I have an extension in progress at https://github.com/jboeke/com.avietech.multitax
What I'm hoping to do is combine multiple tax rates into one. The extension properly rejiggers the tax values and actual amount as expected but NOT the visible price or description of the tax (i.e. - price-field-amount) to the right of the quantity input.
As you can see, my tax rate of 6.25% has been applied as expected and the Total Fee(s) reflects (20 * 1.0625). So why do I still see "$ 20 (includes Tax of $ 0)" when the expected value is "$ 21.25 (includes Tax of $ 1.25)"?
function multitax_civicrm_buildAmount sets, what I believe, are the relevant values:
$option['tax_rate'] = $totaltaxrate / 100;
$option['tax_amount'] = $option['amount'] * $option['tax_rate'];
Are there other values I need to set to change the description to accurately reflect the adjusted taxes?