Add a discount programmatically to an Order in Woocommerce 3.2+
The only available feature to make a discount programmatically for an Order, is tricking the Fee API. For info, this trick is not recommended by woocommerce, but used by many people as there is not a discount feature in Woocommerce outside Coupons.
The following function will allow you to make a fixed discount of any amount or a percentage discount. The order need to exist (to be saved before).
The function code (For Woocommerce versions 3.2+):
/**
* Add a discount to an Orders programmatically
* (Using the FEE API - A negative fee)
*
* @since 3.2.0
* @param int $order_id The order ID. Required.
* @param string $title The label name for the discount. Required.
* @param mixed $amount Fixed amount (float) or percentage based on the subtotal. Required.
* @param string $tax_class The tax Class. '' by default. Optional.
*/
function wc_order_add_discount( $order_id, $title, $amount, $tax_class = '' ) {
$order = wc_get_order($order_id);
$subtotal = $order->get_subtotal();
$item = new WC_Order_Item_Fee();
if ( strpos($amount, '%') !== false ) {
$percentage = (float) str_replace( array('%', ' '), array('', ''), $amount );
$percentage = $percentage > 100 ? -100 : -$percentage;
$discount = $percentage * $subtotal / 100;
} else {
$discount = (float) str_replace( ' ', '', $amount );
$discount = $discount > $subtotal ? -$subtotal : -$discount;
}
$item->set_tax_class( $tax_class );
$item->set_name( $title );
$item->set_amount( $discount );
$item->set_total( $discount );
if ( '0' !== $item->get_tax_class() && 'taxable' === $item->get_tax_status() && wc_tax_enabled() ) {
$tax_for = array(
'country' => $order->get_shipping_country(),
'state' => $order->get_shipping_state(),
'postcode' => $order->get_shipping_postcode(),
'city' => $order->get_shipping_city(),
'tax_class' => $item->get_tax_class(),
);
$tax_rates = WC_Tax::find_rates( $tax_for );
$taxes = WC_Tax::calc_tax( $item->get_total(), $tax_rates, false );
print_pr($taxes);
if ( method_exists( $item, 'get_subtotal' ) ) {
$subtotal_taxes = WC_Tax::calc_tax( $item->get_subtotal(), $tax_rates, false );
$item->set_taxes( array( 'total' => $taxes, 'subtotal' => $subtotal_taxes ) );
$item->set_total_tax( array_sum($taxes) );
} else {
$item->set_taxes( array( 'total' => $taxes ) );
$item->set_total_tax( array_sum($taxes) );
}
$has_taxes = true;
} else {
$item->set_taxes( false );
$has_taxes = false;
}
$item->save();
$order->add_item( $item );
$order->calculate_totals( $has_taxes );
$order->save();
}
Code goes in function.php file of your active child theme (active theme). Tested and works.
USAGE Examples:
1) Fixed discount of $12
(with a dynamic $order_id
):
wc_order_add_discount( $order_id, __("Fixed discount"), 12 );
2) Percentage discount of 5%
(with a dynamic $order_id
):
wc_order_add_discount( $order_id, __("Discount (5%)"), '5%' );
The amount (or the percentage) can be also a dynamic variable…
Actually you can just make hook before calculate tax etc, get subtotal, apply discount, done :) It automatically apply for Order message etc, it is visible also in backend in proper way. Even after remove hook, info about discount stay in order information.
// Hook before calculate fees
add_action('woocommerce_cart_calculate_fees' , 'add_user_discounts');
/**
* Add custom fee if more than three article
* @param WC_Cart $cart
*/
function add_user_discounts( WC_Cart $cart ){
//any of your rules
// Calculate the amount to reduce
$discount = $cart->get_subtotal() * 0.5;
$cart->add_fee( 'Test discount 50%', -$discount);
}