# Wiki Mode / Multi-Editor — Technical Implementation

_Generated 2025-08-22_

## Data Model

**BlogSettings**

- `wikiEnabled: boolean` (optional; missing = false)
- `editorWhitelist: Name[]` (optional; empty = global allow)
- `editorBlacklist: Name[]` (optional)

**Post (revision)**

- `originPostId: Id` (first ancestor; fallback to id if missing)
- `parentPostId?: Id`
- `lineageBlogId: BlogId` (owner’s blog id; fallback to route blog id)
- `authorName: Name` (registered name)
- `updatedAt: ISO timestamp` (fallback to QDN timestamp if missing)
- `published: boolean`

## Authorization (by Name)

1. Owner always allowed.
2. Blacklist blocks regardless.
3. Whitelist non-empty → only listed Names (minus blacklist).
4. Whitelist empty → all Names allowed (minus blacklist).

## canEdit(viewerName, settings, ownerName)

- Returns true if viewerName is Owner, or if wiki enabled and viewerName passes the whitelist/blacklist rules.

## Canonical Resolver (client)

1. Resolve origin id.
2. Collect revisions with same origin + blog lineage, published = true.
3. Filter by authorization (authorName vs blog settings).
4. Pick newest by updatedAt; tiebreak: Owner wins; then lowest id.

Reference implementation in code:

- `src/utils/wiki.ts` provides `isAuthorized`, `canEdit`, and `selectCanonical` used across UI.
- `src/utils/wikiSettingsCache.ts` caches per-blog (ownerName, settings) using `/arbitrary/resources?service=BLOG&identifier=...` and `/arbitrary/BLOG/<owner>/<id>`.
- `src/hooks/useFetchPosts.tsx` groups search results by identifier and applies canonical selection in feed, favorites, and subscriptions.
- `src/pages/BlogIndividualPost/BlogIndividualPost.tsx` resolves canonical author before fetching BLOG_POST JSON when wiki mode is enabled.

## UI

- Blog Settings: toggle, Name pickers for whitelist/blacklist.
  - Implemented in `Edit Blog` modal (checkbox + comma-separated Name inputs).
  - Also available in `Create Blog` modal so new blogs can enable wiki from the start.
- Post page: “Latest by Name on Date” subheader if revision not by Owner.
- Edit: shown only if canEdit true.
- Blog list: use resolver to show canonical per lineage.
  - Global feed, Subscriptions, and Favorites use a lightweight cache of per-blog settings to canonicalize duplicates by identifier.
  - Header blog switcher seeds blog context to ensure the posts list refreshes immediately on change.

## Backward Compatibility

- Missing fields → defaults (wikiEnabled=false, lists empty, origin=id, lineage=blogId, updatedAt=QDN ts).

## Performance Notes

- Settings Resolution: reads wiki settings from BLOG resource metadata when available; otherwise fetches BLOG JSON as fallback.
- Prefetch: for each page of results, settings for blogs with duplicate identifiers are prefetched in parallel (singletons skip resolution).
- Canonicalization happens only when necessary; otherwise owner or newest item is used.

## Edit Flow (Wiki)

- **Editors do not need their own blog** to publish a revision of an existing post when the target blog has Wiki Mode enabled.
- Edits publish a new `BLOG_POST` under the editor's **Name** using the **original BLOG_POST identifier**; the canonical resolver selects the visible revision.
- Blog (`service: BLOG`) metadata is **not** republished during edits.