import 'dart:async';

import 'package:flutter_test/flutter_test.dart';
import 'package:nomadcode_app/src/integrations/proto_socket/proto_socket_client.dart';
import 'package:nomadcode_app/src/integrations/proto_socket/proto_socket_envelope.dart';
import 'package:nomadcode_app/src/integrations/proto_socket/proto_socket_endpoint_config.dart';
import 'package:nomadcode_app/src/integrations/proto_socket/proto_socket_lifecycle.dart';
import 'package:protobuf/well_known_types/google/protobuf/struct.pb.dart';

class _FakeTransport implements ProtoSocketTransport {
  final StreamController<ProtoSocketEnvelope> controller =
      StreamController<ProtoSocketEnvelope>.broadcast();
  int sendCalls = 0;
  int closeCalls = 0;
  ProtoSocketEnvelope? response;

  @override
  Stream<ProtoSocketEnvelope> get events => controller.stream;

  @override
  Future<ProtoSocketEnvelope> sendRequest(
    ProtoSocketEnvelope envelope, {
    Duration timeout = const Duration(seconds: 30),
  }) async {
    sendCalls += 1;
    return response ?? envelope;
  }

  @override
  Future<void> close() async {
    closeCalls += 1;
    await controller.close();
  }
}

class _FakeConnector implements ProtoSocketConnector {
  int connectCalls = 0;
  int disconnectCalls = 0;
  Object? throwOnConnect;
  _FakeTransport transport = _FakeTransport();

  @override
  Future<ProtoSocketTransport> connect(ProtoSocketEndpointConfig config) async {
    connectCalls += 1;
    final err = throwOnConnect;
    if (err != null) throw err;
    return transport;
  }

  @override
  Future<void> disconnect() async {
    disconnectCalls += 1;
  }
}

class _FakePeer implements NomadProtoSocketPeer {
  final StreamController<ProtoSocketEnvelope> controller =
      StreamController<ProtoSocketEnvelope>.broadcast();
  ProtoSocketEnvelope? lastRequest;
  Duration? lastTimeout;
  int closeCalls = 0;

  @override
  Stream<ProtoSocketEnvelope> get envelopeEvents => controller.stream;

  @override
  Future<ProtoSocketEnvelope> sendEnvelopeRequest(
    ProtoSocketEnvelope envelope, {
    Duration timeout = const Duration(seconds: 30),
  }) async {
    lastRequest = envelope;
    lastTimeout = timeout;
    return ProtoSocketEnvelope(
      id: envelope.id,
      correlationId: envelope.correlationId,
      type: 'response',
      channel: envelope.channel,
      action: envelope.action,
      payload: const {'ok': true},
    );
  }

  @override
  Future<void> close() async {
    closeCalls += 1;
    await controller.close();
  }
}

void main() {
  const config = ProtoSocketEndpointConfig(
    host: 'core.example.com',
    port: 443,
    secure: true,
  );

  test('happy path emits connecting -> connected -> disconnected', () async {
    final fake = _FakeConnector();
    final lifecycle = ProtoSocketLifecycle(connector: fake);
    final states = <ProtoSocketConnectionState>[];
    final sub = lifecycle.stateStream.listen(states.add);

    expect(lifecycle.state, ProtoSocketConnectionState.disconnected);

    await lifecycle.connect(config);
    expect(lifecycle.state, ProtoSocketConnectionState.connected);
    expect(lifecycle.transport, same(fake.transport));
    expect(fake.connectCalls, equals(1));

    await lifecycle.disconnect();
    expect(lifecycle.state, ProtoSocketConnectionState.disconnected);
    expect(lifecycle.transport, isNull);
    expect(fake.disconnectCalls, equals(1));

    await Future<void>.delayed(Duration.zero);
    await sub.cancel();
    await lifecycle.dispose();

    expect(states, [
      ProtoSocketConnectionState.connecting,
      ProtoSocketConnectionState.connected,
      ProtoSocketConnectionState.disconnected,
    ]);
  });

  test('connect failure transitions to failed and records error', () async {
    final fake = _FakeConnector()..throwOnConnect = StateError('boom');
    final lifecycle = ProtoSocketLifecycle(connector: fake);

    await expectLater(lifecycle.connect(config), throwsA(isA<StateError>()));
    expect(lifecycle.state, ProtoSocketConnectionState.failed);
    expect(lifecycle.lastError, isA<StateError>());
    expect(lifecycle.transport, isNull);

    await lifecycle.dispose();
  });

  test('connect is a no-op when already connecting or connected', () async {
    final fake = _FakeConnector();
    final lifecycle = ProtoSocketLifecycle(connector: fake);

    await lifecycle.connect(config);
    await lifecycle.connect(config);

    expect(fake.connectCalls, equals(1));
    await lifecycle.dispose();
  });

  test('disconnect from disconnected state is a no-op', () async {
    final fake = _FakeConnector();
    final lifecycle = ProtoSocketLifecycle(connector: fake);

    await lifecycle.disconnect();
    expect(fake.disconnectCalls, equals(0));
    expect(lifecycle.state, ProtoSocketConnectionState.disconnected);

    await lifecycle.dispose();
  });

  test(
    'RealProtoSocketConnector uses injected factories without sockets',
    () async {
      final fakeSocket = Object();
      final fakeTransport = _FakeTransport();
      ProtoSocketEndpointConfig? seenConfig;
      Object? seenSocket;
      final connector = RealProtoSocketConnector(
        socketFactory: (config) async {
          seenConfig = config;
          return fakeSocket;
        },
        transportFactory: (socket, config) {
          seenSocket = socket;
          expect(config, same(seenConfig));
          return fakeTransport;
        },
      );

      final transport = await connector.connect(config);
      expect(seenConfig, same(config));
      expect(seenSocket, same(fakeSocket));
      expect(transport, same(fakeTransport));

      await connector.disconnect();
      expect(fakeTransport.closeCalls, equals(1));
    },
  );

  test('Struct parser map supports short and qualified names', () {
    final parsers = protoSocketStructParserMap();
    final qualifiedName = Struct.getDefault().info_.qualifiedMessageName;
    final struct = ProtoSocketEnvelope(
      id: 'msg-1',
      type: 'event',
      channel: 'task',
      action: 'task.status.changed',
      payload: const {'id': 'task-1'},
    ).toStruct();

    expect(parsers[(Struct).toString()], isNotNull);
    expect(parsers[qualifiedName], isNotNull);
    expect(
      parsers[(Struct).toString()]!(struct.writeToBuffer()),
      isA<Struct>(),
    );
    expect(parsers[qualifiedName]!(struct.writeToBuffer()), isA<Struct>());
  });

  test('ProtoSocketClientTransport delegates requests and close', () async {
    final peer = _FakePeer();
    final transport = ProtoSocketClientTransport(peer);
    const request = ProtoSocketEnvelope(
      id: 'req-1',
      type: 'request',
      channel: 'task',
      action: 'task.list',
    );

    final response = await transport.sendRequest(
      request,
      timeout: const Duration(seconds: 5),
    );

    expect(peer.lastRequest, same(request));
    expect(peer.lastTimeout, equals(const Duration(seconds: 5)));
    expect(response.type, equals('response'));
    expect(response.payload, equals({'ok': true}));

    await transport.close();
    expect(peer.closeCalls, equals(1));
  });
}