<?php
namespace League\Flysystem\UrlGeneration;
use InvalidArgumentException;
use League\Flysystem\Config;
use League\Flysystem\PathPrefixer;
use function array_map;
use function count;
use function crc32;
final class ShardedPrefixPublicUrlGenerator implements PublicUrlGenerator
{
/** @var PathPrefixer[] */
private array $prefixes;
private int $count;
/**
* @param string[] $prefixes
*/
public function __construct(array $prefixes)
{
$this->count = count($prefixes);
if ($this->count === 0) {
throw new InvalidArgumentException('At least one prefix is required.');
}
$this->prefixes = array_map(static fn (string $prefix) => new PathPrefixer($prefix, '/'), $prefixes);
}
public function publicUrl(string $path, Config $config): string
{
$index = abs(crc32($path)) % $this->count;
return $this->prefixes[$index]->prefixPath($path);
}
}