import Underlay from 'src/components/underlay.style.js'
import Panel from 'src/components/panel.style.js'
import Button from 'src/components/button.style.js'
import Text from 'src/components/text.style.js'
import Icon from 'src/components/icon.style.js'

const root = Underlay
const components = {
  Underlay,
  Panel,
  Button,
  Text,
  Icon
}

// This gives you an array of arrays of all possible unique (i.e. order-insensitive) combinations
const getAllPossibleCombinations = (array) => {
  const combos = [array.map(x => [x])]
  for (let comboSize = 2; comboSize <= array.length; comboSize++) {
    const previous = combos[combos.length - 1]
    const selfSet = new Set()
    const newCombos = previous.map(self => {
      self.forEach(x => selfSet.add(x))
      const nonSelf = array.filter(x => !selfSet.has(x))
      return nonSelf.map(x => [...self, x])
    })
    const flatCombos = newCombos.reduce((acc, x) => [...acc, ...x], [])
    combos.push(flatCombos)
  }
  return combos.reduce((acc, x) => [...acc, ...x], [])
}

export const init = () => {
  const rootName = root.name
  const rules = []

  const processInnerComponent = (component, parent) => {
    const {
      validInnerComponents,
      states: originalStates = {},
      variants: originalVariants = {}
    } = component

    const states = { normal: '', ...originalStates }
    const variants = { normal: '', ...originalVariants }
    const innerComponents = validInnerComponents.map(name => components[name])

    const stateCombinations = getAllPossibleCombinations(Object.keys(states))
    const stateVariantCombination = Object.keys(variants).map(variant => {
      return stateCombinations.map(state => ({ variant, state }))
    }).reduce((acc, x) => [...acc, ...x], [])

    stateVariantCombination.forEach(combination => {
      rules.push(({
        parent,
        component: component.name,
        state: combination.state,
        variant: combination.variant
      }))

      innerComponents.forEach(innerComponent => processInnerComponent(innerComponent, combination))
    })
  }

  processInnerComponent(components[rootName])
}