Order Tax Field Providers

Order tax field providers define selectable tax field strategies for WooCommerce order exports. They are registered through the storeaccountant_export_order_tax_field_provider filter and also register as regular export field providers through storeaccountant_export_field_provider. This keeps tax fields in the shared field pipeline while still allowing an order configuration to choose one tax strategy.

The provider must implement StoreAccountant\Tax\Contract\OrderTaxFieldProviderInterface. Tax field providers that add export columns should also implement StoreAccountant\Export\Contract\FieldProviderInterface and only support the order export when their provider ID matches the selected configuration value in ExportContext.

Hook

storeaccountant_export_order_tax_field_provider

Registration

<?php

add_filter(
    'storeaccountant_export_order_tax_field_provider',
    static function ( array $providers ): array {
        $providers['my_tax_provider'] = new MyTaxFieldProvider();

        return $providers;
    }
);

Each provider exposes a stable ID, a translated label, field definitions, and values for a WC_Order. The field mapping UI stores the selected tax provider on the export configuration. OrderTaxFieldValueProvider resolves values for the selected tax provider through the normal field value provider pipeline.

Built-in tax field providers register their field definitions after the normal order fields. Metadata-backed custom order fields are moved to the end by the field resolver and mapping repository, so the final order is fixed order fields, tax fields, then custom fields.

Top-level reusable tax classes:

StoreAccountant\Tax\Contract\OrderTaxFieldProviderInterface
StoreAccountant\Tax\Field\Provider\ExtendedOrderTaxFieldProvider
StoreAccountant\Tax\Field\Provider\SimpleOrderTaxFieldProvider
StoreAccountant\Tax\Field\Provider\OrderTaxFieldValueProvider
StoreAccountant\Tax\Admin\OrderTaxFieldProviderField

Order-specific tax support classes:

StoreAccountant\Order\Tax\OrderTaxFieldProviderRegistry
StoreAccountant\Order\Tax\OrderTaxRateResolver

Built-in providers:

• extended: creates separate item, shipping, and total tax fields per tax rate.
• simple: aggregates order tax into item tax and shipping tax columns.

Example Implementation

<?php

declare(strict_types=1);

namespace Acme\StoreAccountant;

use WC_Order;
use StoreAccountant\Contract\HookRegistrarInterface;
use StoreAccountant\Export\Contract\FieldProviderInterface;
use StoreAccountant\Export\ExportContext;
use StoreAccountant\Export\Field\Field;
use StoreAccountant\Export\Field\FieldValue;
use StoreAccountant\Export\Field\Type\NumberFieldType;
use StoreAccountant\Order\Export\Adapter\OrderExportAdapter;
use StoreAccountant\Tax\Contract\OrderTaxFieldProviderInterface;

final class CompactTaxFieldProvider implements OrderTaxFieldProviderInterface, FieldProviderInterface, HookRegistrarInterface {
    public const PROVIDER_ID = 'compact';

    public function register(): void {
        add_filter(
            'storeaccountant_export_order_tax_field_provider',
            function ( array $providers ): array {
                $providers[ self::PROVIDER_ID ] = $this;

                return $providers;
            }
        );

        add_filter(
            'storeaccountant_export_field_provider',
            function ( array $providers ): array {
                $providers[ 'order_tax_' . self::PROVIDER_ID ] = $this;

                return $providers;
            },
            HookRegistrarInterface::DEFAULT_PRIORITY + 10
        );
    }

    public function get_id(): string {
        return self::PROVIDER_ID;
    }

    public function get_label(): string {
        return __( 'Compact tax fields', 'storeaccountant' );
    }

    public function supports( ExportContext $context ): bool {
        return OrderExportAdapter::ADAPTER_ID === $context->export_type
            && self::PROVIDER_ID === (string) $context->get( 'tax_field_provider_id', '' );
    }

    public function get_fields( ExportContext $context ): array {
        return [
            'tax_total' => new Field( 'tax_total', 'tax_total', new NumberFieldType( NumberFieldType::FORMAT_DECIMAL ) ),
        ];
    }

    public function get_values( WC_Order $order, ExportContext $context ): array {
        return [
            'tax_total' => new FieldValue( 'tax_total', (string) $order->get_total_tax() ),
        ];
    }
}

Providers that need WooCommerce tax-rate keys can inject StoreAccountant\Order\Tax\OrderTaxRateResolver. The built-in extended provider uses it to combine configured WooCommerce tax rates with tax rates discovered from the exported orders.