import 'dart:async';

import 'package:iperf3gui/domain/models/iperf3_event.dart';
import 'package:iperf3gui/domain/models/iperf3_result.dart';
import 'package:iperf3gui/domain/models/test_configuration.dart';
import 'package:iperf3gui/domain/services/iperf3_runner.dart';

/// In-memory [Iperf3Runner] for tests.
///
/// Implements the interface rather than the concrete service, so it tracks the
/// five members the UI actually depends on instead of every public member the
/// MethodChannel implementation happens to have.
class FakeIperf3Runner implements Iperf3Runner {
  FakeIperf3Runner({this.onRun});

  /// Supplies the result for each [run], and may [emit] events first.
  Future<Iperf3Result> Function(TestConfiguration)? onRun;

  final StreamController<Iperf3Event> _controller =
      StreamController<Iperf3Event>.broadcast();

  /// Configurations passed to [run], in order.
  final List<TestConfiguration> runCalls = [];

  int stopCallCount = 0;
  bool disposed = false;
  bool _isRunning = false;

  int get runCallCount => runCalls.length;

  /// Push an event as if the native layer had reported it.
  void emit(Iperf3Event event) => _controller.add(event);

  @override
  Stream<Iperf3Event> get events => _controller.stream;

  @override
  bool get isRunning => _isRunning;

  @override
  Future<Iperf3Result> run(TestConfiguration config) async {
    runCalls.add(config);
    _isRunning = true;
    try {
      if (onRun != null) return await onRun!(config);
      return const Iperf3Result(rawOutput: '', exitCode: 0);
    } finally {
      _isRunning = false;
    }
  }

  @override
  Future<void> stop() async {
    stopCallCount++;
  }

  @override
  Future<void> dispose() async {
    disposed = true;
    await _controller.close();
  }
}