using System.Net.Sockets;
using System.Text;
using System.Text.Json;
using Hush.Daemon;

namespace Hush.Cli;

public class SocketClient : IAsyncDisposable
{
    private readonly UnixDomainSocketEndPoint _endPoint;
    private readonly Socket _socket;

    public SocketClient()
    {
        var runtimeDir = Environment.GetEnvironmentVariable("XDG_RUNTIME_DIR");
        var baseDir = string.IsNullOrEmpty(runtimeDir) ? Path.GetTempPath() : runtimeDir;
        var socketPath = Path.Combine(baseDir, "hush.sock");
        
        _endPoint = new UnixDomainSocketEndPoint(socketPath);
        _socket = new Socket(AddressFamily.Unix, SocketType.Stream, ProtocolType.Unspecified);
    }

    public async Task ConnectAsync(TimeSpan timeout)
    {
        var cts = new CancellationTokenSource(timeout);
        await _socket.ConnectAsync(_endPoint, cts.Token);
    }

    public async Task SendCommandAsync(byte command)
    {
        await _socket.SendAsync(new[] { command }, SocketFlags.None);
    }

    public async Task<T?> ReceiveJsonAsync<T>(TimeSpan timeout)
    {
        var cts = new CancellationTokenSource(timeout);
        var buffer = new byte[4096];
        var bytesRead = await _socket.ReceiveAsync(buffer, SocketFlags.None, cts.Token);
        
        if (bytesRead == 0)
            return default;
        
        var json = Encoding.UTF8.GetString(buffer, 0, bytesRead);
        return (T?)JsonSerializer.Deserialize(json, typeof(T), DaemonJsonContext.Default);
    }

    public async Task<string?> ReceiveRawJsonAsync(TimeSpan timeout)
    {
        var cts = new CancellationTokenSource(timeout);
        var buffer = new byte[4096];
        var bytesRead = await _socket.ReceiveAsync(buffer, SocketFlags.None, cts.Token);

        if (bytesRead == 0)
            return null;

        return Encoding.UTF8.GetString(buffer, 0, bytesRead);
    }

    public async ValueTask DisposeAsync()
    {
        _socket.Dispose();
        await ValueTask.CompletedTask;
    }
}