Glue layer

[scalablecory]

A layer is needed to combine:

• Instantiating a sensor -> theme -> display graph based on configuration.
• Hosting a Control API and managing when it changes config.
• Hosting a BLE Control API that forwards to the Control API.

This will functionally replace the hard-coded implementation:

aether/src/Aether/Program.cs

Lines 16 to 57 in b936a31

	// TODO: this needs to be replaced by something that reads config, resolves dependencies, etc.
	var runDeviceCommand = new Command("run-device", "Runs an Aether device");
	runDeviceCommand.Handler = CommandHandler.Create(async () =>
	{
	// Initialize MS5637.
	using I2cDevice ms5637Device = I2cDevice.Create(new I2cConnectionSettings(1, ObservableMs5637.DefaultAddress));
	await using ObservableSensor ms5637Driver = ObservableMs5637.OpenSensor(ms5637Device, dependencies: Observable.Empty<Measurement>());
	// Initialize SCD4x, taking a dependency on MS5637 for calibration with barometric pressure.
	using I2cDevice scd4xDevice = I2cDevice.Create(new I2cConnectionSettings(1, ObservableScd4x.DefaultAddress));
	await using ObservableSensor scdDriver = ObservableScd4x.OpenSensor(scd4xDevice, dependencies: ms5637Driver);
	// All the measurements funnel through here.
	// Multiple sensors can support the same measures. In this case, both devices support teperature. To prevent inconsistencies, only use one.
	IObservable<Measurement> measurements = Observable.Merge(
	ms5637Driver.Where(x => x.Measure == Measure.BarometricPressure),
	scdDriver
	);
	// Initialize display.
	var spiConfig = new System.Device.Spi.SpiConnectionSettings(0, 0)
	{
	ClockFrequency = 10000000
	};
	using var gpio = new GpioController(PinNumberingScheme.Logical);
	using SpiDevice displayDevice = SpiDevice.Create(spiConfig);
	using var displayDriver = new WaveshareEPD2_9inV2(displayDevice, gpio, dcPinId: 25, rstPinId: 17, busyPinId: 24);
	// Initialize the theme, which takes all the measurements and renders them to a display.
	var lines = new[] { Measure.CO2, Measure.Humidity, Measure.BarometricPressure, Measure.Temperature };
	using IDisposable theme = MultiLineTheme.CreateTheme(displayDriver, lines, measurements);
	// Wait for Ctrl+C to exit.
	var tcs = new TaskCompletionSource();
	Console.CancelKeyPress += (s, e) =>
	{
	Console.WriteLine("Closing...");
	e.Cancel = true;
	tcs.TrySetResult();
	};
	await tcs.Task;
	});

[scalablecory]

Here's a general architectural outline to help plan this: