import 'package:item_tracker/database/item_table.dart';
import 'package:sqflite/sqflite.dart';
import 'package:path/path.dart';
import 'package:path_provider/path_provider.dart';

import 'item_category_table.dart';

class DatabaseHelper {
  // 数据库名称
  static final _databaseName = "my_database.db";
  // 数据库版本
  static final _databaseVersion = 1;

  static final DatabaseHelper _instance = DatabaseHelper._internal();
  factory DatabaseHelper() => _instance;
  static Database? _database;

  DatabaseHelper._internal();

  Future<Database> get database async {
    if (_database != null) return _database!;
    return (await _initDatabase());
  }

  // 初始化数据库
  Future<Database> _initDatabase() async {
    // 获取App文档目录
    final directory = await getApplicationDocumentsDirectory();
    final path = join(directory.path, _databaseName);
    print('${path}');
    return await openDatabase(
      path,
      version: _databaseVersion,
      onCreate: _onCreate,
    );
  }

  Future<void> _onCreate(Database db, int version) async {
    await db.execute(createItemTable);
    await db.execute(createItemCategoryTable);
    await db.execute(insertDefaultCategory);
  }
}