timer.ts

import { useEffect } from 'react'

export class Timer {
  name: string
  lastTimestamp = 0
  counts = new Map<string, number>()
  durations = new Map<string, number>()
  totalDuration = 0
  totalCount = 0

  constructor(name: string) {
    this.name = name
  }

  prepare() {
    this.lastTimestamp = performance.now()
    this.totalCount += 1
  }

  slice(name: string) {
    const duration = performance.now() - this.lastTimestamp
    this.durations.set(name, (this.durations.get(name) ?? 0) + duration)
    this.counts.set(name, (this.counts.get(name) ?? 0) + 1)

    this.totalDuration += duration
    this.lastTimestamp = performance.now()
  }

  printSummary() {
    const sorted = Array.from(this.durations.entries()).sort((a, b) => b[1] - a[1])
    console.log('⏱️ Total:', this.name, this.totalDuration, this.totalDuration / this.totalCount, this.totalCount)
    for (const [name, duration] of sorted.slice(0, 10)) {
      const count = this.counts.get(name) ?? 0
      console.log(` - ${name}:`, duration, duration / count, count)
    }
  }

  usePrintSummary() {
    // eslint-disable-next-line react-hooks/rules-of-hooks
    useEffect(() => {
      const id = setTimeout(() => this.printSummary(), 5000)
      return () => clearTimeout(id)
    }, [])
  }
}