/// interface for every Terminal backend
abstract class TerminalBackend {
  /// initializes the backend
  /// This can be used to instantiate instances that are problematic when
  /// passed to a Isolate.
  /// The [TerminalIsolate] will pass the backend to the [Terminal] that then
  /// executes [init] from inside the Isolate.
  /// So when your backend needs any complex instances (most of them will)
  /// then strongly consider instantiating them here
  void init();

  /// Stream for data that gets read from the backend
  Stream<String> get out;

  /// Future that fires when the backend terminates
  Future<int> get exitCode;

  /// writes data to this backend
  void write(String input);

  /// notifies the backend about a view port resize that happened
  void resize(int width, int height, int pixelWidth, int pixelHeight);

  /// terminates this backend
  void terminate();

  /// acknowledges processing of a data junk
  void ackProcessed();
}