<?php

declare(strict_types=1);

namespace Plugin\AzuraCastOnDemandHls\Cors;

use InvalidArgumentException;

/** Validates and canonicalizes web origins used by the HLS CORS allowlist. */
final class Origin
{
    public static function normalize(string $origin): string
    {
        $origin = trim($origin);
        if ('' === $origin || 'null' === strtolower($origin)) {
            throw new InvalidArgumentException('A CORS origin must be an absolute HTTP or HTTPS origin.');
        }

        $parts = parse_url($origin);
        if (false === $parts
            || !isset($parts['scheme'], $parts['host'])
            || isset($parts['user'], $parts['pass'], $parts['query'], $parts['fragment'])
            || (isset($parts['path']) && '/' !== $parts['path'])
        ) {
            throw new InvalidArgumentException(sprintf('Invalid CORS origin: %s', $origin));
        }

        $scheme = strtolower($parts['scheme']);
        $host = strtolower($parts['host']);
        if (!in_array($scheme, ['http', 'https'], true)
            || '' === $host
            || !preg_match('/^[a-z0-9.-]+$/D', $host)
        ) {
            throw new InvalidArgumentException(sprintf('Invalid CORS origin: %s', $origin));
        }

        $port = $parts['port'] ?? null;
        if (null !== $port && ($port < 1 || $port > 65535)) {
            throw new InvalidArgumentException(sprintf('Invalid CORS origin: %s', $origin));
        }

        if (('https' === $scheme && 443 === $port) || ('http' === $scheme && 80 === $port)) {
            $port = null;
        }

        return $scheme . '://' . $host . (null === $port ? '' : ':' . $port);
    }
}