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

namespace Index\Http\Headers;

use Index\Http\HttpHeader;

class CacheControlHeader {
    private array $params;

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

    public function getParams(): array {
        return $this->params;
    }

    public function hasParam(string $name): bool {
        return isset($this->params[strtolower($name)]);
    }

    public function getParam(string $name, int $filter = FILTER_DEFAULT, array|int $options = 0): mixed {
        $name = strtolower($name);
        if(!isset($this->params[$name]))
            return null;
        return filter_var($this->params[$name] ?? null, $filter, $options);
    }

    public static function parse(HttpHeader $header): CacheControlHeader {
        $raw = explode(',', strtolower($header->getFirstLine()));
        $params = [];

        foreach($raw as $param) {
            $parts = explode('=', $param, 2);
            $name = trim($parts[0]);
            $value = trim($parts[1] ?? '');
            if($value === '')
                $value = true;
            $params[$name] = $value;
        }

        return new CacheControlHeader($params);
    }
}