# Toes - Guide to Writing Apps

Toes manages and runs web apps, each on its own port. 

Apps are server-rendered TypeScript using **Hype** (wraps Hono) and **Forge** (CSS-in-JS). 

Runtime is **Bun**.

## Required Components

Every toes app/tool must have:

1. **`.npmrc`** pointing to `registry=https://npm.nose.space` (the private registry for `@because/*` packages)
2. **`package.json`** with a `scripts.toes` entry (this is how toes discovers and runs apps)
3. **HTTP `GET /ok`** returning 200 (health check endpoint — toes polls this every 30s and restarts unresponsive apps)

## App vs Tool

An **app** shows in the sidebar and opens in its own browser tab.

A **tool** renders as a tab inside the dashboard (in an iframe). It receives `?app=<name>` to know the selected app. The only code difference is `"toes": { "tool": true }` in package.json and some extra imports from `@because/toes`.

## Required Files

Every app needs `.npmrc`, `tsconfig.json`, `package.json`, and `index.tsx`.

**.npmrc** -- always this exact content:
```
registry=https://npm.nose.space
```

**tsconfig.json** -- use exactly, do not improvise:
```json
{
  "compilerOptions": {
    "lib": ["ESNext"],
    "target": "ESNext",
    "module": "Preserve",
    "moduleDetection": "force",
    "jsx": "react-jsx",
    "jsxImportSource": "hono/jsx",
    "allowJs": true,
    "moduleResolution": "bundler",
    "allowImportingTsExtensions": true,
    "verbatimModuleSyntax": true,
    "noEmit": true,
    "strict": true,
    "skipLibCheck": true,
    "noFallthroughCasesInSwitch": true,
    "noUncheckedIndexedAccess": true,
    "noImplicitOverride": true,
    "noUnusedLocals": false,
    "noUnusedParameters": false,
    "noPropertyAccessFromIndexSignature": false,
    "baseUrl": ".",
    "paths": {
      "$*": ["src/server/*"],
      "#*": ["src/client/*"],
      "@*": ["src/shared/*"]
    }
  }
}
```

**package.json** for an app:
```json
{
  "name": "my-app",
  "private": true,
  "module": "index.tsx",
  "type": "module",
  "scripts": { "toes": "bun run --watch index.tsx" },
  "toes": { "icon": "🖥️" },
  "dependencies": {
    "@because/forge": "*",
    "@because/hype": "*"
  },
  "devDependencies": { "@types/bun": "latest" }
}
```

For a **tool**, add `@because/toes` to dependencies and set `"tool": true` (or a string for a custom tab label like `"tool": ".env"`):
```json
{
  "toes": { "icon": "🔧", "tool": true },
  "dependencies": {
    "@because/forge": "*",
    "@because/hype": "*",
    "@because/toes": "*"
  }
}
```

## Hype

Hype wraps Hono. It adds `app.defaults` (the Bun server export), `app.sse()` for server-sent events, and `Hype.router()` for sub-routers. Everything else is standard Hono.

```tsx
import { Hype } from '@because/hype'
const app = new Hype()

app.get('/', c => c.html(<h1>Hello</h1>))
app.get('/ok', c => c.text('ok'))  // Health check -- required

export default app.defaults
```

Constructor options: `prettyHTML` (default true, tools should set false), `layout` (default true), `logging` (default true).

**SSE** -- the one non-Hono addition:
```tsx
app.sse('/stream', (send, c) => {
  send({ hello: 'world' })
  const interval = setInterval(() => send({ time: Date.now() }), 1000)
  return () => clearInterval(interval)  // cleanup on disconnect
})
```

**Sub-routers:**
```tsx
const api = Hype.router()
api.get('/items', c => c.json([]))
app.route('/api', api)  // mounts at /api/items
```

## Forge

Forge creates styled JSX components via `define()`. Properties use camelCase CSS. Numbers auto-convert to `px` (except `flex`, `opacity`, `zIndex`, `fontWeight`).

```tsx
import { define, stylesToCSS } from '@because/forge'

const Box = define('Box', {
  padding: 20,
  borderRadius: '6px',
})
// <Box>content</Box> renders <div class="Box">content</div>
```

**`base`** -- set the HTML element (default `div`):
```tsx
const Button = define('Button', { base: 'button', padding: '8px 16px' })
const Link = define('Link', { base: 'a', textDecoration: 'none' })
```

**`states`** -- pseudo-classes:
```tsx
const Item = define('Item', {
  padding: 12,
  states: {
    ':hover': { backgroundColor: '#eee' },
    ':last-child': { borderBottom: 'none' },
  },
})
```

**`selectors`** -- nested CSS (`&` = the component):
```tsx
const List = define('List', {
  selectors: {
    '& > li:last-child': { borderBottom: 'none' },
  },
})
```

**`variants`** -- conditional styles via props:
```tsx
const Button = define('Button', {
  base: 'button',
  variants: {
    variant: {
      primary: { backgroundColor: '#2563eb', color: 'white' },
      danger: { backgroundColor: '#dc2626', color: 'white' },
    },
  },
})
// <Button variant="primary">Save</Button>
```

**Serving CSS** -- apps serve `stylesToCSS()` from a route. Tools prepend `baseStyles`:
```tsx
app.get('/styles.css', c =>
  c.text(baseStyles + stylesToCSS(), 200, { 'Content-Type': 'text/css; charset=utf-8' })
)
```

## Theme Tokens

Tools import `theme` from `@because/toes/tools`. It returns CSS variables that resolve per light/dark mode.

```tsx
import { baseStyles, ToolScript, theme } from '@because/toes/tools'

const Container = define('Container', {
  color: theme('colors-text'),
  border: `1px solid ${theme('colors-border')}`,
})
```

Available tokens:

| Token | Use for |
|-------|---------|
| `colors-bg`, `colors-bgSubtle`, `colors-bgElement`, `colors-bgHover` | Backgrounds |
| `colors-text`, `colors-textMuted`, `colors-textFaint` | Text |
| `colors-border` | Borders |
| `colors-link` | Links |
| `colors-primary`, `colors-primaryText` | Primary actions |
| `colors-error`, `colors-dangerBorder`, `colors-dangerText` | Errors/danger |
| `colors-success`, `colors-successBg` | Success states |
| `colors-statusRunning`, `colors-statusStopped` | Status indicators |
| `fonts-sans`, `fonts-mono` | Font stacks |
| `spacing-xs` (4), `spacing-sm` (8), `spacing-md` (12), `spacing-lg` (16), `spacing-xl` (24) | Spacing (px) |
| `radius-md` (6px) | Border radius |

## Writing a Tool

Tools need three extra things vs apps:

1. `<ToolScript />` in `<body>` (handles dark mode + iframe height communication)
2. `baseStyles` prepended to CSS output
3. Handle the `?app=` query param

```tsx
import { Hype } from '@because/hype'
import { define, stylesToCSS } from '@because/forge'
import { baseStyles, ToolScript, theme } from '@because/toes/tools'
import type { Child } from 'hono/jsx'

const APPS_DIR = process.env.APPS_DIR!
const app = new Hype({ prettyHTML: false })

const Container = define('Container', {
  fontFamily: theme('fonts-sans'),
  padding: '20px',
  paddingTop: 0,
  maxWidth: '800px',
  margin: '0 auto',
  color: theme('colors-text'),
})

function Layout({ title, children }: { title: string; children: Child }) {
  return (
    <html>
      <head>
        <meta charset="UTF-8" />
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
        <title>{title}</title>
        <link rel="stylesheet" href="/styles.css" />
      </head>
      <body>
        <ToolScript />
        <Container>{children}</Container>
      </body>
    </html>
  )
}

app.get('/ok', c => c.text('ok'))
app.get('/styles.css', c =>
  c.text(baseStyles + stylesToCSS(), 200, { 'Content-Type': 'text/css; charset=utf-8' })
)

app.get('/', async c => {
  const appName = c.req.query('app')
  if (!appName) return c.html(<Layout title="My Tool"><p>No app selected</p></Layout>)
  // ... tool logic using join(APPS_DIR, appName, 'current') for file paths
  return c.html(<Layout title="My Tool">...</Layout>)
})

export default app.defaults
```

**Environment variables** available to tools: `APPS_DIR`, `TOES_URL` (base URL of Toes server), `PORT`, `TOES_DIR`.

**Accessing app files:** always use `join(APPS_DIR, appName, 'current')`.

**Calling the Toes API:** `fetch(\`${TOES_URL}/api/apps\`)`, `fetch(\`${TOES_URL}/api/apps/${name}\`)`.

**Linking between tools:** `<a href={\`${TOES_URL}/tool/code?app=${appName}\`}>View Code</a>`.

## Patterns

**Fire-and-forget with polling** -- for long-running ops, don't await in POST. Use `<meta http-equiv="refresh" content="2" />` to poll while running.

**Inline client JS** -- use `<script dangerouslySetInnerHTML={{ __html: script }} />`.

**Data persistence** -- use filesystem. `DATA_DIR` env var points to a per-app data directory.

## Cron Jobs

Place `.ts` files in an app's `cron/` directory:

```ts
export const schedule = "day"
export default async function() {
  console.log("Running at", new Date().toISOString())
}
```

Valid schedules: `"1 minute"`, `"5 minutes"`, `"15 minutes"`, `"30 minutes"`, `"hour"`, `"noon"`, `"midnight"`, `"day"`, `"week"`, `"sunday"` through `"saturday"`.

## Coding Guidelines

TS file organization order: imports, re-exports, const/lets, enums, interfaces, types, classes, functions, module init. Within each section, exports first (alphabetical), then non-exports (alphabetical).

Single-line functions: `const fn = () => {}`. Multi-line: `function name() {}`.
