package auth

import (
	"errors"

	"mh-server/lib/status"
	"strings"

	"github.com/codinl/go-logger"
	"github.com/dgrijalva/jwt-go"
	"github.com/gin-gonic/gin"
)

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

//	jwtAppSecretKey   string
//	jwtAppRefreshKey  string
//	jwtAdminSecretKey string
//	expireTime        int
//	refreshPeriod     int

var jwtUserAccessKey string
var jwtUserRefreshKey string
var jwtUserAccessExpire int64
var jwtUserRefreshExpire int64

var jwtAdminAccessKey string
var jwtAdminRefreshKey string
var jwtAdminAccessExpire int64
var jwtAdminRefreshExpire int64

func Init(userAccessKey, userRefreshKey string, userAccessExpire int64, userRefreshExpire int64) {
	jwtUserAccessKey = userAccessKey
	jwtUserRefreshKey = userRefreshKey
	jwtUserAccessExpire = userAccessExpire
	jwtUserRefreshExpire = userRefreshExpire
}

func UserAccessAuth(c *gin.Context) {
	token := c.Request.Header.Get("Authorization")
	//logger.Infof("token= ", token)
	if s := strings.Split(token, " "); len(s) == 2 {
		token = s[1]
	}
	if token == "" || len(token) < 10 {
		RespJson(c, status.Unauthorized, nil)
		return
	}

	j := NewJWT(jwtUserAccessKey)
	claims, err := j.ParseToken(token)
	if err != nil {
		logger.Error(err)
		if err == TokenExpired {
			RespJson(c, status.AccessTokenExpired, nil)
		} else {
			RespJson(c, status.Unauthorized, nil)
		}
		return
	}

	c.Set("claims", claims)
}

func AdminAccessAuth(c *gin.Context) {
	token := c.Request.Header.Get("Authorization")
	if s := strings.Split(token, " "); len(s) == 2 {
		token = s[1]
	}
	if token == "" || len(token) < 10 {
		RespJson(c, status.Unauthorized, nil)
		return
	}

	j := NewJWT(jwtAdminAccessKey)
	claims, err := j.ParseToken(token)
	if err != nil {
		RespJson(c, status.Unauthorized, nil)
		return
	}

	c.Set("claims", claims)
}

func RespJson(c *gin.Context, code int, data interface{}) {
	result := struct {
		Code int         `json:"code"`
		Msg  string      `json:"msg"`
		Desc string      `json:"desc"`
		Data interface{} `json:"data"`
	}{
		Code: code,
		Desc: status.StatusDesc(code),
		Data: data,
	}
	c.JSON(status.OK, result)
	c.Abort()
}

type JWT struct {
	SigningKey []byte
}

type UserClaims struct {
	Uid uint32 `json:"uid"`
	jwt.StandardClaims
}

func NewJWT(key string) *JWT {
	return &JWT{
		[]byte(key),
	}
}

//func (j *JWT) CreateToken(user *UserClaims) (string, error) {
//	user.ExpiresAt = jwt.TimeFunc().Unix() + int64(jwtUserAccessExpire)
//	token := jwt.NewWithClaims(jwt.SigningMethodHS256, user)
//	return token.SignedString(j.SigningKey)
//}

func (j *JWT) CreateToken(uid uint32, key string, expire int64) (string, error) {
	user := UserClaims{
		Uid: uid,
	}
	user.ExpiresAt = jwt.TimeFunc().Unix() + expire
	token := jwt.NewWithClaims(jwt.SigningMethodHS256, user)
	return token.SignedString(key)
}

func (j *JWT) ParseToken(tokenString string) (*UserClaims, error) {
	token, err := jwt.ParseWithClaims(tokenString, &UserClaims{}, func(token *jwt.Token) (interface{}, error) {
		return j.SigningKey, nil
	})

	if err != nil {
		e := err.(*jwt.ValidationError)
		if e.Errors&jwt.ValidationErrorExpired != 0 {
			return nil, TokenExpired
		}
		return nil, err
	}

	if claims, ok := token.Claims.(*UserClaims); ok && token.Valid {
		return claims, nil
	} else {
		logger.Error(err)
	}

	return nil, TokenInvalid
}

func GetCurrentUser(c *gin.Context) *UserClaims {
	claims, ok := c.Get("claims")
	if !ok {
		return nil
	}
	user, ok := claims.(*UserClaims)
	if ok {
		return user
	}
	return nil
}

func CreateToken(uid uint32, key string, expire int64) (string, error) {
	user := UserClaims{
		Uid: uid,
	}
	user.ExpiresAt = jwt.TimeFunc().Unix() + expire
	token := jwt.NewWithClaims(jwt.SigningMethodHS256, user)
	return token.SignedString([]byte(key))
}

func CreateAccessToken(uid uint32) (string, error) {
	return CreateToken(uid, jwtUserAccessKey, jwtUserAccessExpire)
}

func CreateRefreshToken(uid uint32) (string, error) {
	return CreateToken(uid, jwtUserRefreshKey, jwtUserRefreshExpire)
}