git-status-band

1import { atom, read, update } from 'claude-code'
2import type { EngineInterface, Register } from 'claude-code'
3
4import type { GitSummary } from '../types'
5
6const summary = atom({ plugin: 'git-status-band', key: 'summary' } as const, null)
7const isHidden = atom({ plugin: 'git-status-band', key: 'isHidden' } as const, false)
8
9const REFRESH_MS = 15000
10
11// Turns `git status --porcelain=v1 -b` output into a small summary.
12// First line looks like: "## main...origin/main [ahead 1, behind 2]"
13function parse(stdout: string): GitSummary {
14  const lines = stdout.split('\n').filter(line => line.length > 0)
15  const head = lines[0] ?? ''
16  const changed = lines.length - 1
17
18  const branch = head.replace(/^## /, '').split('...')[0].replace(/^No commits yet on /, '')
19  const hasUpstream = head.includes('...')
20  const ahead = Number(/ahead (\d+)/.exec(head)?.[1] ?? 0)
21  const behind = Number(/behind (\d+)/.exec(head)?.[1] ?? 0)
22
23  let kind: GitSummary['kind'] = 'synced'
24  if (changed > 0) kind = 'dirty'
25  else if (ahead > 0 && behind > 0) kind = 'diverged'
26  else if (ahead > 0) kind = 'ahead'
27  else if (behind > 0) kind = 'behind'
28  else if (!hasUpstream) kind = 'no-upstream'
29
30  return { kind, branch, changed, ahead, behind }
31}
32
33function plural(n: number, one: string, many: string) {
34  return `${n} ${n === 1 ? one : many}`
35}
36
37// The sentence the user sees: plain language, no git jargon.
38function describe(s: GitSummary): { icon: string; color: string; text: string } {
39  switch (s.kind) {
40    case 'dirty':
41      return {
42        icon: '●',
43        color: 'warning',
44        text: `${plural(s.changed, 'file has', 'files have')} changes that are not saved yet. Say /save when you are done.`,
45      }
46    case 'ahead':
47      return {
48        icon: '↑',
49        color: 'warning',
50        text: `Saved on this computer, but ${plural(s.ahead, 'update is', 'updates are')} not on GitHub yet. /save sends them.`,
51      }
52    case 'behind':
53      return {
54        icon: '↓',
55        color: 'warning',
56        text: `GitHub has ${plural(s.behind, 'newer update', 'newer updates')} from the other account. Say /start to get them.`,
57      }
58    case 'diverged':
59      return {
60        icon: '⇅',
61        color: 'error',
62        text: 'This computer and GitHub both have new work. Ask Claude to sort it out before continuing.',
63      }
64    case 'no-upstream':
65      return { icon: '○', color: 'warning', text: 'This work is not connected to GitHub yet.' }
66    default:
67      return { icon: '✓', color: 'success', text: 'Everything is saved and matches GitHub.' }
68  }
69}
70
71let lastKey = ''
72let isRunning = false
73
74async function refresh($: EngineInterface) {
75  if (isRunning) return
76  isRunning = true
77  try {
78    const { exitCode, stdout } = await $.process.run(['git', 'status', '--porcelain=v1', '-b'], {
79      timeoutMs: 10000,
80    })
81    const next = exitCode === 0 ? parse(stdout) : null
82    const key = JSON.stringify(next)
83    if (key !== lastKey) {
84      lastKey = key
85      await update($, summary, () => next)
86    }
87  } catch {
88    // git missing or not a repo: show nothing
89    if (lastKey !== 'null') {
90      lastKey = 'null'
91      await update($, summary, () => null)
92    }
93  } finally {
94    isRunning = false
95  }
96}
97
98export const register: Register = on => {
99  on('session.start', async ($, e, next) => {
100    void refresh($)
101    $.clock.every(REFRESH_MS, () => refresh($))
102    return next(e)
103  })
104
105  on('turn.complete', async ($, e, next) => {
106    void refresh($)
107    return next(e)
108  })
109
110  on('ui.render', { component: 'AbovePrompt' }, async ($, e, next) => {
111    const s = await read($, summary)
112    if (e.props.hasSurvey || s === null || (await read($, isHidden))) {
113      return next(e)
114    }
115
116    const { Box, Button, Text } = $.ui.resolve(e)
117    const { icon, color, text } = describe(s)
118
119    return (
120      <Box flexDirection="row" columnGap={1}>
121        <Text color={color}>{icon}</Text>
122        <Text dimColor>{text}</Text>
123        <Button key="refresh" label="Refresh" onPress={() => refresh($)} />
124        <Button key="hide" label="Hide" onPress={() => update($, isHidden, () => true)} />
125      </Box>
126    )
127  })
128}
129

1export type GitSummary = {
2  kind: 'none' | 'synced' | 'dirty' | 'ahead' | 'behind' | 'diverged' | 'no-upstream'
3  branch: string
4  changed: number
5  ahead: number
6  behind: number
7}
8
9declare module 'claude-code' {
10  interface PluginState {
11    'git-status-band': { summary: GitSummary | null; isHidden: boolean }
12  }
13}
14