sgr.ts
ink/termio/sgr.ts
309
Lines
6400
Bytes
1
Exports
2
Imports
10
Keywords
What this is
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Beginner explanation
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How it is used
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Expert explanation
Architecturally, this file intersects with ui-flow. It contains 309 lines, 2 detected imports, and 1 detected exports.
Important relationships
Detected exports
applySGR
Keywords
codecontinuesubparamsparamsindexcoloncurrentlengthnamed_colorsparam
Detected imports
./types.js./types.js
Source notes
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Full source
/**
* SGR (Select Graphic Rendition) Parser
*
* Parses SGR parameters and applies them to a TextStyle.
* Handles both semicolon (;) and colon (:) separated parameters.
*/
import type { NamedColor, TextStyle, UnderlineStyle } from './types.js'
import { defaultStyle } from './types.js'
const NAMED_COLORS: NamedColor[] = [
'black',
'red',
'green',
'yellow',
'blue',
'magenta',
'cyan',
'white',
'brightBlack',
'brightRed',
'brightGreen',
'brightYellow',
'brightBlue',
'brightMagenta',
'brightCyan',
'brightWhite',
]
const UNDERLINE_STYLES: UnderlineStyle[] = [
'none',
'single',
'double',
'curly',
'dotted',
'dashed',
]
type Param = { value: number | null; subparams: number[]; colon: boolean }
function parseParams(str: string): Param[] {
if (str === '') return [{ value: 0, subparams: [], colon: false }]
const result: Param[] = []
let current: Param = { value: null, subparams: [], colon: false }
let num = ''
let inSub = false
for (let i = 0; i <= str.length; i++) {
const c = str[i]
if (c === ';' || c === undefined) {
const n = num === '' ? null : parseInt(num, 10)
if (inSub) {
if (n !== null) current.subparams.push(n)
} else {
current.value = n
}
result.push(current)
current = { value: null, subparams: [], colon: false }
num = ''
inSub = false
} else if (c === ':') {
const n = num === '' ? null : parseInt(num, 10)
if (!inSub) {
current.value = n
current.colon = true
inSub = true
} else {
if (n !== null) current.subparams.push(n)
}
num = ''
} else if (c >= '0' && c <= '9') {
num += c
}
}
return result
}
function parseExtendedColor(
params: Param[],
idx: number,
): { r: number; g: number; b: number } | { index: number } | null {
const p = params[idx]
if (!p) return null
if (p.colon && p.subparams.length >= 1) {
if (p.subparams[0] === 5 && p.subparams.length >= 2) {
return { index: p.subparams[1]! }
}
if (p.subparams[0] === 2 && p.subparams.length >= 4) {
const off = p.subparams.length >= 5 ? 1 : 0
return {
r: p.subparams[1 + off]!,
g: p.subparams[2 + off]!,
b: p.subparams[3 + off]!,
}
}
}
const next = params[idx + 1]
if (!next) return null
if (
next.value === 5 &&
params[idx + 2]?.value !== null &&
params[idx + 2]?.value !== undefined
) {
return { index: params[idx + 2]!.value! }
}
if (next.value === 2) {
const r = params[idx + 2]?.value
const g = params[idx + 3]?.value
const b = params[idx + 4]?.value
if (
r !== null &&
r !== undefined &&
g !== null &&
g !== undefined &&
b !== null &&
b !== undefined
) {
return { r, g, b }
}
}
return null
}
export function applySGR(paramStr: string, style: TextStyle): TextStyle {
const params = parseParams(paramStr)
let s = { ...style }
let i = 0
while (i < params.length) {
const p = params[i]!
const code = p.value ?? 0
if (code === 0) {
s = defaultStyle()
i++
continue
}
if (code === 1) {
s.bold = true
i++
continue
}
if (code === 2) {
s.dim = true
i++
continue
}
if (code === 3) {
s.italic = true
i++
continue
}
if (code === 4) {
s.underline = p.colon
? (UNDERLINE_STYLES[p.subparams[0]!] ?? 'single')
: 'single'
i++
continue
}
if (code === 5 || code === 6) {
s.blink = true
i++
continue
}
if (code === 7) {
s.inverse = true
i++
continue
}
if (code === 8) {
s.hidden = true
i++
continue
}
if (code === 9) {
s.strikethrough = true
i++
continue
}
if (code === 21) {
s.underline = 'double'
i++
continue
}
if (code === 22) {
s.bold = false
s.dim = false
i++
continue
}
if (code === 23) {
s.italic = false
i++
continue
}
if (code === 24) {
s.underline = 'none'
i++
continue
}
if (code === 25) {
s.blink = false
i++
continue
}
if (code === 27) {
s.inverse = false
i++
continue
}
if (code === 28) {
s.hidden = false
i++
continue
}
if (code === 29) {
s.strikethrough = false
i++
continue
}
if (code === 53) {
s.overline = true
i++
continue
}
if (code === 55) {
s.overline = false
i++
continue
}
if (code >= 30 && code <= 37) {
s.fg = { type: 'named', name: NAMED_COLORS[code - 30]! }
i++
continue
}
if (code === 39) {
s.fg = { type: 'default' }
i++
continue
}
if (code >= 40 && code <= 47) {
s.bg = { type: 'named', name: NAMED_COLORS[code - 40]! }
i++
continue
}
if (code === 49) {
s.bg = { type: 'default' }
i++
continue
}
if (code >= 90 && code <= 97) {
s.fg = { type: 'named', name: NAMED_COLORS[code - 90 + 8]! }
i++
continue
}
if (code >= 100 && code <= 107) {
s.bg = { type: 'named', name: NAMED_COLORS[code - 100 + 8]! }
i++
continue
}
if (code === 38) {
const c = parseExtendedColor(params, i)
if (c) {
s.fg =
'index' in c
? { type: 'indexed', index: c.index }
: { type: 'rgb', ...c }
i += p.colon ? 1 : 'index' in c ? 3 : 5
continue
}
}
if (code === 48) {
const c = parseExtendedColor(params, i)
if (c) {
s.bg =
'index' in c
? { type: 'indexed', index: c.index }
: { type: 'rgb', ...c }
i += p.colon ? 1 : 'index' in c ? 3 : 5
continue
}
}
if (code === 58) {
const c = parseExtendedColor(params, i)
if (c) {
s.underlineColor =
'index' in c
? { type: 'indexed', index: c.index }
: { type: 'rgb', ...c }
i += p.colon ? 1 : 'index' in c ? 3 : 5
continue
}
}
if (code === 59) {
s.underlineColor = { type: 'default' }
i++
continue
}
i++
}
return s
}