# Combobox (Lumen Halo): prompt.md (v1.0.0)

- id: `lumen-combobox` · version 1.0.0 · component · pro (All-Access)
- category: Selection
- build: Base UI (this item also ships a Radix build)
- install (this build): `npx shadcn@latest add @beautiful-ui-pro/lumen-combobox`
- npm dependencies: @base-ui/react@^1
- registry dependencies: utils, @beautiful-ui/lumen-input-group, https://beautiful-ui.dev/r/lumen-foundation.json
- docs: https://beautiful-ui.dev/components/lumen-combobox
- The install command carries everything this item needs (files, CSS, tokens, npm and registry dependencies). Prefer it to copying source by hand.

Type to narrow a long list: the matches sit in smoked glass where a lens of light glides to the highlighted one. With chips it becomes a multi-select, each pick a small lit cell you can remove. shadcn's Combobox, cut from Lumen glass.

## Build it
- Stack: React 19 (`ref` is a plain prop), TypeScript, Tailwind CSS v4 utilities, a shadcn-initialised project with the `@/*` alias.
- Packages: `@base-ui/react@^1`.
- Files: `components/ui/lumen/combobox.tsx`; shared code: `lib/beautiful-ui/lumen/portal.ts`, `lib/beautiful-ui/lumen/glyphs.tsx`, `lib/beautiful-ui/lumen/indicator.ts`, `lib/beautiful-ui/lumen/sound.ts`.
- Registry dependencies, installed with it automatically: shadcn `utils` (cn), `lumen-input-group`, `lumen-foundation`.
- Builds: separate Base UI and Radix files. Install the one that matches the project (see Install): a free item's bare URL installs the Base UI build of it and its dependencies.
- Exports to keep: `Combobox`, `ComboboxInput / ComboboxTrigger / ComboboxClear`, `ComboboxContent / ComboboxList / ComboboxItem`, `ComboboxChips / ComboboxChip / ComboboxChipsInput`, `ComboboxEmpty / ComboboxGroup / ComboboxLabel / ComboboxSeparator / ComboboxCollection`, and every exported type.
- CSS: the install merges this item's rules (the registry `css` field) into your global stylesheet, in `@layer components`, and adds the lumen foundation (tokens, keyframes, motion levels) once. Nothing to import by hand.
- Re-running `add` (or `--overwrite`) re-applies those rules: put overrides in your own CSS, never in the installed rules.
- Tokens: retheme with the `--lumen-*` custom properties (`--lumen-accent`, `--lumen-accent-text`, `--lumen-bad`, `--lumen-bad-text`, `--lumen-focus`, `--lumen-good`, `--lumen-good-text`, `--lumen-hairline`, `--lumen-ink`, `--lumen-muted-ink`, `--lumen-series-1`, `--lumen-series-2`, `--lumen-series-3`, `--lumen-series-4`, `--lumen-series-5`, `--lumen-series-6`, `--lumen-warn`, `--lumen-warn-text`); this item's CSS also reads `--lumen-font-mono`, `--lumen-font-sans`, `--lumen-radius-k`. Never add Tailwind colour classes inside the component.

```tsx
import { Combobox, ComboboxContent, ComboboxEmpty, ComboboxInput, ComboboxItem, ComboboxList } from "@/components/ui/lumen/combobox";
```

## Parts

| Part | data-slot | What it is for |
|---|---|---|
| `Combobox` | — | Root (Base UI in both builds, as shadcn). |
| `ComboboxInput / ComboboxTrigger / ComboboxClear` | `combobox-trigger` | The well you type in. |
| `ComboboxContent / ComboboxList / ComboboxItem` | `combobox-content` | The glass with the lens and the matches. |
| `ComboboxChips / ComboboxChip / ComboboxChipsInput` | `combobox-chips` | Multi-select. |
| `ComboboxEmpty / ComboboxGroup / ComboboxLabel / ComboboxSeparator / ComboboxCollection` | `combobox-empty` | Structure. |

Style a part with `[data-slot="<slot>"]` selectors or its `className`; keep the attributes when editing.

## Sound
- Keep every `data-slot` and `data-sound` attribute: the sound layer reads them.
- Installing this item adds no audio. Nothing plays until the app mounts `GlassSoundProvider` once (install: `npx shadcn@latest add https://beautiful-ui.dev/r/glass-sound.json`, import from `@/components/beautiful-ui/glass-sound`); `GlassSoundToggle` is its mute control. Without a provider the audio engine never loads.

## Match the original
- Read `components/ui/lumen/combobox.tsx` as the reference implementation before changing or recreating anything, and match it: sizes, colours per theme, motion timings, copy and behaviour.
- If you deviate (a prop you can't honour, a style you changed, a dependency you swapped), say so in your reply, part by part.
- Keep the accessibility contract, the keyboard map and the motion levels listed below.

## Use it when
- combobox, autocomplete, searchable select, multi select, tag picker, chips input, typeahead, shadcn combobox, Lumen
- Choosing from a list too long to scan (countries, customers, owners)
- Picking several values as chips (segments, tags, plans)

### Not when
- Five options or fewer: use Select or Radio Group
- Free text that isn't picked from a list: use Input

## Mistakes
- Always give ComboboxEmpty words that say what to try instead

## Usage

```tsx
import { Combobox, ComboboxContent, ComboboxEmpty, ComboboxInput, ComboboxItem, ComboboxList } from "@/components/ui/lumen/combobox";

<Combobox items={owners}>
  <ComboboxInput placeholder="Assign an owner" />
  <ComboboxContent>
    <ComboboxEmpty>No one by that name.</ComboboxEmpty>
    <ComboboxList>{(owner) => <ComboboxItem key={owner} value={owner}>{owner}</ComboboxItem>}</ComboboxList>
  </ComboboxContent>
</Combobox>
```

## Props

| Prop | Type | Default | What it does |
|---|---|---|---|
| `Combobox items / multiple` | `T[] / boolean` |  | The options; multiple makes it a multi-select (use ComboboxChips). |
| `ComboboxInput showTrigger / showClear` | `boolean` | `true / false` | The chevron and the clear button in the well. |
| `ComboboxContent anchor` | `Ref` |  | Anchor the popup to the chips (useComboboxAnchor). |
| `ComboboxChip showRemove` | `boolean` | `true` | The quiet remove on each chip. |

Full docs: https://beautiful-ui.dev/components/lumen-combobox

## Customising
- Colours: set the `--lumen-*` tokens on `:root`, or on a container with the `lumen-scope` class to retheme one area. Add the `lumen-inherit` class to follow your shadcn palette instead (`--chart-N`, `--destructive`).
- Dark mode follows the `.dark` class on an ancestor (the shadcn and next-themes convention).
- Update later by re-running the install with `--overwrite` (review the diff if you edited it). Changelog: https://beautiful-ui.dev/r/changelog.json

## Keyboard

| Keys | Action |
|---|---|
| ↑ ↓ | Move; the lens follows |
| Enter | Pick |
| Backspace | Remove the last chip (multi) |
| Escape | Close |

## Motion inventory

| Interaction | What moves |
|---|---|
| Highlight | The lens glides to the option (.35s spring) |
| Pick (multi) | A chip grows in from its cell |

## Accessibility contract (preserve when editing)
- role=combobox with a listbox; the highlighted option is announced
- Chips are reachable with arrow keys and removable with Backspace

## Install

```bash
npx shadcn@latest add @beautiful-ui-pro/lumen-combobox
```

Pro item: needs the `@beautiful-ui-pro` registry in `components.json` and `BEAUTIFUL_UI_TOKEN` in `.env.local` (https://beautiful-ui.dev/account). Setup: https://beautiful-ui.dev/docs/pro. Your components.json `style` picks the build: radix-*, new-york and default get Radix, base-* gets Base UI.

## Credits
- Built on shadcn/ui (https://ui.shadcn.com)
- Base UI Combobox (https://base-ui.com/react/components/combobox)

The lumen foundation (the tokens listed above, keyframes and motion levels) installs once with the first component; its CSS is public at https://beautiful-ui.dev/r/lumen-foundation.json.