package jwt

import (
	"dy-admin/pkg/comopts"
	"github.com/gin-gonic/gin"
	"github.com/golang-jwt/jwt/v4"
	"github.com/pkg/errors"
	"time"
)

var (
	TokenExpired     = errors.New("Token is expired")
	TokenNotValidYet = errors.New("Token not active yet")
	TokenMalformed   = errors.New("That's not even a token")
	TokenInvalid     = errors.New("Couldn't handle this token:")
)

type CustomClaims struct {
	BaseClaims
	jwt.RegisteredClaims
}

type BaseClaims struct {
	UUID      string
	UserID    int
	Username  string
	NickName  string
	RoleIDs   []int
	DeptID    int
	RoleNames []string
}

type JWT struct {
	options *comopts.JwtOptions
}

func NewJWT(opt *comopts.JwtOptions) *JWT {
	return &JWT{
		options: opt,
	}
}

func (j *JWT) CreateClaims(baseClaims BaseClaims) CustomClaims {

	claims := CustomClaims{
		BaseClaims: baseClaims,
		RegisteredClaims: jwt.RegisteredClaims{
			NotBefore: jwt.NewNumericDate(time.Now()),                        // 签名生效时间
			ExpiresAt: jwt.NewNumericDate(time.Now().Add(j.options.Timeout)), // 过期时间 7天  配置文件
			Issuer:    j.options.Realm,                                       // 签名的发行者
		},
	}
	return claims
}

func (j *JWT) CreateToken(claims CustomClaims) (string, error) {
	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
	return token.SignedString([]byte(j.options.Key))
}

//func (j *JWT) CreateTokenByOldToken(oldToken string, claims CustomClaims) (string, error) {
//	v, err, _ := global.ConcurrencyControl.Do("JWT:"+oldToken, func() (interface{}, error) {
//		return j.CreateToken(claims)
//	})
//	return v.(string), err
//}

func (j *JWT) ParseToken(tokenString string) (*CustomClaims, error) {
	token, err := jwt.ParseWithClaims(tokenString, &CustomClaims{}, func(token *jwt.Token) (i interface{}, e error) {
		return []byte(j.options.Key), nil
	})
	if err != nil {
		if ve, ok := err.(*jwt.ValidationError); ok {
			if ve.Errors&jwt.ValidationErrorMalformed != 0 {
				return nil, TokenMalformed
			} else if ve.Errors&jwt.ValidationErrorExpired != 0 {
				// Token is expired
				return nil, TokenExpired
			} else if ve.Errors&jwt.ValidationErrorNotValidYet != 0 {
				return nil, TokenNotValidYet
			} else {
				return nil, TokenInvalid
			}
		}
	}
	if token != nil {
		if claims, ok := token.Claims.(*CustomClaims); ok && token.Valid {
			return claims, nil
		}
		return nil, TokenInvalid

	} else {
		return nil, TokenInvalid
	}
}

func (j *JWT) GetClaims(c *gin.Context) (*CustomClaims, error) {
	token := c.Request.Header.Get("Authorization")
	claims, err := j.ParseToken(token)
	if err != nil {
		return nil, err
	}
	return claims, err
}

func (j *JWT) GetUserID(c *gin.Context) int {
	if claims, exists := c.Get("claims"); !exists {
		if cl, err := j.GetClaims(c); err != nil {
			return 0
		} else {
			return cl.UserID
		}
	} else {
		waitUse := claims.(*CustomClaims)
		return waitUse.UserID
	}
}

func (j *JWT) GetDeptID(c *gin.Context) int {
	if claims, exists := c.Get("claims"); !exists {
		if cl, err := j.GetClaims(c); err != nil {
			return 0
		} else {
			return cl.DeptID
		}
	} else {
		waitUse := claims.(*CustomClaims)
		return waitUse.DeptID
	}
}

func (j *JWT) GetUserRoleIDs(c *gin.Context) []int {
	if claims, exists := c.Get("claims"); !exists {
		if cl, err := j.GetClaims(c); err != nil {
			return []int{}
		} else {
			return cl.RoleIDs
		}
	} else {
		waitUse := claims.(*CustomClaims)
		return waitUse.RoleIDs
	}
}

func (j *JWT) GetUserInfo(c *gin.Context) *CustomClaims {
	if claims, exists := c.Get("claims"); !exists {
		if cl, err := j.GetClaims(c); err != nil {
			return nil
		} else {
			return cl
		}
	} else {
		waitUse := claims.(*CustomClaims)
		return waitUse
	}
}