add basic VAT abilities to Leaky Paywall

leaky-paywall-vat.php

add_action( 'leaky_paywall_before_registration_form', 'omg_show_vat_on_subscription_details' );

function omg_show_vat_on_subscription_details( $level ) {

  $vat_price = omg_calculate_vat_total( $level['price'] );

  echo '<p><strong>With VAT Tax: </strong> ' . leaky_paywall_get_current_currency_symbol() . $vat_price . '</p>';

}


add_filter( 'leaky_paywall_subscription_data', 'omg_add_vat_tax' );

function omg_add_vat_tax( $subscription_data ) {

  $amount = $subscription_data['amount'];
  $subscription_data['amount'] = omg_calculate_vat_total( $amount );

  return $subscription_data;

}

add_filter( 'leaky_paywall_create_stripe_plan', 'omg_add_vat_tax_to_stripe_plan', 10, 3 );

function omg_add_vat_tax_to_stripe_plan( $args, $level, $level_id ) {

  if ( isset( $_COOKIE['leaky-paywall-coupon'] ) ) {
    $stripe_amount = $level['price'] * 100;
  } else {
    $stripe_amount = $args['amount']; // 3500
  }
  
  $regular_amount = $stripe_amount / 100; // 35.00
  $regular_with_vat = omg_calculate_vat_total( $regular_amount );
  $regular_with_vat_striped = $regular_with_vat * 100;

  $args['amount'] = $regular_with_vat_striped;

  return $args;

}


function omg_calculate_vat_total( $amount ) {

  $vat_tax = $amount * 0.21; // 21% 
  $total_with_vat = $amount + $vat_tax;

  return number_format( $total_with_vat, 2 );
}