691 lines
23 KiB
Go
691 lines
23 KiB
Go
// Package service — social bits of the BFF.
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//
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// `social_service.go` bundles three lightweight services (Post, Bookmark,
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// Collection) because each is small (10–40 LOC of logic) and they share the
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// same R2 + UserRepo dependencies. Keeping them together keeps `server.go`'s
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// init-wiring tidy without sprawling into 4 separate files.
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package service
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import (
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"context"
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"crypto/rand"
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"encoding/hex"
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"errors"
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"fmt"
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"path"
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"strings"
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"time"
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"github.com/prabhupadasays/spsays-bff/internal/model"
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"github.com/prabhupadasays/spsays-bff/internal/repository"
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)
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// Sentinels surfaced to handlers.
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var (
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ErrForbidden = errors.New("forbidden")
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ErrNotFound = errors.New("not found")
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)
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// ---------------------------------------------------------------------------
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// PostService
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// ---------------------------------------------------------------------------
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type PostService struct {
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posts *repository.PostRepo
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r2 *repository.R2
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likes *repository.LikeRepo
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mentions *repository.MentionRepo
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comments *repository.CommentRepo
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notif *NotificationService // optional; set via SetNotifier
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}
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func NewPostService(posts *repository.PostRepo, r2 *repository.R2, likes *repository.LikeRepo, mentions *repository.MentionRepo, comments *repository.CommentRepo) *PostService {
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return &PostService{posts: posts, r2: r2, likes: likes, mentions: mentions, comments: comments}
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}
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// SetNotifier wires the notification seam after construction (the
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// NotificationService is built later in server wiring than PostService).
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func (s *PostService) SetNotifier(n *NotificationService) { s.notif = n }
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// Create persists a new post. The caption is treated as opaque — we trust
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// the frontend to send the exact text the user selected. Source URL must be
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// a same-origin path (e.g. /books/bg/1/1?hl=…) — we strip the host if one
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// was provided so links can't be hijacked.
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func (s *PostService) Create(ctx context.Context, userID, caption, sourceURL, sourceTitle string, imageURLs, mentionUserIDs []string) (*model.Post, error) {
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caption = strings.TrimSpace(caption)
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if caption == "" {
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return nil, errors.New("caption is required")
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}
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if len(caption) > 4000 {
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return nil, errors.New("caption too long (max 4000)")
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}
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sourceURL = stripHost(strings.TrimSpace(sourceURL))
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if sourceURL == "" || !strings.HasPrefix(sourceURL, "/") {
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return nil, errors.New("source_url must be an absolute path starting with /")
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}
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if len(imageURLs) > 5 {
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return nil, errors.New("a post can hold up to 5 images")
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}
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p, err := s.posts.Create(ctx, userID, caption, sourceURL, sourceTitle, imageURLs)
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if err != nil {
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return nil, err
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}
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// Tag mentioned users (best-effort, additive — a bad id never fails the
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// post itself). Reflect the count on the returned post, then notify the
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// tagged people (fire-and-forget on a detached context).
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if len(mentionUserIDs) > 0 {
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_ = s.mentions.AddMany(ctx, p.ID, mentionUserIDs)
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_ = s.mentions.HydrateCounts(ctx, []*model.Post{p})
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go s.notifyMentions(context.Background(), p.ID, userID, mentionUserIDs)
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}
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return p, nil
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}
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// Get returns one post (public). `viewerID` is "" for anonymous callers;
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// when set, the returned post carries the viewer's reshare state so the
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// frontend can render the right action button without a second request.
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func (s *PostService) Get(ctx context.Context, id, viewerID string) (*model.Post, error) {
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p, err := s.posts.FindByID(ctx, id)
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if err != nil {
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return nil, err
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}
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if err := s.hydrateReshareStates(ctx, viewerID, []*model.Post{p}); err != nil {
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return nil, err
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}
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if err := s.likes.Hydrate(ctx, viewerID, []*model.Post{p}); err != nil {
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return nil, err
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}
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if err := s.mentions.HydrateCounts(ctx, []*model.Post{p}); err != nil {
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return nil, err
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}
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if err := s.comments.HydratePinned(ctx, viewerID, []*model.Post{p}); err != nil {
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return nil, err
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}
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return p, nil
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}
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// Reshare materialises a reshare as a brand-new posts row owned by the
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// caller, with reshared_from_post_id pointing to the canonical original.
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// Idempotent — calling it twice returns the same reshare row. Resharing
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// one's own post (canonical or chained) is rejected at the repo layer.
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//
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// Returns the new post so the frontend can drop it into local state
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// without a round-trip.
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func (s *PostService) Reshare(ctx context.Context, postID, callerID string) (*model.Post, error) {
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return s.posts.Reshare(ctx, postID, callerID)
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}
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// Unreshare removes the caller's reshare of a canonical post by deleting
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// their own reshare posts row. Idempotent — no-ops when nothing to delete.
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func (s *PostService) Unreshare(ctx context.Context, postID, callerID string) error {
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return s.posts.Unreshare(ctx, postID, callerID)
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}
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// hydrateReshareStates fills in ViewerHasReshared on each post via one
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// batched lookup. Skips the query when the viewer is anonymous (the
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// answer is uniformly false) or the slice is empty.
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func (s *PostService) hydrateReshareStates(ctx context.Context, viewerID string, posts []*model.Post) error {
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if viewerID == "" || len(posts) == 0 {
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return nil
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}
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ids := make([]string, 0, len(posts))
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for _, p := range posts {
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if p == nil {
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continue
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}
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ids = append(ids, p.ID)
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}
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if len(ids) == 0 {
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return nil
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}
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states, err := s.posts.ReshareStatesFor(ctx, viewerID, ids)
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if err != nil {
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return err
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}
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for _, p := range posts {
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if p == nil {
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continue
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}
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if states[p.ID] {
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p.ViewerHasReshared = true
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}
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}
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return nil
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}
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// hydrateReshareStatesSlice is the value-slice variant of
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// hydrateReshareStates. Repository list methods return []model.Post
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// (not pointers) — we wrap each element so the helper can mutate in
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// place via a stable pointer.
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func (s *PostService) hydrateReshareStatesSlice(ctx context.Context, viewerID string, posts []model.Post) error {
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if len(posts) == 0 {
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return nil
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}
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ptrs := make([]*model.Post, len(posts))
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for i := range posts {
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ptrs[i] = &posts[i]
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}
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return s.hydrateReshareStates(ctx, viewerID, ptrs)
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}
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// Delete checks ownership and removes the post.
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func (s *PostService) Delete(ctx context.Context, postID, callerID string) error {
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return s.posts.Delete(ctx, postID, callerID)
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}
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// ReplaceImages swaps the image set on a post. Owner-only — every
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// reshare is its own posts row, owned by the resharer, so this works
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// uniformly for canonical posts and reshares.
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func (s *PostService) ReplaceImages(ctx context.Context, postID, callerID string, imageURLs []string) (*model.Post, error) {
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if err := s.posts.ReplaceImages(ctx, postID, callerID, imageURLs); err != nil {
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return nil, err
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}
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return s.posts.FindByID(ctx, postID)
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}
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// ListByHandle is the public feed view. `viewerID` is "" for anonymous
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// callers; when set, each returned post carries the viewer's reshare
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// state.
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func (s *PostService) ListByHandle(ctx context.Context, handle, viewerID string, limit, offset int) ([]model.Post, int, error) {
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if limit <= 0 || limit > 50 {
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limit = 20
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}
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if offset < 0 {
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offset = 0
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}
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posts, total, err := s.posts.ListByHandle(ctx, handle, limit, offset)
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if err != nil {
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return nil, 0, err
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}
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if err := s.hydrateReshareStatesSlice(ctx, viewerID, posts); err != nil {
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return nil, 0, err
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}
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if err := s.hydrateLikesSlice(ctx, viewerID, posts); err != nil {
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return nil, 0, err
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}
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if err := s.hydrateMentionsSlice(ctx, posts); err != nil {
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return nil, 0, err
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}
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if err := s.hydratePinnedSlice(ctx, viewerID, posts); err != nil {
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return nil, 0, err
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}
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return posts, total, nil
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}
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// hydratePinnedSlice fills PinnedComment on a value slice.
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func (s *PostService) hydratePinnedSlice(ctx context.Context, viewerID string, posts []model.Post) error {
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if len(posts) == 0 {
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return nil
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}
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ptrs := make([]*model.Post, len(posts))
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for i := range posts {
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ptrs[i] = &posts[i]
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}
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return s.comments.HydratePinned(ctx, viewerID, ptrs)
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}
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// hydrateLikesSlice fills LikesCount + ViewerHasLiked on a value slice.
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func (s *PostService) hydrateLikesSlice(ctx context.Context, viewerID string, posts []model.Post) error {
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if len(posts) == 0 {
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return nil
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}
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ptrs := make([]*model.Post, len(posts))
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for i := range posts {
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ptrs[i] = &posts[i]
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}
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return s.likes.Hydrate(ctx, viewerID, ptrs)
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}
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// hydrateMentionsSlice fills MentionsCount on a value slice.
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func (s *PostService) hydrateMentionsSlice(ctx context.Context, posts []model.Post) error {
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if len(posts) == 0 {
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return nil
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}
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ptrs := make([]*model.Post, len(posts))
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for i := range posts {
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ptrs[i] = &posts[i]
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}
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return s.mentions.HydrateCounts(ctx, ptrs)
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}
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// SuggestMentions returns prioritised mention suggestions for the composer.
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func (s *PostService) SuggestMentions(ctx context.Context, viewerID, q string, limit, offset int) ([]model.UserSummary, error) {
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return s.mentions.Suggest(ctx, viewerID, q, limit, offset)
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}
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// Mentions lists the users tagged on a post.
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func (s *PostService) Mentions(ctx context.Context, postID string) ([]model.UserSummary, error) {
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return s.mentions.ListForPost(ctx, postID)
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}
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// AddMention / RemoveMention edit a post's tags — author only.
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func (s *PostService) AddMention(ctx context.Context, viewerID, postID, targetUserID string) error {
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if err := s.requireAuthor(ctx, viewerID, postID); err != nil {
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return err
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}
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if err := s.mentions.Add(ctx, postID, targetUserID); err != nil {
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return err
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}
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if s.notif != nil {
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go s.notif.NotifyPostMention(context.Background(), targetUserID, viewerID, postID)
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}
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return nil
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}
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// notifyMentions notifies each freshly-tagged user (deduped, never the author).
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func (s *PostService) notifyMentions(ctx context.Context, postID, authorID string, userIDs []string) {
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if s.notif == nil {
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return
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}
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seen := make(map[string]bool, len(userIDs))
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for _, uid := range userIDs {
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if uid == "" || uid == authorID || seen[uid] {
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continue
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}
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seen[uid] = true
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s.notif.NotifyPostMention(ctx, uid, authorID, postID)
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}
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}
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func (s *PostService) RemoveMention(ctx context.Context, viewerID, postID, targetUserID string) error {
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if err := s.requireAuthor(ctx, viewerID, postID); err != nil {
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return err
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}
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return s.mentions.Remove(ctx, postID, targetUserID)
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}
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func (s *PostService) requireAuthor(ctx context.Context, viewerID, postID string) error {
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p, err := s.posts.FindByID(ctx, postID)
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if err != nil {
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return err
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}
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if p.UserID != viewerID {
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return ErrForbidden
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}
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return nil
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}
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// Like / Unlike toggle the caller's like on a post and return the effective
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// total (likes_count + pending Redis delta).
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func (s *PostService) Like(ctx context.Context, userID, postID string) (int, error) {
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changed, err := s.likes.Like(ctx, postID, userID)
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if err != nil {
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return 0, err
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}
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count, err := s.likes.EffectiveCount(ctx, postID)
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if err != nil {
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return 0, err
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}
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// Notify the author on a genuinely new like by someone else. Fire-and-
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// forget on a detached context so it isn't cancelled when the request
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// returns; NotifyPostLike re-checks self-like internally too.
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if changed && s.notif != nil {
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if authorID, aerr := s.likes.PostAuthor(ctx, postID); aerr == nil && authorID != userID {
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go s.notif.NotifyPostLike(context.Background(), postID, authorID, userID)
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}
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}
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return count, nil
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}
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func (s *PostService) Unlike(ctx context.Context, userID, postID string) (int, error) {
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if _, err := s.likes.Unlike(ctx, postID, userID); err != nil {
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return 0, err
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}
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return s.likes.EffectiveCount(ctx, postID)
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}
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// Likers returns one page of users who liked the post + the total count.
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func (s *PostService) Likers(ctx context.Context, postID, q string, limit, offset int) ([]model.UserSummary, int, error) {
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return s.likes.ListLikers(ctx, postID, q, limit, offset)
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}
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// ListMine is the owner's view of their own profile feed. Every post
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// they own — authored or reshared — comes from posts.user_id, so the
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// viewer is by construction the owner. ViewerHasReshared is true for
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// reshare rows (the user IS the resharer) and false for canonical
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// rows (you don't "reshare your own post").
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func (s *PostService) ListMine(ctx context.Context, userID string, limit, offset int) ([]model.Post, int, error) {
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if limit <= 0 || limit > 50 {
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limit = 20
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}
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if offset < 0 {
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offset = 0
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}
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posts, total, err := s.posts.ListByUser(ctx, userID, limit, offset)
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if err != nil {
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return nil, 0, err
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}
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for i := range posts {
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if posts[i].ResharedFromPostID != nil {
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posts[i].ViewerHasReshared = true
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}
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}
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if err := s.hydrateLikesSlice(ctx, userID, posts); err != nil {
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return nil, 0, err
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}
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if err := s.hydrateMentionsSlice(ctx, posts); err != nil {
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return nil, 0, err
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}
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if err := s.hydratePinnedSlice(ctx, userID, posts); err != nil {
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return nil, 0, err
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}
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return posts, total, nil
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}
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// ImagePresign returns a one-shot R2 PUT URL for a post image.
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// The key is namespaced under post-images/<user_id>/<random>.<ext>. We
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// don't tie it to a post_id at presign time because the post might not
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// exist yet — the user uploads images first, then submits the post with
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// the public URLs.
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func (s *PostService) ImagePresign(ctx context.Context, userID, contentType string) (uploadURL, publicURL string, err error) {
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return presignImage(ctx, s.r2, "post-images", userID, contentType)
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}
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// ---------------------------------------------------------------------------
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// BookmarkService
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// ---------------------------------------------------------------------------
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type BookmarkService struct {
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users *repository.UserRepo
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bookmarks *repository.BookmarkRepo
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}
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func NewBookmarkService(users *repository.UserRepo, bookmarks *repository.BookmarkRepo) *BookmarkService {
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return &BookmarkService{users: users, bookmarks: bookmarks}
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}
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// Create enforces the plan cap and inserts a new bookmark.
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//
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// If the same URL is already bookmarked (UNIQUE constraint), we return the
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// existing row as a 200 idempotent response instead of an error — clicking
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// "Bookmark" twice on the same passage should feel like a no-op.
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func (s *BookmarkService) Create(ctx context.Context, userID, sourceURL, sourceTitle string, excerpt, note *string) (*model.Bookmark, error) {
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u, err := s.users.FindByID(ctx, userID)
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if err != nil {
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return nil, err
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}
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current, err := s.bookmarks.CountByUser(ctx, userID)
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if err != nil {
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return nil, err
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}
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if err := EnforceBookmarkLimit(u.Plan, current); err != nil {
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return nil, err
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}
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b, err := s.bookmarks.Create(ctx, userID, stripHost(sourceURL), sourceTitle, excerpt, note)
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if err == nil {
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return b, nil
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}
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if errors.Is(err, repository.ErrBookmarkExists) {
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// Idempotent: return whatever is already there.
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list, lerr := s.bookmarks.ListByUser(ctx, userID)
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if lerr != nil {
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return nil, lerr
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}
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for _, existing := range list {
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if existing.SourceURL == stripHost(sourceURL) {
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return &existing, nil
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}
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}
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}
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return nil, err
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}
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// List returns the caller's bookmarks.
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func (s *BookmarkService) List(ctx context.Context, userID string) ([]model.Bookmark, error) {
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return s.bookmarks.ListByUser(ctx, userID)
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}
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// Delete removes a bookmark belonging to the caller.
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func (s *BookmarkService) Delete(ctx context.Context, id, userID string) error {
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return s.bookmarks.Delete(ctx, id, userID)
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}
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// ---------------------------------------------------------------------------
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// CollectionService
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// ---------------------------------------------------------------------------
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type CollectionService struct {
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users *repository.UserRepo
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collections *repository.CollectionRepo
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posts *repository.PostRepo
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r2 *repository.R2
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}
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func NewCollectionService(users *repository.UserRepo, collections *repository.CollectionRepo, posts *repository.PostRepo, r2 *repository.R2) *CollectionService {
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return &CollectionService{users: users, collections: collections, posts: posts, r2: r2}
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}
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// Create enforces per-visibility plan caps and inserts.
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func (s *CollectionService) Create(ctx context.Context, userID, title string, description, coverURL *string, isPublic bool) (*model.CollectionRecord, error) {
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if title = strings.TrimSpace(title); title == "" {
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return nil, errors.New("title is required")
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}
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if len(title) > 120 {
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return nil, errors.New("title too long (max 120)")
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}
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u, err := s.users.FindByID(ctx, userID)
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if err != nil {
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return nil, err
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}
|
||
current, err := s.collections.CountByUserAndVisibility(ctx, userID, isPublic)
|
||
if err != nil {
|
||
return nil, err
|
||
}
|
||
if err := EnforceCollectionLimit(u.Plan, isPublic, current); err != nil {
|
||
return nil, err
|
||
}
|
||
return s.collections.Create(ctx, userID, title, description, coverURL, isPublic)
|
||
}
|
||
|
||
// Update — only the owner may edit. Visibility changes that would exceed
|
||
// the plan cap are blocked.
|
||
func (s *CollectionService) Update(ctx context.Context, id, userID string, title, description, coverURL *string, isPublic *bool) (*model.CollectionRecord, error) {
|
||
c, err := s.collections.FindByID(ctx, id)
|
||
if err != nil {
|
||
return nil, err
|
||
}
|
||
if c.UserID != userID {
|
||
return nil, ErrForbidden
|
||
}
|
||
// If the caller is flipping visibility, make sure they wouldn't blow the cap.
|
||
if isPublic != nil && *isPublic != c.IsPublic {
|
||
u, err := s.users.FindByID(ctx, userID)
|
||
if err != nil {
|
||
return nil, err
|
||
}
|
||
current, err := s.collections.CountByUserAndVisibility(ctx, userID, *isPublic)
|
||
if err != nil {
|
||
return nil, err
|
||
}
|
||
if err := EnforceCollectionLimit(u.Plan, *isPublic, current); err != nil {
|
||
return nil, err
|
||
}
|
||
}
|
||
return s.collections.Update(ctx, id, userID, title, description, coverURL, isPublic)
|
||
}
|
||
|
||
// Delete — only the owner may delete.
|
||
func (s *CollectionService) Delete(ctx context.Context, id, userID string) error {
|
||
c, err := s.collections.FindByID(ctx, id)
|
||
if err != nil {
|
||
return err
|
||
}
|
||
if c.UserID != userID {
|
||
return ErrForbidden
|
||
}
|
||
return s.collections.Delete(ctx, id, userID)
|
||
}
|
||
|
||
// ListMine returns the caller's collections (both public and private).
|
||
func (s *CollectionService) ListMine(ctx context.Context, userID string) ([]model.CollectionRecord, error) {
|
||
return s.collections.ListByUser(ctx, userID)
|
||
}
|
||
|
||
// AddItem inserts a post into a collection. Caller must own the collection.
|
||
// We don't require ownership of the *post* — collections can curate other
|
||
// users' public posts in a future iteration; for v1 the toolbar always
|
||
// creates a fresh post owned by the caller before calling this.
|
||
func (s *CollectionService) AddItem(ctx context.Context, collectionID, postID, callerID string) error {
|
||
c, err := s.collections.FindByID(ctx, collectionID)
|
||
if err != nil {
|
||
return err
|
||
}
|
||
if c.UserID != callerID {
|
||
return ErrForbidden
|
||
}
|
||
if _, err := s.posts.FindByID(ctx, postID); err != nil {
|
||
return err
|
||
}
|
||
return s.collections.AddItem(ctx, collectionID, postID)
|
||
}
|
||
|
||
// SetItemOrder updates positions for the given post ids so the new order
|
||
// matches the input array. Owner-only.
|
||
func (s *CollectionService) SetItemOrder(ctx context.Context, collectionID, callerID string, postIDs []string) error {
|
||
c, err := s.collections.FindByID(ctx, collectionID)
|
||
if err != nil {
|
||
return err
|
||
}
|
||
if c.UserID != callerID {
|
||
return ErrForbidden
|
||
}
|
||
return s.collections.SetItemOrder(ctx, collectionID, postIDs)
|
||
}
|
||
|
||
// CollectionsContaining returns the ids of the caller's collections
|
||
// that already include the given post. Used by the save-to-collection
|
||
// drawer to disable rows the post is already in.
|
||
func (s *CollectionService) CollectionsContaining(ctx context.Context, postID, callerID string) ([]string, error) {
|
||
return s.collections.CollectionsContaining(ctx, postID, callerID)
|
||
}
|
||
|
||
// RemoveItem detaches a post from a collection (owner only).
|
||
func (s *CollectionService) RemoveItem(ctx context.Context, collectionID, postID, callerID string) error {
|
||
c, err := s.collections.FindByID(ctx, collectionID)
|
||
if err != nil {
|
||
return err
|
||
}
|
||
if c.UserID != callerID {
|
||
return ErrForbidden
|
||
}
|
||
return s.collections.RemoveItem(ctx, collectionID, postID)
|
||
}
|
||
|
||
// Get returns one collection. Visibility is enforced by the caller —
|
||
// `viewerID` is the calling user id ("" if anonymous). If the collection is
|
||
// private and the viewer isn't the owner, returns ErrForbidden.
|
||
func (s *CollectionService) Get(ctx context.Context, id, viewerID string) (*model.CollectionRecord, []model.Post, error) {
|
||
c, err := s.collections.FindByID(ctx, id)
|
||
if err != nil {
|
||
return nil, nil, err
|
||
}
|
||
if !c.IsPublic && c.UserID != viewerID {
|
||
return nil, nil, ErrForbidden
|
||
}
|
||
posts, err := s.collections.PostsIn(ctx, id)
|
||
if err != nil {
|
||
return nil, nil, err
|
||
}
|
||
// PostsIn returns posts without images (single-table boundary). Hydrate
|
||
// them in one batched query so callers — and the post cards rendered
|
||
// inside collection carousels — can show the post's first image as
|
||
// background instead of falling back to the empty quote panel.
|
||
if len(posts) > 0 {
|
||
ids := make([]string, len(posts))
|
||
for i := range posts {
|
||
ids[i] = posts[i].ID
|
||
}
|
||
imgs, err := s.posts.ImagesFor(ctx, ids)
|
||
if err != nil {
|
||
return nil, nil, err
|
||
}
|
||
for i := range posts {
|
||
posts[i].Images = imgs[posts[i].ID]
|
||
}
|
||
// Same batched approach for reshare states so the action footer
|
||
// on each card swaps Reshare↔Send correctly. Anonymous viewers
|
||
// (viewerID == "") get all-false at zero cost.
|
||
if viewerID != "" {
|
||
states, err := s.posts.ReshareStatesFor(ctx, viewerID, ids)
|
||
if err != nil {
|
||
return nil, nil, err
|
||
}
|
||
for i := range posts {
|
||
if states[posts[i].ID] {
|
||
posts[i].ViewerHasReshared = true
|
||
}
|
||
}
|
||
}
|
||
}
|
||
return c, posts, nil
|
||
}
|
||
|
||
// CoverPresign returns a one-shot R2 PUT URL for a collection cover image.
|
||
func (s *CollectionService) CoverPresign(ctx context.Context, userID, contentType string) (uploadURL, publicURL string, err error) {
|
||
return presignImage(ctx, s.r2, "collection-covers", userID, contentType)
|
||
}
|
||
|
||
// ---------------------------------------------------------------------------
|
||
// shared helpers
|
||
// ---------------------------------------------------------------------------
|
||
|
||
// presignImage builds an R2 presign for a user-scoped media key under the
|
||
// given prefix. The random suffix invalidates browser caches when the image
|
||
// is replaced.
|
||
func presignImage(ctx context.Context, r2 *repository.R2, prefix, userID, contentType string) (uploadURL, publicURL string, err error) {
|
||
if r2 == nil {
|
||
return "", "", errors.New("media uploads are not configured")
|
||
}
|
||
ext, ok := imageExtensionFor(contentType)
|
||
if !ok {
|
||
return "", "", fmt.Errorf("unsupported content type: %s", contentType)
|
||
}
|
||
suffix := make([]byte, 8)
|
||
if _, err := rand.Read(suffix); err != nil {
|
||
return "", "", err
|
||
}
|
||
key := path.Join(prefix, userID, hex.EncodeToString(suffix)+ext)
|
||
return r2.PresignPut(ctx, key, contentType, 5*time.Minute)
|
||
}
|
||
|
||
func imageExtensionFor(ct string) (string, bool) {
|
||
switch ct {
|
||
case "image/png":
|
||
return ".png", true
|
||
case "image/jpeg":
|
||
return ".jpg", true
|
||
case "image/webp":
|
||
return ".webp", true
|
||
case "image/gif":
|
||
return ".gif", true
|
||
default:
|
||
return "", false
|
||
}
|
||
}
|
||
|
||
// stripHost reduces "https://prabhupadasays.org/books/bg/1/1?hl=x" to
|
||
// "/books/bg/1/1?hl=x" so we never store arbitrary external URLs.
|
||
// Anything that doesn't parse cleanly is returned unchanged (and rejected
|
||
// later by the prefix-check in the service).
|
||
func stripHost(u string) string {
|
||
u = strings.TrimSpace(u)
|
||
if u == "" {
|
||
return u
|
||
}
|
||
if strings.HasPrefix(u, "/") {
|
||
return u
|
||
}
|
||
for _, prefix := range []string{"http://", "https://"} {
|
||
if strings.HasPrefix(u, prefix) {
|
||
rest := u[len(prefix):]
|
||
if i := strings.IndexByte(rest, '/'); i >= 0 {
|
||
return rest[i:]
|
||
}
|
||
return "/"
|
||
}
|
||
}
|
||
return u
|
||
}
|