Extending Taxation

<?php

return [
    'driver' => 'system',
];

<?php

namespace App\Drivers;

use Lunar\Base\TaxDriver;
use Illuminate\Support\Collection;

class TaxJar implements TaxDriver
{
    /**
     * Set the shipping address.
     *
     * @param  \Lunar\DataTypes\Address|null  $address
     * @return self
     */
    public function setShippingAddress(Address $address = null)
    {
        // ...
        return $this;
    }

    /**
     * Set the currency.
     *
     * @param  \Lunar\Models\Currency  $currency
     * @return self
     */
    public function setCurrency(Currency $currency)
    {
        // ...
        return $this;
    }

    /**
     * Set the billing address.
     *
     * @param  \Lunar\DataTypes\Address|null  $address
     * @return self
     */
    public function setBillingAddress(Address $address = null)
    {
        // ...
        return $this;
    }

    /**
     * Set the purchasable item.
     *
     * @param  \Lunar\Base\Purchasable|null  $address
     * @return self
     */
    public function setPurchasable(Purchasable $purchasable)
    {
        // ...
        return $this;
    }

    /**
     * Return the tax breakdown from a given sub total.
     *
     * @param  int  $subTotal
     */
    public function getBreakdown($subTotal): Collection
    {
        return collect([ /* ... */ ]);
    }
}

public function boot()
{
    \Lunar\Facades\Taxes::extend('taxjar', function ($app) {
        return $app->make(TaxJar::class);
    })
}