PiperFeladat/Repository/JsonRepository.cs

using System.Text.Json;
using Models;

namespace Repository;

public class JsonRepository : IRepository
{
    private const string _fileName = "data.json";

    public User? Read()
    {
        if (File.Exists(_fileName))
        {
            try
            {
                string json = File.ReadAllText(_fileName);
                return JsonSerializer.Deserialize<User>(json) ?? new User("fallback", "fallback", "fallback");
            }
            catch (JsonException e)
            {
                WriteToStdErr($"JSON error: {e.Message}");
            }
            catch (IOException e)
            {
                WriteToStdErr($"File I/O error: {e.Message}");
            }
            catch (Exception e)
            {
                WriteToStdErr($"Unexpected error: {e.Message}");
            }
        }
        return null;
    }

    public int Write(User item)
    {
        try
        {
            string json = JsonSerializer.Serialize(item);
            File.WriteAllText(_fileName, json);
            return 0;
        }
        catch (JsonException e)
        {
            WriteToStdErr($"JSON error: {e.Message}");
            return e.GetHashCode();
        }
        catch (IOException e)
        {
            WriteToStdErr($"File I/O error: {e.Message}");
            return e.GetHashCode();
        }
        catch (Exception e)
        {
            WriteToStdErr($"Unexpected error: {e.Message}");
            return e.GetHashCode();
        }
    }

    private void WriteToStdErr(string message)
    {
        using var sw = new StreamWriter(Console.OpenStandardError());
        sw.WriteLine(message);
    }
}