Hold Button

// SPDX-License-Identifier: MIT
// Copyright (c) 2025 kokonutUI
// Source: https://github.com/kokonut-labs/kokonutui/blob/83eec6d/components/kokonutui/hold-button.tsx
// Modified by Motif; see the item's provenance.
import { animate, motion, useMotionValue, useReducedMotion, useTransform, type AnimationPlaybackControls } from 'motion/react'
import { cn } from '@motif/runtime'
import { useEffect, useRef, useState, type CSSProperties, type KeyboardEvent } from 'react'
/* @motif:defaults */
export const defaults = {
  holdDuration: 1.6,
  color: '#f43f5e',
  radius: 14,
  width: 232,
  icon: 'trash',
  label: 'Hold to delete',
  holdLabel: 'Keep holding',
  doneLabel: 'Deleted',
}
/* @motif:end */
export type HoldButtonProps = Partial<typeof defaults> & {
  className?: string
  style?: CSSProperties
  /** 从外部驱动「按住」（演示的自动播放用）；真实按压照常生效。 */
  holding?: boolean
  onComplete?: () => void
}
const ICONS: Record<string, string> = {
  trash: 'M4 7h16M10 11v6m4-6v6M6 7l1 12a2 2 0 0 0 2 2h6a2 2 0 0 0 2-2l1-12M9 7V4h6v3',
  power: 'M12 3v9m5.7-6.3a8 8 0 1 1-11.4 0',
  lock: 'M7 11V8a5 5 0 0 1 10 0v3M6 11h12a1 1 0 0 1 1 1v7a1 1 0 0 1-1 1H6a1 1 0 0 1-1-1v-7a1 1 0 0 1 1-1Z',
}
const DONE_SECONDS = 1.5
/**
 * 长按确认：按住期间颜色从左向右填满，填满才触发 onComplete。
 * 完成后需要先松手才能再次按住，避免长按不放时反复触发。
 */
export function HoldButton({ className, style, holding, onComplete, ...props }: HoldButtonProps) {
  const { holdDuration, color, radius, width, icon, label, holdLabel, doneLabel } = { ...defaults, ...props }
  const reduced = useReducedMotion()
  const progress = useMotionValue(0)
  const timer = useMotionValue(0)
  const [pressed, setPressed] = useState(false)
  const [done, setDone] = useState(false)
  const active = pressed || Boolean(holding)
  const running = useRef<AnimationPlaybackControls | null>(null)
  const needsRelease = useRef(false)
  const completeRef = useRef(onComplete)
  completeRef.current = onComplete
  useEffect(() => {
    if (!active) needsRelease.current = false
    if (done) return
    running.current?.stop()
    if (active && !needsRelease.current) {
      running.current = animate(progress, 1, {
        duration: holdDuration,
        ease: 'linear',
        onComplete: () => {
          needsRelease.current = true
          setDone(true)
          completeRef.current?.()
        },
      })
    } else {
      running.current = animate(progress, 0, { duration: 0.28, ease: 'easeOut' })
    }
    return () => running.current?.stop()
  }, [active, done, holdDuration, progress])
  // 完成状态停留一会儿再复位；用 motion 的时钟而不是 setTimeout，录屏时也是确定的。
  useEffect(() => {
    if (!done) return
    timer.set(0)
    const controls = animate(timer, 1, {
      duration: DONE_SECONDS,
      ease: 'linear',
      onComplete: () => {
        setDone(false)
        animate(progress, 0, { duration: 0.4, ease: 'easeOut' })
      },
    })
    return () => controls.stop()
  }, [done, timer, progress])
  const fillX = useTransform(progress, (v) => `${(v - 1) * 100}%`)
  const iconScale = useTransform(progress, [0, 1], [1, 1.2])
  const holdingNow = active && !done && !needsRelease.current
  const start = () => setPressed(true)
  const end = () => setPressed(false)
  const onKeyDown = (event: KeyboardEvent) => {
    if ((event.key === ' ' || event.key === 'Enter') && !event.repeat) {
      event.preventDefault()
      start()
    }
  }
  const onKeyUp = (event: KeyboardEvent) => {
    if (event.key === ' ' || event.key === 'Enter') end()
  }
  const text = (visible: boolean) => ({ opacity: visible ? 1 : 0, y: reduced ? 0 : visible ? 0 : 6 })
  const showHold = holdingNow
  return (
    <motion.button
      type="button"
      onPointerDown={(event) => {
        if (event.button !== 0) return
        event.currentTarget.setPointerCapture?.(event.pointerId)
        start()
      }}
      onPointerUp={end}
      onPointerCancel={end}
      onLostPointerCapture={end}
      onKeyDown={onKeyDown}
      onKeyUp={onKeyUp}
      onBlur={end}
      onContextMenu={(event) => event.preventDefault()}
      animate={{ scale: !reduced && holdingNow ? 0.975 : 1 }}
      transition={{ type: 'spring', visualDuration: 0.25, bounce: 0.25 }}
      className={cn(
        'relative inline-flex touch-none items-center justify-center overflow-hidden border py-3 text-sm font-medium tracking-tight outline-none select-none focus-visible:ring-2 focus-visible:ring-ring',
        className,
      )}
      style={
        {
          '--hb': color,
          width,
          borderRadius: radius,
          background: 'color-mix(in oklab, var(--hb) 12%, transparent)',
          borderColor: 'color-mix(in oklab, var(--hb) 38%, transparent)',
          color: 'color-mix(in oklab, var(--hb) 78%, var(--foreground))',
          ...style,
        } as CSSProperties
      }
    >
      {/* 填充层整体向左偏移 (1 - progress)，用 transform 推进而不是改 width。 */}
      <motion.span
        aria-hidden
        className="absolute inset-0"
        style={{
          x: fillX,
          background: 'color-mix(in oklab, var(--hb) 34%, transparent)',
          boxShadow: '2px 0 14px color-mix(in oklab, var(--hb) 70%, transparent)',
          borderRight: '1.5px solid var(--hb)',
        }}
      />
      <span className="relative z-10 grid place-items-center">
        {/* 三段文案叠在同一格里，按钮宽度不随状态变化。 */}
        <span className="col-start-1 row-start-1 inline-flex items-center gap-2">
          <span className="relative grid size-4 place-items-center">
            <motion.svg
              viewBox="0 0 24 24"
              className="col-start-1 row-start-1 size-4"
              fill="none"
              stroke="currentColor"
              strokeWidth="2"
              strokeLinecap="round"
              strokeLinejoin="round"
              style={{ scale: reduced ? 1 : iconScale }}
              animate={{ opacity: done ? 0 : 1 }}
              transition={{ duration: 0.15 }}
              aria-hidden
            >
              <path d={ICONS[icon] ?? ICONS.trash} />
            </motion.svg>
            <motion.svg
              viewBox="0 0 24 24"
              className="absolute inset-0 size-4"
              fill="none"
              stroke="currentColor"
              strokeWidth="2.6"
              strokeLinecap="round"
              strokeLinejoin="round"
              animate={{ opacity: done ? 1 : 0, scale: done || reduced ? 1 : 0.6 }}
              transition={{ duration: 0.2 }}
              aria-hidden
            >
              <path d="m5 12.5 4.5 4.5L19 7.5" />
            </motion.svg>
          </span>
          <span className="grid">
            <motion.span className="col-start-1 row-start-1" animate={text(!showHold && !done)} transition={{ duration: 0.18 }}>
              {label}
            </motion.span>
            <motion.span className="col-start-1 row-start-1" animate={text(showHold)} transition={{ duration: 0.18 }}>
              {holdLabel}
            </motion.span>
            <motion.span className="col-start-1 row-start-1" animate={text(done)} transition={{ duration: 0.18 }}>
              {doneLabel}
            </motion.span>
          </span>
        </span>
      </span>
      <span className="sr-only" aria-live="polite">
        {done ? doneLabel : ''}
      </span>
    </motion.button>
  )
}