package auth

import (
	"crypto/sha256"
	"encoding/base64"
	"encoding/binary"
	"errors"
	"fmt"

	"github.com/golang-jwt/jwt"
	"github.com/zeromicro/go-zero/core/logx"
)

type IDTYPE int

const (
	// 白板用户, 以观众身份命名, 没有接收Cookie, 没有拿到guest_id的用户
	IDTYPE_Onlooker IDTYPE = 0
	// 登录用户
	IDTYPE_User IDTYPE = 1
	// 游客 接收授权拿到guest_id的用户
	IDTYPE_Guest IDTYPE = 2
)

type UserInfo struct {
	UserId  int64 `json:"user_id"`
	GuestId int64 `json:"guest_id"`
}

// GetIdType 用户确认用户身份类型
func (info *UserInfo) GetIdType() IDTYPE {
	if info.UserId != 0 {
		return IDTYPE_User
	}

	if info.GuestId != 0 {
		return IDTYPE_Guest
	}

	return IDTYPE_Onlooker
}

// IsUser 用户是不是登录用户
func (info *UserInfo) IsUser() bool {
	return info.UserId != 0
}

// IsGuest 用户是不是游客
func (info *UserInfo) IsGuest() bool {
	// 必须判断登录用户在前, 用户可能会携带以前是游客到注册的身份
	if info.UserId != 0 {
		return false
	}

	if info.GuestId != 0 {
		return true
	}

	return false
}

// IsOnlooker 白板用户: 非登录用户, 非游客, 判断为白板用户
func (info *UserInfo) IsOnlooker() bool {
	return info.UserId == 0 && info.GuestId == 0
}

type BackendUserInfo struct {
	UserId       int64 `json:"user_id"`
	DepartmentId int64 `json:"department_id"`
}

type OAuthInfo struct {
	Id       int64  `json:"id"`
	Platform string `json:"platform"`
}

// 获取登录信息
func GetUserInfoFormMapClaims(claims jwt.MapClaims) (*UserInfo, error) {
	userinfo := &UserInfo{}
	if userid, ok := claims["user_id"]; ok {
		uid, ok := userid.(float64)
		if !ok {
			err := errors.New(fmt.Sprint("parse uid form context err:", userid))
			logx.Error("parse uid form context err:", err)
			return nil, err
		}
		userinfo.UserId = int64(uid)
	} else {
		err := errors.New(`userid not in claims`)
		logx.Error(`userid not in claims`)
		return nil, err
	}

	if guestid, ok := claims["guest_id"]; ok {
		gid, ok := guestid.(float64)
		if !ok {
			err := errors.New(fmt.Sprint("parse guestid form context err:", guestid))
			logx.Error("parse guestid form context err:", err)
			return nil, err
		}
		userinfo.GuestId = int64(gid)
	} else {
		err := errors.New(`userid not in claims`)
		logx.Error(`userid not in claims`)
		return nil, err
	}

	return userinfo, nil
}

// GetBackendUserInfoFormMapClaims 获取后台登录信息
func GetBackendUserInfoFormMapClaims(claims jwt.MapClaims) (*BackendUserInfo, error) {
	userinfo := &BackendUserInfo{}
	if userid, ok := claims["user_id"]; ok {
		uid, ok := userid.(float64)
		if !ok {
			err := errors.New(fmt.Sprint("parse uid form context err:", userid))
			logx.Error("parse uid form context err:", err)
			return nil, err
		}
		userinfo.UserId = int64(uid)
	} else {
		err := errors.New(`userid not in claims`)
		logx.Error(`userid not in claims`)
		return nil, err
	}

	return userinfo, nil
}

// GenerateJwtTokenUint64 网站jwt token生成
func GenerateJwtTokenUint64(AccessSecret uint64, accessExpire, nowSec int64, userid int64, guestid int64) (string, error) {
	claims := make(jwt.MapClaims)
	claims["exp"] = nowSec + accessExpire
	claims["iat"] = nowSec

	if userid == 0 && guestid == 0 {
		err := errors.New("userid and guestid cannot be 0 at the same time")
		logx.Error(err)
		return "", err

	}
	claims["user_id"] = userid
	claims["guest_id"] = guestid

	token := jwt.New(jwt.SigningMethodHS256)
	token.Claims = claims

	key := make([]byte, 8)
	binary.BigEndian.PutUint64(key, AccessSecret)

	return token.SignedString(key)
}

// GenerateJwtToken 网站jwt token生成
func GenerateJwtToken(accessSecret *string, accessExpire, nowSec int64, userid int64, guestid int64) (string, error) {
	claims := make(jwt.MapClaims)
	claims["exp"] = nowSec + accessExpire
	claims["iat"] = nowSec

	if userid == 0 && guestid == 0 {
		err := errors.New("userid and guestid cannot be 0 at the same time")
		logx.Error(err)
		return "", err

	}
	claims["user_id"] = userid
	claims["guest_id"] = guestid

	token := jwt.New(jwt.SigningMethodHS256)
	token.Claims = claims
	return token.SignedString([]byte(*accessSecret))
}

// GenerateBackendJwtToken 后台jwt token生成
func GenerateBackendJwtToken(accessSecret *string, accessExpire, nowSec int64, userId int64, departmentId int64) (string, error) {
	claims := make(jwt.MapClaims)
	claims["exp"] = nowSec + accessExpire
	claims["iat"] = nowSec

	if userId == 0 {
		err := errors.New("userId  cannot be 0 at the same time")
		logx.Error(err)
		return "", err
	}
	claims["user_id"] = userId
	claims["department_id"] = departmentId

	token := jwt.New(jwt.SigningMethodHS256)
	token.Claims = claims
	return token.SignedString([]byte(*accessSecret))
}

func getJwtClaims(AuthKey string, AccessSecret *string) (jwt.MapClaims, error) {

	token, err := jwt.Parse(AuthKey, func(token *jwt.Token) (interface{}, error) {
		// 检查签名方法是否为 HS256
		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
			return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
		}
		// 返回用于验证签名的密钥
		return []byte(*AccessSecret), nil
	})
	if err != nil {
		return nil, errors.New(fmt.Sprint("Error parsing token:", err))
	}

	// 验证成功返回
	if claims, ok := token.Claims.(jwt.MapClaims); ok && token.Valid {
		return claims, nil
	}

	return nil, errors.New(fmt.Sprint("Invalid token", err))
}

func PasswordHash(pwd string) string {
	h := sha256.New()
	h.Write([]byte(pwd))
	return base64.RawURLEncoding.EncodeToString(h.Sum(nil))
}

func CheckValueRange[T comparable](v T, rangevalues ...T) bool {
	for _, rv := range rangevalues {
		if v == rv {
			return true
		}
	}
	return false
}

// GenerateRegisterToken 网站注册 token生成
func GenerateRegisterToken(accessSecret *string, accessExpire, nowSec int64, id int64, platform string) (string, error) {
	claims := make(jwt.MapClaims)
	claims["exp"] = nowSec + accessExpire
	claims["iat"] = nowSec

	if id == 0 {
		err := errors.New("userid and guestid cannot be 0 at the same time")
		logx.Error(err)
		return "", err

	}
	claims["id"] = id
	claims["platform"] = platform

	token := jwt.New(jwt.SigningMethodHS256)
	token.Claims = claims
	return token.SignedString([]byte(*accessSecret))
}

// GetRegisterFormMapClaims 获取注册唯一token标识登录信息
func GetRegisterFormMapClaims(claims jwt.MapClaims) (*OAuthInfo, error) {
	oauthinfo := &OAuthInfo{}
	if userid, ok := claims["id"]; ok {
		uid, ok := userid.(float64)
		if !ok {
			err := errors.New(fmt.Sprint("parse uid form context err:", userid))
			logx.Error("parse uid form context err:", err)
			return nil, err
		}
		oauthinfo.Id = int64(uid)
	} else {
		err := errors.New(`id not in claims`)
		logx.Error(`id not in claims`)
		return nil, err
	}

	if splatform, ok := claims["id"]; ok {
		platform, ok := splatform.(string)
		if !ok {
			err := errors.New(fmt.Sprint("parse uid form context err:", platform))
			logx.Error("parse uid form context err:", err)
			return nil, err
		}
		oauthinfo.Platform = platform
	} else {
		err := errors.New(`id not in claims`)
		logx.Error(`id not in claims`)
		return nil, err
	}

	return oauthinfo, nil
}

func getRegisterJwtClaims(Token string, AccessSecret *string) (jwt.MapClaims, error) {

	token, err := jwt.Parse(Token, func(token *jwt.Token) (interface{}, error) {
		// 检查签名方法是否为 HS256
		if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
			return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
		}
		// 返回用于验证签名的密钥
		return []byte(*AccessSecret), nil
	})
	if err != nil {
		return nil, errors.New(fmt.Sprint("Error parsing token:", err))
	}

	// 验证成功返回
	if claims, ok := token.Claims.(jwt.MapClaims); ok && token.Valid {
		return claims, nil
	}

	return nil, errors.New(fmt.Sprint("Invalid token", err))
}