<?php
declare(strict_types=1);

namespace Esun\CustomerVat\Model;

use Magento\Store\Model\StoreManagerInterface;

class TaxContextResolver
{
    public const MODE_NO_TAX = 'no_tax';
    public const MODE_EU_STANDARD = 'eu_standard_vat';
    public const MODE_EU_VAT_REGISTERED = 'eu_vat_registered';
    public const MODE_UK_STANDARD = 'uk_standard';

    public function __construct(
        private readonly StoreManagerInterface $storeManager,
        private readonly VatApplicationService $applications,
        private readonly EuCountries $euCountries
    ) {
    }

    public function resolve(int $storeId, int $customerId, string $shippingCountryId): TaxContext
    {
        $websiteCode = (string)$this->storeManager->getStore($storeId)->getWebsite()->getCode();
        if (in_array($websiteCode, ['uk', 'gb_site'], true)) {
            return new TaxContext(
                self::MODE_UK_STANDARD,
                20.0,
                EuCountries::toAppliedRate(20.0),
                false
            );
        }
        if (!in_array($websiteCode, ['eu', 'eu_site'], true)) {
            return new TaxContext(self::MODE_NO_TAX, 0.0, 0.0, false);
        }

        $countryId = strtoupper($shippingCountryId);
        if (!$this->euCountries->isEu($countryId)) {
            return new TaxContext(self::MODE_NO_TAX, 0.0, 0.0, false);
        }
        $nominalRate = $this->euCountries->getRate($countryId);
        $appliedRate = $this->euCountries->getAppliedRate($countryId);
        $approvedVat = $this->applications->findApproved($customerId, $countryId);
        if ($approvedVat !== null) {
            return new TaxContext(
                self::MODE_EU_VAT_REGISTERED,
                $nominalRate,
                $appliedRate,
                false,
                $approvedVat
            );
        }
        return new TaxContext(self::MODE_EU_STANDARD, $nominalRate, $appliedRate, false);
    }
}