usage-pace

1import type { Hook, Register } from 'claude-code'
2import { weeklyStatus } from './pace'
3
4type Api = Parameters<Hook<'session.start'>>[0]
5
6async function show($: Api): Promise<void> {
7  const surfaces = await $.session.surfaces()
8  if (!surfaces.some(s => s !== 'terminal')) {
9    $.ui.status(undefined)
10    return
11  }
12  const { rateLimits } = await $.session.usage()
13  const week = rateLimits.find(r => r.kind === 'seven_day')
14  const text = week && weeklyStatus(week.percentUsed, week.resetsAt, await $.clock.now())
15  $.ui.status(text)
16}
17
18async function showOrClear($: Api): Promise<void> {
19  try {
20    await show($)
21  } catch (cause) {
22    $.ui.status(undefined)
23    throw new Error('usage-pace: could not read weekly usage', { cause })
24  }
25}
26
27export const register: Register = on => {
28  let timer: { cancel: () => void } | undefined
29
30  on('session.start', async ($, e, next) => {
31    const result = await next(e)
32    if (e.isInteractive === false) return result
33    timer?.cancel()
34    timer = $.clock.every(60_000, () => {
35      show($).catch(() => $.ui.status(undefined))
36    })
37    await showOrClear($)
38    return result
39  })
40
41  on('session.measure', async ($, e, next) => {
42    const result = await next(e)
43    if (e.changed.includes('rateLimits')) await showOrClear($)
44    return result
45  })
46
47  on('session.attach', async ($, e, next) => {
48    const result = await next(e)
49    await showOrClear($)
50    return result
51  })
52
53  on('session.detach', async ($, e, next) => {
54    const result = await next(e)
55    await showOrClear($)
56    return result
57  })
58}
59

1const DAY = 86_400_000
2const MIN_ELAPSED = 12 * 3_600_000
3const WEEKDAYS = ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat']
4
5export function formatTime(ms: number): string {
6  const d = new Date(ms)
7  const h = d.getHours()
8  const mm = String(d.getMinutes()).padStart(2, '0')
9  return `${WEEKDAYS[d.getDay()]} ${h % 12 || 12}:${mm} ${h < 12 ? 'AM' : 'PM'}`
10}
11
12export function weeklyStatus(used: number, resetsAt: string | undefined, now: number): string | undefined {
13  const resetMs = resetsAt === undefined ? Number.NaN : Date.parse(resetsAt)
14  if (Number.isNaN(resetMs) || resetMs <= now) return undefined
15
16  const head = `Week ${Math.round(used)}%`
17  const resets = `${head} · resets ${formatTime(resetMs)}`
18  const start = resetMs - 7 * DAY
19  const elapsed = now - start
20  if (used >= 100 || used === 0 || elapsed < MIN_ELAPSED) return resets
21
22  const perDay = Math.round((100 - used) / ((resetMs - now) / DAY))
23  const outAt = start + (elapsed * 100) / used
24  return outAt >= resetMs
25    ? `${head} · lasts to ${formatTime(resetMs)} · ${perDay}%/day left`
26    : `${head} · out ~${formatTime(outAt)} · ${perDay}%/day left`
27}
28