import removeMeta from './removeMeta'
const dlv = require('dlv')
import escapeClassName from 'css.escape'
import { ensureArray } from './array'
import { remToPx } from './remToPx'
import stringifyObject from 'stringify-object'
import isObject from './isObject'

export function stringifyConfigValue(x: any): string {
  if (isObject(x)) return `${Object.keys(x).length} values`
  if (typeof x === 'function') return 'ƒ'
  return stringifyObject(x, {
    inlineCharacterLimit: Infinity,
    singleQuotes: false,
    transform: (obj, prop, originalResult) => {
      if (typeof obj[prop] === 'function') {
        return 'ƒ'
      }
      return originalResult
    },
  })
}

export function stringifyCss(
  className: string,
  obj: any,
  {
    tabSize = 2,
    showPixelEquivalents = false,
    rootFontSize = 16,
  }: Partial<{
    tabSize: number
    showPixelEquivalents: boolean
    rootFontSize: number
  }> = {}
): string {
  if (obj.__rule !== true && !Array.isArray(obj)) return null

  if (Array.isArray(obj)) {
    const rules = obj
      .map((x) =>
        stringifyCss(className, x, {
          tabSize,
          showPixelEquivalents,
          rootFontSize,
        })
      )
      .filter(Boolean)
    if (rules.length === 0) return null
    return rules.join('\n\n')
  }

  let css = ``
  const indent = ' '.repeat(tabSize)

  const context = dlv(obj, '__context', [])
  const props = Object.keys(removeMeta(obj))
  if (props.length === 0) return null

  for (let i = 0; i < context.length; i++) {
    css += `${indent.repeat(i)}${context[i]} {\n`
  }

  const indentStr = indent.repeat(context.length)
  const decls = props.reduce((acc, curr, i) => {
    const propStr = ensureArray(obj[curr])
      .map((val) => {
        const px = showPixelEquivalents ? remToPx(val, rootFontSize) : undefined
        return `${indentStr + indent}${curr}: ${val}${px ? `/* ${px} */` : ''};`
      })
      .join('\n')
    return `${acc}${i === 0 ? '' : '\n'}${propStr}`
  }, '')
  css += `${indentStr}${augmentClassName(className, obj)} {\n${decls}\n${indentStr}}`

  for (let i = context.length - 1; i >= 0; i--) {
    css += `${indent.repeat(i)}\n}`
  }

  return css
}

function augmentClassName(className: string, obj: any): string {
  const pseudo = obj.__pseudo.join('')
  const scope = obj.__scope ? `${obj.__scope} ` : ''
  return `${scope}.${escapeClassName(className)}${pseudo}`
}