using System.Collections;
using System.Text.Json;

namespace Repository;

public class Repository : IRepository
{
    private const string _appName = "Keychain";
    private readonly string _filePath;
    private List<object>? _cache;
    private bool _cacheDirty = true;

    public Repository(string fileName)
    {
        var xdgDataHome = Environment.GetEnvironmentVariable("XDG_DATA_HOME");
        string dataHome;
        if (!string.IsNullOrEmpty(xdgDataHome))
        {
            dataHome = Path.Combine(xdgDataHome, _appName);
        }
        else
        {
            dataHome = Path.Combine(
                Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.UserProfile), ".local", "share"),
                _appName
            );
        }
        _filePath = Path.Combine(dataHome, fileName);
    }

    public IEnumerable ReadAll()
    {
        if (!_cacheDirty && _cache != null)
            return _cache;

        if (!File.Exists(_filePath))
        {
            _cache = new List<object>();
        }
        else
        {
            var json = File.ReadAllText(_filePath);
            _cache = JsonSerializer.Deserialize<List<object>>(json) ?? new List<object>();
        }
        _cacheDirty = false;
        return _cache;
    }

    public object Get(uint id)
    {
        
    }

    public void WriteAll(IEnumerable items)
    {
        var json = JsonSerializer.Serialize(items);
        var directory = Path.GetDirectoryName(_filePath);
        if (!Directory.Exists(directory))
        {
            Directory.CreateDirectory(directory!);
        }
        File.WriteAllText(_filePath, json);

        _cache = (List<object>)items;
        _cacheDirty = false;
    }
}