<?php

namespace app\utils;
use Firebase\JWT\JWT;
use Firebase\JWT\Key;

class JwtUtils
{
    private string $secret = "f4e2e52034348f86b67cde581c0f9eb5";
    private int $expire = 604800; // 单位：秒
    private string $header = "token";

    public function __construct()
    {
        $this->secret = base64_decode($this->secret);
    }


    /**
     * 生成 JWT Token
     */
    public function generateToken($userId, string $type): string
    {
        $now = time();
        $payload = [
            'sub' => (string)$userId,
            'type' => $type,
            'iat' => $now,
            'exp' => $now + $this->expire
        ];

        return JWT::encode($payload, $this->secret, 'HS512');
    }

    /**
     * 从 token 中解析出 Claims
     */
    public function getClaimByToken(string $token): ?object
    {
        try {
            return JWT::decode($token, new Key($this->secret, 'HS512'));
        } catch (\Exception $e) {
            error_log('Token 验证失败: ' . $e->getMessage());
            return null;
        }
    }

    /**
     * 判断 token 是否过期（通过传入的 exp 字段）
     */
    public function isTokenExpired(int $exp): bool
    {
        return $exp < time();
    }

    // Getter/Setter
    public function getSecret(): string
    {
        return $this->secret;
    }

    public function getExpire(): int
    {
        return $this->expire;
    }

    public function getHeader(): string
    {
        return $this->header;
    }

    public function setSecret(string $secret): void
    {
        $this->secret = $secret;
    }

    public function setExpire(int $expire): void
    {
        $this->expire = $expire;
    }

    public function setHeader(string $header): void
    {
        $this->header = $header;
    }
}