package mysqldao

import (
	"context"

	"git.lzcwy.cn/zhengchiliu/zt-closet-backend/global"
	"git.lzcwy.cn/zhengchiliu/zt-closet-backend/internal/mysqlmodel"
	"gorm.io/gorm"
)

// NotificationDao 用户通知数据访问
type NotificationDao struct {
	db *gorm.DB
}

// NewNotificationDao 创建通知 DAO
func NewNotificationDao() *NotificationDao {
	return &NotificationDao{db: global.MysqlEngine}
}

// NotificationCreate 创建通知
func (d *NotificationDao) NotificationCreate(ctx context.Context, notification *mysqlmodel.UserNotification) error {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.NotificationCreate")
	defer span.End()

	if err := d.db.WithContext(ctx).Create(notification).Error; err != nil {
		span.RecordError(err)
		return err
	}
	return nil
}

// NotificationUpdateReadByUUID 标记通知已读
func (d *NotificationDao) NotificationUpdateReadByUUID(ctx context.Context, notificationUUID string) error {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.NotificationUpdateReadByUUID")
	defer span.End()

	if err := d.db.WithContext(ctx).Model(&mysqlmodel.UserNotification{}).
		Where("notification_uuid = ?", notificationUUID).
		Update("is_read", int8(2)).Error; err != nil {
		span.RecordError(err)
		return err
	}
	return nil
}

// NotificationUpdateReadByUUIDIfUnread 条件标记已读（仅未读 -> 已读），返回是否更新成功，
// 用于防并发重复扣减未读数。
func (d *NotificationDao) NotificationUpdateReadByUUIDIfUnread(ctx context.Context, notificationUUID string) (bool, error) {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.NotificationUpdateReadByUUIDIfUnread")
	defer span.End()

	res := d.db.WithContext(ctx).Model(&mysqlmodel.UserNotification{}).
		Where("notification_uuid = ? AND is_read = ?", notificationUUID, int8(1)).
		Update("is_read", int8(2))
	if res.Error != nil {
		span.RecordError(res.Error)
		return false, res.Error
	}
	return res.RowsAffected > 0, nil
}

// NotificationUpdateReadAllByUserID 将该用户全部未读通知标记为已读，返回影响行数。
// 条件带 is_read = 1，保证只统计本次真正从未读变为已读的条数（幂等，重复调用返回 0）。
func (d *NotificationDao) NotificationUpdateReadAllByUserID(ctx context.Context, userID int64) (int64, error) {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.NotificationUpdateReadAllByUserID")
	defer span.End()

	res := d.db.WithContext(ctx).Model(&mysqlmodel.UserNotification{}).
		Where("user_id = ? AND is_read = ?", userID, int8(1)).
		Update("is_read", int8(2))
	if res.Error != nil {
		span.RecordError(res.Error)
		return 0, res.Error
	}
	return res.RowsAffected, nil
}

// NotificationGetByUUID 按 UUID 查询通知
func (d *NotificationDao) NotificationGetByUUID(ctx context.Context, notificationUUID string) (*mysqlmodel.UserNotification, error) {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.NotificationGetByUUID")
	defer span.End()

	var notification mysqlmodel.UserNotification
	if err := d.db.WithContext(ctx).Where("notification_uuid = ?", notificationUUID).First(&notification).Error; err != nil {
		span.RecordError(err)
		return nil, err
	}
	return &notification, nil
}

// NotificationCountUnread 统计用户未读数
func (d *NotificationDao) NotificationCountUnread(ctx context.Context, userID int64) (int64, error) {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.NotificationCountUnread")
	defer span.End()

	var count int64
	if err := d.db.WithContext(ctx).Model(&mysqlmodel.UserNotification{}).
		Where("user_id = ? AND is_read = ?", userID, int8(1)).
		Count(&count).Error; err != nil {
		span.RecordError(err)
		return 0, err
	}
	return count, nil
}

// NotificationListByUserID 分页查询用户通知（isRead/msgType 为 0 不筛选）
func (d *NotificationDao) NotificationListByUserID(ctx context.Context, userID int64, isRead, msgType int8, page, pageSize int) ([]mysqlmodel.UserNotification, int64, error) {
	ctx, span := global.Tracer.Start(ctx, "mysqldao.NotificationListByUserID")
	defer span.End()

	var list []mysqlmodel.UserNotification
	var total int64
	q := d.db.WithContext(ctx).Model(&mysqlmodel.UserNotification{}).Where("user_id = ?", userID)
	if isRead != 0 {
		q = q.Where("is_read = ?", isRead)
	}
	if msgType != 0 {
		q = q.Where("msg_type = ?", msgType)
	}
	if err := q.Count(&total).Error; err != nil {
		span.RecordError(err)
		return nil, 0, err
	}
	if err := q.Offset((page - 1) * pageSize).Limit(pageSize).Order("id DESC").Find(&list).Error; err != nil {
		span.RecordError(err)
		return nil, 0, err
	}
	return list, total, nil
}