package model

import (
	"errors"
	"fmt"
	"one-api/common"
	"strconv"
	"strings"
	"time"

	"gorm.io/gorm"
)

// User if you add sensitive fields, don't forget to clean them in setupLogin function.
// Otherwise, the sensitive information will be saved on local storage in plain text!
type User struct {
	Id               int            `json:"id"`
	Username         string         `json:"username" gorm:"unique;index" validate:"max=20"`
	Password         string         `json:"password" gorm:"not null;" validate:"min=8,max=30"`
	DisplayName      string         `json:"display_name" gorm:"index" validate:"max=20"`
	Role             int            `json:"role" gorm:"type:int;default:1"`   // admin, common
	Status           int            `json:"status" gorm:"type:int;default:1"` // enabled, disabled
	Email            string         `json:"email" gorm:"index" validate:"max=50"`
	GitHubId         string         `json:"github_id" gorm:"column:github_id;index"`
	WeChatId         string         `json:"wechat_id" gorm:"column:wechat_id;index"`
	TelegramId       string         `json:"telegram_id" gorm:"column:telegram_id;index"`
	VerificationCode string         `json:"verification_code" gorm:"-:all"`                                    // this field is only for Email verification, don't save it to database!
	AccessToken      string         `json:"access_token" gorm:"type:char(32);column:access_token;uniqueIndex"` // this token is for system management
	Quota            int            `json:"quota" gorm:"type:int;default:0"`
	UsedQuota        int            `json:"used_quota" gorm:"type:int;default:0;column:used_quota"` // used quota
	RequestCount     int            `json:"request_count" gorm:"type:int;default:0;"`               // request number
	Group            string         `json:"group" gorm:"type:varchar(64);default:'default'"`
	AffCode          string         `json:"aff_code" gorm:"type:varchar(32);column:aff_code;uniqueIndex"`
	AffCount         int            `json:"aff_count" gorm:"type:int;default:0;column:aff_count"`
	AffQuota         int            `json:"aff_quota" gorm:"type:int;default:0;column:aff_quota"`           // 邀请剩余额度
	AffHistoryQuota  int            `json:"aff_history_quota" gorm:"type:int;default:0;column:aff_history"` // 邀请历史额度
	InviterId        int            `json:"inviter_id" gorm:"type:int;column:inviter_id;index"`
	DeletedAt        gorm.DeletedAt `gorm:"index"`
}

// CheckUserExistOrDeleted check if user exist or deleted, if not exist, return false, nil, if deleted or exist, return true, nil
func CheckUserExistOrDeleted(username string, email string) (bool, error) {
	var user User

	// err := DB.Unscoped().First(&user, "username = ? or email = ?", username, email).Error
	// check email if empty
	var err error
	if email == "" {
		err = DB.Unscoped().First(&user, "username = ?", username).Error
	} else {
		err = DB.Unscoped().First(&user, "username = ? or email = ?", username, email).Error
	}
	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			// not exist, return false, nil
			return false, nil
		}
		// other error, return false, err
		return false, err
	}
	// exist, return true, nil
	return true, nil
}

func GetMaxUserId() int {
	var user User
	DB.Last(&user)
	return user.Id
}

func GetAllUsers(startIdx int, num int) (users []*User, err error) {
	err = DB.Unscoped().Order("id desc").Limit(num).Offset(startIdx).Omit("password").Find(&users).Error
	return users, err
}

func SearchUsers(keyword string, group string) ([]*User, error) {
	var users []*User
	var err error

	// 尝试将关键字转换为整数ID
	keywordInt, err := strconv.Atoi(keyword)
	if err == nil {
		// 如果转换成功，按照ID和可选的组别搜索用户
		query := DB.Unscoped().Omit("password").Where("`id` = ?", keywordInt)
		if group != "" {
			query = query.Where("`group` = ?", group) // 使用反引号包围group
		}
		err = query.Find(&users).Error
		if err != nil || len(users) > 0 {
			return users, err
		}
	}

	err = nil

	query := DB.Unscoped().Omit("password")
	likeCondition := "`username` LIKE ? OR `email` LIKE ? OR `display_name` LIKE ?"
	if group != "" {
		query = query.Where("("+likeCondition+") AND `group` = ?", "%"+keyword+"%", "%"+keyword+"%", "%"+keyword+"%", group)
	} else {
		query = query.Where(likeCondition, "%"+keyword+"%", "%"+keyword+"%", "%"+keyword+"%")
	}
	err = query.Find(&users).Error

	return users, err
}

func GetUserById(id int, selectAll bool) (*User, error) {
	if id == 0 {
		return nil, errors.New("id 为空！")
	}
	user := User{Id: id}
	var err error = nil
	if selectAll {
		err = DB.First(&user, "id = ?", id).Error
	} else {
		err = DB.Omit("password").First(&user, "id = ?", id).Error
	}
	return &user, err
}

func GetUserIdByAffCode(affCode string) (int, error) {
	if affCode == "" {
		return 0, errors.New("affCode 为空！")
	}
	var user User
	err := DB.Select("id").First(&user, "aff_code = ?", affCode).Error
	return user.Id, err
}

func DeleteUserById(id int) (err error) {
	if id == 0 {
		return errors.New("id 为空！")
	}
	user := User{Id: id}
	return user.Delete()
}

func HardDeleteUserById(id int) error {
	if id == 0 {
		return errors.New("id 为空！")
	}
	err := DB.Unscoped().Delete(&User{}, "id = ?", id).Error
	return err
}

func inviteUser(inviterId int) (err error) {
	user, err := GetUserById(inviterId, true)
	if err != nil {
		return err
	}
	user.AffCount++
	user.AffQuota += common.QuotaForInviter
	user.AffHistoryQuota += common.QuotaForInviter
	return DB.Save(user).Error
}

func (user *User) TransferAffQuotaToQuota(quota int) error {
	// 检查quota是否小于最小额度
	if float64(quota) < common.QuotaPerUnit {
		return fmt.Errorf("转移额度最小为%s！", common.LogQuota(int(common.QuotaPerUnit)))
	}

	// 开始数据库事务
	tx := DB.Begin()
	if tx.Error != nil {
		return tx.Error
	}
	defer tx.Rollback() // 确保在函数退出时事务能回滚

	// 加锁查询用户以确保数据一致性
	err := tx.Set("gorm:query_option", "FOR UPDATE").First(&user, user.Id).Error
	if err != nil {
		return err
	}

	// 再次检查用户的AffQuota是否足够
	if user.AffQuota < quota {
		return errors.New("邀请额度不足！")
	}

	// 更新用户额度
	user.AffQuota -= quota
	user.Quota += quota

	// 保存用户状态
	if err := tx.Save(user).Error; err != nil {
		return err
	}

	// 提交事务
	return tx.Commit().Error
}

func (user *User) Insert(inviterId int) error {
	var err error
	if user.Password != "" {
		user.Password, err = common.Password2Hash(user.Password)
		if err != nil {
			return err
		}
	}
	user.Quota = common.QuotaForNewUser
	user.AccessToken = common.GetUUID()
	user.AffCode = common.GetRandomString(4)
	result := DB.Create(user)
	if result.Error != nil {
		return result.Error
	}
	if common.QuotaForNewUser > 0 {
		RecordLog(user.Id, LogTypeSystem, fmt.Sprintf("新用户注册赠送 %s", common.LogQuota(common.QuotaForNewUser)))
	}
	if inviterId != 0 {
		if common.QuotaForInvitee > 0 {
			_ = IncreaseUserQuota(user.Id, common.QuotaForInvitee)
			RecordLog(user.Id, LogTypeSystem, fmt.Sprintf("使用邀请码赠送 %s", common.LogQuota(common.QuotaForInvitee)))
		}
		if common.QuotaForInviter > 0 {
			//_ = IncreaseUserQuota(inviterId, common.QuotaForInviter)
			RecordLog(inviterId, LogTypeSystem, fmt.Sprintf("邀请用户赠送 %s", common.LogQuota(common.QuotaForInviter)))
			_ = inviteUser(inviterId)
		}
	}
	return nil
}

func (user *User) Update(updatePassword bool) error {
	var err error
	if updatePassword {
		user.Password, err = common.Password2Hash(user.Password)
		if err != nil {
			return err
		}
	}
	newUser := *user
	DB.First(&user, user.Id)
	err = DB.Model(user).Updates(newUser).Error
	if err == nil {
		if common.RedisEnabled {
			_ = common.RedisSet(fmt.Sprintf("user_group:%d", user.Id), user.Group, time.Duration(UserId2GroupCacheSeconds)*time.Second)
			_ = common.RedisSet(fmt.Sprintf("user_quota:%d", user.Id), strconv.Itoa(user.Quota), time.Duration(UserId2QuotaCacheSeconds)*time.Second)
		}
	}
	return err
}

func (user *User) Edit(updatePassword bool) error {
	var err error
	if updatePassword {
		user.Password, err = common.Password2Hash(user.Password)
		if err != nil {
			return err
		}
	}
	newUser := *user
	updates := map[string]interface{}{
		"username":     newUser.Username,
		"display_name": newUser.DisplayName,
		"group":        newUser.Group,
		"quota":        newUser.Quota,
	}
	if updatePassword {
		updates["password"] = newUser.Password
	}
	DB.First(&user, user.Id)
	err = DB.Model(user).Updates(updates).Error
	if err == nil {
		if common.RedisEnabled {
			_ = common.RedisSet(fmt.Sprintf("user_group:%d", user.Id), user.Group, time.Duration(UserId2GroupCacheSeconds)*time.Second)
			_ = common.RedisSet(fmt.Sprintf("user_quota:%d", user.Id), strconv.Itoa(user.Quota), time.Duration(UserId2QuotaCacheSeconds)*time.Second)
		}
	}
	return err
}

func (user *User) Delete() error {
	if user.Id == 0 {
		return errors.New("id 为空！")
	}
	err := DB.Delete(user).Error
	return err
}

func (user *User) HardDelete() error {
	if user.Id == 0 {
		return errors.New("id 为空！")
	}
	err := DB.Unscoped().Delete(user).Error
	return err
}

// ValidateAndFill check password & user status
func (user *User) ValidateAndFill() (err error) {
	// When querying with struct, GORM will only query with non-zero fields,
	// that means if your field’s value is 0, '', false or other zero values,
	// it won’t be used to build query conditions
	password := user.Password
	if user.Username == "" || password == "" {
		return errors.New("用户名或密码为空")
	}
	DB.Where(User{Username: user.Username}).First(user)
	okay := common.ValidatePasswordAndHash(password, user.Password)
	if !okay || user.Status != common.UserStatusEnabled {
		return errors.New("用户名或密码错误，或用户已被封禁")
	}
	return nil
}

func (user *User) FillUserById() error {
	if user.Id == 0 {
		return errors.New("id 为空！")
	}
	DB.Where(User{Id: user.Id}).First(user)
	return nil
}

func (user *User) FillUserByEmail() error {
	if user.Email == "" {
		return errors.New("email 为空！")
	}
	DB.Where(User{Email: user.Email}).First(user)
	return nil
}

func (user *User) FillUserByGitHubId() error {
	if user.GitHubId == "" {
		return errors.New("GitHub id 为空！")
	}
	DB.Where(User{GitHubId: user.GitHubId}).First(user)
	return nil
}

func (user *User) FillUserByWeChatId() error {
	if user.WeChatId == "" {
		return errors.New("WeChat id 为空！")
	}
	DB.Where(User{WeChatId: user.WeChatId}).First(user)
	return nil
}

func (user *User) FillUserByUsername() error {
	if user.Username == "" {
		return errors.New("username 为空！")
	}
	DB.Where(User{Username: user.Username}).First(user)
	return nil
}

func (user *User) FillUserByTelegramId() error {
	if user.TelegramId == "" {
		return errors.New("Telegram id 为空！")
	}
	err := DB.Where(User{TelegramId: user.TelegramId}).First(user).Error
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return errors.New("该 Telegram 账户未绑定")
	}
	return nil
}

func IsEmailAlreadyTaken(email string) bool {
	return DB.Where("email = ?", email).Find(&User{}).RowsAffected == 1
}

func IsWeChatIdAlreadyTaken(wechatId string) bool {
	return DB.Where("wechat_id = ?", wechatId).Find(&User{}).RowsAffected == 1
}

func IsGitHubIdAlreadyTaken(githubId string) bool {
	return DB.Where("github_id = ?", githubId).Find(&User{}).RowsAffected == 1
}

func IsUsernameAlreadyTaken(username string) bool {
	return DB.Where("username = ?", username).Find(&User{}).RowsAffected == 1
}

func IsTelegramIdAlreadyTaken(telegramId string) bool {
	return DB.Where("telegram_id = ?", telegramId).Find(&User{}).RowsAffected == 1
}

func ResetUserPasswordByEmail(email string, password string) error {
	if email == "" || password == "" {
		return errors.New("邮箱地址或密码为空！")
	}
	hashedPassword, err := common.Password2Hash(password)
	if err != nil {
		return err
	}
	err = DB.Model(&User{}).Where("email = ?", email).Update("password", hashedPassword).Error
	return err
}

func IsAdmin(userId int) bool {
	if userId == 0 {
		return false
	}
	var user User
	err := DB.Where("id = ?", userId).Select("role").Find(&user).Error
	if err != nil {
		common.SysError("no such user " + err.Error())
		return false
	}
	return user.Role >= common.RoleAdminUser
}

func IsUserEnabled(userId int) (bool, error) {
	if userId == 0 {
		return false, errors.New("user id is empty")
	}
	var user User
	err := DB.Where("id = ?", userId).Select("status").Find(&user).Error
	if err != nil {
		return false, err
	}
	return user.Status == common.UserStatusEnabled, nil
}

func ValidateAccessToken(token string) (user *User) {
	if token == "" {
		return nil
	}
	token = strings.Replace(token, "Bearer ", "", 1)
	user = &User{}
	if DB.Where("access_token = ?", token).First(user).RowsAffected == 1 {
		return user
	}
	return nil
}

func GetUserQuota(id int) (quota int, err error) {
	err = DB.Model(&User{}).Where("id = ?", id).Select("quota").Find(&quota).Error
	if err != nil {
		if common.RedisEnabled {
			go cacheSetUserQuota(id, quota)
		}
	}
	return quota, err
}

func GetUserUsedQuota(id int) (quota int, err error) {
	err = DB.Model(&User{}).Where("id = ?", id).Select("used_quota").Find(&quota).Error
	return quota, err
}

func GetUserEmail(id int) (email string, err error) {
	err = DB.Model(&User{}).Where("id = ?", id).Select("email").Find(&email).Error
	return email, err
}

func GetUserGroup(id int) (group string, err error) {
	groupCol := "`group`"
	if common.UsingPostgreSQL {
		groupCol = `"group"`
	}

	err = DB.Model(&User{}).Where("id = ?", id).Select(groupCol).Find(&group).Error
	return group, err
}

func IncreaseUserQuota(id int, quota int) (err error) {
	if quota < 0 {
		return errors.New("quota 不能为负数！")
	}
	if common.BatchUpdateEnabled {
		addNewRecord(BatchUpdateTypeUserQuota, id, quota)
		return nil
	}
	return increaseUserQuota(id, quota)
}

func increaseUserQuota(id int, quota int) (err error) {
	err = DB.Model(&User{}).Where("id = ?", id).Update("quota", gorm.Expr("quota + ?", quota)).Error
	return err
}

func DecreaseUserQuota(id int, quota int) (err error) {
	if quota < 0 {
		return errors.New("quota 不能为负数！")
	}
	if common.BatchUpdateEnabled {
		addNewRecord(BatchUpdateTypeUserQuota, id, -quota)
		return nil
	}
	return decreaseUserQuota(id, quota)
}

func decreaseUserQuota(id int, quota int) (err error) {
	err = DB.Model(&User{}).Where("id = ?", id).Update("quota", gorm.Expr("quota - ?", quota)).Error
	return err
}

func GetRootUserEmail() (email string) {
	DB.Model(&User{}).Where("role = ?", common.RoleRootUser).Select("email").Find(&email)
	return email
}

func UpdateUserUsedQuotaAndRequestCount(id int, quota int) {
	if common.BatchUpdateEnabled {
		addNewRecord(BatchUpdateTypeUsedQuota, id, quota)
		addNewRecord(BatchUpdateTypeRequestCount, id, 1)
		return
	}
	updateUserUsedQuotaAndRequestCount(id, quota, 1)
}

func updateUserUsedQuotaAndRequestCount(id int, quota int, count int) {
	err := DB.Model(&User{}).Where("id = ?", id).Updates(
		map[string]interface{}{
			"used_quota":    gorm.Expr("used_quota + ?", quota),
			"request_count": gorm.Expr("request_count + ?", count),
		},
	).Error
	if err != nil {
		common.SysError("failed to update user used quota and request count: " + err.Error())
	}
}

func updateUserUsedQuota(id int, quota int) {
	err := DB.Model(&User{}).Where("id = ?", id).Updates(
		map[string]interface{}{
			"used_quota": gorm.Expr("used_quota + ?", quota),
		},
	).Error
	if err != nil {
		common.SysError("failed to update user used quota: " + err.Error())
	}
}

func updateUserRequestCount(id int, count int) {
	err := DB.Model(&User{}).Where("id = ?", id).Update("request_count", gorm.Expr("request_count + ?", count)).Error
	if err != nil {
		common.SysError("failed to update user request count: " + err.Error())
	}
}

func GetUsernameById(id int) (username string, err error) {
	err = DB.Model(&User{}).Where("id = ?", id).Select("username").Find(&username).Error
	return username, err
}
