public class MainViewModel : INotifyPropertyChanged
{
    private List<IdRecord> hsiRes = new();
    private HashSet<string> recordedIds = new();

    public ObservableCollection<IdRecord> RecordedIdList { get; set; } = new();

    public event PropertyChangedEventHandler? PropertyChanged;

    private IdRecord? ParseLine(string line)
    {
        if (string.IsNullOrWhiteSpace(line))
        {
            Logger.Log("ParseLine.result", "null (whitespace)");
            return null;
        }

        var parts = line.Split('\t');

        if (parts.Length < 2)
        {
            Logger.Log("ParseLine.result", "null (not enough parts)");
            return null;
        }

        var rec = new IdRecord
        {
            Id = parts[0].Trim(),
            Status = parts[1].Trim()
        };

        return rec;
    }

    private IEnumerable<IdRecord> ParseLines(IEnumerable<string> lines)
    {
        Logger.Log("ParseLines.count", lines.Count());
        foreach (var line in lines)
        {
            var record = ParseLine(line);
            if (record != null)
                yield return record;
        }
    }

    private List<IdRecord> ParseFile(string filePath)
    {
        Logger.Log("ParseFile.filePath", filePath);
        Logger.Log("ParseFile.exists", File.Exists(filePath));

        if (!File.Exists(filePath))
            return new List<IdRecord>();

        var records = ParseLines(File.ReadAllLines(filePath)).ToList();
        Logger.Log("ParseFile.records.Count", records.Count);

        return records;
    }

    public void LoadHSI(string hsiPath)
    {
        Logger.Log("LoadHSI.path", hsiPath);
        hsiRes = ParseFile(hsiPath);
        Logger.Log("LoadHSI.hsiRes.Count", hsiRes.Count);
    }

    public void HandleInput(string inputId)
    {
        Logger.Log("HandleInput.inputId", inputId);

        var match = hsiRes.FirstOrDefault(x =>
            string.Equals(x.Id, inputId.Trim(), StringComparison.OrdinalIgnoreCase));

        Logger.Log("HandleInput.match", match == null ? "null" : $"{match.Id}|{match.Status}");
        Logger.Log("HandleInput.recordedIds.Contains", recordedIds.Contains(inputId));

        if (match != null)
        {
            if (recordedIds.Contains(inputId))
            {
                MessageBox.Show($"Ez az ID már szerepel a listában: {inputId}");
                Logger.Log("HandleInput.action", "MessageBox: már szerepel");
                return;
            }

            recordedIds.Add(inputId);
            Logger.Log("HandleInput.action", $"Added to recordedIds: {inputId}");
            RecordedIdList.Insert(0, match);
            Logger.Log("HandleInput.action", $"Inserted to RecordedIdList: {match.Id}|{match.Status}");
        }
        else
        {
            MessageBox.Show($"Ez az ID nem rendelkezik HSI eredménnyel: {inputId}");
            Logger.Log("HandleInput.action", "MessageBox: nincs HSI eredmény");
        }
    }
}