CaptchaBundle/Generator/ImageFileHandler.php

<?php

declare(strict_types=1);

namespace Gregwar\CaptchaBundle\Generator;

use Symfony\Component\Finder\Finder;

/**
 * Handles actions related to captcha image files including saving and garbage collection
 *
 * @author Gregwar <g.passault@gmail.com>
 * @author Jeremy Livingston <jeremy@quizzle.com>
 */
class ImageFileHandler
{
    /**
     * Name of folder for captcha images
     * @var string
     */
    protected $imageFolder;

    /**
     * Absolute path to public web folder
     * @var string
     */
    protected $webPath;

    /**
     * Frequency of garbage collection in fractions of 1
     * @var int
     */
    protected $gcFreq;

    /**
     * Maximum age of images in minutes
     * @var int
     */
    protected $expiration;

    /**
     * @param string $imageFolder
     * @param string $webPath
     * @param string $gcFreq
     * @param string $expiration
     */
    public function __construct(string $imageFolder, string $webPath, string $gcFreq, string $expiration)
    {
        $this->imageFolder = $imageFolder;
        $this->webPath= $webPath;
        $this->gcFreq = $gcFreq;
        $this->expiration = $expiration;
    }

    public function saveAsFile($contents):string
    {
        $this->createFolderIfMissing();

        $filename = md5(uniqid()) . '.jpg';
        $filePath = $this->webPath . '/' . $this->imageFolder . '/' . $filename;
        imagejpeg($contents, $filePath, 15);

        return '/' . $this->imageFolder . '/' . $filename;
    }

    public function collectGarbage(): bool
    {
        if (!mt_rand(1, $this->gcFreq) == 1) {
            return false;
        }

        $this->createFolderIfMissing();

        $finder = new Finder();
        $criteria = sprintf('<= now - %s minutes', $this->expiration);
        $finder->in($this->webPath . '/' . $this->imageFolder)
            ->date($criteria);

        foreach($finder->files() as $file) {
            unlink($file->getPathname());
        }

        return true;
    }

    protected function createFolderIfMissing(): void
    {
        if (!file_exists($this->webPath . '/' . $this->imageFolder)) {
            mkdir($this->webPath . '/' . $this->imageFolder, 0755);
        }
    }
}