import { toPrecision } from '../utils/numbers'

export function value2per(value: number, scale: number[]) {
  const range = scale.length - 1
  let ps = 0
  scale.forEach((s, i) => {
    if (value > s) ps = i
  })

  // end
  if (ps >= range) return 1

  const min = scale[ps]
  const max = scale[ps + 1]

  return (ps + (value - min) / (max - min)) / range
}

export function per2value(per: number, scale: number[], step = 1) {
  const range = scale.length - 1

  if (step === 0) return scale[Math.round(per * range)]

  if (per >= 1) return scale[range]
  const ps = Math.floor(per * range)
  const min = scale[ps]
  const max = scale[ps + 1]
  const count = (max - min) / step
  const sper = (per - ps / range) * range

  return toPrecision(min + Math.round(sper * count) * step)
}