Disable payment gateway based on number of items and product category in WooCommerce cart

I am using the following code, which allows me to set a minimal quantity of products in cart to proceed payment

// Allow order only product quantity increment

function s5_unsetting_payment_gateway( $available_gateways ) {
  if ( ! is_admin() ) {
    $cart_quantity = WC()->cart->get_cart_contents_count();

    if ( ( $cart_quantity % 6 ) !== 0 ) {
        unset($available_gateways['cod']);
        unset($available_gateways['bacs']);
    }
  }

  return $available_gateways;
}
add_filter( 'woocommerce_available_payment_gateways', 's5_unsetting_payment_gateway', 10, 1 );

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Is there some option to exclude some specific category?

For example:

I need to set the minimum quantity for one order for 6 pieces of goods (applies to all categories).

For one category of products (ID 2), however, I want that if there are only goods from this category in the basket, set the minimum for the order to 3 pieces.

Any advice?

Answer

This answer contains:

• If a product does not belong to the specific category, the minimum quantity will be 6
• If all products do belong to that one category, the minimum quantity will be 3

So you get:

function filter_woocommerce_available_payment_gateways( $payment_gateways ) {
    // Not on admin
    if ( is_admin() ) return $payment_gateways;

    // Term_id
    $cat_id = 2;
    
    // Default
    $minimum_quantity = 3;
    
    // WC Cart
    if ( WC()->cart ) {
        // Get total items in cart, counts number of products and quantity per product
        $cart_quantity = WC()->cart->get_cart_contents_count();
        
        // Loop through cart items
        foreach ( WC()->cart->get_cart() as $cart_item ) {
            // When a product does not belong to the specific category, the if condition will apply
            if ( ! has_term( $cat_id, 'product_cat', $cart_item['product_id'] ) ) {
                $minimum_quantity = 6;
                break;
            }
        }
    
        // Condition modulo
        if ( ( $cart_quantity % $minimum_quantity ) !== 0 ) {
            // Bacs
            if ( isset( $payment_gateways['bacs'] ) ) {
                unset( $payment_gateways['bacs'] );
            }
            
            // Cod
            if ( isset( $payment_gateways['cod'] ) ) {
                unset( $payment_gateways['cod'] );
            }  
        }
    }
    
    return $payment_gateways;
}
add_filter( 'woocommerce_available_payment_gateways', 'filter_woocommerce_available_payment_gateways', 10, 1 );