package util

import (
	"errors"
	"hr_receiver/models"
	"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"`
	Role       models.UserRole       `json:"role"`
	FlavorType models.UserFlavorType `json:"flavorType"`
	RegionIDs  []uint32              `json:"regionIds"`
	jwt.RegisteredClaims
}

// GenerateToken 生成JWT Token
func GenerateToken(user *models.User) (string, error) {
	now := time.Now()

	claims := &Claims{
		UserID:     user.ID,
		Username:   user.Username,
		Role:       user.Role,
		FlavorType: user.FlavorType,
		RegionIDs:  user.RegionIDs(),
		RegisteredClaims: jwt.RegisteredClaims{
			IssuedAt:  jwt.NewNumericDate(now),
			NotBefore: jwt.NewNumericDate(now),
			Issuer:    "your-app-name",
		},
	}
	if user.FlavorType != models.UserFlavorHeartRate {
		expirationTime := now.Add(24 * 30 * time.Hour)
		claims.ExpiresAt = jwt.NewNumericDate(expirationTime)
	}

	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
}

func IsTokenRevoked(user *models.User, claims *Claims) bool {
	if user == nil || claims == nil {
		return true
	}
	if user.TokenInvalidBefore <= 0 {
		return false
	}
	if claims.IssuedAt == nil {
		return true
	}
	return claims.IssuedAt.UnixMilli() <= user.TokenInvalidBefore
}