screen-share

1import type { EngineInterface, Register } from 'claude-code'
2
3import { BAR, FADE, mask, maskDeep } from './mask'
4
5// Screen-Share Mode: /screen-share turns it on or off. (/share cannot be used: it
6// is the built-in /bug's other name, and the engine refuses to register it.) While on, the transcript rows
7// draw emails, phone numbers, money amounts and names as shaded bars of the
8// same length (▒▒▒▒ ▒▒▒), so lines keep their length and nothing jumps.
9// Only the drawing changes: the stored chat, and what Claude reads, stay real.
10//
11// Hover to reveal is not done: these rows are drawn by the engine from a
12// markdown string, and hover styles only apply to a Text or Box the mod draws
13// itself. Drawing our own rows would lose the engine's markdown.
14
15const ON = { plugin: 'screen-share', key: 'on' } as const
16const BAND_TEXT = ' Screen-share mode: emails, phones, amounts and names hidden on screen'
17
18// Module variables reset on a reload; the mode itself lives in $.state and $.store.
19let sid = ''
20let home = ''
21// The bar glyph rows draw with now: light for the first frame after turning
22// on, then the full bar. A fade in of one step, 150 ms.
23let glyph = BAR
24const FADE_MS = 150
25
26// The /mods switchboard turns this mod off in every chat with switches.json.
27const NAME = 'screen-share'
28let off = false
29
30async function readSwitch($: EngineInterface) {
31  let now = false
32  try {
33    const path = `${$.plugin.root.replace(/\\/g, '/').split('/.claude/')[0] ?? ''}/.claude/mods/switches.json`
34    if (await $.fs.exists(path)) {
35      const json = JSON.parse(String(await $.fs.read(path))) as Record<string, unknown>
36      now = json[NAME] === false
37    }
38  } catch {
39    now = off
40  }
41  if (now === off) return
42  off = now
43  try {
44    $.ui.invalidate('ui.render')
45  } catch {
46    // The next state change redraws anyway.
47  }
48  try {
49    // The status line follows the switch: hidden while off, back when on again.
50    const { value } = await $.state.get(ON)
51    await $.ui.status(!off && value === true ? 'Screen-share on' : undefined)
52  } catch {
53    // The status line is a nicety.
54  }
55}
56
57async function logError($: EngineInterface, where: string, err: unknown) {
58  try {
59    const path = `${home || '~'}/.claude/mods-logs/screen-share.log`
60    let old = ''
61    try {
62      old = String(await $.fs.read(path))
63    } catch {
64      // First error: no log yet.
65    }
66    const at = new Date(await $.clock.now()).toISOString()
67    const msg = err instanceof Error ? `${err.name}: ${err.message}` : String(err)
68    await $.fs.write(path, `${old}${at} ${where}: ${msg}\n`)
69  } catch {
70    // Logging must never break the screen.
71  }
72}
73
74async function isOn($: EngineInterface) {
75  if (off) return false
76  const { value } = await $.state.get(ON)
77  return value === true
78}
79
80// Every row this mod hooks is drawn again now, old messages included, instead
81// of at the next state redraw.
82function redrawAll($: EngineInterface) {
83  try {
84    $.ui.invalidate('ui.render')
85  } catch {
86    // The state write below redraws anyway, a little later.
87  }
88}
89
90async function setMode($: EngineInterface, on: boolean) {
91  glyph = on ? FADE : BAR
92  await $.state.set(ON, on)
93  redrawAll($)
94  if (on) {
95    $.clock.after(FADE_MS, () => {
96      glyph = BAR
97      redrawAll($)
98    })
99  }
100  try {
101    await $.ui.status(on ? 'Screen-share on' : undefined)
102  } catch (err) {
103    await logError($, 'ui.status', err)
104  }
105  try {
106    if (sid) await $.store.set(`on:${sid}`, on)
107  } catch (err) {
108    await logError($, 'store.set', err)
109  }
110}
111
112export const register: Register = on => {
113  on('session.start', async ($, e, next) => {
114    await $.command.register({
115      name: 'screen-share',
116      description: 'Screen-Share Mode on or off: hides emails, phone numbers, amounts and names on screen (Claude still reads the real data)',
117      argumentHint: '[on|off]',
118      // Works at once, also while Claude is busy, instead of after the turn.
119      immediate: true,
120    })
121    try {
122      sid = await $.session.id()
123      home = $.plugin.root.replace(/\\/g, '/').split('/.claude/')[0] ?? ''
124      await readSwitch($).catch(() => undefined)
125      $.clock.every(3000, () => {
126        void readSwitch($).catch(() => undefined)
127      })
128      // A reload keeps the mode this chat had.
129      const saved = await $.store.get(`on:${sid}`)
130      if (saved === true && (await $.state.get(ON)).value !== true) {
131        await $.state.set(ON, true)
132        if (!off) await $.ui.status('Screen-share on')
133      }
134    } catch (err) {
135      await logError($, 'session.start', err)
136    }
137    return next(e)
138  })
139
140  on('command.run', { command: 'screen-share' }, async ($, e) => {
141    if (off) return { text: 'Screen-Share Mode is off. Turn it on with /mods.' }
142    try {
143      const arg = String((e as { args?: string }).args ?? '').trim().toLowerCase()
144      const now = await isOn($)
145      const want = arg === 'on' ? true : arg === 'off' ? false : !now
146      await setMode($, want)
147      return {
148        text: want
149          ? 'Screen-share on. Emails, phone numbers, amounts and names show as shaded bars on screen. Claude still reads the real data. Run /screen-share again to turn it off.'
150          : 'Screen-share off. Everything shows as normal.',
151      }
152    } catch (err) {
153      await logError($, 'command.run', err)
154      return { text: 'Screen-share could not switch. See ~/.claude/mods-logs/screen-share.log.' }
155    }
156  })
157
158  on('ui.press', { plugin: 'screen-share', element: 'off' }, async ($, e) => {
159    try {
160      await setMode($, false)
161    } catch (err) {
162      await logError($, 'ui.press', err)
163    }
164    return { element: e.element }
165  })
166
167  // The transcript rows. Each hook reads the mode while drawing, so a switch
168  // redraws every row that read it. Nothing changed: the props pass as they came.
169
170  on('ui.render', { component: 'UserMessage' }, async ($, e, next) => {
171    if (!(await isOn($))) return next(e)
172    const text = mask(e.props.text, glyph)
173    return text === e.props.text ? next(e) : next({ ...e, props: { ...e.props, text } })
174  })
175
176  on('ui.render', { component: 'AssistantMessage' }, async ($, e, next) => {
177    if (!(await isOn($))) return next(e)
178    const text = mask(e.props.text, glyph)
179    return text === e.props.text ? next(e) : next({ ...e, props: { ...e.props, text } })
180  })
181
182  on('ui.render', { component: 'CommandOutput' }, async ($, e, next) => {
183    if (!(await isOn($))) return next(e)
184    const text = mask(e.props.text, glyph)
185    return text === e.props.text ? next(e) : next({ ...e, props: { ...e.props, text } })
186  })
187
188  on('ui.render', { component: 'ToolUse' }, async ($, e, next) => {
189    if (!(await isOn($))) return next(e)
190    const input = maskDeep(e.props.input, glyph)
191    const output = maskDeep(e.props.output, glyph)
192    if (input === e.props.input && output === e.props.output) return next(e)
193    return next({ ...e, props: { ...e.props, input, output } })
194  })
195
196  on('ui.render', { component: 'ToolResult' }, async ($, e, next) => {
197    if (!(await isOn($))) return next(e)
198    const output = maskDeep(e.props.output, glyph)
199    return output === e.props.output ? next(e) : next({ ...e, props: { ...e.props, output } })
200  })
201
202  // The folded group line only counts calls ("Read 3 files"); its unfolded rows
203  // are ToolUse rows, masked above. The calls are masked too, for any surface
204  // that draws a detail from them.
205  on('ui.render', { component: 'ToolGroup' }, async ($, e, next) => {
206    if (!(await isOn($))) return next(e)
207    const calls = maskDeep(e.props.calls, glyph)
208    return calls === e.props.calls ? next(e) : next({ ...e, props: { ...e.props, calls } })
209  })
210
211  on('ui.render', { component: 'AbovePrompt' }, async ($, e, next) => {
212    if (e.props.hasSurvey || !(await isOn($))) return next(e)
213    const rest = await next(e)
214    const { Box, Text, Button } = $.ui.resolve(e)
215    const noop = () => undefined
216    return (
217      <Box flexDirection="column">
218        {rest}
219        <Box flexDirection="row" alignItems="center" justifyContent="space-between" gap={1}>
220          <Box flexShrink={1}>
221            <Text wrap="truncate-end">
222              <Text color="claude">●</Text>
223              <Text dimColor>{BAND_TEXT}</Text>
224            </Text>
225          </Box>
226          <Button key="off" label="Turn off" onPress={noop} />
227        </Box>
228      </Box>
229    )
230  })
231}
232

1// The masking rules for Screen-Share Mode. Pure functions, no engine calls.
2// Conservative on purpose: a year, a version, a token count like 182k or a file
3// path must never be hidden. A miss is better than hiding plain numbers.
4//
5// Each hidden span is drawn as a shaded bar of the same length as the text it
6// hides (spaces stay spaces), so a line keeps its length and wrapping.
7
8export type Kind = 'email' | 'phone' | 'amount' | 'name'
9type Span = { a: number; b: number; kind: Kind }
10
11/** The bar a hidden span is drawn with, and the lighter one of the fade in. */
12export const BAR = '▒'
13export const FADE = '░'
14
15// Every regex is built once, here, when the module loads.
16
17// An ssh remote (git@github.com:me/repo) is not an email and stays.
18const EMAIL_SRC = String.raw`[A-Za-z0-9._%+-]+@[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]*[A-Za-z0-9])?)*\.[A-Za-z]{2,24}(?![A-Za-z0-9-])(?!:[\w~/])`
19const EMAIL_RE = new RegExp(EMAIL_SRC, 'g')
20
21// Links: phone and money hits inside one are left alone (ids, query strings).
22const URL_RE = /\b(?:https?:\/\/|www\.)[^\s<>"'`)\]]+/gi
23
24// Money. The number part: 4,500 / 4500 / 4,250.00 / 12.5
25const NUM = String.raw`\d{1,3}(?:,\d{3})+(?:\.\d+)?|\d+(?:\.\d+)?`
26const SCALE = String.raw`(?:\s?(?:k|K|m|M|bn|mn|b|B)\b|\s(?:thousand|million|billion|lakh|lakhs|crore|crores)\b)`
27const CODES = 'USD|GBP|EUR|INR|AUD|CAD|NZD|SGD|AED|JPY|CHF|HKD'
28const MONEY_RES: RegExp[] = [
29  // $1,234.56  £900  €12k  ₹4,500  US$300  -$40  \$500 (escaped in markdown)
30  new RegExp(String.raw`(?<![\w$])(?:US|AU|CA|NZ|HK|S|A|C)?\\?[$£€₹¥]\s?(?:${NUM})${SCALE}?(?![\w%])`, 'g'),
31  // USD 300  INR 4,500  Rs. 900  Rs 1.2 lakh
32  new RegExp(String.raw`(?<![\w])(?:${CODES}|Rs\.?)\s?(?:${NUM})${SCALE}?(?![\w%])`, 'g'),
33  // 1,200 dollars  300 USD  12€  5k euros
34  new RegExp(String.raw`(?<![\w.,])(?:${NUM})${SCALE}?\s?(?:${CODES}|€|dollars?|euros?|rupees?|bucks)(?![\w])`, 'g'),
35]
36const BARE_ARG_RE = /^\\?\$\d$/
37
38// Phone shapes. Each needs a boundary that is not a letter, digit, slash, dot,
39// hyphen, hash, equals sign or @ on either side, so ids and paths stay.
40const LEFT = String.raw`(?<![\w/\\.#=@+$£€₹-])`
41const RIGHT = String.raw`(?![\w/\\@%-]|\.\d|,\d)`
42const PHONE_RES: RegExp[] = [
43  // International: +44 7700 900123, +1 (415) 555-0132, +91 98765 43210, +919876543210
44  new RegExp(String.raw`${LEFT}\+\d{1,3}(?:[ .-]?\(?\d{1,5}\)?){1,6}${RIGHT}`, 'g'),
45  // US: (415) 555-0132, 415-555-0132, 415.555.0132, 415 555 0132, 1-415-555-0132
46  new RegExp(String.raw`${LEFT}(?:1[ .-])?(?:\(\d{3}\)\s?|\d{3}[ .-])\d{3}[ .-]\d{4}${RIGHT}`, 'g'),
47  // UK: 07700 900123, 020 7946 0958, (020) 7946 0958, 01632 960983
48  new RegExp(String.raw`${LEFT}(?:\(0\d{2,4}\)|0\d{2,4})[ -]?\d{3,4}[ -]?\d{3,4}${RIGHT}`, 'g'),
49  // India: 98765 43210, 98765-43210, 098765 43210, 9876543210
50  new RegExp(String.raw`${LEFT}0?[6-9]\d{4}[ -]?\d{5}${RIGHT}`, 'g'),
51]
52
53// A date or a time is never a phone, whatever its separators.
54const DATE_RES: RegExp[] = [
55  /^\(?(?:19|20)\d{2}[ .-](?:0?[1-9]|1[0-2])[ .-](?:0?[1-9]|[12]\d|3[01])\b/,
56  /^\(?(?:0?[1-9]|[12]\d|3[01])[ .-](?:0?[1-9]|1[0-2])[ .-](?:19|20)\d{2}\b/,
57  /^\(?(?:0?[1-9]|1[0-2])[ .-](?:0?[1-9]|[12]\d|3[01])[ .-](?:19|20)\d{2}\b/,
58]
59// Runs of plain years, "2024 2025 2026", read like a number but are not one.
60const YEARS_RE = /^(?:(?:19|20)\d{2}[ .-]?){2,}$/
61const NON_DIGIT_RE = /\D/g
62const PLUS_RE = /^\+/
63const LAST_GROUP_RE = /[ .-]?\(?\d+\)?$/
64const QUICK_RE = /[@\d:]/
65
66// Names. Only where the text says it is a person: "Name <email>", a name in
67// brackets or a table cell next to an email, a From:/To:/Cc: line, or a name
68// key in JSON. Never a guess at every capitalised word.
69const WORD = String.raw`\p{Lu}[\p{L}\p{M}'’.-]*`
70// Lowercase particles inside a name: Ben van Sprundel, Ana de la Cruz.
71const PARTICLE = String.raw`(?:van|von|de|der|den|da|di|du|la|le|del|dos|das|bin|ibn|al)`
72const WORDS = String.raw`${WORD}(?:[ \t]+(?:${PARTICLE}[ \t]+){0,2}${WORD}){0,3}`
73const NB = String.raw`(?<![\p{L}\p{N}_@.])`
74// Each email is looked at once, with a short window of text either side of
75// it, instead of running every name pattern over the whole message.
76const WINDOW = 80
77const NAME_WORD_RE = new RegExp(String.raw`^${WORD}$`, 'u')
78const PARTICLES = new Set(['van', 'von', 'de', 'der', 'den', 'da', 'di', 'du', 'la', 'le', 'del', 'dos', 'das', 'bin', 'ibn', 'al'])
79const BEFORE_SEPS = '<(,:|-–—'
80const LEAD_PUNCT = '*_"\'([|>'
81// "Jane Doe" <jane@
82const QUOTED_RE = /"([^"\n<>@]{1,60})"[ \t]*<[ \t]*$/
83// jane@x.com (Jane Doe) | jane@x.com | Jane Doe |
84const AFTER_RE = new RegExp(String.raw`^>?[ \t]*(?:\([ \t]*(${WORDS})[ \t]*\)|\|[ \t]*(${WORDS})[ \t]*\|)`, 'u')
85// Words that open a phrase but are not part of the name after them.
86const STOP = new Set([
87  'From', 'To', 'Cc', 'Bcc', 'Mail', 'Email', 'E-mail', 'Contact', 'Call', 'Hi', 'Hello', 'Hey', 'Dear',
88  'Thanks', 'Ask', 'Ping', 'Message', 'Write', 'Send', 'Reply', 'By', 'And', 'Or', 'The', 'Sender',
89  'Recipient', 'With', 'Via', 'Name', 'Owner', 'Lead', 'Customer', 'Client',
90])
91// A From:, To:, Cc: style line, markdown bold allowed around the label.
92const HEADER_RE = /^([ \t>*_-]*[*_]{0,2}(?:From|To|Cc|Bcc|Reply-To|Sender|Recipients?|Attendees?|Organi[sz]er|Invitees?|Guests?|Contact|Full[ _]name|Name)[*_]{0,2}[ \t]*:[*_]{0,2}[ \t]*)([^\n]*)$/gim
93const PART_SPLIT_RE = /,|;|[ \t]+and[ \t]+|[ \t]+&[ \t]+/g
94const PART_NAME_RE = new RegExp(String.raw`^[ \t]*[*_"']{0,2}(${WORDS})[*_"']{0,2}[ \t]*(?=$|<|\(|\[)`, 'u')
95// JSON: "full_name": "Jane Doe", and "name" inside an object that has an email.
96const NAME_KEY_JSON_RE = /"(?:full_?name|first_?name|last_?name|display_?name|given_?name|family_?name|sender_?name|from_?name|contact_?name|person_?name|author_?name|owner_?name)"\s*:\s*"([^"\\\n]{1,80})"/gi
97const FLAT_OBJECT_RE = /\{[^{}]{0,3000}\}/g
98const HAS_EMAIL_KEY_RE = /"e-?mail(?:_?address)?"\s*:/i
99const NAME_JSON_RE = /"name"\s*:\s*"([^"\\\n]{1,80})"/g
100const STARTS_LETTER_RE = /^[\p{L}]/u
101const SPACE_RE = /\s/
102const NOT_SPACE_RE = /\S/gu
103
104/** Keys whose string value is a person's name (any case, _ optional). */
105export const NAME_KEY_RE = /^(?:full_?name|first_?name|last_?name|display_?name|given_?name|family_?name|sender_?name|from_?name|contact_?name|person_?name|author_?name|owner_?name)$/i
106const EMAIL_KEY_RE = /^e-?mail(?:_?address)?$/i
107
108function digits(s: string) {
109  return s.replace(NON_DIGIT_RE, '').length
110}
111
112function isPhone(hit: string) {
113  const n = digits(hit)
114  if (n < 9 || n > 15) return false
115  const bare = hit.replace(PLUS_RE, '')
116  if (DATE_RES.some(r => r.test(bare))) return false
117  if (YEARS_RE.test(bare)) return false
118  return true
119}
120
121// How much of a hit is the phone: the whole, or less once trailing groups that
122// belong to the next number (a year after it) are cut off. 0 when none of it.
123function phoneLength(hit: string) {
124  let h = hit
125  while (h) {
126    if (isPhone(h)) return h.length
127    const cut = h.replace(LAST_GROUP_RE, '')
128    if (cut === h || digits(cut) < 9) return 0
129    h = cut
130  }
131  return 0
132}
133
134// Which characters are already taken, one byte each: an overlap test is then
135// a short scan of the hit, not a pass over every span found so far.
136function taken(used: Uint8Array, a: number, b: number) {
137  for (let i = a; i < b; i++) if (used[i]) return true
138  return false
139}
140
141function take(used: Uint8Array, a: number, b: number) {
142  used.fill(1, a, b)
143}
144
145// A name found at `at`: leading opener words (From, Hi, Contact) are dropped,
146// and it needs at least `min` words left.
147function addName(spans: Span[], name: string, at: number, min: number) {
148  const words = name.split(/([ \t]+)/)
149  let start = at
150  while (words.length && STOP.has(words[0] ?? '')) {
151    start += (words[0] ?? '').length + (words[1] ?? '').length
152    words.splice(0, 2)
153  }
154  const kept = words.filter((_, i) => i % 2 === 0)
155  if (kept.length < min || kept.length === 0) return
156  const text = words.join('').replace(/[ \t]+$/, '')
157  if (!text) return
158  spans.push({ a: start, b: start + text.length, kind: 'name' })
159}
160
161// Walks back from an email over a separator (< ( , : | -) and up to four
162// capitalised words. Plain string steps, no regex over the whole window.
163function isBlank(c: string | undefined) {
164  return c === ' ' || c === '\t'
165}
166
167function nameBefore(text: string, end: number, spans: Span[]) {
168  let i = end
169  while (isBlank(text[i - 1])) i--
170  let sep = text[i - 1] ?? ''
171  if (!sep || !BEFORE_SEPS.includes(sep)) return
172  i--
173  while (isBlank(text[i - 1])) i--
174  // "Jane Doe, <jane@x.com>": the bracket sits after the real separator.
175  const prev = text[i - 1] ?? ''
176  if (sep === '<' && prev && prev !== '<' && BEFORE_SEPS.includes(prev)) {
177    sep = prev
178    i--
179    while (isBlank(text[i - 1])) i--
180  }
181  const nameEnd = i
182  const floor = Math.max(0, end - WINDOW)
183  let start = -1
184  let words = 0
185  while (words < 4 && i > floor) {
186    // The word that ends at i.
187    let j = i
188    while (j > floor && !SPACE_RE.test(text[j - 1] ?? ' ')) j--
189    let w = j
190    while (w < i && LEAD_PUNCT.includes(text[w] ?? '')) w++
191    const word = text.slice(w, i)
192    if (NAME_WORD_RE.test(word)) {
193      start = w
194      words++
195    } else if (!(PARTICLES.has(word) && words > 0 && w === j)) break
196    // Punctuation before a word, a line start or a wide gap ends the name.
197    if (w !== j || j <= floor || !isBlank(text[j - 1])) break
198    i = j
199    while (isBlank(text[i - 1])) i--
200    if (j - i > 2) break
201  }
202  if (start < 0 || nameEnd <= start) return
203  addName(spans, text.slice(start, nameEnd), start, sep === '<' || sep === '(' ? 1 : 2)
204}
205
206function nameSpans(text: string, spans: Span[], emails: Span[]) {
207  for (const e of emails) {
208    let from = Math.max(0, e.a - WINDOW)
209    // Start the window on a word boundary so a cut word is not read as a name.
210    while (from > 0 && !SPACE_RE.test(text[from - 1] ?? ' ')) from++
211    const before = text.slice(from, e.a)
212    const q = QUOTED_RE.exec(before)
213    if (q && q[1]) addName(spans, q[1], from + (q.index ?? 0) + 1, 1)
214    else nameBefore(text, e.a, spans)
215    const after = text.slice(e.b, e.b + WINDOW)
216    const n = AFTER_RE.exec(after)
217    const name = n?.[1] ?? n?.[2]
218    if (n && name) addName(spans, name, e.b + (n.index ?? 0) + n[0].indexOf(name), n[1] ? 1 : 2)
219  }
220  if (text.includes(':')) {
221    HEADER_RE.lastIndex = 0
222    for (const m of text.matchAll(HEADER_RE)) {
223      const label = m[1] ?? ''
224      const rest = m[2] ?? ''
225      const at = (m.index ?? 0) + label.length
226      let last = 0
227      PART_SPLIT_RE.lastIndex = 0
228      const parts: Array<[string, number]> = []
229      for (const sep of rest.matchAll(PART_SPLIT_RE)) {
230        parts.push([rest.slice(last, sep.index), last])
231        last = (sep.index ?? 0) + sep[0].length
232      }
233      parts.push([rest.slice(last), last])
234      for (const [part, off] of parts) {
235        const pm = PART_NAME_RE.exec(part)
236        if (!pm || !pm[1]) continue
237        addName(spans, pm[1], at + off + part.indexOf(pm[1]), 1)
238      }
239    }
240  }
241  if (text.includes('"')) {
242    NAME_KEY_JSON_RE.lastIndex = 0
243    for (const m of text.matchAll(NAME_KEY_JSON_RE)) {
244      const v = m[1] ?? ''
245      if (STARTS_LETTER_RE.test(v)) spans.push({ a: (m.index ?? 0) + m[0].length - 1 - v.length, b: (m.index ?? 0) + m[0].length - 1, kind: 'name' })
246    }
247    if (text.includes('@')) {
248      FLAT_OBJECT_RE.lastIndex = 0
249      for (const o of text.matchAll(FLAT_OBJECT_RE)) {
250        if (!HAS_EMAIL_KEY_RE.test(o[0])) continue
251        NAME_JSON_RE.lastIndex = 0
252        for (const m of o[0].matchAll(NAME_JSON_RE)) {
253          const v = m[1] ?? ''
254          const end = (o.index ?? 0) + (m.index ?? 0) + m[0].length - 1
255          if (STARTS_LETTER_RE.test(v)) spans.push({ a: end - v.length, b: end, kind: 'name' })
256        }
257      }
258    }
259  }
260}
261
262/** Every private span in `text`, sorted and merged. */
263export function findSpans(text: string): Span[] {
264  const spans: Span[] = []
265  if (!text || typeof text !== 'string') return spans
266  const hasAt = text.includes('@')
267  if (hasAt) {
268    EMAIL_RE.lastIndex = 0
269    for (const m of text.matchAll(EMAIL_RE)) spans.push({ a: m.index ?? 0, b: (m.index ?? 0) + m[0].length, kind: 'email' })
270  }
271  const emails = spans.slice()
272  if (/\d/.test(text)) {
273    const used = new Uint8Array(text.length)
274    for (const e of emails) take(used, e.a, e.b)
275    const inLink = new Uint8Array(text.length)
276    URL_RE.lastIndex = 0
277    for (const m of text.matchAll(URL_RE)) take(inLink, m.index ?? 0, (m.index ?? 0) + m[0].length)
278    for (const re of MONEY_RES) {
279      re.lastIndex = 0
280      for (const m of text.matchAll(re)) {
281        const a = m.index ?? 0
282        const b = a + m[0].length
283        if (BARE_ARG_RE.test(m[0]) || taken(inLink, a, b) || taken(used, a, b)) continue
284        spans.push({ a, b, kind: 'amount' })
285        take(used, a, b)
286      }
287    }
288    for (const re of PHONE_RES) {
289      re.lastIndex = 0
290      for (const m of text.matchAll(re)) {
291        const a = m.index ?? 0
292        const n = phoneLength(m[0])
293        if (n === 0 || taken(inLink, a, a + m[0].length) || taken(used, a, a + n)) continue
294        spans.push({ a, b: a + n, kind: 'phone' })
295        take(used, a, a + n)
296      }
297    }
298  }
299  nameSpans(text, spans, emails)
300  if (spans.length < 2) return spans
301  spans.sort((x, y) => x.a - y.a || y.b - x.b)
302  const out: Span[] = []
303  for (const s of spans) {
304    const prev = out[out.length - 1]
305    if (prev && s.a <= prev.b) {
306      if (s.b > prev.b) prev.b = s.b
307    } else out.push({ ...s })
308  }
309  return out
310}
311
312/** A bar as long as `hit`: every character but a space becomes `glyph`. */
313export function bar(hit: string, glyph = BAR) {
314  return hit.replace(NOT_SPACE_RE, glyph)
315}
316
317/**
318 * Rewrites every private span of `text` with `draw(hit, kind)`. Returns the
319 * same string when nothing is private.
320 */
321export function redact(text: string, draw: (hit: string, kind: Kind) => string): string {
322  if (!text || typeof text !== 'string') return text
323  // Quick exit: nothing that could be private.
324  if (!QUICK_RE.test(text)) return text
325  const spans = findSpans(text)
326  if (spans.length === 0) return text
327  let out = ''
328  let at = 0
329  for (const s of spans) {
330    out += text.slice(at, s.a) + draw(text.slice(s.a, s.b), s.kind)
331    at = s.b
332  }
333  return out + text.slice(at)
334}
335
336// Rows draw again on every scroll and redraw, so a long text is masked once
337// per glyph and kept.
338const cache = new Map<string, string>()
339const CACHE_MAX = 400
340
341/** Hides emails, phone numbers, money amounts and names in one string. */
342export function mask(text: string, glyph = BAR): string {
343  if (!text || typeof text !== 'string') return text
344  const long = text.length >= 200
345  const key = long ? glyph + text : ''
346  if (long) {
347    const hit = cache.get(key)
348    if (hit !== undefined) return hit
349  }
350  const out = redact(text, hit => bar(hit, glyph))
351  if (long) {
352    if (cache.size >= CACHE_MAX) {
353      const first = cache.keys().next().value
354      if (first !== undefined) cache.delete(first)
355    }
356    cache.set(key, out)
357  }
358  return out
359}
360
361/**
362 * Masks every string inside plain data (a tool's input or result), keeping its
363 * shape and keys, so a result still fits its tool's schema. Returns the same
364 * value when nothing changed.
365 */
366export function maskDeep<T>(value: T, glyph = BAR, depth = 0): T {
367  if (typeof value === 'string') return mask(value, glyph) as T
368  if (value === null || typeof value !== 'object' || depth > 30) return value
369  if (Array.isArray(value)) {
370    let changed = false
371    const out = value.map(v => {
372      const m = maskDeep(v, glyph, depth + 1)
373      if (m !== v) changed = true
374      return m
375    })
376    return (changed ? out : value) as T
377  }
378  const proto = Object.getPrototypeOf(value)
379  if (proto !== Object.prototype && proto !== null) return value
380  const entries = Object.entries(value as Record<string, unknown>)
381  const hasEmail = entries.some(([k]) => EMAIL_KEY_RE.test(k))
382  let changed = false
383  const out: Record<string, unknown> = {}
384  for (const [k, v] of entries) {
385    let m: unknown
386    // Ids are never private data and must reach the engine as they were.
387    if (k === 'tool_use_id' || k === 'id') m = v
388    else if (typeof v === 'string' && v && (NAME_KEY_RE.test(k) || (hasEmail && k === 'name'))) m = bar(v, glyph)
389    else m = maskDeep(v, glyph, depth + 1)
390    if (m !== v) changed = true
391    out[k] = m
392  }
393  return (changed ? out : value) as T
394}
395
396// Run every rule once at load, so the first row drawn after /screen-share does
397// not pay for building the patterns.
398mask('From: Jane Doe <jane@x.co> (Bob Lee) | Ann Wu | +44 7700 900123, $4,250.00, "full_name": "A", {"name": "B", "email": "c"}')
399cache.clear()
400

1export type ScreenShareMode = 'on' | 'off'
2
3declare module 'claude-code' {
4  interface PluginState {
5    'screen-share': {
6      /** True while Screen-Share Mode hides private data on screen. */
7      on: boolean
8    }
9  }
10}
11