package model

import (
	"time"

	"gorm.io/gorm"
)

// UserStatus 用户状态
type UserStatus string

const (
	UserStatusActive          UserStatus = "active"
	UserStatusBanned          UserStatus = "banned"
	UserStatusInactive        UserStatus = "inactive"
	UserStatusPendingDeletion UserStatus = "pending_deletion"
)

// VisibilityLevel 可见性级别
type VisibilityLevel string

const (
	VisibilityEveryone  VisibilityLevel = "everyone"
	VisibilityFollowing VisibilityLevel = "following"
	VisibilitySelf      VisibilityLevel = "self"
)

// PrivacySettings 隐私设置
type PrivacySettings struct {
	FollowersVisibility VisibilityLevel `json:"followers_visibility" gorm:"type:varchar(20);default:everyone"`
	FollowingVisibility VisibilityLevel `json:"following_visibility" gorm:"type:varchar(20);default:everyone"`
	PostsVisibility     VisibilityLevel `json:"posts_visibility" gorm:"type:varchar(20);default:everyone"`
	FavoritesVisibility VisibilityLevel `json:"favorites_visibility" gorm:"type:varchar(20);default:everyone"`
}

// UserIdentity 用户身份类型
type UserIdentity string

const (
	UserIdentityGeneral  UserIdentity = "general"  // 普通用户
	UserIdentityStudent  UserIdentity = "student"  // 学生
	UserIdentityTeacher  UserIdentity = "teacher"  // 教师
	UserIdentityStaff    UserIdentity = "staff"    // 职工
	UserIdentityAlumni   UserIdentity = "alumni"   // 校友
	UserIdentityExternal UserIdentity = "external" // 外部人员
)

// VerificationStatus 审核状态
type VerificationStatus string

const (
	VerificationStatusNotSubmitted VerificationStatus = "not_submitted" // 未提交
	VerificationStatusPending      VerificationStatus = "pending"       // 审核中
	VerificationStatusApproved     VerificationStatus = "approved"      // 已通过
	VerificationStatusRejected     VerificationStatus = "rejected"      // 已拒绝
	VerificationStatusNone         VerificationStatus = "none"          // 无认证（对外展示用）
)

// User 用户实体
type User struct {
	ID            string  `json:"id" gorm:"type:varchar(36);primaryKey"`
	Username      string  `json:"username" gorm:"type:varchar(50);uniqueIndex;not null"`
	Nickname      string  `json:"nickname" gorm:"type:varchar(100);not null"`
	Email         *string `json:"email" gorm:"type:varchar(255);uniqueIndex"`
	Phone         *string `json:"phone" gorm:"type:varchar(20);uniqueIndex"`
	EmailVerified bool    `json:"email_verified" gorm:"default:false"`
	PasswordHash  string  `json:"-" gorm:"type:varchar(255);not null"`
	Avatar        string  `json:"avatar" gorm:"type:text"`
	CoverURL      string  `json:"cover_url" gorm:"type:text"` // 头图URL
	Bio           string  `json:"bio" gorm:"type:text"`
	Website       string  `json:"website" gorm:"type:varchar(255)"`
	Location      string  `json:"location" gorm:"type:varchar(100)"`

	// 实名认证信息（可选）
	RealName   string     `json:"real_name" gorm:"type:varchar(100)"` // 真实姓名
	IDCard     string     `json:"-" gorm:"type:varchar(18)"`          // 身份证号（加密存储）
	IsVerified bool       `json:"is_verified" gorm:"default:false"`   // 是否实名认证
	VerifiedAt *time.Time `json:"verified_at" gorm:"type:timestamp"`

	// 统计计数
	PostsCount     int `json:"posts_count" gorm:"default:0"`
	FollowersCount int `json:"followers_count" gorm:"default:0"`
	FollowingCount int `json:"following_count" gorm:"default:0"`

	// 身份认证
	Identity           UserIdentity       `json:"identity" gorm:"type:varchar(20);default:general"`
	VerificationStatus VerificationStatus `json:"verification_status" gorm:"type:varchar(20);default:not_submitted"`

	// 状态
	Status      UserStatus `json:"status" gorm:"type:varchar(20);default:active"`
	LastLoginAt *time.Time `json:"last_login_at" gorm:"type:timestamp"`
	LastLoginIP string     `json:"last_login_ip" gorm:"type:varchar(45)"`

	// 账号注销
	DeletionRequestedAt *time.Time `json:"deletion_requested_at" gorm:"type:timestamp"`

	// 隐私设置
	PrivacySettings PrivacySettings `json:"privacy_settings" gorm:"embedded;embeddedPrefix:privacy_"`

	// 时间戳
	CreatedAt time.Time      `json:"created_at" gorm:"autoCreateTime"`
	UpdatedAt time.Time      `json:"updated_at" gorm:"autoUpdateTime"`
	DeletedAt gorm.DeletedAt `json:"-" gorm:"index"`
}

// BeforeCreate 创建前生成UUID
func (u *User) BeforeCreate(tx *gorm.DB) error {
	SetUUIDIfEmpty(&u.ID)
	return nil
}

func (User) TableName() string {
	return "users"
}