neo-blog/internal/service/post.go

package service

import (
  "context"
  "strconv"

  "github.com/snowykami/neo-blog/internal/ctxutils"
  "github.com/snowykami/neo-blog/internal/dto"
  "github.com/snowykami/neo-blog/internal/model"
  "github.com/snowykami/neo-blog/internal/repo"
  "github.com/snowykami/neo-blog/pkg/errs"
)

type PostService struct{}

func NewPostService() *PostService {
  return &PostService{}
}

func (p *PostService) CreatePost(ctx context.Context, req *dto.CreateOrUpdatePostReq) (uint, error) {
  currentUser, ok := ctxutils.GetCurrentUser(ctx)
  if !ok {
    return 0, errs.ErrUnauthorized
  }
  post := &model.Post{
    Title:   req.Title,
    Content: req.Content,
    UserID:  currentUser.ID,
    Labels: func() []model.Label {
      labelModels := make([]model.Label, 0)
      for _, labelID := range req.Labels {
        labelModel, err := repo.Label.GetLabelByID(strconv.Itoa(int(labelID)))
        if err == nil {
          labelModels = append(labelModels, *labelModel)
        }
      }
      return labelModels
    }(),
    IsPrivate: req.IsPrivate,
  }
  if err := repo.Post.CreatePost(post); err != nil {
    return 0, err
  }
  return post.ID, nil
}

func (p *PostService) DeletePost(ctx context.Context, id string) error {
  currentUser, ok := ctxutils.GetCurrentUser(ctx)
  if !ok {
    return errs.ErrUnauthorized
  }
  if id == "" {
    return errs.ErrBadRequest
  }
  post, err := repo.Post.GetPostByID(id)
  if err != nil {
    return errs.New(errs.ErrNotFound.Code, "post not found", err)
  }
  if post.UserID != currentUser.ID {
    return errs.ErrForbidden
  }
  if err := repo.Post.DeletePost(id); err != nil {
    return errs.ErrInternalServer
  }
  return nil
}

func (p *PostService) GetPost(ctx context.Context, id string) (*dto.PostDto, error) {
  if id == "" {
    return nil, errs.ErrBadRequest
  }
  post, err := repo.Post.GetPostByID(id)
  if err != nil {
    return nil, errs.New(errs.ErrNotFound.Code, "post not found", err)
  }
  currentUser, ok := ctxutils.GetCurrentUser(ctx)
  if post.IsPrivate && (!ok || post.UserID != currentUser.ID) {
    return nil, errs.ErrForbidden
  }

  return post.ToDto(), nil
}

func (p *PostService) UpdatePost(ctx context.Context, id string, req *dto.CreateOrUpdatePostReq) (uint, error) {
  currentUser, ok := ctxutils.GetCurrentUser(ctx)
  if !ok {
    return 0, errs.ErrUnauthorized
  }
  if id == "" {
    return 0, errs.ErrBadRequest
  }
  post, err := repo.Post.GetPostByID(id)
  if err != nil {
    return 0, errs.New(errs.ErrNotFound.Code, "post not found", err)
  }
  if post.UserID != currentUser.ID {
    return 0, errs.ErrForbidden
  }
  post.Title = req.Title
  post.Content = req.Content
  post.IsPrivate = req.IsPrivate
  post.Labels = func() []model.Label {
    labelModels := make([]model.Label, len(req.Labels))
    for _, labelID := range req.Labels {
      labelModel, err := repo.Label.GetLabelByID(strconv.Itoa(int(labelID)))
      if err == nil {
        labelModels = append(labelModels, *labelModel)
      }
    }
    return labelModels
  }()
  if err := repo.Post.UpdatePost(post); err != nil {
    return 0, errs.ErrInternalServer
  }
  return post.ID, nil
}

func (p *PostService) ListPosts(ctx context.Context, req *dto.ListPostReq) ([]*dto.PostDto, int64, error) {
  postDtos := make([]*dto.PostDto, 0)
  currentUserID, _ := ctxutils.GetCurrentUserID(ctx)
  posts, total, err := repo.Post.ListPosts(currentUserID, req.Keywords, req.Labels, req.LabelRule, req.Page, req.Size, req.OrderBy, req.Desc)
  if err != nil {
    return nil, total, errs.New(errs.ErrInternalServer.Code, "failed to list posts", err)
  }
  for _, post := range posts {
    postDtos = append(postDtos, post.ToDtoWithShortContent(100))
  }
  return postDtos, total, nil
}

func (p *PostService) ToggleLikePost(ctx context.Context, id string) (bool, error) {
  currentUser, ok := ctxutils.GetCurrentUser(ctx)
  if !ok {
    return false, errs.ErrUnauthorized
  }
  if id == "" {
    return false, errs.ErrBadRequest
  }
  post, err := repo.Post.GetPostByID(id)
  if err != nil {
    return false, errs.New(errs.ErrNotFound.Code, "post not found", err)
  }
  if post.UserID == currentUser.ID {
    return false, errs.ErrForbidden
  }
  idInt, err := strconv.ParseUint(id, 10, 64)
  if err != nil {
    return false, errs.New(errs.ErrBadRequest.Code, "invalid post ID", err)
  }
  liked, err := repo.Post.ToggleLikePost(uint(idInt), currentUser.ID)
  if err != nil {
    return false, errs.ErrInternalServer
  }
  return liked, nil
}