Automatically add products to WooCommerce cart bas

What I'm trying to achieve here is the following:

Automatically add BonusProduct0 to cart when subtotal reaches 65
Automatically replace BonusProduct0 with BonusProduct1 when subtotal reaches 80
Automatically replace BonusProduct1 with BonusProduct2 when subtotal reaches 100
Remove all any bonus product that happens to be in the cart when subtotal goes below 65
Have the bonus products either zero-priced and unaccessible or normally priced and automatically reset their price when added to cart based on above conditions

Working code.

function add_product_if_not_there($product_id) {
    $found = false;
    foreach ( WC()->cart->get_cart() as $cart_item_key => $values ) {
        $_product = $values['data'];
        if ( $_product->get_id() == $product_id ) {
            $found = true;
            break;
        }
    }
    if (!$found)
        WC()->cart->add_to_cart( $product_id );

}

function remove_product_if_there($product_id) {
    foreach ( WC()->cart->get_cart() as $cart_item_key => $values ) {
        $_product = $values['data'];
        if ( $_product->get_id() == $product_id ) {
            WC()->cart->remove_cart_item( $cart_item_key );
            break;
        }
    }
}

abstract class FreeCookiesBundles
{
    const    NoCookiesBundle = 0;
    const   TwoCookiesBundle = 2;
    const ThreeCookiesBundle = 3;
    const  FourCookiesBundle = 4;
    const   TwoCookiesBundleId = 4920;
    const ThreeCookiesBundleId = 4921;
    const  FourCookiesBundleId = 4922;
} 

function bonus_add_product_to_cart() {
    global $woocommerce;

    if ( is_admin() )
        return ;

    $free_product_ids = array(FreeCookiesBundles::TwoCookiesBundleId,
                              FreeCookiesBundles::ThreeCookiesBundleId,
                              FreeCookiesBundles::FourCookiesBundleId);
    $cookies_bundle = FreeCookiesBundles::NoCookiesBundle;
    $cart_total_lvls = array(65, 100, 128);
    if ( ($woocommerce->cart->subtotal >= $cart_total_lvls[0]) &&
         ($woocommerce->cart->subtotal  < $cart_total_lvls[1])) {
        $cookies_bundle = FreeCookiesBundles::TwoCookiesBundle;
    } else if ( ($woocommerce->cart->subtotal >= $cart_total_lvls[1]) &&
                ($woocommerce->cart->subtotal  < $cart_total_lvls[2]) ) {
        $cookies_bundle = FreeCookiesBundles::ThreeCookiesBundle;
    } else if ( ($woocommerce->cart->subtotal >= $cart_total_lvls[2]) ) {
        $cookies_bundle = FreeCookiesBundles::FourCookiesBundle;
    }
    echo $cookies_bundle;

    switch ($cookies_bundle) {
        case FreeCookiesBundles::TwoCookiesBundle:
            add_product_if_not_there($free_product_ids[0]);
            remove_product_if_there($free_product_ids[1]);
            remove_product_if_there($free_product_ids[2]);
            break;
        case FreeCookiesBundles::ThreeCookiesBundle:
            add_product_if_not_there($free_product_ids[1]);
            remove_product_if_there($free_product_ids[0]);
            remove_product_if_there($free_product_ids[2]);
            break;
        case FreeCookiesBundles::FourCookiesBundle:
            add_product_if_not_there($free_product_ids[2]);
            remove_product_if_there($free_product_ids[0]);
            remove_product_if_there($free_product_ids[1]);
            break;
        default:
            remove_product_if_there($free_product_ids[0]);
            remove_product_if_there($free_product_ids[1]);
            remove_product_if_there($free_product_ids[2]);
    }
}
add_action( 'template_redirect', 'bonus_add_product_to_cart' );