package model

import (
	"time"

	"gorm.io/gorm"

	"carrot_bbs/internal/pkg/utils"
)

// PushChannel 推送通道类型
type PushChannel string

const (
	PushChannelWebSocket PushChannel = "websocket" // WebSocket推送
	PushChannelFCM       PushChannel = "fcm"       // Firebase Cloud Messaging
	PushChannelAPNs      PushChannel = "apns"      // Apple Push Notification service
	PushChannelHuawei    PushChannel = "huawei"    // 华为推送
)

// PushStatus 推送状态
type PushStatus string

const (
	PushStatusPending   PushStatus = "pending"   // 待推送
	PushStatusPushing   PushStatus = "pushing"   // 推送中
	PushStatusPushed    PushStatus = "pushed"    // 已推送（成功发送到推送服务）
	PushStatusDelivered PushStatus = "delivered" // 已送达（客户端确认）
	PushStatusFailed    PushStatus = "failed"    // 推送失败
	PushStatusExpired   PushStatus = "expired"   // 消息过期
)

// PushRecord 推送记录实体
// 用于跟踪消息的推送状态，支持多设备推送和重试机制
type PushRecord struct {
	ID          int64       `gorm:"primaryKey;autoIncrement:false" json:"id"`                       // 雪花算法ID
	UserID      string      `gorm:"column:user_id;type:varchar(50);index;not null" json:"user_id"`  // 目标用户ID (UUID格式)
	MessageID   string      `gorm:"index;not null;size:20" json:"message_id"`                       // 关联的消息ID (string类型)
	PushChannel PushChannel `gorm:"type:varchar(20);not null" json:"push_channel"`                  // 推送通道
	PushStatus  PushStatus  `gorm:"type:varchar(20);not null;default:'pending'" json:"push_status"` // 推送状态

	// 设备信息
	DeviceToken string `gorm:"type:varchar(256)" json:"device_token,omitempty"` // 设备Token（用于手机推送）
	DeviceType  string `gorm:"type:varchar(20)" json:"device_type,omitempty"`   // 设备类型 (ios/android/web)

	// 重试机制
	RetryCount int `gorm:"default:0" json:"retry_count"` // 重试次数
	MaxRetry   int `gorm:"default:3" json:"max_retry"`   // 最大重试次数

	// 时间戳
	PushedAt    *time.Time `json:"pushed_at,omitempty"`               // 推送时间
	DeliveredAt *time.Time `json:"delivered_at,omitempty"`            // 送达时间
	ExpiredAt   *time.Time `gorm:"index" json:"expired_at,omitempty"` // 过期时间

	// 错误信息
	ErrorMessage string `gorm:"type:varchar(500)" json:"error_message,omitempty"` // 错误信息

	// 软删除
	DeletedAt gorm.DeletedAt `json:"-" gorm:"index"`

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

// BeforeCreate 创建前生成雪花算法ID
func (r *PushRecord) BeforeCreate(tx *gorm.DB) error {
	if r.ID == 0 {
		id, err := utils.GetSnowflake().GenerateID()
		if err != nil {
			return err
		}
		r.ID = id
	}
	return nil
}

func (PushRecord) TableName() string {
	return "push_records"
}

// CanRetry 判断是否可以重试
func (r *PushRecord) CanRetry() bool {
	return r.RetryCount < r.MaxRetry && r.PushStatus != PushStatusDelivered && r.PushStatus != PushStatusExpired
}

// IsExpired 判断是否已过期
func (r *PushRecord) IsExpired() bool {
	if r.ExpiredAt == nil {
		return false
	}
	return time.Now().After(*r.ExpiredAt)
}

// MarkPushing 标记为推送中
func (r *PushRecord) MarkPushing() {
	r.PushStatus = PushStatusPushing
}

// MarkPushed 标记为已推送
func (r *PushRecord) MarkPushed() {
	now := time.Now()
	r.PushStatus = PushStatusPushed
	r.PushedAt = &now
}

// MarkDelivered 标记为已送达
func (r *PushRecord) MarkDelivered() {
	now := time.Now()
	r.PushStatus = PushStatusDelivered
	r.DeliveredAt = &now
}

// MarkFailed 标记为推送失败
func (r *PushRecord) MarkFailed(errMsg string) {
	r.PushStatus = PushStatusFailed
	r.ErrorMessage = errMsg
	r.RetryCount++
}

// MarkExpired 标记为已过期
func (r *PushRecord) MarkExpired() {
	r.PushStatus = PushStatusExpired
}

// IncrementRetry 增加重试次数
func (r *PushRecord) IncrementRetry() {
	r.RetryCount++
}