platform/THEMES-NOTES.md

# Themes decoupling — working notes

Branch `themes-decoupling`, worktree `platform-themes`. Nothing here is on master.

Read this before the diff. It is the state of the work, the decisions taken and why, and the things
deliberately left alone.

---

## Where it got to

The visual layer is out of the app and into `src/workspaces/theme`. The application no longer contains any
colour: it imports one stylesheet and mounts one provider.

Proven by the two things that matter:

- **Duck renders identically to before.** Panels, wallpaper, grid fills, glass, logo — checked against
  screenshots taken before anything was touched.
- **Plain renders as white with black ink**, with no component edits. Panels turn white, the teal avatar
  turns black, grid fills disappear. That is the decoupling working.

Switch themes from the avatar menu, top right.

---

## The shape

```
src/workspaces/theme/
  css/base.css              structure — Tailwind, the @theme contract, element defaults. NO values.
  css/themes/duck-light.css  the app's original appearance, moved unchanged
  css/themes/duck-dark.css   ditto, the old .dark block
  css/themes/plain.css       white/black — an instrument, not a design
  css/chrome.css            scrollbars and overlays, now in theme variables
  css/index.css             the single import an app makes
  src/themes.ts             the registry: id, name, family, applyDarkClass. Nothing about appearance.
  src/ThemeProvider.tsx     sets data-theme, toggles .dark, persists the choice
```

A theme is a CSS file scoped to `[data-theme='<id>']` plus one line in the registry. Nothing else.

---

## Decisions, and why

**Light and dark are separate themes, not a mode.** The owner's call, and it removes a concept from the
app. `Duck Light` and `Duck Dark` are siblings. Written out in full rather than as a diff — a theme that
only makes sense in the presence of another cannot be authored by a third party or sold to a customer.

**`.dark` survives as a compatibility flag.** 396 `dark:` utilities are written into 33 components and they
resolve against that class. A theme sets `applyDarkClass` and they keep working. Shim with a known end
date; removing those 396 retires it.

**`duck-*` utility names are kept, pointed at neutral variables.** ~1,470 occurrences across 108 files.
Renaming them and extracting in the same change would make a visual difference impossible to attribute.
They now resolve through `--brand-primary`, `--ink`, and friends, so a non-Duck theme can define them
sensibly even while the spelling is wrong.

**`duck-dark` is `--ink`.** It was never a brand colour: `#14532d` in light, near-white in dark. 946
components use it to mean "text". That misnaming is why it is the most-used token in the app.

**Surfaces are complete CSS values, not HSL triplets.** `--panel-bg` can be `rgba()`, a gradient or an
image. A panel background that could only be a flat colour would rule out the glass the app has now.

**The old provider file is a re-export.** Six call sites keep working untouched, so the extraction is one
variable.

---

## Blockers and open questions — for the morning

**1. The reference repo (`vimazing`) has not been read yet.** The switching mechanism (`data-theme` on
`<html>`) and the packaging format are deliberately the dumbest thing that works, because that repo will
dictate them. Everything above is independent of that choice.

**2. Leaks the Plain theme exposed.** These are components painting themselves rather than asking the
theme. The screenshots in `.snapshots/plain/` are the punch list:

- **The wallpaper.** Still renders under Plain, so it is set by a component, not `--page-bg`. Probably the
  dashboard layout. Needs to become a theme-owned surface.
- **Panel radius.** `--panel-radius: 0` had no effect — panels hardcode `rounded-*`. Shape is themeable in
  principle and is not yet.
- **The logo.** A fixed image. Fine for Duck, wrong for white-labelling: a customer's build needs its own.
- **~985 raw Tailwind palette usages** (`text-emerald-400`, `bg-black/10`) and **~119 hex literals**. The
  worst concentration by far is `officerdev/src/apps/Soulseek/` (~285). `MetricCard.tsx` is the
  highest-leverage single fix — a shared component hardcoding its palette.

**3. Server settings still store `appearance.colorMode`, not a theme id.** `useThemeSync` used to stamp the
server's colour mode over the local theme on every load — picking Plain and reloading silently reverted it.
Now the server value is only honoured when the browser has never chosen. The proper fix is storing a theme
id, which needs a settings migration.

**4. A pre-existing bug, unrelated but adjacent.** The server's default is `appearance: { theme: 'light' }`
while the client reads `appearance.colorMode` — so a fresh account's server default has never been read.
Left alone.

**5. `rebuildFrontend()` reports `"Bundle failed"` and discards the bundler's actual errors.** Cost twenty
minutes tonight. Same shape as the agent bugs from earlier — a failure that refuses to say why.

**6. Theme ASSETS have no packaging story yet — deferred deliberately.** A theme publishes an asset as a
quoted path (`--logo-src: '/officer-logo.svg'`) and `useThemeAsset` wraps it, because Bun's CSS bundler
resolves `url()` at build time while these files are served from `public/` at runtime. That works for
themes we ship. It does not answer where a THIRD PARTY's wallpaper and logo live. The owner's intent is a
convention under `public/` — something like `public/themes/<name>/` — so an author drops files in a known
structure and references them by path. Not designed yet; the token shape above already fits it.

**7. Landing and marketplace are untouched.** They have their own copies of the palette; `duck-teal` has
three different definitions across the three apps. Folding them into this layer is a natural follow-up and
was not in tonight's scope.

---

## On verification, and what the screenshots can and cannot tell you

The byte comparison is **dominated by wallpaper noise**. The dashboard background rotates per page load, so
any screen showing it differs from itself between runs — a control capture of the same build against itself
had 4 of 16 differ, and which 4 changes each time. Between 5 and 6 screens come out byte-identical to the
pre-refactor baseline on any given run; the rest are the wallpaper.

So the authoritative instrument is `scripts/theme-vardiff.ts`, which compares the COMPUTED value of every
theme variable between the old and new builds in the same colour mode. It reports **all 53 identical**.
That is a much stronger statement than a screenshot: it says the token layer resolves to exactly the values
the old stylesheet produced.

It also found the one real regression, which no amount of looking would have: six `--duck-*` variables came
out EMPTY in the new build. The utilities were remapped, but `prose.css` reads `var(--duck-teal)` DIRECTLY
in eleven places for chat markdown — links, blockquotes, inline code, checkboxes — and `landing/styles.css`
does the same. Fixed by keeping the legacy names as aliases in every theme, which also protects any plugin
or inline style doing the same thing. They retire with the utility rename.

## Tools built

- `scripts/theme-snapshot.ts` — captures 8 routes × 2 modes, or a pinned theme with `--theme`. Compares two
  directories byte-for-byte. Its first version silently photographed light twice; it now warns when a
  light/dark pair is identical.
- `scripts/theme-vardiff.ts` — computed theme variables, old build vs new, side by side. The instrument
  that actually proved the extraction faithful.
- `scripts/theme-preview-server.ts` — serves this worktree's build against the RUNNING platform's API, so
  the new frontend can be seen with real data without starting a second platform beside the live one.

Byte comparison is too strict for before/after across two builds: this worktree has no plugins, so the dock
differs on every page, and live data moves between captures. Use it to find *which* screens changed, then
look at them.