How to use cart total to change cart items prices in WooCommerce - php

Question

I am trying to pass the total amount of the cart ($GetTotalPrice) from function cart_prices_GetPrice() to function cart_prices_ApplyPrice(), using a woocommerce_after_calculate_totals and woocommerce_before_calculate_totals hooks, but I get an empty value.
//Trying to get cart amount
add_action('woocommerce_after_calculate_totals', 'cart_prices_GetPrice');
function cart_prices_GetPrice() {
//Getting the cart amount
$GetTotalPrice = WC()->cart->get_cart_total();
return $GetTotalPrice;
}
//Applying custom price
add_action('woocommerce_before_calculate_totals', 'cart_prices_ApplyPrice');
function cart_prices_ApplyPrice( $cart_object ) {
//Getting the cart amount from first function
$totalprice = cart_prices_GetPrice(); // doesn't work and returns 0 :(
//price change to cost2
if( $totalprice != 0 && $totalprice >= 2000 ) {
foreach ( $cart_object->get_cart() as $cart_id => $cart_item ) {
// get products id
$product_id = $cart_item['product_id'];
if( $cart_item['product_id'] == $product_id ) {
// price change to cost2
$new_price1 = 0.20;
$cart_item['data']->set_price( $new_price1 );
}
}
}
}
At the same time, each of the functions separately works perfectly.
What am I doing wrong? Is it possible to somehow link two hook data so that the first one doesn't return an empty value?
Update:
I will not be able to refuse the hook woocommerce_before_calculate_totals, because I need to apply a separate price reduction for each product in the cart.

Answer 1

You can simply not use cart total in woocommerce_before_calculate_totals when you want to alter cart item price for many reasons…
Instead you will get cart item subtotal inside woocommerce_before_calculate_totals hook. On the code below I use the discounted cart item subtotal including taxes:
add_action('woocommerce_before_calculate_totals', 'customize_cart_item_prices');
function customize_cart_item_prices( $cart ) {
if ( is_admin() && ! defined( 'DOING_AJAX' ) )
return;
// Avoiding the hook repetition for price calculations
if ( did_action( 'woocommerce_before_calculate_totals' ) >= 2 )
return;
$threshold_amount = 1000; // Min subtotal
$discount_rate = 0.2; // price discount rate (20%)
$cart_items = $cart->get_cart();
// Getting non discounted cart items subtotal
$subtotal_excl_tax = array_sum( wp_list_pluck( $cart_items, 'line_subtotal' ) );
$subtotal_tax = array_sum( wp_list_pluck( $cart_items, 'line_subtotal_tax' ) );
// Getting discounted cart items subtotal
$total_excl_tax = array_sum( wp_list_pluck( $cart_items, 'line_total' ) );
$total_tax = array_sum( wp_list_pluck( $cart_items, 'line_tax' ) );
if( ( $total_excl_tax + $total_tax ) >= $threshold_amount ) {
// Loop through cart items
foreach ( $cart_items as $item ) {
$price = $item['data']->get_price(); // Get price
$item['data']->set_price( $price * ( 1 - $discount_rate ) ); // Set new price
}
}
}
Code goes in functions.php file of the active child theme (or active theme). Tested and works.
See on Change cart item prices in Woocommerce 3 answer code, to see how to handle minicart displayed custom cart item price.