sp-editor/packages/editor/src/helpers.ts

SpEditor is a HTML5 rich text editor in smartphone browsers

/**
 * Created by Capricorncd.
 * https://github.com/capricorncd
 * Date: 2022/05/05 10:55:25 (GMT+0900)
 */
import { slice } from 'zx-sml'

/**
 * replaceHtmlTag
 * @param input `string`
 * @param oldNodeName `string`
 * @param newNodeName `string`
 * @returns `string`
 */
export function replaceHtmlTag(input: string, oldNodeName: string, newNodeName: string): string {
  return input.replace(new RegExp('(^<' + oldNodeName + ')|(' + oldNodeName + '>$)', 'gi'), (match) =>
    match.replace(new RegExp(oldNodeName, 'i'), newNodeName.toLowerCase()),
  )
}

/**
 * remove li tag
 * @param input
 * @returns
 */
export function removeLiTags(input: string): string {
  return input.replace(/<li[^>]*>(.+)<\/li>/gi, '$1')
}

export function isUlElement(el: Element | string): boolean {
  const nodeName = typeof el === 'string' ? el : el.nodeName
  return /^UL|OL$/i.test(nodeName)
}

/**
 * only one BR Node in the el's children
 * <anyTag><br></anyTag>
 * @param el
 */
export function isOnlyBrInChildren(el: HTMLElement | Element | null): boolean {
  if (!el) return false
  const nodes = slice<Node, NodeList>(el.childNodes)
  return nodes.length > 0 && nodes.every((node) => node.nodeName === 'BR')
}

/**
 * isPairedTags(el)
 * Determine if `el` is a paired tags.
 * @param el `Element | string` Element or HTML string.
 * @returns `boolean`
 */
export function isPairedTags<T extends Element>(el: T | string): boolean {
  if (typeof el !== 'string' && el.nodeName) {
    el = el.outerHTML
  }
  return typeof el === 'string' && /^<(\w+)[^>]*>.*<\/\1>$/.test(el.replace(/\n/g, ''))
}

/**
 * isSpecialPairedTags(el)
 * Determine whether `el` is PICTURE, VIDEO, AUDIO and other HTML tags.
 * @param el `Element`
 * @returns `boolean`
 */
export function isSpecialPairedTags<T extends Element>(el: T): boolean {
  return ['PICTURE', 'VIDEO', 'AUDIO', 'CANVAS'].includes(el.nodeName)
}

export function isSpecialTags<T extends Element>(el: T): boolean {
  return ['IMG'].includes(el.nodeName) || isSpecialPairedTags(el)
}

/**
 * hasSpecialTag(el)
 * @param el `Element`
 * @returns
 */
export function hasSpecialTag<T extends Element>(el: T): boolean {
  if (isSpecialTags(el)) return true
  for (let i = 0; i < el.children.length; i++) {
    if (hasSpecialTag(el.children[i])) return true
  }
  return false
}