<?php

namespace app\api\service;

use Lcobucci\JWT\Configuration;
use Lcobucci\JWT\Signer\Hmac\Sha256;
use Lcobucci\JWT\Signer\Key\InMemory;
use DateTimeImmutable;
use Lcobucci\JWT\Token\Plain;
use Lcobucci\JWT\Validation\RequiredConstraintsViolated;
use Lcobucci\JWT\Validation\Constraint\SignedWith;

class LcJWTService
{
    protected static $url = 'https://douyin.xingtongworld.com/';
    /**
     * 配置秘钥加密
     * @return Configuration
     */
    public static function getConfig()
    {
        $configuration = Configuration::forSymmetricSigner(
        // You may use any HMAC variations (256, 384, and 512)
            new Sha256(),
            // replace the value below with a key of your own!
            InMemory::base64Encoded(config('jwt.secret'))
        // You may also override the JOSE encoder/decoder if needed by providing extra arguments here
        );
        return $configuration;
    }

    /**
     * 签发令牌
     */
    public static function createToken(int $userId,string $uname)
    {
        $config = self::getConfig();
        assert($config instanceof Configuration);

        $now = new DateTimeImmutable();

        $token = $config->builder()
            // 签发人
                        ->issuedBy(self::$url)
            // 受众
                        ->permittedFor(self::$url)
            // JWT ID 编号 唯一标识
                        ->identifiedBy($userId)
            // 签发时间
                        ->issuedAt($now)
            // 在1分钟后才可使用
            //            ->canOnlyBeUsedAfter($now->modify('+1 minute'))
            // 过期时间1小时
                        ->expiresAt($now->modify('+1 hour'))
            // 自定义uid 额外参数
                        ->withClaim('uid', $userId)
                        ->withClaim('name', $uname)
            // 自定义header 参数
                        ->withHeader('foo', 'bar')
            // 生成token
                        ->getToken($config->signer(), $config->signingKey());

        return $token->toString();
    }

    /**
     * 解析令牌
     */
    public static function parseToken(string $token)
    {
        $config = self::getConfig();
        assert($config instanceof Configuration);

        $token = $config->parser()->parse($token);

        assert($token instanceof Plain);

        return [
            'header' => $token->headers(),// Retrieves the token headers
            'claims' => $token->claims()// Retrieves the token claims
        ];
    }

    /**
     * 验证令牌
     */
    public static function validationToken(string $token, int $userId)
    {
        $config = self::getConfig();
        assert($config instanceof Configuration);

        $token = $config->parser()->parse($token);
        assert($token instanceof Plain);

        //Lcobucci\JWT\Validation\Constraint\IdentifiedBy: 验证jwt id是否匹配
        //Lcobucci\JWT\Validation\Constraint\IssuedBy: 验证签发人参数是否匹配
        //Lcobucci\JWT\Validation\Constraint\PermittedFor: 验证受众人参数是否匹配
        //Lcobucci\JWT\Validation\Constraint\RelatedTo: 验证自定义cliam参数是否匹配
        //Lcobucci\JWT\Validation\Constraint\SignedWith: 验证令牌是否已使用预期的签名者和密钥签名
        //Lcobucci\JWT\Validation\Constraint\ValidAt: 验证要求iat，nbf和exp（支持余地配置）

        //验证jwt id是否匹配
        $validate_jwt_id = new \Lcobucci\JWT\Validation\Constraint\IdentifiedBy($userId);
        $config->setValidationConstraints($validate_jwt_id);
        //验证签发人url是否正确
        $validate_issued = new \Lcobucci\JWT\Validation\Constraint\IssuedBy(self::$url);
        $config->setValidationConstraints($validate_issued);
        //验证客户端url是否匹配
        $validate_aud = new \Lcobucci\JWT\Validation\Constraint\PermittedFor(self::$url);
        $config->setValidationConstraints($validate_aud);

        //验证是否过期
        $timezone        = new \DateTimeZone('Asia/Shanghai');
        $now             = new \Lcobucci\Clock\SystemClock($timezone);
        $validate_jwt_at = new \Lcobucci\JWT\Validation\Constraint\ValidAt($now);
        $config->setValidationConstraints($validate_jwt_at);

        $constraints = $config->validationConstraints();

        try {
            $config->validator()->assert($token, ...$constraints);
            return true;
        } catch (RequiredConstraintsViolated $e) {
            // list of constraints violation exceptions:
            return $e->getMessage();
        }
    }
}