class EmojiPickerHelper {

  constructor(editor) {
    this.editor = editor;
    this.getSearchCursor = this.getSearchCursor.bind(this);
    this.addEmojiOnSearch = this.addEmojiOnSearch.bind(this);
    this.addEmoji = this.addEmoji.bind(this);
  }

  getSearchCursor() {
    const pattern = /:[^:\s]+/;
    const currentPos = this.editor.getCursor();
    const sc = this.editor.getSearchCursor(pattern, currentPos, { multiline: false });
    return sc;
  }

  // Add emoji when triggered by search
  addEmojiOnSearch(emoji) {
    const currentPos = this.editor.getCursor();
    const sc = this.getSearchCursor();
    if (sc.findPrevious()) {
      sc.replace(emoji.colons, this.editor.getTokenAt(currentPos).string);
      this.editor.focus();
      this.editor.refresh();
    }
  }

  // Add emoji when triggered by click emoji icon on top of editor
  addEmoji(emoji) {
    const currentPos = this.editor.getCursor();
    const doc = this.editor.getDoc();
    doc.replaceRange(emoji.colons, currentPos);
    this.editor.focus();
    this.editor.refresh();
  }

  getEmoji() {
    const cm = this.editor;
    const sc = this.getSearchCursor();
    const currentPos = cm.getCursor();

    if (sc.findPrevious()) {
      const isInputtingEmoji = (currentPos.line === sc.to().line && currentPos.ch === sc.to().ch);
      // current search cursor position
      if (!isInputtingEmoji) {
        return;
      }
      const pos = {
        line: sc.to().line,
        ch: sc.to().ch,
      };
      const currentSearchText = sc.matches(true, pos).match[0];
      const searchValue = currentSearchText.replace(':', '');
      return searchValue;
    }

    return;

  }


}

export default EmojiPickerHelper;