// Package prioritypolling 提供卡轮询优先项的只读查询投影。
//
// 读取不经聚合根、不修改任何状态；数据范围按事实表冗余的卡店铺快照下推，
// 平台卡（快照为空）与范围外的行对代理账号同等不可见，越权与不存在不得形成可枚举差异。
package prioritypolling

import (
	"context"
	stderrors "errors"
	"strings"

	"gorm.io/gorm"

	"github.com/break/junhong_cmp_fiber/internal/model"
	"github.com/break/junhong_cmp_fiber/internal/model/dto"
	pollingsvc "github.com/break/junhong_cmp_fiber/internal/service/polling"
	"github.com/break/junhong_cmp_fiber/internal/store/postgres"
	"github.com/break/junhong_cmp_fiber/pkg/constants"
	"github.com/break/junhong_cmp_fiber/pkg/errors"
)

// Query 优先轮询项只读查询。
type Query struct {
	db    *gorm.DB
	store *postgres.PollingPriorityItemStore
}

// NewQuery 创建优先轮询项查询。
func NewQuery(db *gorm.DB, store *postgres.PollingPriorityItemStore) *Query {
	return &Query{db: db, store: store}
}

// List 分页查询优先轮询项，按创建时间倒序，并按当前账号数据范围下推。
func (q *Query) List(ctx context.Context, req dto.PriorityPollingItemListRequest) (*dto.PriorityPollingItemListResponse, error) {
	if q == nil || q.store == nil {
		return nil, errors.New(errors.CodeInternalError, "优先轮询项查询未配置")
	}
	scope, err := priorityPollingShopScope(ctx)
	if err != nil {
		return nil, err
	}
	filter := postgres.PollingPriorityItemListFilter{
		CardID:         req.CardID,
		TaskType:       req.TaskType,
		Status:         req.Status,
		TriggerType:    req.TriggerType,
		ShopIDSnapshot: scope,
		Page:           req.Page,
		PageSize:       req.PageSize,
	}
	items, total, err := q.store.List(ctx, filter)
	if err != nil {
		return nil, err
	}
	list, err := q.projectList(ctx, items)
	if err != nil {
		return nil, err
	}
	page, pageSize := normalizePage(req.Page, req.PageSize)
	return &dto.PriorityPollingItemListResponse{
		List: list, Total: total, Page: page, PageSize: pageSize,
	}, nil
}

// Detail 查询优先轮询项详情，并按当前账号数据范围下推。
// 越权与不存在返回同一稳定错误，不提供可枚举差异。
func (q *Query) Detail(ctx context.Context, id uint) (*dto.PriorityPollingItemResponse, error) {
	if q == nil || q.store == nil {
		return nil, errors.New(errors.CodeInternalError, "优先轮询项查询未配置")
	}
	scope, err := priorityPollingShopScope(ctx)
	if err != nil {
		return nil, err
	}
	item, err := q.store.GetByIDScoped(ctx, id, scope)
	if err != nil {
		if stderrors.Is(err, gorm.ErrRecordNotFound) {
			// 越权与不存在共用同一稳定错误，避免通过状态码枚举他人资源。
			return nil, errors.New(errors.CodeForbidden, priorityPollingDeniedMessage)
		}
		return nil, errors.Wrap(errors.CodeDatabaseError, err, "查询优先轮询项详情失败")
	}
	iccid := q.loadICCID(ctx, []*model.PollingPriorityItem{item})
	return toPriorityPollingItemResponse(item, iccid[item.CardID]), nil
}

// projectList 批量载入卡的 ICCID 后投影列表，避免逐行查询。
func (q *Query) projectList(ctx context.Context, items []*model.PollingPriorityItem) ([]*dto.PriorityPollingItemResponse, error) {
	if len(items) == 0 {
		return []*dto.PriorityPollingItemResponse{}, nil
	}
	iccids := q.loadICCID(ctx, items)
	list := make([]*dto.PriorityPollingItemResponse, 0, len(items))
	for _, item := range items {
		if item == nil {
			continue
		}
		list = append(list, toPriorityPollingItemResponse(item, iccids[item.CardID]))
	}
	return list, nil
}

// loadICCID 按本批卡ID一次投影 ICCID，已删除的卡不返回，由响应保留空字符串。
func (q *Query) loadICCID(ctx context.Context, items []*model.PollingPriorityItem) map[uint]string {
	cardIDs := make([]uint, 0, len(items))
	seen := make(map[uint]bool, len(items))
	for _, item := range items {
		if item == nil || seen[item.CardID] {
			continue
		}
		seen[item.CardID] = true
		cardIDs = append(cardIDs, item.CardID)
	}
	result := make(map[uint]string, len(cardIDs))
	if len(cardIDs) == 0 {
		return result
	}
	type cardICCIDRow struct {
		ID    uint   `gorm:"column:id"`
		ICCID string `gorm:"column:iccid"`
	}
	var rows []cardICCIDRow
	if err := q.db.WithContext(ctx).
		Model(&model.IotCard{}).
		Select("id, iccid").
		Where("id IN ? AND deleted_at IS NULL", cardIDs).
		Scan(&rows).Error; err != nil {
		// 卡号只用于展示，查询失败降级为空号，不影响读取优先轮询事实。
		return result
	}
	for _, row := range rows {
		result[row.ID] = row.ICCID
	}
	return result
}

// priorityPollingShopScope 返回当前账号可访问的店铺快照范围，并完成读侧鉴权。
//
// 复用与人工入队同一套用户类型分类（internal/service/polling.PriorityPollingReadScope）：
// 只有超级管理员与平台账号不受限（nil）；企业账号与未预计算范围的账号一律拒绝。
// 返回 nil 表示不受限，非 nil 时按列表下推，空切片表示空结果。
func priorityPollingShopScope(ctx context.Context) ([]uint, error) {
	return pollingsvc.PriorityPollingReadScope(ctx)
}

// priorityPollingDeniedMessage 与人工入队共用同一拒绝文案。
const priorityPollingDeniedMessage = "无权限操作该资源或资源不存在"

// normalizePage 归一化分页参数并执行默认值与上限。
func normalizePage(page, pageSize int) (int, int) {
	if page < 1 {
		page = constants.DefaultPage
	}
	if pageSize < 1 || pageSize > constants.MaxPageSize {
		pageSize = constants.DefaultPageSize
	}
	return page, pageSize
}

// toPriorityPollingItemResponse 把事实行投影为读侧 DTO，枚举按 constants 提供中文名称。
func toPriorityPollingItemResponse(item *model.PollingPriorityItem, iccid string) *dto.PriorityPollingItemResponse {
	if item == nil {
		return nil
	}
	return &dto.PriorityPollingItemResponse{
		ID:               item.ID,
		CardID:           item.CardID,
		ICCID:            iccid,
		TaskType:         item.TaskType,
		TaskTypeName:     constants.PollingPriorityTaskTypeName(item.TaskType),
		Status:           item.Status,
		StatusName:       constants.PollingPriorityStatusName(item.Status),
		TriggerType:      item.TriggerType,
		TriggerTypeName:  constants.PollingPriorityTriggerName(item.TriggerType),
		TriggerTypes:     strings.Trim(item.TriggerTypes, ","),
		TriggerCount:     item.TriggerCount,
		LastTriggeredAt:  item.LastTriggeredAt,
		SourceOrderID:    item.SourceOrderID,
		SourcePackageUse: item.SourcePackageUsageID,
		AttemptCount:     item.AttemptCount,
		ClaimedAt:        item.ClaimedAt,
		ManualReason:     item.ManualReason,
		ManualOperator:   item.ManualOperatorID,
		ManualOperatorNm: item.ManualOperatorName,
		ShopIDSnapshot:   item.ShopIDSnapshot,
		Result:           item.Result,
		ResultName:       constants.PollingPriorityResultName(item.Result),
		FailureReason:    item.FailureReason,
		CreatedAt:        item.CreatedAt,
		UpdatedAt:        item.UpdatedAt,
	}
}