[ApiController]
[Route("api/[controller]")]
public class TanksController : ControllerBase
{
    private readonly ITankService _tankService;

    public TanksController(ITankService tankService)
    {
        _tankService = tankService;
    }

    [HttpGet]
    public async Task<ActionResult<IEnumerable<Tank>>> GetAll(CancellationToken ct)
    {
        var tanks = await _tankService.GetAllTanksAsync(ct);
        return Ok(tanks);
    }

    [HttpPost("{id}/state")]
    public async Task<IActionResult> SetState(Guid id, [FromBody] object state, CancellationToken ct)
    {
        await _tankService.UpdateTankAsync(id, state, ct);
        return NoContent();
    }
}

// Program.cs - Register as singletons (VanDaemon pattern)
builder.Services.AddSingleton<ITankService, TankService>();
builder.Services.AddSingleton<IControlService, ControlService>();
builder.Services.AddSingleton<JsonFileStore>();

// SignalR
builder.Services.AddSignalR();

// After app.Build()
app.MapHub<TelemetryHub>("/hubs/telemetry");

public class TelemetryBackgroundService : BackgroundService
{
    private readonly IServiceProvider _provider;

    protected override async Task ExecuteAsync(CancellationToken ct)
    {
        while (!ct.IsCancellationRequested)
        {
            using var scope = _provider.CreateScope();
            var tankService = scope.ServiceProvider.GetRequiredService<ITankService>();
            await tankService.RefreshAllAsync(ct);
            await Task.Delay(TimeSpan.FromSeconds(5), ct);
        }
    }
}

app.MapGet("/health", () => Results.Ok(new
{
    status = "healthy",
    timestamp = DateTime.UtcNow
}));