package tokens

import (
	"fmt"
	"strconv"
	"strings"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/golang-jwt/jwt"
)

var API_SECRET = "wP3-sN6&gG4-lV8>gJ9)"

func GenerateToken(user_id uint, unique_Id string, Username string, Account string, EMAIL string) (string, error) {
	token_lifespan := 100
	fmt.Println("GenerateToken  user_id :", user_id, EMAIL)
	claims := jwt.MapClaims{}
	claims["authorized"] = true
	claims["user_id"] = user_id
	claims["unique_Id"] = unique_Id
	claims["Account"] = Account
	claims["user_name"] = Username
	claims["Email"] = EMAIL

	claims["exp"] = time.Now().Add(time.Hour * time.Duration(token_lifespan)).Unix()
	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
	tokenString, err := token.SignedString([]byte(API_SECRET))
	if err != nil {
		return "", err
	}
	fmt.Println("GenerateToken  tokenString :", tokenString)
	return tokenString, nil
}
func TokenValid(c *gin.Context) error {
	tokenString := ExtractToken(c)
	fmt.Println("TokenValid", tokenString)
	_, err := jwt.Parse(tokenString, func(token *jwt.Token) (any, error) {
		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
			fmt.Println(" TokenValid  jwt.Parse err ")
			return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
		}
		fmt.Println(" TokenValid(c *gin.Context)   ok")
		return []byte(API_SECRET), nil
	})
	if err != nil {
		return err
	}
	return nil
}

// 从请求头中获取token
func ExtractToken(c *gin.Context) string {
	bearerToken := c.GetHeader("Authorization")
	fmt.Println("ExtractToken =>BearerToken: ", bearerToken)
	if len(strings.Split(bearerToken, " ")) == 2 {
		return strings.Split(bearerToken, " ")[1]
	}
	fmt.Println("格式不正确")
	return ""
}

type UserClaims struct {
	UserId   uint
	UserName string
	Email    string
}

// 从jwt中解析出user_id
func ExtractTokenID(c *gin.Context) (*UserClaims, error) {
	tokenString := ExtractToken(c)
	token, err := jwt.Parse(tokenString, func(token *jwt.Token) (any, error) {
		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
			return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
		}
		return []byte(API_SECRET), nil
	})

	if err != nil {
		return nil, err
	}

	claims, ok := token.Claims.(jwt.MapClaims)
	// 如果jwt有效，将user_id转换为浮点数字符串，然后再转换为 uint32

	if ok && token.Valid {
		uid, err := strconv.ParseUint(fmt.Sprintf("%.0f", claims["user_id"]), 10, 32)
		userName, ok := claims["user_name"].(string)
		if !ok {
			return nil, fmt.Errorf("user_name is not a string")
		}
		EMAIL, ok := claims["Email"].(string)
		if !ok {
			return nil, fmt.Errorf("Email is not a string")
		}
		fmt.Println("userName: ", userName)
		fmt.Println("EMAIL: ", EMAIL)
		if err != nil {
			return nil, err
		}
		user := &UserClaims{
			UserId:   uint(uid),
			UserName: userName,
			Email:    EMAIL,
		}
		return user, nil
	}

	return nil, fmt.Errorf("token is invalid")
}