lofi

1import type { EngineInterface, Register } from 'claude-code'
2
3// lofi: a soundtrack that follows the session.
4//   calm  while Claude is idle (then silence after a few minutes)
5//   focus while a turn runs
6//   flow  when Claude is editing hard (3+ edits inside a minute)
7//   cues: a chime when a test command passes, a low note when it fails,
8//         a soft chord when a long turn finishes.
9// Off until /lofi on. Every sound is the mod's own file (audio/, synthesised
10// by scripts/make_audio.py), played through the system player.
11
12type Mood = 'calm' | 'focus' | 'flow'
13type Cue = 'pass' | 'fail' | 'done'
14
15const EDIT_TOOLS = new Set(['Edit', 'Write', 'MultiEdit', 'NotebookEdit'])
16const TEST_COMMAND = /\b(pytest|jest|vitest|mocha|go test|cargo test|npm (run )?test|pnpm (run )?test|yarn test|bun test|claude plugin test|unittest|rspec|phpunit)\b/
17const FLOW_EDITS = 3
18const FLOW_WINDOW_MS = 60_000
19const LONG_TURN_MS = 45_000
20const OVERLAP_MS = 250 // the old loop keeps playing this long under the new one
21
22// Module state: a hot reload starts the music over.
23let enabled = false
24let volume = 30
25let mood: Mood | null = null
26let loop: AbortController | null = null
27let idleTimer: { cancel: () => void } | null = null
28let turnStartedAt = 0
29let edits: number[] = []
30
31const gain = () => Math.max(0, Math.min(100, volume)) / 100
32
33async function setMood($: EngineInterface, next: Mood | null) {
34  if (next === mood && (next === null || loop)) return
35  const old = loop
36  mood = next
37  loop = null
38  if (next) {
39    const c = new AbortController()
40    loop = c
41    $.audio.play({ asset: `audio/${next}.mp3` }, { shouldLoop: true, gain: gain(), signal: c.signal }).catch(() => {
42      if (loop === c) loop = null // the player failed: let the next mood try again
43    })
44  }
45  if (old) {
46    if (next) $.clock.after(OVERLAP_MS, () => old.abort())
47    else old.abort()
48  }
49}
50
51async function cue($: EngineInterface, name: Cue) {
52  $.audio.play({ asset: `audio/${name}.mp3` }, { gain: Math.min(1, gain() * 1.6) }).catch(() => {})
53}
54
55export const register: Register = (on, options) => {
56  const idleMs = Math.max(0, Number(options.idleMinutes ?? 3)) * 60_000
57
58  on('session.start', async ($, e, next) => {
59    const r = await next(e)
60    enabled = (await $.store.get('enabled')) === true
61    const saved = Number(await $.store.get('volume'))
62    volume = Number.isFinite(saved) && saved > 0 ? saved : Number(options.volume ?? 30)
63    await $.command.register({
64      name: 'lofi',
65      description: 'lofi: a soundtrack that follows the session (on, off, vol 0-100, status)',
66      argumentHint: '[on | off | vol <0-100> | status]',
67      immediate: true,
68    })
69    return r
70  })
71
72  on('turn.start', async ($, e, next) => {
73    if (!e.agentId) {
74      turnStartedAt = await $.clock.now()
75      idleTimer?.cancel()
76      idleTimer = null
77      if (enabled) await setMood($, 'focus')
78    }
79    return next(e)
80  })
81
82  on('tool.call', async ($, e, next) => {
83    const ran = await next(e)
84    if (!enabled || ran.deny !== undefined) return ran
85    if (EDIT_TOOLS.has(e.tool) && ran.isError !== true) {
86      const now = await $.clock.now()
87      edits = [...edits.filter(t => now - t < FLOW_WINDOW_MS), now]
88      if (edits.length >= FLOW_EDITS && mood !== 'flow') await setMood($, 'flow')
89    } else if (e.tool === 'Bash') {
90      const command = String((e as unknown as { command?: unknown }).command ?? '')
91      if (TEST_COMMAND.test(command)) await cue($, ran.isError === true ? 'fail' : 'pass')
92    }
93    return ran
94  })
95
96  on('turn.complete', async ($, e, next) => {
97    const r = await next(e)
98    if (e.agentId || !enabled) return r
99    const now = await $.clock.now()
100    if (!e.isAborted && now - turnStartedAt > LONG_TURN_MS) await cue($, 'done')
101    edits = []
102    await setMood($, 'calm')
103    idleTimer?.cancel()
104    idleTimer = $.clock.after(idleMs, () => {
105      idleTimer = null
106      void setMood($, null)
107    })
108    return r
109  })
110
111  on('command.run', { command: 'lofi' }, async ($, e) => {
112    const [word, value] = String(e.args ?? '').trim().toLowerCase().split(/\s+/)
113    if (word === 'on') {
114      enabled = true
115      await $.store.set('enabled', true)
116      await setMood($, 'calm')
117      return { text: 'lofi is on. calm now, focus while Claude works, flow when it edits hard.' }
118    }
119    if (word === 'off') {
120      enabled = false
121      await $.store.set('enabled', false)
122      idleTimer?.cancel()
123      idleTimer = null
124      await setMood($, null)
125      return { text: 'lofi is off.' }
126    }
127    if (word === 'vol') {
128      const v = Number(value)
129      if (!(v >= 0 && v <= 100)) return { text: 'Give a volume from 0 to 100, like /lofi vol 25.' }
130      volume = v
131      await $.store.set('volume', v)
132      if (mood) {
133        const playing = mood
134        await setMood($, null) // restart the loop at the new volume
135        await setMood($, playing)
136      }
137      return { text: `Volume ${v}.` }
138    }
139    if (word && word !== 'status') return { text: 'Try /lofi on, /lofi off, /lofi vol 25 or /lofi status.' }
140    return { text: enabled ? `lofi is on, volume ${volume}, playing ${mood ?? 'nothing (idle)'}.` : 'lofi is off. /lofi on starts it.' }
141  })
142}
143