oppi.li
source dump of claude code
1import { useMemo } from 'react'
2import { stringWidth } from '../../ink/stringWidth.js'
3import { type DOMElement, useAnimationFrame } from '../../ink.js'
4import type { SpinnerMode } from './types.js'
5
6export function useShimmerAnimation(
7 mode: SpinnerMode,
8 message: string,
9 isStalled: boolean,
10): [ref: (element: DOMElement | null) => void, glimmerIndex: number] {
11 const glimmerSpeed = mode === 'requesting' ? 50 : 200
12 // Pass null when stalled to unsubscribe from the clock — otherwise the
13 // setInterval keeps firing at 20fps even when the shimmer isn't visible.
14 // Notably, if the caller never attaches `ref` (e.g. conditional JSX),
15 // useTerminalViewport stays at its initial isVisible:true and the
16 // viewport-pause never kicks in, so this is the only stop mechanism.
17 const [ref, time] = useAnimationFrame(isStalled ? null : glimmerSpeed)
18 const messageWidth = useMemo(() => stringWidth(message), [message])
19
20 if (isStalled) {
21 return [ref, -100]
22 }
23
24 const cyclePosition = Math.floor(time / glimmerSpeed)
25 const cycleLength = messageWidth + 20
26
27 if (mode === 'requesting') {
28 return [ref, (cyclePosition % cycleLength) - 10]
29 }
30 return [ref, messageWidth + 10 - (cyclePosition % cycleLength)]
31}