| 1 | interface StyleTarget { |
| 2 | style: { |
| 3 | setProperty(name: string, value: string): void; |
| 4 | }; |
| 5 | } |
| 6 | |
| 7 | interface AriaTarget { |
| 8 | setAttribute(name: string, value: string): void; |
| 9 | } |
| 10 | |
| 11 | interface RafResizeUpdaterOptions { |
| 12 | target: StyleTarget; |
| 13 | separator?: AriaTarget | null; |
| 14 | cssVar: string; |
| 15 | onApply?: (value: number) => void; |
| 16 | } |
| 17 | |
| 18 | export interface RafResizeUpdater { |
| 19 | schedule(value: number): void; |
| 20 | flush(): void; |
| 21 | cancel(): void; |
| 22 | } |
| 23 | |
| 24 | export interface PointerResizeLifecycle { |
| 25 | /** Finish once, remove every listener, and release pointer capture. */ |
| 26 | finish(): void; |
| 27 | } |
| 28 | |
| 29 | /** |
| 30 | * Own one pointer-resize gesture across capture loss, cancellation, blur, and |
| 31 | * component cleanup. Every terminal path calls onFinish exactly once. |
| 32 | */ |
| 33 | export function createPointerResizeLifecycle({ |
| 34 | separator, |
| 35 | pointerId, |
| 36 | onMove, |
| 37 | onFinish, |
| 38 | }: { |
| 39 | separator: HTMLElement; |
| 40 | pointerId: number; |
| 41 | onMove: (event: PointerEvent) => void; |
| 42 | onFinish: () => void; |
| 43 | }): PointerResizeLifecycle { |
| 44 | let active = true; |
| 45 | |
| 46 | function removeListeners() { |
| 47 | window.removeEventListener("pointermove", handleMove); |
| 48 | window.removeEventListener("pointerup", handlePointerDone); |
| 49 | window.removeEventListener("pointercancel", handlePointerDone); |
| 50 | window.removeEventListener("blur", finish); |
| 51 | separator.removeEventListener("lostpointercapture", handlePointerDone); |
| 52 | } |
| 53 | |
| 54 | function finish() { |
| 55 | if (!active) return; |
| 56 | active = false; |
| 57 | removeListeners(); |
| 58 | try { |
| 59 | if (separator.hasPointerCapture(pointerId)) separator.releasePointerCapture(pointerId); |
| 60 | } catch { |
| 61 | // WebView2 can release capture before the terminal pointer event. |
| 62 | } |
| 63 | onFinish(); |
| 64 | } |
| 65 | |
| 66 | function handleMove(event: PointerEvent) { |
| 67 | if (event.pointerId === pointerId) onMove(event); |
| 68 | } |
| 69 | |
| 70 | function handlePointerDone(event: PointerEvent) { |
| 71 | if (event.pointerId === pointerId) finish(); |
| 72 | } |
| 73 | |
| 74 | try { |
| 75 | separator.setPointerCapture(pointerId); |
| 76 | } catch { |
| 77 | // Pointer capture is optional in older embedded browser runtimes. |
| 78 | } |
| 79 | window.addEventListener("pointermove", handleMove); |
| 80 | window.addEventListener("pointerup", handlePointerDone); |
| 81 | window.addEventListener("pointercancel", handlePointerDone); |
| 82 | window.addEventListener("blur", finish); |
| 83 | separator.addEventListener("lostpointercapture", handlePointerDone); |
| 84 | |
| 85 | return { finish }; |
| 86 | } |
| 87 | |
| 88 | function roundedPixel(value: number): number { |
| 89 | return Math.round(value); |
| 90 | } |
| 91 | |
| 92 | export function createRafResizeUpdater({ target, separator, cssVar, onApply }: RafResizeUpdaterOptions): RafResizeUpdater { |
| 93 | let frame: number | null = null; |
| 94 | let latest: number | null = null; |
| 95 | |
| 96 | const apply = () => { |
| 97 | frame = null; |
| 98 | if (latest === null) return; |
| 99 | const rounded = roundedPixel(latest); |
| 100 | target.style.setProperty(cssVar, `${rounded}px`); |
| 101 | separator?.setAttribute("aria-valuenow", String(rounded)); |
| 102 | onApply?.(rounded); |
| 103 | }; |
| 104 | |
| 105 | return { |
| 106 | schedule(value: number) { |
| 107 | latest = value; |
| 108 | if (frame !== null) return; |
| 109 | frame = requestAnimationFrame(apply); |
| 110 | }, |
| 111 | flush() { |
| 112 | if (frame !== null) { |
| 113 | cancelAnimationFrame(frame); |
| 114 | frame = null; |
| 115 | } |
| 116 | apply(); |
| 117 | }, |
| 118 | cancel() { |
| 119 | if (frame === null) return; |
| 120 | cancelAnimationFrame(frame); |
| 121 | frame = null; |
| 122 | }, |
| 123 | }; |
| 124 | } |
| 125 |