Momento/memento-note/components/brainstorm/ghost-cursor.tsx

'use client'

import React, { useEffect, useRef } from 'react'
import { motion, AnimatePresence } from 'motion/react'

interface GhostCursorProps {
  isActive: boolean
  containerRef: React.RefObject<HTMLDivElement | null>
  targetId?: string | null
}

export function GhostCursor({ isActive, containerRef, targetId }: GhostCursorProps) {
  const positionRef = useRef({ x: 0, y: 0 })
  const visibleRef = useRef(false)
  const elRef = useRef<HTMLDivElement>(null)
  const rafRef = useRef<number | null>(null)
  const targetRef = useRef({ x: 0, y: 0 })
  const initializedRef = useRef(false)
  const targetIdRef = useRef(targetId)
  targetIdRef.current = targetId
  const isActiveRef = useRef(isActive)
  isActiveRef.current = isActive

  useEffect(() => {
    if (!isActive) {
      visibleRef.current = false
      initializedRef.current = false
      if (elRef.current) elRef.current.style.opacity = '0'
      if (rafRef.current) cancelAnimationFrame(rafRef.current)
      return
    }

    let angle = Math.random() * Math.PI * 2

    const init = () => {
      const container = containerRef.current
      if (!container) { rafRef.current = requestAnimationFrame(init); return }
      const rect = container.getBoundingClientRect()
      if (rect.width === 0 || rect.height === 0) { rafRef.current = requestAnimationFrame(init); return }

      const cx = rect.width / 2
      const cy = rect.height / 2
      targetRef.current = { x: cx + (Math.random() - 0.5) * 200, y: cy + (Math.random() - 0.5) * 200 }
      positionRef.current = { ...targetRef.current }
      initializedRef.current = true
      visibleRef.current = true
      if (elRef.current) {
        elRef.current.style.opacity = '1'
        elRef.current.style.transform = `translate(${positionRef.current.x}px, ${positionRef.current.y}px)`
      }
    }

    rafRef.current = requestAnimationFrame(init)

    const tick = () => {
      if (!isActiveRef.current || !initializedRef.current) {
        rafRef.current = requestAnimationFrame(tick)
        return
      }

      const container = containerRef.current
      if (!container) { rafRef.current = requestAnimationFrame(tick); return }
      const containerRect = container.getBoundingClientRect()
      if (containerRect.width === 0 || containerRect.height === 0) { rafRef.current = requestAnimationFrame(tick); return }

      const cx = containerRect.width / 2
      const cy = containerRect.height / 2
      let tx = targetRef.current.x
      let ty = targetRef.current.y

      const currentTargetId = targetIdRef.current
      if (currentTargetId) {
        const nodeElement = container.querySelector(`[data-id="${currentTargetId}"]`) as HTMLElement | null
        if (nodeElement) {
          const nodeRect = nodeElement.getBoundingClientRect()
          tx = nodeRect.left - containerRect.left + nodeRect.width / 2
          ty = nodeRect.top - containerRect.top + nodeRect.height / 2
        }
      }

      const prev = positionRef.current
      const dx = tx - prev.x
      const dy = ty - prev.y
      const dist = Math.sqrt(dx * dx + dy * dy)

      if (!currentTargetId && dist < 20) {
        angle = Math.random() * Math.PI * 2
        const radius = 150 + Math.random() * 200
        tx = cx + Math.cos(angle) * radius
        ty = cy + Math.sin(angle) * radius
        targetRef.current = { x: tx, y: ty }
      }

      const speed = currentTargetId ? 0.12 : 0.04
      let newX = prev.x + (tx - prev.x) * speed
      let newY = prev.y + (ty - prev.y) * speed
      if (isNaN(newX)) newX = cx
      if (isNaN(newY)) newY = cy

      positionRef.current = { x: newX, y: newY }

      if (elRef.current) {
        elRef.current.style.transform = `translate(${newX}px, ${newY}px)`
      }

      rafRef.current = requestAnimationFrame(tick)
    }

    rafRef.current = requestAnimationFrame(tick)

    return () => {
      if (rafRef.current) cancelAnimationFrame(rafRef.current)
    }
  }, [isActive, containerRef])

  return (
    <div
      ref={elRef}
      className="absolute pointer-events-none z-50"
      style={{
        left: 0,
        top: 0,
        opacity: 0,
        transition: 'opacity 0.3s ease',
      }}
    >
      <div className="relative">
        <svg width="16" height="16" viewBox="0 0 16 16" fill="none">
          <path d="M0 0L16 6L8 8L6 16L0 0Z" fill="#a78bfa" />
        </svg>
        <div className="absolute -top-1 -right-1 w-3 h-3">
          <span className="absolute inline-flex h-full w-full animate-ping rounded-full bg-violet-400 opacity-50" />
          <span className="relative inline-flex rounded-full h-3 w-3 bg-violet-500" />
        </div>
        <div className="mt-3 ml-3 px-2 py-0.5 rounded-full text-[10px] font-bold text-white whitespace-nowrap shadow-lg bg-gradient-to-r from-violet-500 to-purple-600">
          AI ✦
        </div>
      </div>
    </div>
  )
}