play with LEDs

src/server/audio.ts

@@ -1,5 +1,6 @@
 import factory from 'ggwave'
 import { getAudioSetup } from './audio-setup'
+import { setRgbLedState } from './rgbled'
 
 export const SAMPLE_RATE = 48000
 
@@ -155,28 +156,35 @@ export async function loopbackTest(): Promise<LoopbackTestResult> {
 
 export async function playAudio(text: string) {
   playing = true
+  setRgbLedState('chirping')
 
-  const waveform = ggwave.encode(
-    instance, text,
-    ggwave.ProtocolId.GGWAVE_PROTOCOL_AUDIBLE_FAST,
-    50
-  )
-  const rawBytes = new Uint8Array(waveform.length)
-  rawBytes.set(new Uint8Array(waveform.buffer, waveform.byteOffset, waveform.length))
+  try {
+    const waveform = ggwave.encode(
+      instance, text,
+      ggwave.ProtocolId.GGWAVE_PROTOCOL_AUDIBLE_FAST,
+      50
+    )
+    const rawBytes = new Uint8Array(waveform.length)
+    rawBytes.set(new Uint8Array(waveform.buffer, waveform.byteOffset, waveform.length))
 
-  const play = createPlaybackProcess()
-  const errorPromise = getText(play.stderr)
-  play.stdin.write(rawBytes)
-  play.stdin.end()
-  await play.exited
+    const play = createPlaybackProcess()
+    const errorPromise = getText(play.stderr)
+    play.stdin.write(rawBytes)
+    play.stdin.end()
+    await play.exited
 
-  logProcessError('Playback error', await errorPromise)
+    logProcessError('Playback error', await errorPromise)
 
-  await new Promise(r => setTimeout(r, 300))
-  playing = false
+    await new Promise(r => setTimeout(r, 300))
+  } finally {
+    playing = false
+    setRgbLedState('listening')
+  }
 }
 
 export function startMicListener(onMessage: (text: string) => void) {
+  setRgbLedState('listening')
+
   const sox = createRecordingProcess()
   const errorPromise = getText(sox.stderr)
   const reader = sox.stdout.getReader()

src/server/rgbled.ts

@@ -0,0 +1,165 @@
+import { existsSync } from 'node:fs'
+
+const LED_PATTERNS: Record<Exclude<RgbLedState, 'off'>, RgbLedPattern> = {
+  chirping: {
+    colors: ['331400', 'ff5500', 'ffcc00', 'ff5500', '331400'],
+    duration: '90ms',
+    repeat: true,
+  },
+  correct: {
+    colors: ['002200', '22cc55', 'ffdd55', '22cc55', '002200'],
+    duration: '140ms',
+    restoreState: 'listening',
+  },
+  error: {
+    colors: ['220000', 'ff0033', '220000', '220000', 'ff0033', '220000'],
+    duration: '120ms',
+    repeat: true,
+  },
+  listening: {
+    colors: ['001833', '0066ff', '33ccff', '0066ff', '001833'],
+    duration: '500ms',
+    repeat: true,
+  },
+  startup: {
+    colors: ['220022', 'ff00aa', 'ff8800', 'ffcc00', '00cc88', '3399ff'],
+    duration: '140ms',
+    repeat: true,
+  },
+}
+const RGBLED_BIN = process.env.BAUDY_RGBLED_BIN?.trim() || 'rgbled'
+const RGBLED_ORDER = process.env.BAUDY_RGBLED_ORDER?.trim() || 'brg'
+const SPI_DEVICE = '/dev/spidev0.0'
+
+let activeProcess: SpawnedProcess | undefined
+let available: boolean | undefined
+let currentState: RgbLedState | undefined
+let stateVersion = 0
+
+interface RgbLedPattern {
+  colors: string[]
+  duration: string
+  repeat?: boolean
+  restoreState?: RgbLedState
+}
+
+export type RgbLedState = 'chirping' | 'correct' | 'error' | 'listening' | 'off' | 'startup'
+
+type SpawnedProcess = ReturnType<typeof Bun.spawn>
+
+export function getRgbLedStatus() {
+  if (!isRgbLedAvailable()) return
+  return `${RGBLED_BIN} (order ${RGBLED_ORDER}, animated)`
+}
+
+export function isRgbLedAvailable() {
+  if (available !== undefined) return available
+  if (process.platform !== 'linux') return available = false
+  if (process.env.BAUDY_RGBLED?.trim() === '0') return available = false
+  if (!existsSync(SPI_DEVICE)) return available = false
+  if (!commandExists(RGBLED_BIN)) return available = false
+
+  const probe = Bun.spawnSync([RGBLED_BIN, '--order', RGBLED_ORDER, 'off'], {
+    stdout: 'ignore',
+    stderr: 'ignore',
+  })
+
+  available = probe.exitCode === 0
+  return available
+}
+
+export function setRgbLedState(state: RgbLedState) {
+  if (!isRgbLedAvailable()) return false
+
+  currentState = state
+  stateVersion++
+  stopActiveProcess()
+
+  if (state === 'off') return runRgbLedSync(['off'])
+
+  const pattern = LED_PATTERNS[state]
+  const process = spawnPattern(pattern)
+  if (!process) return false
+
+  activeProcess = process
+  void trackPatternExit(process, pattern, state, stateVersion)
+  return true
+}
+
+function buildPatternArgs(pattern: RgbLedPattern) {
+  const args = [RGBLED_BIN, '--order', RGBLED_ORDER, 'lerp', ...pattern.colors, '--duration', pattern.duration]
+
+  if (pattern.repeat) args.push('--loop', 'true')
+
+  return args
+}
+
+function commandExists(command: string) {
+  if (command.includes('/')) return existsSync(command)
+
+  const proc = Bun.spawnSync(['which', command], {
+    stdout: 'ignore',
+    stderr: 'ignore',
+  })
+
+  return proc.exitCode === 0
+}
+
+function getText(stream: ReadableStream<Uint8Array> | null | undefined) {
+  if (!stream) return Promise.resolve('')
+  return new Response(stream).text().catch(() => '')
+}
+
+function runRgbLedSync(args: string[]) {
+  const proc = Bun.spawnSync([RGBLED_BIN, '--order', RGBLED_ORDER, ...args], {
+    stdout: 'ignore',
+    stderr: 'ignore',
+  })
+
+  if (proc.exitCode === 0) return true
+
+  available = false
+  return false
+}
+
+function spawnPattern(pattern: RgbLedPattern) {
+  try {
+    return Bun.spawn(buildPatternArgs(pattern), {
+      stdin: 'ignore',
+      stdout: 'ignore',
+      stderr: 'pipe',
+    })
+  } catch {
+    available = false
+    return
+  }
+}
+
+function stopActiveProcess() {
+  if (!activeProcess) return
+
+  try {
+    activeProcess.kill()
+  } catch {
+    // ignored
+  }
+
+  activeProcess = undefined
+}
+
+async function trackPatternExit(process: SpawnedProcess, pattern: RgbLedPattern, state: RgbLedState, version: number) {
+  const errorPromise = getText(process.stderr)
+  const exitCode = await process.exited
+  const error = (await errorPromise).trim()
+
+  if (activeProcess === process) activeProcess = undefined
+  if (version !== stateVersion || currentState !== state) return
+
+  if (exitCode !== 0) {
+    available = false
+    if (error) console.error(`RGB LED error: ${error.split('\n')[0]}`)
+    return
+  }
+
+  if (pattern.restoreState) setRgbLedState(pattern.restoreState)
+}

src/server/terminal.ts

@@ -3,6 +3,7 @@ import { loopbackTest, playAudio, startMicListener } from './audio'
 import { getSecret, handleGuess } from './game'
 import type { GuessResult } from './game'
 import { getLocalServerUrls, isLocalTlsEnabled } from './local-tls'
+import { getRgbLedStatus, setRgbLedState } from './rgbled'
 import pkg from '../../package.json'
 
 const RESET = '\x1b[0m'
@@ -184,16 +185,21 @@ async function onMessage(text: string) {
   }
 
   const result = await handleGuess(text)
-  if (result) logGuess(result)
+  if (!result) return
+
+  if (result.type === 'correct') setRgbLedState('correct')
+  logGuess(result)
 }
 
 export async function startup(port: number) {
   if (!commandExists('sox')) {
+    setRgbLedState('error')
     console.error(`\n  ${BOLD}sox is not installed.${RESET} Run: ${getSoxInstallCommand()}\n`)
     process.exit(1)
   }
 
   let audioSetup = getAudioSetup()
+  const rgbLedStatus = getRgbLedStatus()
 
   clearScreen()
   console.log()
@@ -201,6 +207,10 @@ export async function startup(port: number) {
   console.log()
   console.log(`${BOLD}Speaker:${RESET}    ${GREEN}${audioSetup.playbackLabel}${RESET}`)
   console.log(`${BOLD}Microphone:${RESET} ${GREEN}${audioSetup.captureLabel}${RESET}`)
+  if (process.platform === 'linux') {
+    const ledValue = rgbLedStatus ? `${GREEN}${rgbLedStatus}${RESET}` : `${DIM}not available${RESET}`
+    console.log(`${BOLD}RGB LED:${RESET}    ${ledValue}`)
+  }
   console.log()
 
   if (process.platform === 'linux' && isLowMixerLevel(audioSetup.mixerLevel)) {
@@ -216,11 +226,13 @@ export async function startup(port: number) {
   console.log(`${DIM}Testing audio: playing a chirp and listening for it...${RESET}`)
   console.log()
 
+  setRgbLedState('startup')
   const loopback = await loopbackTest()
 
   if (loopback.ok) {
     console.log(`${GREEN}${BOLD}✓ Audio working!${RESET} ${DIM}Speaker → mic pipeline verified${RESET}`)
   } else {
+    setRgbLedState('error')
     logLoopbackFailureDetails(loopback)
     await maybePause('  Press Enter to continue anyway... ')
   }
@@ -277,5 +289,6 @@ export async function startup(port: number) {
   console.log(`${DIM}🎤 Listening for guesses...${RESET}`)
   console.log()
 
+  setRgbLedState('listening')
   startMicListener(onMessage)
 }