woocommerce_order_after_calculate_totals', function( $and_taxes, $order ) {

    $payments = get_posts( [ 'post_type' => 'payment', 'post_status' => 'publish', 'numberposts' => -1, 'title' => $order->get_id(), 'fields' => 'ids' ] );
	
    if ( $payments ) {

        $total = $order->get_total();
        $paid = 0.00;
        foreach ( $payments as $payment_id ) {
            $amount = get_field( "amount", $payment_id );
            $paid += $amount;
        }
        $new_total = $total - $paid;
        $order->set_total( $new_total );
        if ( $new_total > 0 ) $order->set_status( 'pending' );
        $order->save();
		
	}
	
}, 9999, 2 );

add_action( 'acf/save_post', function( $post_id ) {
    if ( get_post_type( $post_id ) !== 'payment' && get_post_status( $post_id ) !== 'publish' ) return;
    $order = wc_get_order( get_the_title( $post_id ) );
    if ( ! $order ) return;
    $order->calculate_totals();
});

add_action( 'woocommerce_thankyou', function( $order_id ) {

    $order = wc_get_order( $order_id );
    if ( $order->has_status( 'failed' ) ) return;
	
    $my_post = array(
        'post_title' => $order_id,
        'post_status' => 'publish',
        'post_type' => 'payment',
    );
    $new_post_id = wp_insert_post( $my_post );
	
	update_field( 'amount', $order->get_total(), $new_post_id );
	$order->calculate_totals();
	
});

add_action( 'woocommerce_review_order_before_payment', function() {
    
    $chosen = WC()->session->get( 'deposit_chosen' );
    $chosen = empty( $chosen ) ? WC()->checkout->get_value( 'deposit' ) : $chosen;
    $chosen = empty( $chosen ) ? '100' : $chosen;
            
    $args = array(
        'type' => 'radio',
        'class' => array( 'form-row-wide', 'update_totals_on_change' ),
        'options' => array(
            '100' => 'Pay 100%',
            '30' => 'Pay 30% Deposit',
        ),
        'default' => $chosen,
    );
    
    echo '<p><b>Payment Option</b></p>';
    woocommerce_form_field( 'deposit', $args, $chosen );

}, 1 );

add_action( 'woocommerce_checkout_update_order_review', function( $posted_data ) {
    parse_str( $posted_data, $output );
    if ( isset( $output['deposit'] ) ) {
        WC()->session->set( 'deposit_chosen', $output['deposit'] );
    }
});

add_filter( 'woocommerce_calculated_total', function( $total, $cart ) {
	if ( ! WC()->session->get( 'deposit_chosen' ) || WC()->session->get( 'deposit_chosen' ) == '100' ) return $total;
    return $total * 0.3;
}, 9999, 2 );

add_action( 'woocommerce_admin_order_totals_after_total', function ( $order_id ) {
    echo '<tr><td class="label">Payments:</td><td width="1%"></td><td class="total"><ul style="margin:0">';
    $payments = get_posts( [ 'post_type' => 'payment', 'post_status' => 'publish', 'numberposts' => -1, 'title' => $order_id, 'fields' => 'ids' ] );
    if ( $payments ) {
        foreach ( $payments as $payment_id ) {
            $amount = get_field( "amount", $payment_id );
            echo '<li style="margin:0"><a href="' . get_edit_post_link( $payment_id ) . '">' . wc_price( $amount ) . '</a> (' . get_the_time( 'd-m-y', $payment_id ) . ')</li>';
        }
    }
    echo '</ul></td></tr>';
});