markdown.dart

class Section {
  int level;
  Element titleNode;
  List<Node> contentNodes;
  List<Section> subSections;

  void _addContentNodes(Node nodes) {
    contentNodes = List.from(contentNodes)..add(nodes);
  }

  Section({this.level, this.titleNode, this.contentNodes}) {
    contentNodes = [];
    subSections = [];
  }
}

class SectionMaker {
  var path = 'markdown file path';
  Section _parentSection;
  Section _currentParentSection;
  Section _currentSection;
  var level = 0;
  SectionMaker();

  List<Node> _getNodes(String filePath) {
    var file = io.File(filePath);
    var document = Document();
    var markdown = file.readAsStringSync();
    var lines = markdown.replaceAll('\r\n', '\n').split('\n');
    return document.parseLines(lines);
  }

  Section _makeSection({int level, Node titleNode}) {
    return Section(level: level, titleNode: titleNode);
  }

  Section generateSection() {
    var nodes = _getNodes(path);
    nodes.forEach((element) {
      if (element is Element) {
        if (element.tag == 'h1') {
          _parentSection ??= _makeSection(level: -1);

          _currentParentSection =
              _makeSection(level: level, titleNode: element);
          _currentSection = _currentParentSection;
          level++;
          _parentSection.subSections.add(_currentParentSection);
        }
        if (element.tag == 'h2') {
          _currentSection = _makeSection(titleNode: element);
          _currentParentSection.subSections.add(_currentSection);
        }
        _currentSection._addContentNodes(element);
      } else {
        _currentSection._addContentNodes(element);
      }
    });
    return _parentSection;
  }
}