The file viewer converts word-processor documents to PDF server-side via
LibreOffice (skald_core::docx::DocxConverter), mirroring the LaTeX pipeline
but content-hash cached: the format is self-contained, so there is no
dependency graph and the file watcher needs no expansion. Container-only
documents are shuttled out and converted on the host. With no LibreOffice
installed the viewer says so and falls back to download-only. Downloads
still save the original document, not the preview PDF.
An eye next to the paperclip shares what the user has open with their next
message: the page, the folder being browsed, the file open in the viewer and
any highlighted passage (line numbers where a source view exists), plus which
entity a detail page is about. The bag is client-authored {label, value} pairs
in English — the backend only clamps (chars, never bytes), neutralizes the
harness tag and renders one <system-extra> block per message, deduped
consecutively so it appears exactly when the view changed. On by default,
per-device toggle, hover/tap to preview, a chip on every sent message;
docs/view-context.md for users, an updated harness.md clause for the model.
Vendor highlight.js (core + python, javascript, typescript, json, yaml,
bash) and highlight the file viewer's text kind (computed once per load)
plus fenced blocks in renderMarkdown. Colors come from new --syn-* CSS
variables aliased to the existing palette, so dark mode follows.
A clock button in the file viewer header lists the versions of a file
whose project keeps a git history; picking one shows the file as of
that commit, read-only, with a banner back to the current version.
A past version is never served from the working tree: the whole
repository is materialized at that revision (git archive streamed
through tar into a size-bounded, immutable-by-rev cache) and every
fetch — content, compiled LaTeX, markdown images, downloads — resolves
inside that tree, so dependencies are contemporaneous with the file:
a .tex compiles against its \input's and images of that moment.
Backend: new git_versions module (repo discovery bounded by the
workspace mount, host-git log/rev-parse/archive, extraction cache with
oldest-first prune) + GET /api/file/versions and a rev param on
GET /api/file (rev is the ETag; never X-Writable). Frontend: history
mode in FileViewerBase shared by the desktop and mobile viewers —
popover, banner, watcher paused while browsing, rev propagated to
every /api/file URL it builds.
On iOS the file viewer showed only the first page of a PDF, with no way
to scroll to the rest — the document had to be downloaded and opened in
another app. The cause was not ours: WebKit refuses to mount its PDF
viewer inside an <iframe>/<object>/<embed> and paints a static first-page
thumbnail instead. That hits Safari on iOS and every WKWebView, so the
native shell too. The full viewer only exists for a top-level navigation.
The desktop browsers do mount a viewer, but each mounts its own — Chrome's
toolbar, Safari's page-index sidebar — so the same document also looked
different on every machine.
Both are answered by drawing the pages ourselves. New <pdf-view>
(web/components/shared/pdf-view.js) renders a continuous scroll of canvas
pages on the vendored pdf.js, with a zoom control and a page counter, and
replaces the iframe for both native .pdf files and server-compiled LaTeX.
Three properties are load-bearing:
- pdf.js is imported lazily (~450 KB + a 1.2 MB worker), so a session that
never opens a PDF never pays for it.
- Canvases are created and destroyed as pages scroll. iOS caps the total
canvas backing store a page may hold and silently blanks canvases past
it, so an eager render would come out empty on exactly the platform this
was written for. Off-screen pages keep only a correctly-sized box, which
is also what keeps the scrollbar honest.
- The text layer (selection, in-page find) is best-effort: it is
transparent DOM over the pixels, so its failures are swallowed rather
than surfaced.
Vendored from pdfjs-dist 6.2.108: pdf.min.mjs, pdf.worker.min.mjs, the
standard-font data (needed by PDFs that reference Helvetica/Times without
embedding them) and the .textLayer block of pdf_viewer.css. CJK cmaps are
deliberately left out. pdf.js 6 needs Safari/iOS 17.4+.
Verified in headless Chromium against both a synthetic 12-page PDF using
non-embedded Helvetica and a real 14-page paper with embedded fonts and
figures: all pages present, last page renders after scrolling, page 1
released off-screen, text layer populated, zoom re-renders at the new
scale, no JS errors.
The watch callback forwarded every FS event, including the pure reads the
viewer's own GET /api/file produces (IN_ACCESS / IN_CLOSE_NOWRITE on Linux):
each silent reload re-triggered the watcher, looping at ~1 Hz. For PDFs every
iteration minted a new blob URL and re-assigned iframe.src, which re-runs
Chrome's whole PDF viewer (the flicker) and pushes a joint session-history
entry (the back button buried under hundreds of blob: entries).
- file_watch: forward an event only when the content version (mtime_ns, len)
actually moved; drop Access events outright, stat-compare the rest.
- viewer: render pdf/latex/svg previews in a keyed() iframe — a fresh
element's first navigation replaces its history slot instead of pushing.
- GET /api/file returns ETag (mtime+size) + X-Writable on disk files;
PUT /api/file accepts optional if_match -> 409 Conflict on stale version
(last-write-wins preserved when omitted), echoes the new ETag
- FileViewerBase: View | Edit tabs for .md when the caller can write;
source textarea with Save/Cancel, live preview while editing
- Watcher no longer clobbers the buffer mid-edit: while editing with
unsaved changes it probes the server ETag and only raises a conflict
when the remote actually moved on (own-save echo is ignored)
- Conflict banner: Reload remote | Copy mine, then reload | Overwrite
- i18n (en/it/fr) + CSS; docs/projects.md updated
Daniele
dguiducci