// Copyright 2014 The Gogs Authors. All rights reserved.
// Copyright 2019 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT

package user

import (
	"context"
	"encoding/hex"
	"fmt"
	"mime"
	"net/mail"
	"net/url"
	"path/filepath"
	"regexp"
	"strings"
	"sync"
	"time"
	"unicode"

	_ "image/jpeg" // Needed for jpeg support

	"code.gitea.io/gitea/models/auth"
	"code.gitea.io/gitea/models/db"
	"code.gitea.io/gitea/modules/auth/openid"
	"code.gitea.io/gitea/modules/auth/password/hash"
	"code.gitea.io/gitea/modules/base"
	"code.gitea.io/gitea/modules/container"
	"code.gitea.io/gitea/modules/git"
	"code.gitea.io/gitea/modules/httplib"
	"code.gitea.io/gitea/modules/log"
	"code.gitea.io/gitea/modules/optional"
	"code.gitea.io/gitea/modules/setting"
	"code.gitea.io/gitea/modules/structs"
	"code.gitea.io/gitea/modules/timeutil"
	"code.gitea.io/gitea/modules/util"
	"code.gitea.io/gitea/modules/validation"

	"golang.org/x/text/runes"
	"golang.org/x/text/transform"
	"golang.org/x/text/unicode/norm"
	"xorm.io/builder"
)

// UserType defines the user type
type UserType int //revive:disable-line:exported

const (
	// UserTypeIndividual defines an individual user
	UserTypeIndividual UserType = iota // Historic reason to make it starts at 0.

	// UserTypeOrganization defines an organization
	UserTypeOrganization // 1

	// UserTypeUserReserved reserves a (non-existing) user, i.e. to prevent a spam user from re-registering after being deleted, or to reserve the name until the user is actually created later on
	UserTypeUserReserved // 2

	// UserTypeOrganizationReserved reserves a (non-existing) organization, to be used in combination with UserTypeUserReserved
	UserTypeOrganizationReserved // 3

	// UserTypeBot defines a bot user
	UserTypeBot // 4

	// UserTypeRemoteUser defines a remote user for federated users
	UserTypeRemoteUser // 5
)

const (
	// EmailNotificationsEnabled indicates that the user would like to receive all email notifications except your own
	EmailNotificationsEnabled = "enabled"
	// EmailNotificationsOnMention indicates that the user would like to be notified via email when mentioned.
	EmailNotificationsOnMention = "onmention"
	// EmailNotificationsDisabled indicates that the user would not like to be notified via email.
	EmailNotificationsDisabled = "disabled"
	// EmailNotificationsAndYourOwn indicates that the user would like to receive all email notifications and your own
	EmailNotificationsAndYourOwn = "andyourown"
)

// User represents the object of individual and member of organization.
type User struct {
	ID        int64  `xorm:"pk autoincr"`
	LowerName string `xorm:"UNIQUE NOT NULL"`
	Name      string `xorm:"UNIQUE NOT NULL"`
	FullName  string
	// Email is the primary email address (to be used for communication)
	Email                        string `xorm:"NOT NULL"`
	KeepEmailPrivate             bool
	EmailNotificationsPreference string `xorm:"VARCHAR(20) NOT NULL DEFAULT 'enabled'"`
	Passwd                       string `xorm:"NOT NULL"`
	PasswdHashAlgo               string `xorm:"NOT NULL DEFAULT 'argon2'"`

	// MustChangePassword is an attribute that determines if a user
	// is to change their password after registration.
	MustChangePassword bool `xorm:"NOT NULL DEFAULT false"`

	LoginType   auth.Type
	LoginSource int64 `xorm:"NOT NULL DEFAULT 0"`
	LoginName   string
	Type        UserType
	Location    string
	Website     string
	Rands       string `xorm:"VARCHAR(32)"`
	Salt        string `xorm:"VARCHAR(32)"`
	Language    string `xorm:"VARCHAR(5)"`
	Description string

	CreatedUnix   timeutil.TimeStamp `xorm:"INDEX created"`
	UpdatedUnix   timeutil.TimeStamp `xorm:"INDEX updated"`
	LastLoginUnix timeutil.TimeStamp `xorm:"INDEX"`

	// Remember visibility choice for convenience, true for private
	LastRepoVisibility bool
	// Maximum repository creation limit, -1 means use global default
	MaxRepoCreation int `xorm:"NOT NULL DEFAULT -1"`

	// IsActive true: primary email is activated, user can access Web UI and Git SSH.
	// false: an inactive user can only log in Web UI for account operations (ex: activate the account by email), no other access.
	IsActive bool `xorm:"INDEX"`
	// the user is a Gitea admin, who can access all repositories and the admin pages.
	IsAdmin bool
	// true: the user is only allowed to see organizations/repositories that they has explicit rights to.
	// (ex: in private Gitea instances user won't be allowed to see even organizations/repositories that are set as public)
	IsRestricted bool `xorm:"NOT NULL DEFAULT false"`

	AllowGitHook            bool
	AllowImportLocal        bool // Allow migrate repository by local path
	AllowCreateOrganization bool `xorm:"DEFAULT true"`

	// true: the user is not allowed to log in Web UI. Git/SSH access could still be allowed (please refer to Git/SSH access related code/documents)
	ProhibitLogin bool `xorm:"NOT NULL DEFAULT false"`

	// Avatar
	Avatar          string `xorm:"VARCHAR(2048) NOT NULL"`
	AvatarEmail     string `xorm:"NOT NULL"`
	UseCustomAvatar bool

	// Counters
	NumFollowers int
	NumFollowing int `xorm:"NOT NULL DEFAULT 0"`
	NumStars     int
	NumRepos     int

	// For organization
	NumTeams                  int
	NumMembers                int
	Visibility                structs.VisibleType `xorm:"NOT NULL DEFAULT 0"`
	RepoAdminChangeTeamAccess bool                `xorm:"NOT NULL DEFAULT false"`

	// Preferences
	DiffViewStyle       string `xorm:"NOT NULL DEFAULT ''"`
	Theme               string `xorm:"NOT NULL DEFAULT ''"`
	KeepActivityPrivate bool   `xorm:"NOT NULL DEFAULT false"`
}

// Meta defines the meta information of a user, to be stored in the K/V table
type Meta struct {
	// Store the initial registration of the user, to aid in spam prevention
	// Ensure that one IP isn't creating many accounts (following mediawiki approach)
	InitialIP        string
	InitialUserAgent string
}

func init() {
	db.RegisterModel(new(User))
}

// SearchOrganizationsOptions options to filter organizations
type SearchOrganizationsOptions struct {
	db.ListOptions
	All bool
}

func (u *User) LogString() string {
	if u == nil {
		return "<User nil>"
	}
	return fmt.Sprintf("<User %d:%s>", u.ID, u.Name)
}

// BeforeUpdate is invoked from XORM before updating this object.
func (u *User) BeforeUpdate() {
	if u.MaxRepoCreation < -1 {
		u.MaxRepoCreation = -1
	}

	// FIXME: this email doesn't need to be in lowercase, because the emails are mainly managed by the email table with lower_email field
	// This trick could be removed in new releases to display the user inputed email as-is.
	u.Email = strings.ToLower(u.Email)
	if !u.IsOrganization() {
		if len(u.AvatarEmail) == 0 {
			u.AvatarEmail = u.Email
		}
	}

	u.LowerName = strings.ToLower(u.Name)
	u.Location = util.TruncateRunes(u.Location, 255)
	u.Website = util.TruncateRunes(u.Website, 255)
	u.Description = util.TruncateRunes(u.Description, 255)
}

// AfterLoad is invoked from XORM after filling all the fields of this object.
func (u *User) AfterLoad() {
	if u.Theme == "" {
		u.Theme = setting.UI.DefaultTheme
	}
}

// SetLastLogin set time to last login
func (u *User) SetLastLogin() {
	u.LastLoginUnix = timeutil.TimeStampNow()
}

// GetPlaceholderEmail returns an noreply email
func (u *User) GetPlaceholderEmail() string {
	return fmt.Sprintf("%s@%s", u.LowerName, setting.Service.NoReplyAddress)
}

// GetEmail returns a noreply email, if the user has set to keep his
// email address private, otherwise the primary email address.
func (u *User) GetEmail() string {
	if u.KeepEmailPrivate {
		return u.GetPlaceholderEmail()
	}
	return u.Email
}

// GetAllUsers returns a slice of all individual users found in DB.
func GetAllUsers(ctx context.Context) ([]*User, error) {
	users := make([]*User, 0)
	return users, db.GetEngine(ctx).OrderBy("id").Where("type = ?", UserTypeIndividual).Find(&users)
}

// IsLocal returns true if user login type is LoginPlain.
func (u *User) IsLocal() bool {
	return u.LoginType <= auth.Plain
}

// IsOAuth2 returns true if user login type is LoginOAuth2.
func (u *User) IsOAuth2() bool {
	return u.LoginType == auth.OAuth2
}

// MaxCreationLimit returns the number of repositories a user is allowed to create
func (u *User) MaxCreationLimit() int {
	if u.MaxRepoCreation <= -1 {
		return setting.Repository.MaxCreationLimit
	}
	return u.MaxRepoCreation
}

// CanCreateRepoIn checks whether the doer(u) can create a repository in the owner
// NOTE: functions calling this assume a failure due to repository count limit; it ONLY checks the repo number LIMIT, if new checks are added, those functions should be revised
func (u *User) CanCreateRepoIn(owner *User) bool {
	if u.IsAdmin {
		return true
	}
	const noLimit = -1
	if owner.MaxRepoCreation == noLimit {
		if setting.Repository.MaxCreationLimit == noLimit {
			return true
		}
		return owner.NumRepos < setting.Repository.MaxCreationLimit
	}
	return owner.NumRepos < owner.MaxRepoCreation
}

// CanCreateOrganization returns true if user can create organisation.
func (u *User) CanCreateOrganization() bool {
	return u.IsAdmin || (u.AllowCreateOrganization && !setting.Admin.DisableRegularOrgCreation)
}

// CanEditGitHook returns true if user can edit Git hooks.
func (u *User) CanEditGitHook() bool {
	return !setting.DisableGitHooks && (u.IsAdmin || u.AllowGitHook)
}

// CanForkRepoIn ONLY checks repository count limit
func (u *User) CanForkRepoIn(owner *User) bool {
	if setting.Repository.AllowForkWithoutMaximumLimit {
		return true
	}
	return u.CanCreateRepoIn(owner)
}

// CanImportLocal returns true if user can migrate repository by local path.
func (u *User) CanImportLocal() bool {
	if !setting.ImportLocalPaths || u == nil {
		return false
	}
	return u.IsAdmin || u.AllowImportLocal
}

// DashboardLink returns the user dashboard page link.
func (u *User) DashboardLink() string {
	if u.IsOrganization() {
		return u.OrganisationLink() + "/dashboard"
	}
	return setting.AppSubURL + "/"
}

// HomeLink returns the user or organization home page link.
func (u *User) HomeLink() string {
	return setting.AppSubURL + "/" + url.PathEscape(u.Name)
}

// HTMLURL returns the user or organization's full link.
func (u *User) HTMLURL(ctx context.Context) string {
	return httplib.MakeAbsoluteURL(ctx, u.HomeLink())
}

// OrganisationLink returns the organization sub page link.
func (u *User) OrganisationLink() string {
	return setting.AppSubURL + "/org/" + url.PathEscape(u.Name)
}

// GetUserFollowers returns range of user's followers.
func GetUserFollowers(ctx context.Context, u, viewer *User, listOptions db.ListOptions) ([]*User, int64, error) {
	sess := db.GetEngine(ctx).
		Select("`user`.*").
		Join("LEFT", "follow", "`user`.id=follow.user_id").
		Where("follow.follow_id=?", u.ID).
		And("`user`.type=?", UserTypeIndividual).
		And(isUserVisibleToViewerCond(viewer))

	if listOptions.Page > 0 {
		sess = db.SetSessionPagination(sess, &listOptions)

		users := make([]*User, 0, listOptions.PageSize)
		count, err := sess.FindAndCount(&users)
		return users, count, err
	}

	users := make([]*User, 0, 8)
	count, err := sess.FindAndCount(&users)
	return users, count, err
}

// GetUserFollowing returns range of user's following.
func GetUserFollowing(ctx context.Context, u, viewer *User, listOptions db.ListOptions) ([]*User, int64, error) {
	sess := db.GetEngine(ctx).
		Select("`user`.*").
		Join("LEFT", "follow", "`user`.id=follow.follow_id").
		Where("follow.user_id=?", u.ID).
		And("`user`.type IN (?, ?)", UserTypeIndividual, UserTypeOrganization).
		And(isUserVisibleToViewerCond(viewer))

	if listOptions.Page > 0 {
		sess = db.SetSessionPagination(sess, &listOptions)

		users := make([]*User, 0, listOptions.PageSize)
		count, err := sess.FindAndCount(&users)
		return users, count, err
	}

	users := make([]*User, 0, 8)
	count, err := sess.FindAndCount(&users)
	return users, count, err
}

// NewGitSig generates and returns the signature of given user.
func (u *User) NewGitSig() *git.Signature {
	return &git.Signature{
		Name:  u.GitName(),
		Email: u.GetEmail(),
		When:  time.Now(),
	}
}

// SetPassword hashes a password using the algorithm defined in the config value of PASSWORD_HASH_ALGO
// change passwd, salt and passwd_hash_algo fields
func (u *User) SetPassword(passwd string) (err error) {
	if u.Salt, err = GetUserSalt(); err != nil {
		return err
	}
	if u.Passwd, err = hash.Parse(setting.PasswordHashAlgo).Hash(passwd, u.Salt); err != nil {
		return err
	}
	u.PasswdHashAlgo = setting.PasswordHashAlgo

	return nil
}

// ValidatePassword checks if the given password matches the one belonging to the user.
func (u *User) ValidatePassword(passwd string) bool {
	return hash.Parse(u.PasswdHashAlgo).VerifyPassword(passwd, u.Passwd, u.Salt)
}

// IsPasswordSet checks if the password is set or left empty
// TODO: It's better to clarify the "password" behavior for different types (individual, bot)
func (u *User) IsPasswordSet() bool {
	return u.Passwd != ""
}

// IsOrganization returns true if user is actually an organization.
func (u *User) IsOrganization() bool {
	return u.Type == UserTypeOrganization
}

// IsIndividual returns true if user is actually a individual user.
func (u *User) IsIndividual() bool {
	return u.Type == UserTypeIndividual
}

// IsTypeBot returns whether the user is of type bot
func (u *User) IsTypeBot() bool {
	return u.Type == UserTypeBot
}

// IsTokenAccessAllowed returns whether the user is an individual or a bot (which allows for token access)
func (u *User) IsTokenAccessAllowed() bool {
	return u.Type == UserTypeIndividual || u.Type == UserTypeBot
}

// DisplayName returns full name if it's not empty,
// returns username otherwise.
func (u *User) DisplayName() string {
	trimmed := strings.TrimSpace(u.FullName)
	if len(trimmed) > 0 {
		return trimmed
	}
	return u.Name
}

// EmailTo returns a string suitable to be put into a e-mail `To:` header.
func (u *User) EmailTo() string {
	sanitizedDisplayName := globalVars().emailToReplacer.Replace(u.DisplayName())

	// should be an edge case but nice to have
	if sanitizedDisplayName == u.Email {
		return u.Email
	}

	to := fmt.Sprintf("%s <%s>", sanitizedDisplayName, u.Email)
	add, err := mail.ParseAddress(to)
	if err != nil {
		return u.Email
	}

	return fmt.Sprintf("%s <%s>", mime.QEncoding.Encode("utf-8", add.Name), add.Address)
}

// GetDisplayName returns full name if it's not empty and DEFAULT_SHOW_FULL_NAME is set,
// returns username otherwise.
func (u *User) GetDisplayName() string {
	if setting.UI.DefaultShowFullName {
		trimmed := strings.TrimSpace(u.FullName)
		if len(trimmed) > 0 {
			return trimmed
		}
	}
	return u.Name
}

// GetCompleteName returns the full name and username in the form of
// "Full Name (username)" if full name is not empty, otherwise it returns
// "username".
func (u *User) GetCompleteName() string {
	trimmedFullName := strings.TrimSpace(u.FullName)
	if len(trimmedFullName) > 0 {
		return fmt.Sprintf("%s (%s)", trimmedFullName, u.Name)
	}
	return u.Name
}

func gitSafeName(name string) string {
	return strings.TrimSpace(strings.NewReplacer("\n", "", "<", "", ">", "").Replace(name))
}

// GitName returns a git safe name
func (u *User) GitName() string {
	gitName := gitSafeName(u.FullName)
	if len(gitName) > 0 {
		return gitName
	}
	// Although u.Name should be safe if created in our system
	// LDAP users may have bad names
	gitName = gitSafeName(u.Name)
	if len(gitName) > 0 {
		return gitName
	}
	// Totally pathological name so it's got to be:
	return fmt.Sprintf("user-%d", u.ID)
}

// ShortName ellipses username to length
func (u *User) ShortName(length int) string {
	if setting.UI.DefaultShowFullName && len(u.FullName) > 0 {
		return util.EllipsisDisplayString(u.FullName, length)
	}
	return util.EllipsisDisplayString(u.Name, length)
}

// IsMailable checks if a user is eligible
// to receive emails.
func (u *User) IsMailable() bool {
	return u.IsActive
}

// IsUserExist checks if given username exist,
// the username should be non-cased unique.
// If uid is presented, then check will rule out that one,
// it is used when update a username in settings page.
func IsUserExist(ctx context.Context, uid int64, name string) (bool, error) {
	if len(name) == 0 {
		return false, nil
	}
	return db.GetEngine(ctx).
		Where("id!=?", uid).
		Get(&User{LowerName: strings.ToLower(name)})
}

// SaltByteLength as of the beginning of 2022, it is recommended to use at least
// 64 bits of salt, but NIST is already recommending to use to 128 bits.
// (16 bytes = 16 * 8 = 128 bits)
const SaltByteLength = 16

// GetUserSalt returns a random user salt token.
func GetUserSalt() (string, error) {
	rBytes, err := util.CryptoRandomBytes(SaltByteLength)
	if err != nil {
		return "", err
	}
	// Returns a 32-byte long string.
	return hex.EncodeToString(rBytes), nil
}

type globalVarsStruct struct {
	customCharsReplacement *strings.Replacer
	removeCharsRE          *regexp.Regexp
	transformDiacritics    transform.Transformer
	replaceCharsHyphenRE   *regexp.Regexp
	emailToReplacer        *strings.Replacer
	emailRegexp            *regexp.Regexp
	systemUserNewFuncs     map[int64]func() *User
}

var globalVars = sync.OnceValue(func() *globalVarsStruct {
	return &globalVarsStruct{
		// Note: The set of characters here can safely expand without a breaking change,
		// but characters removed from this set can cause user account linking to break
		customCharsReplacement: strings.NewReplacer("Æ", "AE"),

		removeCharsRE:        regexp.MustCompile("['`´]"),
		transformDiacritics:  transform.Chain(norm.NFD, runes.Remove(runes.In(unicode.Mn)), norm.NFC),
		replaceCharsHyphenRE: regexp.MustCompile(`[\s~+]`),

		emailToReplacer: strings.NewReplacer(
			"\n", "",
			"\r", "",
			"<", "",
			">", "",
			",", "",
			":", "",
			";", "",
		),
		emailRegexp: regexp.MustCompile("^[a-zA-Z0-9.!#$%&'*+-/=?^_`{|}~]*@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$"),

		systemUserNewFuncs: map[int64]func() *User{
			GhostUserID:   NewGhostUser,
			ActionsUserID: NewActionsUser,
		},
	}
})

// NormalizeUserName only takes the name part if it is an email address, transforms it diacritics to ASCII characters.
// It returns a string with the single-quotes removed, and any other non-supported username characters are replaced with a `-` character
func NormalizeUserName(s string) (string, error) {
	vars := globalVars()
	s, _, _ = strings.Cut(s, "@")
	strDiacriticsRemoved, n, err := transform.String(vars.transformDiacritics, vars.customCharsReplacement.Replace(s))
	if err != nil {
		return "", fmt.Errorf("failed to normalize the string of provided username %q at position %d", s, n)
	}
	return vars.replaceCharsHyphenRE.ReplaceAllLiteralString(vars.removeCharsRE.ReplaceAllLiteralString(strDiacriticsRemoved, ""), "-"), nil
}

var (
	reservedUsernames = []string{
		".",
		"..",
		".well-known",

		"api",     // gitea api
		"metrics", // prometheus metrics api
		"v2",      // container registry api

		"assets",      // static asset files
		"attachments", // issue attachments

		"avatar",  // avatar by email hash
		"avatars", // user avatars by file name
		"repo-avatars",

		"captcha",
		"login", // oauth2 login
		"org",   // org create/manage, or "/org/{org}", BUT if an org is named as "invite" then it goes wrong
		"repo",  // repo create/migrate, etc
		"user",  // user login/activate/settings, etc

		"explore",
		"issues",
		"pulls",
		"milestones",
		"notifications",

		"favicon.ico",
		"manifest.json", // web app manifests
		"robots.txt",    // search engine robots
		"sitemap.xml",   // search engine sitemap
		"ssh_info",      // agit info
		"swagger.v1.json",

		"ghost",         // reserved name for deleted users (id: -1)
		"gitea-actions", // gitea builtin user (id: -2)
	}

	// These names are reserved for user accounts: user's keys, user's rss feed, user's avatar, etc.
	// DO NOT add any new stuff! The paths with these names are processed by `/{username}` handler (UsernameSubRoute) manually.
	reservedUserPatterns = []string{"*.keys", "*.gpg", "*.rss", "*.atom", "*.png"}
)

// IsUsableUsername returns an error when a username is reserved
func IsUsableUsername(name string) error {
	// Validate username make sure it satisfies requirement.
	if !validation.IsValidUsername(name) {
		// Note: usually this error is normally caught up earlier in the UI
		return db.ErrNameCharsNotAllowed{Name: name}
	}
	return db.IsUsableName(reservedUsernames, reservedUserPatterns, name)
}

// CreateUserOverwriteOptions are an optional options who overwrite system defaults on user creation
type CreateUserOverwriteOptions struct {
	KeepEmailPrivate             optional.Option[bool]
	Visibility                   *structs.VisibleType
	AllowCreateOrganization      optional.Option[bool]
	EmailNotificationsPreference *string
	MaxRepoCreation              *int
	Theme                        *string
	IsRestricted                 optional.Option[bool]
	IsActive                     optional.Option[bool]
}

// CreateUser creates record of a new user.
func CreateUser(ctx context.Context, u *User, meta *Meta, overwriteDefault ...*CreateUserOverwriteOptions) (err error) {
	return createUser(ctx, u, meta, false, overwriteDefault...)
}

// AdminCreateUser is used by admins to manually create users
func AdminCreateUser(ctx context.Context, u *User, meta *Meta, overwriteDefault ...*CreateUserOverwriteOptions) (err error) {
	return createUser(ctx, u, meta, true, overwriteDefault...)
}

// createUser creates record of a new user.
func createUser(ctx context.Context, u *User, meta *Meta, createdByAdmin bool, overwriteDefault ...*CreateUserOverwriteOptions) (err error) {
	if err = IsUsableUsername(u.Name); err != nil {
		return err
	}

	// set system defaults
	u.KeepEmailPrivate = setting.Service.DefaultKeepEmailPrivate
	u.Visibility = setting.Service.DefaultUserVisibilityMode
	u.AllowCreateOrganization = setting.Service.DefaultAllowCreateOrganization && !setting.Admin.DisableRegularOrgCreation
	u.EmailNotificationsPreference = setting.Admin.DefaultEmailNotification
	u.MaxRepoCreation = -1
	u.Theme = setting.UI.DefaultTheme
	u.IsRestricted = setting.Service.DefaultUserIsRestricted
	u.IsActive = !(setting.Service.RegisterEmailConfirm || setting.Service.RegisterManualConfirm)

	// Ensure consistency of the dates.
	if u.UpdatedUnix < u.CreatedUnix {
		u.UpdatedUnix = u.CreatedUnix
	}

	// overwrite defaults if set
	if len(overwriteDefault) != 0 && overwriteDefault[0] != nil {
		overwrite := overwriteDefault[0]
		if overwrite.KeepEmailPrivate.Has() {
			u.KeepEmailPrivate = overwrite.KeepEmailPrivate.Value()
		}
		if overwrite.Visibility != nil {
			u.Visibility = *overwrite.Visibility
		}
		if overwrite.AllowCreateOrganization.Has() {
			u.AllowCreateOrganization = overwrite.AllowCreateOrganization.Value()
		}
		if overwrite.EmailNotificationsPreference != nil {
			u.EmailNotificationsPreference = *overwrite.EmailNotificationsPreference
		}
		if overwrite.MaxRepoCreation != nil {
			u.MaxRepoCreation = *overwrite.MaxRepoCreation
		}
		if overwrite.Theme != nil {
			u.Theme = *overwrite.Theme
		}
		if overwrite.IsRestricted.Has() {
			u.IsRestricted = overwrite.IsRestricted.Value()
		}
		if overwrite.IsActive.Has() {
			u.IsActive = overwrite.IsActive.Value()
		}
	}

	// validate data
	if err := ValidateUser(u); err != nil {
		return err
	}

	if createdByAdmin {
		if err := ValidateEmailForAdmin(u.Email); err != nil {
			return err
		}
	} else {
		if err := ValidateEmail(u.Email); err != nil {
			return err
		}
	}

	return db.WithTx(ctx, func(ctx context.Context) error {
		isExist, err := IsUserExist(ctx, 0, u.Name)
		if err != nil {
			return err
		} else if isExist {
			return ErrUserAlreadyExist{u.Name}
		}

		isExist, err = IsEmailUsed(ctx, u.Email)
		if err != nil {
			return err
		} else if isExist {
			return ErrEmailAlreadyUsed{
				Email: u.Email,
			}
		}

		// prepare for database

		u.LowerName = strings.ToLower(u.Name)
		u.AvatarEmail = u.Email
		if u.Rands, err = GetUserSalt(); err != nil {
			return err
		}
		if u.Passwd != "" {
			if err = u.SetPassword(u.Passwd); err != nil {
				return err
			}
		} else {
			u.Salt = ""
			u.PasswdHashAlgo = ""
		}

		// save changes to database

		if err = DeleteUserRedirect(ctx, u.Name); err != nil {
			return err
		}

		if u.CreatedUnix == 0 {
			// Caller expects auto-time for creation & update timestamps.
			err = db.Insert(ctx, u)
		} else {
			// Caller sets the timestamps themselves. They are responsible for ensuring
			// both `CreatedUnix` and `UpdatedUnix` are set appropriately.
			_, err = db.GetEngine(ctx).NoAutoTime().Insert(u)
		}
		if err != nil {
			return err
		}

		if setting.RecordUserSignupMetadata {
			// insert initial IP and UserAgent
			if err = SetUserSetting(ctx, u.ID, SignupIP, meta.InitialIP); err != nil {
				return err
			}

			// trim user agent string to a reasonable length, if necessary
			userAgent := strings.TrimSpace(meta.InitialUserAgent)
			if len(userAgent) > 255 {
				userAgent = userAgent[:255]
			}
			if err = SetUserSetting(ctx, u.ID, SignupUserAgent, userAgent); err != nil {
				return err
			}
		}

		// insert email address
		return db.Insert(ctx, &EmailAddress{
			UID:         u.ID,
			Email:       u.Email,
			LowerEmail:  strings.ToLower(u.Email),
			IsActivated: u.IsActive,
			IsPrimary:   true,
		})
	})
}

// ErrDeleteLastAdminUser represents a "DeleteLastAdminUser" kind of error.
type ErrDeleteLastAdminUser struct {
	UID int64
}

// IsErrDeleteLastAdminUser checks if an error is a ErrDeleteLastAdminUser.
func IsErrDeleteLastAdminUser(err error) bool {
	_, ok := err.(ErrDeleteLastAdminUser)
	return ok
}

func (err ErrDeleteLastAdminUser) Error() string {
	return fmt.Sprintf("can not delete the last admin user [uid: %d]", err.UID)
}

// IsLastAdminUser check whether user is the last admin
func IsLastAdminUser(ctx context.Context, user *User) bool {
	if user.IsAdmin && CountUsers(ctx, &CountUserFilter{IsAdmin: optional.Some(true)}) <= 1 {
		return true
	}
	return false
}

// CountUserFilter represent optional filters for CountUsers
type CountUserFilter struct {
	LastLoginSince *int64
	IsAdmin        optional.Option[bool]
	IsActive       optional.Option[bool]
}

// HasUsers checks whether there are any users in the database, or only one user exists.
func HasUsers(ctx context.Context) (ret struct {
	HasAnyUser, HasOnlyOneUser bool
}, err error,
) {
	res, err := db.GetEngine(ctx).Table(&User{}).Cols("id").Limit(2).Query()
	if err != nil {
		return ret, fmt.Errorf("error checking user existence: %w", err)
	}
	ret.HasAnyUser = len(res) != 0
	ret.HasOnlyOneUser = len(res) == 1
	return ret, nil
}

// CountUsers returns number of users.
func CountUsers(ctx context.Context, opts *CountUserFilter) int64 {
	return countUsers(ctx, opts)
}

func countUsers(ctx context.Context, opts *CountUserFilter) int64 {
	sess := db.GetEngine(ctx)
	cond := builder.NewCond()
	cond = cond.And(builder.Eq{"type": UserTypeIndividual})

	if opts != nil {
		if opts.LastLoginSince != nil {
			cond = cond.And(builder.Gte{"last_login_unix": *opts.LastLoginSince})
		}

		if opts.IsAdmin.Has() {
			cond = cond.And(builder.Eq{"is_admin": opts.IsAdmin.Value()})
		}

		if opts.IsActive.Has() {
			cond = cond.And(builder.Eq{"is_active": opts.IsActive.Value()})
		}
	}

	count, err := sess.Where(cond).Count(new(User))
	if err != nil {
		log.Error("user.countUsers: %v", err)
	}

	return count
}

// GetVerifyUser get user by verify code
func GetVerifyUser(ctx context.Context, code string) (user *User) {
	if len(code) <= base.TimeLimitCodeLength {
		return nil
	}

	// use tail hex username query user
	hexStr := code[base.TimeLimitCodeLength:]
	if b, err := hex.DecodeString(hexStr); err == nil {
		if user, err = GetUserByName(ctx, string(b)); user != nil {
			return user
		}
		log.Error("user.getVerifyUser: %v", err)
	}

	return nil
}

type TimeLimitCodePurpose string

const (
	TimeLimitCodeActivateAccount TimeLimitCodePurpose = "activate_account"
	TimeLimitCodeActivateEmail   TimeLimitCodePurpose = "activate_email"
	TimeLimitCodeResetPassword   TimeLimitCodePurpose = "reset_password"
)

type TimeLimitCodeOptions struct {
	Purpose  TimeLimitCodePurpose
	NewEmail string
}

func makeTimeLimitCodeHashData(opts *TimeLimitCodeOptions, u *User) string {
	return fmt.Sprintf("%s|%d|%s|%s|%s|%s", opts.Purpose, u.ID, strings.ToLower(util.IfZero(opts.NewEmail, u.Email)), u.LowerName, u.Passwd, u.Rands)
}

// GenerateUserTimeLimitCode generates a time-limit code based on user information and given e-mail.
// TODO: need to use cache or db to store it to make sure a code can only be consumed once
func GenerateUserTimeLimitCode(opts *TimeLimitCodeOptions, u *User) string {
	data := makeTimeLimitCodeHashData(opts, u)
	code := base.CreateTimeLimitCode(data, setting.Service.ActiveCodeLives, time.Now(), nil)
	code += hex.EncodeToString([]byte(u.LowerName)) // Add tail hex username
	return code
}

// VerifyUserTimeLimitCode verifies the time-limit code
func VerifyUserTimeLimitCode(ctx context.Context, opts *TimeLimitCodeOptions, code string) (user *User) {
	if user = GetVerifyUser(ctx, code); user != nil {
		// time limit code
		prefix := code[:base.TimeLimitCodeLength]
		data := makeTimeLimitCodeHashData(opts, user)
		if base.VerifyTimeLimitCode(time.Now(), data, setting.Service.ActiveCodeLives, prefix) {
			return user
		}
	}
	return nil
}

// ValidateUser check if user is valid to insert / update into database
func ValidateUser(u *User, cols ...string) error {
	if len(cols) == 0 || util.SliceContainsString(cols, "visibility", true) {
		if !setting.Service.AllowedUserVisibilityModesSlice.IsAllowedVisibility(u.Visibility) && !u.IsOrganization() {
			return fmt.Errorf("visibility Mode not allowed: %s", u.Visibility.String())
		}
	}

	return nil
}

// UpdateUserCols update user according special columns
func UpdateUserCols(ctx context.Context, u *User, cols ...string) error {
	if err := ValidateUser(u, cols...); err != nil {
		return err
	}

	_, err := db.GetEngine(ctx).ID(u.ID).Cols(cols...).Update(u)
	return err
}

// UpdateUserColsNoAutoTime update user according special columns
func UpdateUserColsNoAutoTime(ctx context.Context, u *User, cols ...string) error {
	if err := ValidateUser(u, cols...); err != nil {
		return err
	}

	_, err := db.GetEngine(ctx).ID(u.ID).Cols(cols...).NoAutoTime().Update(u)
	return err
}

// GetInactiveUsers gets all inactive users
func GetInactiveUsers(ctx context.Context, olderThan time.Duration) ([]*User, error) {
	cond := builder.And(
		builder.Eq{"is_active": false},
		builder.Or( // only plain user
			builder.Eq{"`type`": UserTypeIndividual},
			builder.Eq{"`type`": UserTypeUserReserved},
		),
	)

	if olderThan > 0 {
		cond = cond.And(builder.Lt{"created_unix": time.Now().Add(-olderThan).Unix()})
	}

	users := make([]*User, 0, 10)
	return users, db.GetEngine(ctx).
		Where(cond).
		Find(&users)
}

// UserPath returns the path absolute path of user repositories.
func UserPath(userName string) string { //revive:disable-line:exported
	return filepath.Join(setting.RepoRootPath, strings.ToLower(userName))
}

// GetUserByID returns the user object by given ID if exists.
func GetUserByID(ctx context.Context, id int64) (*User, error) {
	u := new(User)
	has, err := db.GetEngine(ctx).ID(id).Get(u)
	if err != nil {
		return nil, err
	} else if !has {
		return nil, ErrUserNotExist{UID: id}
	}
	return u, nil
}

// GetUserByIDs returns the user objects by given IDs if exists.
func GetUserByIDs(ctx context.Context, ids []int64) ([]*User, error) {
	if len(ids) == 0 {
		return nil, nil
	}

	users := make([]*User, 0, len(ids))
	err := db.GetEngine(ctx).In("id", ids).
		Table("user").
		Find(&users)
	return users, err
}

// GetPossibleUserByID returns the user if id > 0 or returns system user if id < 0
func GetPossibleUserByID(ctx context.Context, id int64) (*User, error) {
	if id < 0 {
		if newFunc, ok := globalVars().systemUserNewFuncs[id]; ok {
			return newFunc(), nil
		}
		return nil, ErrUserNotExist{UID: id}
	} else if id == 0 {
		return nil, ErrUserNotExist{}
	}
	return GetUserByID(ctx, id)
}

// GetPossibleUserByIDs returns the users if id > 0 or returns system users if id < 0
func GetPossibleUserByIDs(ctx context.Context, ids []int64) ([]*User, error) {
	uniqueIDs := container.SetOf(ids...)
	users := make([]*User, 0, len(ids))
	_ = uniqueIDs.Remove(0)
	for systemUID, newFunc := range globalVars().systemUserNewFuncs {
		if uniqueIDs.Remove(systemUID) {
			users = append(users, newFunc())
		}
	}
	res, err := GetUserByIDs(ctx, uniqueIDs.Values())
	if err != nil {
		return nil, err
	}
	users = append(users, res...)
	return users, nil
}

// GetUserByName returns user by given name.
func GetUserByName(ctx context.Context, name string) (*User, error) {
	if len(name) == 0 {
		return nil, ErrUserNotExist{Name: name}
	}
	u := &User{LowerName: strings.ToLower(name), Type: UserTypeIndividual}
	has, err := db.GetEngine(ctx).Get(u)
	if err != nil {
		return nil, err
	} else if !has {
		return nil, ErrUserNotExist{Name: name}
	}
	return u, nil
}

// GetUserEmailsByNames returns a list of e-mails corresponds to names of users
// that have their email notifications set to enabled or onmention.
func GetUserEmailsByNames(ctx context.Context, names []string) []string {
	mails := make([]string, 0, len(names))
	for _, name := range names {
		u, err := GetUserByName(ctx, name)
		if err != nil {
			continue
		}
		if u.IsMailable() && u.EmailNotificationsPreference != EmailNotificationsDisabled {
			mails = append(mails, u.Email)
		}
	}
	return mails
}

// GetMailableUsersByIDs gets users from ids, but only if they can receive mails
func GetMailableUsersByIDs(ctx context.Context, ids []int64, isMention bool) ([]*User, error) {
	if len(ids) == 0 {
		return nil, nil
	}
	ous := make([]*User, 0, len(ids))

	if isMention {
		return ous, db.GetEngine(ctx).
			In("id", ids).
			Where("`type` = ?", UserTypeIndividual).
			And("`prohibit_login` = ?", false).
			And("`is_active` = ?", true).
			In("`email_notifications_preference`", EmailNotificationsEnabled, EmailNotificationsOnMention, EmailNotificationsAndYourOwn).
			Find(&ous)
	}

	return ous, db.GetEngine(ctx).
		In("id", ids).
		Where("`type` = ?", UserTypeIndividual).
		And("`prohibit_login` = ?", false).
		And("`is_active` = ?", true).
		In("`email_notifications_preference`", EmailNotificationsEnabled, EmailNotificationsAndYourOwn).
		Find(&ous)
}

// GetUserNameByID returns username for the id
func GetUserNameByID(ctx context.Context, id int64) (string, error) {
	var name string
	has, err := db.GetEngine(ctx).Table("user").Where("id = ?", id).Cols("name").Get(&name)
	if err != nil {
		return "", err
	}
	if has {
		return name, nil
	}
	return "", nil
}

// GetUserIDsByNames returns a slice of ids corresponds to names.
func GetUserIDsByNames(ctx context.Context, names []string, ignoreNonExistent bool) ([]int64, error) {
	ids := make([]int64, 0, len(names))
	for _, name := range names {
		u, err := GetUserByName(ctx, name)
		if err != nil {
			if ignoreNonExistent {
				continue
			}
			return nil, err
		}
		ids = append(ids, u.ID)
	}
	return ids, nil
}

// GetUsersBySource returns a list of Users for a login source
func GetUsersBySource(ctx context.Context, s *auth.Source) ([]*User, error) {
	var users []*User
	err := db.GetEngine(ctx).Where("login_type = ? AND login_source = ?", s.Type, s.ID).Find(&users)
	return users, err
}

// UserCommit represents a commit with validation of user.
type UserCommit struct { //revive:disable-line:exported
	User *User
	*git.Commit
}

// ValidateCommitWithEmail check if author's e-mail of commit is corresponding to a user.
func ValidateCommitWithEmail(ctx context.Context, c *git.Commit) *User {
	if c.Author == nil {
		return nil
	}
	u, err := GetUserByEmail(ctx, c.Author.Email)
	if err != nil {
		return nil
	}
	return u
}

// ValidateCommitsWithEmails checks if authors' e-mails of commits are corresponding to users.
func ValidateCommitsWithEmails(ctx context.Context, oldCommits []*git.Commit) ([]*UserCommit, error) {
	var (
		newCommits = make([]*UserCommit, 0, len(oldCommits))
		emailSet   = make(container.Set[string])
	)
	for _, c := range oldCommits {
		if c.Author != nil {
			emailSet.Add(c.Author.Email)
		}
	}

	emailUserMap, err := GetUsersByEmails(ctx, emailSet.Values())
	if err != nil {
		return nil, err
	}

	for _, c := range oldCommits {
		user := emailUserMap.GetByEmail(c.Author.Email) // FIXME: why ValidateCommitsWithEmails uses "Author", but ParseCommitsWithSignature uses "Committer"?
		newCommits = append(newCommits, &UserCommit{
			User:   user,
			Commit: c,
		})
	}
	return newCommits, nil
}

type EmailUserMap struct {
	m map[string]*User
}

func (eum *EmailUserMap) GetByEmail(email string) *User {
	return eum.m[strings.ToLower(email)]
}

func GetUsersByEmails(ctx context.Context, emails []string) (*EmailUserMap, error) {
	if len(emails) == 0 {
		return nil, nil
	}

	needCheckEmails := make(container.Set[string])
	needCheckUserNames := make(container.Set[string])
	noReplyAddressSuffix := "@" + strings.ToLower(setting.Service.NoReplyAddress)
	for _, email := range emails {
		emailLower := strings.ToLower(email)
		if noReplyUserNameLower, ok := strings.CutSuffix(emailLower, noReplyAddressSuffix); ok {
			needCheckUserNames.Add(noReplyUserNameLower)
			needCheckEmails.Add(emailLower)
		} else {
			needCheckEmails.Add(emailLower)
		}
	}

	emailAddresses := make([]*EmailAddress, 0, len(needCheckEmails))
	if err := db.GetEngine(ctx).In("lower_email", needCheckEmails.Values()).
		And("is_activated=?", true).
		Find(&emailAddresses); err != nil {
		return nil, err
	}
	userIDs := make(container.Set[int64])
	for _, email := range emailAddresses {
		userIDs.Add(email.UID)
	}
	results := make(map[string]*User, len(emails))

	if len(userIDs) > 0 {
		users, err := GetUsersMapByIDs(ctx, userIDs.Values())
		if err != nil {
			return nil, err
		}

		for _, email := range emailAddresses {
			user := users[email.UID]
			if user != nil {
				results[email.LowerEmail] = user
			}
		}
	}

	users := make(map[int64]*User, len(needCheckUserNames))
	if err := db.GetEngine(ctx).In("lower_name", needCheckUserNames.Values()).Find(&users); err != nil {
		return nil, err
	}
	for _, user := range users {
		results[strings.ToLower(user.GetPlaceholderEmail())] = user
	}
	return &EmailUserMap{results}, nil
}

// GetUserByEmail returns the user object by given e-mail if exists.
func GetUserByEmail(ctx context.Context, email string) (*User, error) {
	if len(email) == 0 {
		return nil, ErrUserNotExist{Name: email}
	}

	email = strings.ToLower(email)
	// Otherwise, check in alternative list for activated email addresses
	emailAddress := &EmailAddress{LowerEmail: email, IsActivated: true}
	has, err := db.GetEngine(ctx).Get(emailAddress)
	if err != nil {
		return nil, err
	}
	if has {
		return GetUserByID(ctx, emailAddress.UID)
	}

	// Finally, if email address is the protected email address:
	if strings.HasSuffix(email, "@"+setting.Service.NoReplyAddress) {
		username := strings.TrimSuffix(email, "@"+setting.Service.NoReplyAddress)
		user := &User{}
		has, err := db.GetEngine(ctx).Where("lower_name=?", username).Get(user)
		if err != nil {
			return nil, err
		}
		if has {
			return user, nil
		}
	}

	return nil, ErrUserNotExist{Name: email}
}

// GetUser checks if a user already exists
func GetUser(ctx context.Context, user *User) (bool, error) {
	return db.GetEngine(ctx).Get(user)
}

// GetUserByOpenID returns the user object by given OpenID if exists.
func GetUserByOpenID(ctx context.Context, uri string) (*User, error) {
	if len(uri) == 0 {
		return nil, ErrUserNotExist{Name: uri}
	}

	uri, err := openid.Normalize(uri)
	if err != nil {
		return nil, err
	}

	log.Trace("Normalized OpenID URI: " + uri)

	// Otherwise, check in openid table
	oid := &UserOpenID{}
	has, err := db.GetEngine(ctx).Where("uri=?", uri).Get(oid)
	if err != nil {
		return nil, err
	}
	if has {
		return GetUserByID(ctx, oid.UID)
	}

	return nil, ErrUserNotExist{Name: uri}
}

// GetAdminUser returns the first administrator
func GetAdminUser(ctx context.Context) (*User, error) {
	var admin User
	has, err := db.GetEngine(ctx).
		Where("is_admin=?", true).
		Asc("id"). // Reliably get the admin with the lowest ID.
		Get(&admin)
	if err != nil {
		return nil, err
	} else if !has {
		return nil, ErrUserNotExist{}
	}

	return &admin, nil
}

func isUserVisibleToViewerCond(viewer *User) builder.Cond {
	if viewer != nil && viewer.IsAdmin {
		return builder.NewCond()
	}

	if viewer == nil || viewer.IsRestricted {
		return builder.Eq{
			"`user`.visibility": structs.VisibleTypePublic,
		}
	}

	return builder.Neq{
		"`user`.visibility": structs.VisibleTypePrivate,
	}.Or(
		// viewer self
		builder.Eq{"`user`.id": viewer.ID},
		// viewer's following
		builder.In("`user`.id",
			builder.
				Select("`follow`.user_id").
				From("follow").
				Where(builder.Eq{"`follow`.follow_id": viewer.ID})),
		// viewer's org user
		builder.In("`user`.id",
			builder.
				Select("`team_user`.uid").
				From("team_user").
				Join("INNER", "`team_user` AS t2", "`team_user`.org_id = `t2`.org_id").
				Where(builder.Eq{"`t2`.uid": viewer.ID})),
		// viewer's org
		builder.In("`user`.id",
			builder.
				Select("`team_user`.org_id").
				From("team_user").
				Where(builder.Eq{"`team_user`.uid": viewer.ID})))
}

// IsUserVisibleToViewer check if viewer is able to see user profile
func IsUserVisibleToViewer(ctx context.Context, u, viewer *User) bool {
	if viewer != nil && (viewer.IsAdmin || viewer.ID == u.ID) {
		return true
	}

	switch u.Visibility {
	case structs.VisibleTypePublic:
		return true
	case structs.VisibleTypeLimited:
		if viewer == nil || viewer.IsRestricted {
			return false
		}
		return true
	case structs.VisibleTypePrivate:
		if viewer == nil || viewer.IsRestricted {
			return false
		}

		// If they follow - they see each other
		follower := IsFollowing(ctx, u.ID, viewer.ID)
		if follower {
			return true
		}

		// Now we need to check if they in some organization together
		count, err := db.GetEngine(ctx).Table("team_user").
			Where(
				builder.And(
					builder.Eq{"uid": viewer.ID},
					builder.Or(
						builder.Eq{"org_id": u.ID},
						builder.In("org_id",
							builder.Select("org_id").
								From("team_user", "t2").
								Where(builder.Eq{"uid": u.ID}))))).
			Count()
		if err != nil {
			return false
		}

		if count == 0 {
			// No common organization
			return false
		}

		// they are in an organization together
		return true
	}
	return false
}

// CountWrongUserType count OrgUser who have wrong type
func CountWrongUserType(ctx context.Context) (int64, error) {
	return db.GetEngine(ctx).Where(builder.Eq{"type": 0}.And(builder.Neq{"num_teams": 0})).Count(new(User))
}

// FixWrongUserType fix OrgUser who have wrong type
func FixWrongUserType(ctx context.Context) (int64, error) {
	return db.GetEngine(ctx).Where(builder.Eq{"type": 0}.And(builder.Neq{"num_teams": 0})).Cols("type").NoAutoTime().Update(&User{Type: 1})
}

func GetOrderByName() string {
	if setting.UI.DefaultShowFullName {
		return "full_name, name"
	}
	return "name"
}

// IsFeatureDisabledWithLoginType checks if a user features are disabled, taking into account the login type of the
// user if applicable
func IsFeatureDisabledWithLoginType(user *User, features ...string) bool {
	// NOTE: in the long run it may be better to check the ExternalLoginUser table rather than user.LoginType
	if user != nil && user.LoginType > auth.Plain {
		return setting.Admin.ExternalUserDisableFeatures.Contains(features...)
	}
	return setting.Admin.UserDisabledFeatures.Contains(features...)
}

// DisabledFeaturesWithLoginType returns the set of user features disabled, taking into account the login type
// of the user if applicable
func DisabledFeaturesWithLoginType(user *User) *container.Set[string] {
	// NOTE: in the long run it may be better to check the ExternalLoginUser table rather than user.LoginType
	if user != nil && user.LoginType > auth.Plain {
		return &setting.Admin.ExternalUserDisableFeatures
	}
	return &setting.Admin.UserDisabledFeatures
}

// GetUserOrOrgByName returns the user or org by name
func GetUserOrOrgByName(ctx context.Context, name string) (*User, error) {
	var u User
	has, err := db.GetEngine(ctx).Where("lower_name = ?", strings.ToLower(name)).Get(&u)
	if err != nil {
		return nil, err
	} else if !has {
		return nil, ErrUserNotExist{Name: name}
	}
	return &u, nil
}
