app-cloudep-tweeting-service/internal/logic/postservice/list_posts_logic.go

package postservicelogic

import (
	"app-cloudep-tweeting-service/internal/domain"
	model "app-cloudep-tweeting-service/internal/model/mongo"
	"context"

	ers "code.30cm.net/digimon/library-go/errs"
	"google.golang.org/protobuf/proto"

	"app-cloudep-tweeting-service/gen_result/pb/tweeting"
	"app-cloudep-tweeting-service/internal/svc"

	"github.com/zeromicro/go-zero/core/logx"
)

type ListPostsLogic struct {
	ctx    context.Context
	svcCtx *svc.ServiceContext
	logx.Logger
}

func NewListPostsLogic(ctx context.Context, svcCtx *svc.ServiceContext) *ListPostsLogic {
	return &ListPostsLogic{
		ctx:    ctx,
		svcCtx: svcCtx,
		Logger: logx.WithContext(ctx),
	}
}

// 只列出要驗證的資料
type listReq struct {
	OnlyAdds  int32 `json:"only_adds" validate:"oneof=0 1 2 3"`
	PageSize  int64 `json:"page_size" validate:"required"`
	PageIndex int64 `json:"page_index" validate:"required"`
}

// 將單個 Post 轉換為 PostDetailItem
func convertToPostDetailItem(item *model.Post) *tweeting.PostDetailItem {
	media := make([]*tweeting.Media, 0, len(item.MediaURL))
	for _, subItem := range item.MediaURL {
		media = append(media, &tweeting.Media{
			Type: subItem.Type,
			Url:  subItem.Links,
		})
	}

	return &tweeting.PostDetailItem{
		PostId:       item.ID.Hex(),
		Uid:          item.UID,
		Content:      item.Content,
		Tags:         item.Tags,
		Media:        media,
		IsAd:         item.IsAd,
		CreatedAt:    item.CreateAt,
		UpdateAt:     item.UpdateAt,
		LikeCount:    item.Like,
		DislikeCount: item.DisLike,
	}
}

// ListPosts 查詢貼文 -> 主流程
func (l *ListPostsLogic) ListPosts(in *tweeting.QueryPostsReq) (*tweeting.ListPostsResp, error) {
	// 將 PageSize 和 PageIndex 提前轉換為 int64
	pageSize := int64(in.GetPageSize())
	pageIndex := int64(in.GetPageIndex())

	// 驗證資料
	if err := l.svcCtx.Validate.ValidateAll(&listReq{
		PageSize:  pageSize,
		PageIndex: pageIndex,
		OnlyAdds:  in.GetOnlyAds(),
	}); err != nil {
		// 錯誤代碼 05-011-00
		return nil, ers.InvalidFormat(err.Error())
	}

	// 構建查詢條件
	query := &model.QueryPostModelReq{
		UID:       in.GetUid(),
		Id:        in.GetPostId(),
		PageSize:  pageSize,
		PageIndex: pageIndex,
	}

	// 處理 OnlyAds 條件
	if in.OnlyAds != nil {
		onlyAds := in.GetOnlyAds()
		query.OnlyAds = proto.Bool(onlyAds == domain.AdTypeOnlyAd.ToInt32())
	}

	// 執行查詢
	find, count, err := l.svcCtx.PostModel.Find(l.ctx, query)
	if err != nil {
		// 錯誤代碼 05-021-05
		e := domain.CommentErrorL(
			domain.ListPostError,
			logx.WithContext(l.ctx),
			[]logx.LogField{
				{Key: "query", Value: query},
				{Key: "func", Value: "PostModel.Find"},
				{Key: "err", Value: err},
			},
			"failed to find posts").Wrap(err)

		return nil, e
	}

	// 將查詢結果轉換為 API 回應格式
	result := make([]*tweeting.PostDetailItem, 0, count)
	for _, item := range find {
		result = append(result, convertToPostDetailItem(item))
	}

	// 返回結果
	return &tweeting.ListPostsResp{
		Posts: result,
		Page: &tweeting.Pager{
			Total: count,
			Index: pageIndex,
			Size:  pageSize,
		},
	}, nil
}