/**
 * Heti add-on v 0.1.0
 * Add right spacing between CJK & ANS characters
 */

import Finder  from 'findandreplacedomtext'

// 正则表达式来自 pangu.js https://github.com/vinta/pangu.js
const CJK = '\u2e80-\u2eff\u2f00-\u2fdf\u3040-\u309f\u30a0-\u30fa\u30fc-\u30ff\u3100-\u312f\u3200-\u32ff\u3400-\u4dbf\u4e00-\u9fff\uf900-\ufaff'
const A = 'A-Za-z\u0370-\u03ff'
const N = '0-9'
const S = '`~!@#\\$%\\^&\\*\\(\\)-_=\\+\\[\\]{}\\\\\\|;:\'",<.>\\/\\?'
const ANS = `${A}${N}${S}`
const HETI_NON_CONTIGUOUS_ELEMENTS = {
  // Block Elements
  address:1, article:1, aside:1, blockquote:1, dd:1, div:1,
  dl:1, fieldset:1, figcaption:1, figure:1, footer:1, form:1, h1:1, h2:1, h3:1,
  h4:1, h5:1, h6:1, header:1, hgroup:1, hr:1, main:1, nav:1, noscript:1, ol:1,
  output:1, p:1, pre:1, section:1, ul:1,
  // Other misc. elements that are not part of continuous inline prose:
  br:1, li: 1, summary: 1, dt:1, details:1, rp:1, rt:1, rtc:1,
  // Media / Source elements:
  script:1, style:1, img:1, video:1, audio:1, canvas:1, svg:1, map:1, object:1,
  // Input elements
  input:1, textarea:1, select:1, option:1, optgroup:1, button:1,
  // Table related elements:
  table:1, tbody:1, thead:1, th:1, tr:1, td:1, caption:1, col:1, tfoot:1, colgroup:1
}
const HETI_SKIPPED_ELEMENTS = {
  br:1, hr:1,
  // Media / Source elements:
  script:1, style:1, img:1, video:1, audio:1, canvas:1, svg:1, map:1, object:1,
  // Input elements:
  input:1, textarea:1, select:1, option:1, optgroup: 1, button:1,
  // Pre elements:
  pre: 1, code: 1, sup: 1, sub: 1,
  // Heti elements
  'heti-spacing': 1,
}
const HETI_SKIPPED_CLASS = 'heti-skip'
const hasOwn = {}.hasOwnProperty

class Heti {
  constructor(rootSelector) {
    this.rootSelector = rootSelector || '.heti'
    this.REG_FULL = new RegExp(`(?<=[${CJK}])( *[${ANS}]+(?: +[${ANS}]+)* *)(?=[${CJK}])`, 'g')
    this.REG_START = new RegExp(`([${ANS}]+(?: +[${ANS}]+)* *)(?=[${CJK}])`, 'g')
    this.REG_END = new RegExp(`(?<=[${CJK}])( *[${ANS}]+(?: +[${ANS}]+)*)`, 'g')
    this.funcForceContext = function forceContext(el) {
      return hasOwn.call(HETI_NON_CONTIGUOUS_ELEMENTS, el.nodeName.toLowerCase())
    }
    this.funcFilterElements = function filterElements(el) {
      return (
        !(el.classList && el.classList.contains(HETI_SKIPPED_CLASS)) &&
        !hasOwn.call(HETI_SKIPPED_ELEMENTS, el.nodeName.toLowerCase())
      )
    }
  }

  spacingElements(elmList) {
    for (let $$root of elmList) {
      this.spacingElement($$root)
    }
  }

  spacingElement($$elm) {
    const commonConfig = {
      forceContext: this.funcForceContext,
      filterElements: this.funcFilterElements
    }
    const getWrapper = function (classList, text) {
      const $$r = document.createElement('heti-spacing')
      $$r.className = classList
      $$r.textContent = text.trim()
      return $$r
    }

    Finder($$elm, Object.assign(commonConfig, {
      find: this.REG_FULL,
      replace: portion => getWrapper('heti-spacing-start heti-spacing-end', portion.text)
    }))

    Finder($$elm, Object.assign(commonConfig, {
      find: this.REG_START,
      replace: portion => getWrapper('heti-spacing-start', portion.text)
    }))

    Finder($$elm, Object.assign(commonConfig, {
      find: this.REG_END,
      replace: portion => getWrapper('heti-spacing-end', portion.text)
    }))
  }

  autoSpacing() {
    document.addEventListener('DOMContentLoaded', () => {
      const $$rootList = document.querySelectorAll(this.rootSelector)

      for (let $$root of $$rootList) {
        this.spacingElement($$root)
      }
    })
  }
}

export default Heti