package exporter

import (
	"context"
	"strconv"

	"gorm.io/gorm"

	"github.com/break/junhong_cmp_fiber/internal/model"
	"github.com/break/junhong_cmp_fiber/pkg/constants"
)

// DeviceSceneStrategy 设备导出场景策略。
type DeviceSceneStrategy struct {
	db *gorm.DB
}

// NewDeviceSceneStrategy 创建设备场景策略。
func NewDeviceSceneStrategy(db *gorm.DB) *DeviceSceneStrategy {
	return &DeviceSceneStrategy{db: db}
}

// Scene 场景编码。
func (s *DeviceSceneStrategy) Scene() string {
	return constants.ExportTaskSceneDevice
}

// Headers 导出表头。
func (s *DeviceSceneStrategy) Headers() []string {
	return []string{"ID", "设备虚拟号", "设备名称", "设备型号", "设备类型", "状态", "店铺ID", "创建时间"}
}

// NextShardBoundary 获取下一段分片边界。
func (s *DeviceSceneStrategy) NextShardBoundary(ctx context.Context, task *model.ExportTask, afterID uint64, limit int) (*ShardBoundary, error) {
	if limit <= 0 {
		limit = constants.ExportDefaultShardSize
	}

	var ids []uint64
	query := s.db.WithContext(ctx).
		Model(&model.Device{}).
		Where("id > ?", afterID).
		Order("id ASC").
		Limit(limit)
	query = applyShopScopeForTask(query, task)

	if err := query.Pluck("id", &ids).Error; err != nil {
		return nil, err
	}
	if len(ids) == 0 {
		return nil, nil
	}

	return &ShardBoundary{
		StartID:  afterID,
		EndID:    ids[len(ids)-1],
		RowCount: len(ids),
	}, nil
}

// QueryRows 查询分片内数据行。
func (s *DeviceSceneStrategy) QueryRows(ctx context.Context, task *model.ExportTask, startID, endID uint64) ([][]string, error) {
	if endID == 0 {
		return [][]string{}, nil
	}

	var devices []model.Device
	query := s.db.WithContext(ctx).
		Model(&model.Device{}).
		Where("id > ? AND id <= ?", startID, endID).
		Order("id ASC")
	query = applyShopScopeForTask(query, task)

	if err := query.Find(&devices).Error; err != nil {
		return nil, err
	}

	rows := make([][]string, 0, len(devices))
	for _, item := range devices {
		shopID := ""
		if item.ShopID != nil {
			shopID = strconv.FormatUint(uint64(*item.ShopID), 10)
		}

		rows = append(rows, []string{
			strconv.FormatUint(uint64(item.ID), 10),
			item.VirtualNo,
			item.DeviceName,
			item.DeviceModel,
			item.DeviceType,
			strconv.Itoa(item.Status),
			shopID,
			item.CreatedAt.Format("2006-01-02 15:04:05"),
		})
	}

	return rows, nil
}