nebster

1import { atom, read, update } from 'claude-code'
2import type { EngineInterface, Register } from 'claude-code'
3
4import type { Info } from '../types'
5
6const name = atom({ plugin: 'nebster', key: 'name' } as const, null)
7const info = atom({ plugin: 'nebster', key: 'info' } as const, {
8  model: null,
9  effort: null,
10  style: null,
11  percent: null,
12  fiveHour: null,
13  weekly: null,
14} as Info)
15
16// The latest `/rename` lives in the transcript as a `custom-title` row.
17export const lastTitle = (transcript: string): string | null => {
18  const lines = transcript.split('\n')
19  for (let i = lines.length - 1; i >= 0; i--) {
20    const line = lines[i]
21    if (!line?.includes('"custom-title"')) continue
22    try {
23      const row = JSON.parse(line) as { type?: string; customTitle?: string }
24      if (row.type === 'custom-title' && row.customTitle) return row.customTitle
25    } catch {}
26  }
27  return null
28}
29
30// `claude-opus-5-5[1m]` → `Opus 5.5`; anything else passes through.
31export const prettyModel = (id: string): string => {
32  const match = /^claude-([a-z]+)-(\d+)(?:-(\d{1,2}))?(?:-\d{8})?/.exec(id)
33  if (!match) return id
34  const [, family = '', major, minor] = match
35  const label = family.charAt(0).toUpperCase() + family.slice(1)
36  return `${label} ${major}${minor ? `.${minor}` : ''}`
37}
38
39// Green, then yellow from 60%, red from 85%.
40export const usageColor = (percent: number): 'green' | 'yellow' | 'red' =>
41  percent >= 85 ? 'red' : percent >= 60 ? 'yellow' : 'green'
42
43// A rate-limit window's use, rounded; null when the account reports none.
44export const windowPercent = (
45  rateLimits: readonly { kind: string; percentUsed: number }[],
46  kind: 'five_hour' | 'seven_day',
47): number | null => {
48  const window = rateLimits.find(limit => limit.kind === kind)
49  return window === undefined ? null : Math.round(window.percentUsed)
50}
51
52async function refresh($: EngineInterface) {
53  const config =
54    (await $.env.get('CLAUDE_CONFIG_DIR')) ??
55    `${(await $.env.get('USERPROFILE')) ?? (await $.env.get('HOME'))}/.claude`
56  const project = (await $.session.root()).replace(/[^a-zA-Z0-9]/g, '-')
57  const path = `${config}/projects/${project}/${await $.session.id()}.jsonl`
58  const title = lastTitle(await $.fs.read(path).catch(() => ''))
59  if (title !== null) await update($, name, () => title)
60
61  const { context, rateLimits } = await $.session.usage()
62  const model = prettyModel(await $.session.model())
63  await update($, info, current => ({
64    ...current,
65    model: current.model ?? model,
66    percent: context.percent ?? current.percent,
67    fiveHour: windowPercent(rateLimits, 'five_hour') ?? current.fiveHour,
68    weekly: windowPercent(rateLimits, 'seven_day') ?? current.weekly,
69  }))
70}
71
72// Before the first turn, effort and output style come from settings.
73async function seed($: EngineInterface) {
74  const settings = await $.settings.read()
75  const effort = typeof settings.effortLevel === 'string' ? settings.effortLevel : null
76  const style = typeof settings.outputStyle === 'string' ? settings.outputStyle : null
77  await update($, info, current => ({
78    ...current,
79    effort: current.effort ?? effort,
80    style: current.style ?? style,
81  }))
82}
83
84export const register: Register = on => {
85  on('session.start', async ($, e, next) => {
86    const result = await next(e)
87    await seed($).catch(() => {})
88    await refresh($).catch(() => {})
89    return result
90  })
91
92  on('session.append', { door: 'command' }, async ($, e, next) => {
93    const result = await next(e)
94    await refresh($).catch(() => {})
95    return result
96  })
97
98  on('turn.complete', async ($, e, next) => {
99    const result = await next(e)
100    await refresh($).catch(() => {})
101    return result
102  })
103
104  // Rate-limit windows move between turns too; the engine pushes each whole-point move.
105  on('session.measure', async ($, e, next) => {
106    if (e.changed.includes('rateLimits')) {
107      const fiveHour = windowPercent(e.rateLimits, 'five_hour')
108      const weekly = windowPercent(e.rateLimits, 'seven_day')
109      await update($, info, current => ({
110        ...current,
111        fiveHour: fiveHour ?? current.fiveHour,
112        weekly: weekly ?? current.weekly,
113      })).catch(() => {})
114    }
115    return next(e)
116  })
117
118  // Each main-loop request carries the model and effort it actually used.
119  on('turn.step', async function* ($, e, next) {
120    if (e.agentId === undefined) {
121      const model = prettyModel(e.model)
122      const effort = e.effort === undefined ? null : String(e.effort)
123      await update($, info, current => ({ ...current, model, effort })).catch(() => {})
124    }
125    return yield* next(e)
126  })
127
128  // Subagent prompts carry no style, so only a named one counts.
129  on('prompt.compose', async ($, e, next) => {
130    if (e.outputStyle !== null) {
131      const style = e.outputStyle.name
132      await update($, info, current => ({ ...current, style })).catch(() => {})
133    }
134    return next(e)
135  })
136
137  on('ui.render', { component: 'AbovePrompt' }, async ($, e, next) => {
138    const current = await read($, name)
139    const { model, effort, style, percent, fiveHour, weekly } = await read($, info)
140    if (e.props.hasSurvey) return next(e)
141
142    const { Box, Text } = $.ui.resolve(e)
143    const details = [model, effort, style].filter(Boolean).join(' · ')
144
145    // A dim rule across the band's full width sets it apart from the chat.
146    return (
147      <Box flexDirection="column">
148        <Text dimColor>{'─'.repeat(Math.max(e.props.bodyColumns, 0))}</Text>
149        <Box>
150          {current !== null && (
151            <Text bold color="cyan">
152              {'> '}{current}
153            </Text>
154          )}
155          {details !== '' && <Text dimColor>{`${current !== null ? '  ' : ''}${details}`}</Text>}
156          {percent !== null && <Text color={usageColor(percent)}>{`  ${percent}% ctx`}</Text>}
157          {fiveHour !== null && <Text color={usageColor(fiveHour)}>{`  ${fiveHour}% 5h`}</Text>}
158          {weekly !== null && <Text color={usageColor(weekly)}>{`  ${weekly}% 7d`}</Text>}
159        </Box>
160      </Box>
161    )
162  })
163}
164

1export type Info = {
2  model: string | null
3  effort: string | null
4  style: string | null
5  percent: number | null
6  fiveHour: number | null
7  weekly: number | null
8}
9
10declare module 'claude-code' {
11  interface PluginState {
12    nebster: { name: string | null; info: Info }
13  }
14}
15