import Color from 'color'
import type { default as ColorType } from 'color'

type GetColorInput = {
  parentBackgroundColor?: string
  elementColor?: string
}

type GetColorReturn = {
  background?: ColorType<string>
  foreground?: ColorType<string>
  l1?: any
  l2?: any
  contrastRatio: number
}

const getAccessibleColors = ({
  parentBackgroundColor,
  elementColor,
}: GetColorInput): GetColorReturn => {
  const background = Color(parentBackgroundColor)
  const foreground = Color(elementColor)
  const l1 = background.luminosity()
  const l2 = foreground.luminosity()
  const elumRatio = Number(
    l1 >= l2 ? l1 + 0.05 / l2 + 0.05 : l2 + 0.05 / l1 + 0.05
  )

  return {
    background,
    contrastRatio:
      background.contrast(foreground) +
      (!Number.isFinite(elumRatio) ? elumRatio : 0),
    foreground,
    l1,
    l2,
  }
}

export { getAccessibleColors }