package util

import (
	"errors"
	"time"

	"github.com/golang-jwt/jwt/v5"
)

var ApiSecret = "your-super-secret-key" // 预共享密钥
type Claims struct {
	UserID   uint   `json:"user_id"`
	Username string `json:"username"`
	jwt.RegisteredClaims
}

// GenerateToken 生成JWT Token
func GenerateToken(userID uint, username string) (string, error) {
	expirationTime := time.Now().Add(24 * 30 * time.Hour) // Token有效期24小时
	//expirationTime := time.Now().Add(1 * time.Second) // Token有效期24小时

	claims := &Claims{
		UserID:   userID,
		Username: username,
		RegisteredClaims: jwt.RegisteredClaims{
			ExpiresAt: jwt.NewNumericDate(expirationTime),
			IssuedAt:  jwt.NewNumericDate(time.Now()),
			NotBefore: jwt.NewNumericDate(time.Now()),
			Issuer:    "your-app-name",
		},
	}

	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
	tokenString, err := token.SignedString([]byte(ApiSecret))

	return tokenString, err
}

// ParseToken 解析JWT Token
func ParseToken(tokenStr string) (*Claims, error) {
	claims := &Claims{}

	token, err := jwt.ParseWithClaims(tokenStr, claims, func(token *jwt.Token) (interface{}, error) {
		return []byte(ApiSecret), nil
	})

	if err != nil {
		return nil, err
	}

	if !token.Valid {
		return nil, errors.New("invalid token")
	}

	return claims, nil
}