PIbd-22_Katysheva_N.E._Pizz.../Pizzeria/PizzeriaFileImplement/DataFileSingleton.cs

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2024-03-12 23:45:49 +04:00
using PizzeriaFileImplement.Models;
using System.Xml.Linq;
namespace PizzeriaFileImplement
{
public class DataFileSingleton
{
private static DataFileSingleton? instance;
private readonly string ComponentFileName = "Component.xml";
private readonly string OrderFileName = "Order.xml";
private readonly string PizzaFileName = "Pizza.xml";
public List<Component> Components { get; private set; }
public List<Order> Orders { get; private set; }
public List<Pizza> Pizzas { get; private set; }
private DataFileSingleton()
{
Components = LoadData(ComponentFileName, "Component", x => Component.Create(x)!)!;
Pizzas = LoadData(PizzaFileName, "Pizza", x => Pizza.Create(x)!)!;
Orders = LoadData(OrderFileName, "Order", x => Order.Create(x)!)!;
}
public static DataFileSingleton GetInstance()
{
if (instance == null)
{
instance = new DataFileSingleton();
}
return instance;
}
public void SaveComponents() => SaveData(Components, ComponentFileName,"Components", x => x.GetXElement);
public void SavePizzas() => SaveData(Pizzas, PizzaFileName, "Pizzas", x => x.GetXElement);
public void SaveOrders() => SaveData(Orders, OrderFileName, "Orders", x => x.GetXElement);
private static List<T>? LoadData<T>(string filename, string xmlNodeName,Func<XElement, T> selectFunction)
{
if (File.Exists(filename))
{
return XDocument.Load(filename)?.Root?.Elements(xmlNodeName)?.Select(selectFunction)?.ToList();
}
return new List<T>();
}
private static void SaveData<T>(List<T> data, string filename, string xmlNodeName, Func<T, XElement> selectFunction)
{
if (data != null)
{
new XDocument(new XElement(xmlNodeName, data.Select(selectFunction).ToArray())).Save(filename);
}
}
}
}