Woocommerce: custom price based on user input

Question

I did not want to post here but I could not find the answer I was looking for and I do not have enough reputation to comment on other VERY SIMILAR questions to get my exact answer.

I found an almost perfect answer from this post: WooCommerce: Add product to cart with price override?

using the code:

add_action( 'woocommerce_before_calculate_totals', 'add_custom_price');

function add_custom_price( $cart_object ) {
      $custom_price = 10; // This will be your custome price  
      foreach ( $cart_object->cart_contents as $key => $value ) {
          $value['data']->price = $custom_price;
      }
 }

and it works great...if you set a hard coded custom price.

My question is: How can I set a custom price based on user input?

I have tried every way I can think of to pass information (I even tried using cookies, globals, sessions) and none of them worked how I wanted and all of them were, at BEST, hacks.

The specific product in question is a donation and the customer wants the user to be able to set the donation price (rather than just creating a variable product with set price points).

On the donation page when the user submits the donation form I am adding the donation product to the cart like so:

$donation_success = $woocommerce->cart->add_to_cart($donation_id); 

My donation product has a set price of 0.00 so when it is added to the cart it has a price of 0.00 (I don't know if the price is set at this point or later)

I have tried passing in information at this point using the last variable in the add_to_cart method which accepts an array of arguments but I couldn't seem to get that to work either.

I am sure the answer is simple but I have been trying for hours to do this right and I cannot get it to work. I am out of ideas.

The actual code I am using at the moment is slightly different than was suggested by the answerer of the above post but works basically the same:

add_action( 'woocommerce_before_calculate_totals', 'woo_add_donation');

function woo_add_donation() {
    global $woocommerce;

    $donation = 10;
    foreach ( WC()->cart->get_cart() as $cart_item_key => $cart_item ) {
        if($cart_item['data']->id == 358 || $cart_item['data']->id == 360){
            $cart_item['data']->set_price($donation);
        }
    }
}

Thanks in advance for any helpful advice!

Answer 1

I found a solution which is not elegant but works for my purposes.

I was trying to use cookies before but I didn't set the cookie path so it was only available to the page it was set on.

I am now setting a cookie with the donation price:

setcookie("donation", $_GET['donation'], 0, "/");

Then I am setting the price like so:

add_action( 'woocommerce_before_calculate_totals', 'woo_add_donation');

function woo_add_donation() {
    global $woocommerce;

    foreach ( WC()->cart->get_cart() as $cart_item_key => $cart_item ) {
        if($cart_item['data']->id == 358 && ! empty($_COOKIE['donation'])){
            $cart_item['data']->set_price($_COOKIE['donation']);
        }
    }
}