<?php

namespace App\Element\UseCases\UpdateElement;

use App\Element\Element;
use App\Element\ElementRepository;
use App\Exceptions\BadRequestException;
use App\Exceptions\NotFoundException;
use App\Shared\Files\Filesystem;

class UpdateShortPdfPath
{
    public function __construct(
        private ElementRepository $elementRepository,
        private Filesystem $filesystem,
    ) {
    }

    /**
     * @throws BadRequestException
     * @throws NotFoundException
     */
    public function execute(UpdateShortPdfPathRequest $request): Element
    {
        if ($request->id === null) {
            throw new BadRequestException('id is required');
        }

        if ($request->shortPdfPath === null) {
            throw new BadRequestException('shortPdfPath is required');
        }

        $element = $this->elementRepository->find($request->id);
        if ($element === null) {
            throw new NotFoundException('Element not found');
        }

        $shortPdfPath = $this->nullableString($request->shortPdfPath);
        if ($shortPdfPath === null) {
            $this->deleteManagedFile($element->getShortPdfPath());
        }

        $element->setShortPdfPath($shortPdfPath);

        return $this->elementRepository->update($element);
    }

    private function nullableString(string $value): ?string
    {
        if ($value === '') {
            return null;
        }

        return $value;
    }

    private function deleteManagedFile(?string $path): void
    {
        if ($path === null) {
            return;
        }

        $this->filesystem->delete($path);
    }
}