import 'dart:async';
import 'dart:convert';
import 'dart:developer' as developer;
import 'dart:io';
import 'package:flutter/foundation.dart';
import 'package:hooks_riverpod/hooks_riverpod.dart';
import 'package:island/pods/network.dart';
import 'package:shelf/shelf.dart';
import 'package:shelf/shelf_io.dart' as shelf_io;
import 'package:shelf_web_socket/shelf_web_socket.dart';
import 'package:web_socket_channel/web_socket_channel.dart';

// Conditional imports for IPC server - use web stubs on web platform
import 'ipc_server.dart' if (dart.library.html) 'ipc_server.web.dart';

const String kRpcLogPrefix = 'arRPC.websocket';
const String kRpcIpcLogPrefix = 'arRPC.ipc';

// IPC Constants
const String kIpcBasePath = 'discord-ipc';

// IPC Packet Types
class IpcTypes {
  static const int handshake = 0;
  static const int frame = 1;
  static const int close = 2;
  static const int ping = 3;
  static const int pong = 4;
}

// IPC Close Codes
class IpcCloseCodes {
  static const int closeNormal = 1000;
  static const int closeUnsupported = 1003;
  static const int closeAbnormal = 1006;
}

// IPC Error Codes
class IpcErrorCodes {
  static const int invalidClientId = 4000;
  static const int invalidOrigin = 4001;
  static const int rateLimited = 4002;
  static const int tokenRevoked = 4003;
  static const int invalidVersion = 4004;
  static const int invalidEncoding = 4005;
}

// Reference https://github.com/OpenAsar/arrpc/blob/main/src/transports/ipc.js
class ActivityRpcServer {
  static const List<int> portRange = [6463, 6472]; // Ports 6463–6472
  Map<String, Function>
  handlers; // {connection: (socket), message: (socket, data), close: (socket)}
  HttpServer? _httpServer;
  IpcServer? _ipcServer;
  final List<WebSocketChannel> _wsSockets = [];

  ActivityRpcServer(this.handlers);

  void updateHandlers(Map<String, Function> newHandlers) {
    handlers = newHandlers;
  }

  // Start the server
  Future<void> start() async {
    int port = portRange[0];
    bool wsSuccess = false;

    // Start WebSocket server
    while (port <= portRange[1]) {
      developer.log('Trying port $port', name: kRpcLogPrefix);
      try {
        _httpServer = await HttpServer.bind(InternetAddress.loopbackIPv4, port);
        developer.log('Listening on $port', name: kRpcLogPrefix);

        shelf_io.serveRequests(_httpServer!, (Request request) async {
          developer.log('New request', name: kRpcLogPrefix);
          if (request.headers['upgrade']?.toLowerCase() == 'websocket') {
            final handler = webSocketHandler((WebSocketChannel channel, _) {
              _wsSockets.add(channel);
              _onWsConnection(channel, request);
            });
            return handler(request);
          }
          developer.log(
            'New request disposed due to not websocket',
            name: kRpcLogPrefix,
          );
          return Response.notFound('Not a WebSocket request');
        });
        wsSuccess = true;
        break;
      } catch (e) {
        if (e is SocketException && e.osError?.errorCode == 98) {
          developer.log('$port in use!', name: kRpcLogPrefix);
        } else {
          developer.log('HTTP error: $e', name: kRpcLogPrefix);
        }
        port++;
        await Future.delayed(Duration(milliseconds: 100)); // Add delay
      }
    }

    if (!wsSuccess) {
      throw Exception(
        'Failed to bind to any port in range ${portRange[0]}–${portRange[1]}',
      );
    }

    // Start IPC server
    final shouldStartIpc = !Platform.isMacOS && !kIsWeb;
    if (shouldStartIpc) {
      try {
        _ipcServer = MultiPlatformIpcServer();

        // Set up IPC handlers
        _ipcServer!.handlePacket = (socket, packet, _) {
          _handleIpcPacket(socket, packet);
        };

        await _ipcServer!.start();
      } catch (e) {
        developer.log('IPC server error: $e', name: kRpcIpcLogPrefix);
      }
    } else {
      developer.log(
        'IPC server disabled on macOS or web in production mode',
        name: kRpcIpcLogPrefix,
      );
    }
  }

  // Stop the server
  Future<void> stop() async {
    // Stop WebSocket server
    for (var socket in _wsSockets) {
      try {
        await socket.sink.close();
      } catch (e) {
        developer.log('Error closing WebSocket: $e', name: kRpcLogPrefix);
      }
    }
    _wsSockets.clear();
    await _httpServer?.close(force: true);

    // Stop IPC server
    await _ipcServer?.stop();

    developer.log('Servers stopped', name: kRpcLogPrefix);
  }

  // Handle new WebSocket connection
  void _onWsConnection(WebSocketChannel socket, Request request) {
    final uri = request.url;
    final params = uri.queryParameters;
    final ver = int.tryParse(params['v'] ?? '1') ?? 1;
    final encoding = params['encoding'] ?? 'json';
    final clientId = params['client_id'] ?? '';
    final origin = request.headers['origin'] ?? '';

    developer.log(
      'New WS connection! origin: $origin, params: $params',
      name: kRpcLogPrefix,
    );

    if (origin.isNotEmpty &&
        ![
          'https://discord.com',
          'https://ptb.discord.com',
          'https://canary.discord.com',
        ].contains(origin)) {
      developer.log('Disallowed origin: $origin', name: kRpcLogPrefix);
      socket.sink.close();
      return;
    }

    if (encoding != 'json') {
      developer.log(
        'Unsupported encoding requested: $encoding',
        name: kRpcLogPrefix,
      );
      socket.sink.close();
      return;
    }

    if (ver != 1) {
      developer.log('Unsupported version requested: $ver', name: kRpcLogPrefix);
      socket.sink.close();
      return;
    }

    final socketWithMeta = _WsSocketWrapper(socket, clientId, encoding);

    socket.stream.listen(
      (data) => _onWsMessage(socketWithMeta, data),
      onError: (e) {
        developer.log('WS socket error: $e', name: kRpcLogPrefix);
      },
      onDone: () {
        developer.log('WS socket closed', name: kRpcLogPrefix);
        handlers['close']?.call(socketWithMeta);
        _wsSockets.remove(socket);
      },
    );

    handlers['connection']?.call(socketWithMeta);
  }

  // Handle incoming WebSocket message
  Future<void> _onWsMessage(_WsSocketWrapper socket, dynamic data) async {
    if (data is! String) {
      developer.log(
        'Invalid WebSocket message: not a string',
        name: kRpcLogPrefix,
      );
      return;
    }
    try {
      final jsonData = await compute(jsonDecode, data);
      if (jsonData is! Map<String, dynamic>) {
        developer.log(
          'Invalid WebSocket message: not a JSON object',
          name: kRpcLogPrefix,
        );
        return;
      }
      developer.log('WS message: $jsonData', name: kRpcLogPrefix);
      handlers['message']?.call(socket, jsonData);
    } catch (e) {
      developer.log('WS message parse error: $e', name: kRpcLogPrefix);
    }
  }

  // Handle IPC packet
  void _handleIpcPacket(IpcSocketWrapper socket, IpcPacket packet) {
    switch (packet.type) {
      case IpcTypes.ping:
        developer.log('IPC ping received', name: kRpcIpcLogPrefix);
        socket.sendPong(packet.data);
        break;

      case IpcTypes.pong:
        developer.log('IPC pong received', name: kRpcIpcLogPrefix);
        break;

      case IpcTypes.handshake:
        if (socket.handshook) {
          throw Exception('Already handshook');
        }
        socket.handshook = true;
        _onIpcHandshake(socket, packet.data);
        break;

      case IpcTypes.frame:
        if (!socket.handshook) {
          throw Exception('Need to handshake first');
        }
        developer.log('IPC frame: ${packet.data}', name: kRpcIpcLogPrefix);
        handlers['message']?.call(socket, packet.data);
        break;

      case IpcTypes.close:
        socket.close();
        break;

      default:
        throw Exception('Invalid packet type: ${packet.type}');
    }
  }

  // Handle IPC handshake
  void _onIpcHandshake(IpcSocketWrapper socket, Map<String, dynamic> params) {
    developer.log('IPC handshake: $params', name: kRpcIpcLogPrefix);

    final ver = int.tryParse(params['v']?.toString() ?? '1') ?? 1;
    final clientId = params['client_id']?.toString() ?? '';

    if (ver != 1) {
      developer.log(
        'IPC unsupported version requested: $ver',
        name: kRpcIpcLogPrefix,
      );
      socket.closeWithCode(IpcErrorCodes.invalidVersion);
      return;
    }

    if (clientId.isEmpty) {
      developer.log('IPC client ID required', name: kRpcIpcLogPrefix);
      socket.closeWithCode(IpcErrorCodes.invalidClientId);
      return;
    }

    socket.clientId = clientId;

    handlers['connection']?.call(socket);
  }
}

// WebSocket wrapper
class _WsSocketWrapper {
  final WebSocketChannel channel;
  final String clientId;
  final String encoding;

  _WsSocketWrapper(this.channel, this.clientId, this.encoding);

  void send(Map<String, dynamic> msg) {
    developer.log('WS sending: $msg', name: kRpcLogPrefix);
    channel.sink.add(jsonEncode(msg));
  }
}

// State management for server status and activities
class ServerState {
  final String status;
  final List<String> activities;

  ServerState({required this.status, this.activities = const []});

  ServerState copyWith({String? status, List<String>? activities}) {
    return ServerState(
      status: status ?? this.status,
      activities: activities ?? this.activities,
    );
  }
}

class ServerStateNotifier extends StateNotifier<ServerState> {
  final ActivityRpcServer server;

  ServerStateNotifier(this.server)
    : super(ServerState(status: 'Server not started'));

  Future<void> start() async {
    if (!Platform.isAndroid && !Platform.isIOS && !kIsWeb) {
      try {
        await server.start();
        state = state.copyWith(status: 'Server running');
      } catch (e) {
        state = state.copyWith(status: 'Server failed: $e');
      }
    } else {
      state = state.copyWith(status: 'Server disabled on mobile/web');
    }
  }

  void updateStatus(String status) {
    state = state.copyWith(status: status);
  }

  void addActivity(String activity) {
    state = state.copyWith(activities: [...state.activities, activity]);
  }
}

// Providers
final rpcServerStateProvider =
    StateNotifierProvider<ServerStateNotifier, ServerState>((ref) {
      final server = ActivityRpcServer({});
      final notifier = ServerStateNotifier(server);
      server.updateHandlers({
        'connection': (socket) {
          final clientId =
              socket is _WsSocketWrapper
                  ? socket.clientId
                  : (socket as IpcSocketWrapper).clientId;
          notifier.updateStatus('Client connected (ID: $clientId)');
          socket.send({
            'cmd': 'DISPATCH',
            'data': {
              'v': 1,
              'config': {
                'cdn_host': 'fake.cdn',
                'api_endpoint': '//fake.api',
                'environment': 'dev',
              },
              'user': {
                'id': 'fake_user_id',
                'username': 'FakeUser',
                'discriminator': '0001',
                'avatar': null,
                'bot': false,
              },
            },
            'evt': 'READY',
            'nonce': '12345',
          });
        },
        'message': (socket, dynamic data) async {
          if (data['cmd'] == 'SET_ACTIVITY') {
            notifier.addActivity(
              'Activity: ${data['args']['activity']['details'] ?? 'Unknown'}',
            );
            final label = data['args']['activity']['details'] ?? 'Unknown';
            final appId = socket.clientId;
            try {
              await setRemoteActivityStatus(ref, label, appId);
            } catch (e) {
              developer.log(
                'Failed to set remote activity status: $e',
                name: kRpcLogPrefix,
              );
            }
            socket.send({
              'cmd': 'SET_ACTIVITY',
              'data': data['args']['activity'],
              'evt': null,
              'nonce': data['nonce'],
            });
          }
        },
        'close': (socket) async {
          notifier.updateStatus('Client disconnected');
          final appId = socket.clientId;
          try {
            await unsetRemoteActivityStatus(ref, appId);
          } catch (e) {
            developer.log(
              'Failed to unset remote activity status: $e',
              name: kRpcLogPrefix,
            );
          }
        },
      });
      return notifier;
    });

final rpcServerProvider = Provider<ActivityRpcServer>((ref) {
  final notifier = ref.watch(rpcServerStateProvider.notifier);
  return notifier.server;
});

Future<void> setRemoteActivityStatus(
  Ref ref,
  String label,
  String appId,
) async {
  final apiClient = ref.read(apiClientProvider);
  await apiClient.post(
    '/id/accounts/me/statuses',
    data: {
      'is_invisible': false,
      'is_not_disturb': false,
      'is_automated': true,
      'label': label,
      'app_identifier': appId,
    },
  );
}

Future<void> unsetRemoteActivityStatus(Ref ref, String appId) async {
  final apiClient = ref.read(apiClientProvider);
  await apiClient.delete(
    '/id/accounts/me/statuses',
    queryParameters: {'app': appId},
  );
}