<?php
// ContentLanguageHeader.php
// Created: 2022-02-14
// Updated: 2022-02-27

namespace Index\Http\Headers;

use Index\Http\HttpHeader;

class ContentLanguageHeader {
    private array $langs;

    public function __construct(array $langs) {
        $this->langs = $langs;
    }

    public function getLanguages(): array {
        return $this->langs;
    }

    public function hasLanguage(string $lang): bool {
        return in_array(strtolower($lang), $this->langs);
    }

    public static function parse(HttpHeader $header): ContentLanguageHeader {
        return new ContentLanguageHeader(
            array_unique(
                array_map(
                    fn($directive) => trim($directive),
                    explode(',', strtolower($header->getFirstLine()))
                )
            )
        );
    }
}