/**
 * TODO: These methods can probably be combined somehow
 * Parse HTML tags & HTML Characters
 */

export default class HTMLParser {
  /**
   * Type HTML tags & HTML Characters
   * @param {string} curString Current string
   * @param {number} curStrPos Position in current string
   * @param {Typed} self instance of Typed
   * @returns {number} a new string position
   * @private
   */

  typeHtmlChars(curString, curStrPos, self) {
    if (self.contentType !== 'html') return curStrPos;
    const curChar = curString.substr(curStrPos).charAt(0);
    if (curChar === '<' || curChar === '&') {
      let endTag = '';
      if (curChar === '<') {
        endTag = '>';
      } else {
        endTag = ';';
      }
      while (curString.substr(curStrPos + 1).charAt(0) !== endTag) {
        curStrPos++;
        if (curStrPos + 1 > curString.length) {
          break;
        }
      }
      curStrPos++;
    }
    return curStrPos;
  }

  /**
   * Backspace HTML tags and HTML Characters
   * @param {string} curString Current string
   * @param {number} curStrPos Position in current string
   * @param {Typed} self instance of Typed
   * @returns {number} a new string position
   * @private
   */
  backSpaceHtmlChars(curString, curStrPos, self) {
    if (self.contentType !== 'html') return curStrPos;
    const curChar = curString.substr(curStrPos).charAt(0);
    if (curChar === '>' || curChar === ';') {
      let endTag = '';
      if (curChar === '>') {
        endTag = '<';
      } else {
        endTag = '&';
      }
      while (curString.substr(curStrPos - 1).charAt(0) !== endTag) {
        curStrPos--;
        if (curStrPos < 0) {
          break;
        }
      }
      curStrPos--;
    }
    return curStrPos;
  }
}

export let htmlParser = new HTMLParser();
