// Class creating objects                   "Class Declaration" The Blueprint
// ? means can be null or nothing           "Operators"
// ?? means if null, use this instead      

class TabData {

  // FIELDS for storing data                "Fields"
  // What we will be uding in other parts of the code
  
  String id;
  String title;
  String url;
  String favicon;
  DateTime lastAccessed;
  bool isPinned;
  String type;
  int? visitCount;
  String? folder;   

  // Constructor Declaration                  "Constructor Declaration" The Assembly Line
  TabData({
    // Parameters saved from the data coming in
    // "this." current object
    required this.id,
    required this.title,
    required this.url,
    this.favicon = '',
    DateTime? lastAccessed,
    this.isPinned = false,
    this.type = 'tab',
    this.visitCount,
    this.folder,
  }) 
  // initializer logic, AFTER parameters, BEFORE Constructor
  // ?? IF left is null, use right
  // left side is field, right side is parameter the new saved value
  : lastAccessed = lastAccessed ?? DateTime.now();

  // factory logic before constructor, from json so we don't have to extract later.
  factory TabData.fromJson(Map<String, dynamic> json) => TabData(
    // Extract data pass to regular constructor

        id: json['id'].toString(),
        title: json['title'] ?? 'Untitled',
        url: json['url'] ?? '',
        favicon: json['favicon'] ?? json['favIconUrl'] ?? '',
        lastAccessed: json['lastAccessed'] != null
            ? DateTime.parse(json['lastAccessed'])
            : (json['lastVisitTime'] != null
                ? DateTime.parse(json['lastVisitTime'])
                : (json['dateAdded'] != null
                    ? DateTime.parse(json['dateAdded'])
                    : (json['timestamp'] != null
                        ? DateTime.parse(json['timestamp'])
                        : DateTime.now()))),
        isPinned: json['isPinned'] ?? false,
        type: json['type'] ?? 'tab',
        visitCount: json['visitCount'],
        folder: json['folder'],
      );
}

// Data model single tab, bookmark, or history item.
//
// Blueprint storing browser item information.
//
// Every tab ,bookmark is stored as a TabData object.
//
// Constructor creates new TabData objects.
//
// Favicon defaults to empty string
// 
// isPinned defaults to false.
//
// FromJson factory data browser API into TabData object.
//
// Missing data, default values ??.
//
// Foundation: managing/storing tabs.