paste-inline

1import type { EngineInterface, Register } from 'claude-code'
2
3import {
4  CLIPBOARD_CANDIDATES,
5  clipboardMatches,
6  expand,
7  findTags,
8  splitCommand,
9  tooLong,
10} from './paste'
11
12const POLL_MS = 250
13
14async function readClipboard(
15  $: EngineInterface,
16  argv: readonly string[],
17): Promise<string | undefined> {
18  const r = await $.process.run(argv, { timeoutMs: 2000 }).catch(() => undefined)
19  return r !== undefined && r.exitCode === 0 ? r.stdout : undefined
20}
21
22async function findClipboard(
23  $: EngineInterface,
24  custom: string[],
25): Promise<readonly string[] | undefined> {
26  const list = custom.length > 0 ? [custom] : CLIPBOARD_CANDIDATES
27  for (const argv of list) {
28    if ((await readClipboard($, argv)) !== undefined) return argv
29  }
30  return undefined
31}
32
33export const register: Register = (on, options) => {
34  const custom = splitCommand(options?.clipboardCommand)
35  const maxLines = typeof options?.maxLines === 'number' ? options.maxLines : 0
36  const seen = new Set<number>() // tag numbers already tried: never retry a mismatch
37  let argv: readonly string[] | undefined
38  let isOn = true
39  let isBusy = false
40
41  on('session.start', async ($, e, next) => {
42    await $.command.register({
43      name: 'paste-inline',
44      description: 'Turn inline paste expansion on or off (/paste-inline on|off)',
45    })
46
47    $.clock.every(POLL_MS, async () => {
48      if (!isOn || isBusy) return
49      isBusy = true
50      try {
51        const box = await $.prompt.read()
52        const fresh = findTags(box.text).filter(t => !seen.has(t.id))
53        if (fresh.length === 0) return
54        argv = argv ?? (await findClipboard($, custom))
55        if (argv === undefined) {
56          for (const t of fresh) seen.add(t.id)
57          return
58        }
59        // Only the newest tag can be what the clipboard holds now.
60        const tag = fresh[fresh.length - 1]
61        for (const t of fresh) seen.add(t.id)
62        const clip = await readClipboard($, argv)
63        if (clip === undefined || !clipboardMatches(tag, clip) || tooLong(clip, maxLines)) return
64        const now = await $.prompt.read()
65        if (!now.text.includes(tag.raw)) return
66        await $.prompt.fill({ text: expand(now.text, tag, clip), mode: 'replace' })
67      } finally {
68        isBusy = false
69      }
70    })
71
72    return next(e)
73  })
74
75  on('command.run', { command: 'paste-inline' }, async (_$, e) => {
76    const arg = e.args.trim().toLowerCase()
77    if (arg === 'off') isOn = false
78    else if (arg === 'on') isOn = true
79    else isOn = !isOn
80    return { text: `paste-inline is ${isOn ? 'on' : 'off'}.` }
81  })
82}
83

1// Pure helpers for finding Claude Code's paste tags and matching them to the clipboard.
2
3export type Tag = { raw: string; id: number; lines: number }
4
5const TAG = /\[Pasted text #(\d+)(?: \+(\d+) lines)?\]/g
6
7export function findTags(draft: string): Tag[] {
8  const out: Tag[] = []
9  for (const m of draft.matchAll(TAG)) {
10    out.push({ raw: m[0], id: Number(m[1]), lines: m[2] === undefined ? 0 : Number(m[2]) })
11  }
12  return out
13}
14
15const newlines = (s: string): number => (s.match(/\n/g) ?? []).length
16
17/** Strips what clipboard tools add: CRLF and one trailing newline. */
18export function normalize(clip: string): string {
19  return clip.replace(/\r\n/g, '\n').replace(/\n$/, '')
20}
21
22/**
23 * The tag counts the pasted text's lines; clipboards differ by a trailing newline,
24 * so a difference of one is tolerated. An empty clipboard never matches.
25 */
26export function clipboardMatches(tag: Tag, clip: string): boolean {
27  const text = normalize(clip)
28  if (text.trim() === '') return false
29  const n = newlines(text)
30  return Math.abs(n - tag.lines) <= 1
31}
32
33export function tooLong(clip: string, maxLines: number): boolean {
34  return maxLines > 0 && newlines(normalize(clip)) + 1 > maxLines
35}
36
37export function expand(draft: string, tag: Tag, clip: string): string {
38  const at = draft.indexOf(tag.raw)
39  if (at < 0) return draft
40  return draft.slice(0, at) + normalize(clip) + draft.slice(at + tag.raw.length)
41}
42
43export function splitCommand(s: unknown): string[] {
44  return typeof s === 'string' ? s.split(/\s+/).filter(x => x !== '') : []
45}
46
47export const CLIPBOARD_CANDIDATES: readonly string[][] = [
48  ['pbpaste'],
49  ['wl-paste', '--no-newline'],
50  ['xclip', '-selection', 'clipboard', '-o'],
51  ['xsel', '--clipboard', '--output'],
52  ['powershell.exe', '-NoProfile', '-Command', 'Get-Clipboard -Raw'],
53]
54