<?php

namespace App\State;

use ApiPlatform\Metadata\Operation;
use ApiPlatform\State\ProcessorInterface;
use App\Entity\Company;
use App\Entity\ContactLink;
use App\Entity\Domain;
use App\Entity\Employee;
use App\Entity\Location;
use App\Security\TenantContext;
use Symfony\Component\DependencyInjection\Attribute\AsDecorator;
use Symfony\Component\DependencyInjection\Attribute\AutowireDecorated;
use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;

/**
 * Stempelt beim Schreiben (POST/PATCH) den Mandanten automatisch aus dem
 * eingeloggten Kontext und verhindert Cross-Tenant-Referenzen.
 * Plattform-Admins sind nicht eingeschränkt.
 *
 * Dekoriert den Doctrine-Persist-Processor von API Platform.
 */
#[AsDecorator('api_platform.doctrine.orm.state.persist_processor')]
final class TenantStampProcessor implements ProcessorInterface
{
    public function __construct(
        #[AutowireDecorated]
        private readonly ProcessorInterface $inner,
        private readonly TenantContext $tenant,
    ) {
    }

    /**
     * @param array<string, mixed> $uriVariables
     * @param array<string, mixed> $context
     */
    public function process(mixed $data, Operation $operation, array $uriVariables = [], array $context = []): mixed
    {
        $this->stampAndValidate($data);

        return $this->inner->process($data, $operation, $uriVariables, $context);
    }

    private function stampAndValidate(mixed $data): void
    {
        // Plattform-Admins dürfen mandantenübergreifend schreiben
        if ($this->tenant->isPlatformAdmin()) {
            return;
        }

        $reseller = $this->tenant->getReseller();
        if (null === $reseller && $this->isTenantOwned($data)) {
            throw new AccessDeniedHttpException('Kein Mandantenkontext.');
        }

        match (true) {
            $data instanceof Company => $data->setReseller($reseller),
            $data instanceof Location,
            $data instanceof Domain => $this->assertCompany($data->getCompany()),
            $data instanceof Employee => $this->assertEmployee($data),
            $data instanceof ContactLink => $this->assertCompany($data->getEmployee()->getCompany()),
            default => null,
        };
    }

    private function assertEmployee(Employee $employee): void
    {
        $this->assertCompany($employee->getCompany());

        // Standort muss zur selben Firma gehören
        $location = $employee->getLocation();
        if (null !== $location && !$location->getCompany()->getId()->equals($employee->getCompany()->getId())) {
            throw new AccessDeniedHttpException('Standort gehört nicht zur Firma.');
        }
    }

    /** Prüft, dass die referenzierte Firma im Mandanten des Nutzers liegt. */
    private function assertCompany(Company $company): void
    {
        $reseller = $this->tenant->getReseller();
        if (null === $reseller || null === $company->getReseller()
            || !$company->getReseller()->getId()->equals($reseller->getId())) {
            throw new AccessDeniedHttpException('Firma gehört nicht zum eigenen Reseller.');
        }

        // Firmen-Admins dürfen nur in ihrer eigenen Firma schreiben
        $own = $this->tenant->getCompany();
        if (null !== $own && !$company->getId()->equals($own->getId())) {
            throw new AccessDeniedHttpException('Schreibzugriff nur auf die eigene Firma.');
        }
    }

    private function isTenantOwned(mixed $data): bool
    {
        return $data instanceof Company
            || $data instanceof Location
            || $data instanceof Domain
            || $data instanceof Employee
            || $data instanceof ContactLink;
    }
}