<?php
namespace Misuzu;

use Index\CsrfToken;

final class CSRF {
    private static ?CsrfToken $instance = null;
    private static string $secretKey = '';

    public static function available(): bool {
        return self::$instance !== null;
    }

    public static function create(string $identity, ?string $secretKey = null): CsrfToken {
        if($secretKey === null)
            $secretKey = self::$secretKey;
        else
            self::$secretKey = $secretKey;

        return new CsrfToken($secretKey, $identity);
    }

    public static function init(string $secretKey, string $identity): void {
        self::$instance = self::create($identity, $secretKey);
    }

    public static function validate(string $token, int $tolerance = -1): bool {
        return self::$instance?->verifyToken($token, $tolerance) ?? false;
    }

    public static function token(): string {
        return self::$instance?->createToken() ?? '';
    }

    public static function validateRequest(int $tolerance = -1): bool {
        if(self::$instance === null)
            return false;

        $token = (string)filter_input(INPUT_POST, '_csrf');
        if(empty($token))
            $token = (string)filter_input(INPUT_GET, 'csrf');

        return self::$instance->verifyToken($token, $tolerance);
    }
}