import "dart:ffi";
import "dart:io";
import "dart:isolate";
import "dart:math";
import "package:fast_immutable_collections/fast_immutable_collections.dart";
import "package:ffi/ffi.dart";
import "package:flutter/foundation.dart";
import "package:nexus/controllers/account_data.dart";
import "package:nexus/controllers/client_state.dart";
import "package:nexus/controllers/init_complete.dart";
import "package:nexus/controllers/rooms.dart";
import "package:nexus/controllers/space_edges.dart";
import "package:nexus/controllers/sync_status.dart";
import "package:nexus/controllers/top_level_spaces.dart";
import "package:nexus/helpers/extensions/gomuks_buffer.dart";
import "package:nexus/main.dart";
import "package:nexus/models/content/message.dart";
import "package:nexus/models/event.dart";
import "package:nexus/models/oauth_auth_code_response.dart";
import "package:nexus/models/open_graph_data.dart";
import "package:nexus/models/paginate.dart";
import "package:nexus/models/requests/download_media.dart";
import "package:nexus/models/requests/get_event.dart";
import "package:nexus/models/requests/get_related_events.dart";
import "package:nexus/models/requests/get_room_state.dart";
import "package:nexus/models/requests/join_room.dart";
import "package:nexus/models/profile_response.dart";
import "package:nexus/models/requests/oauth/exchange_token.dart";
import "package:nexus/models/requests/oauth/get_auth_url.dart";
import "package:nexus/models/requests/oauth/register_client.dart";
import "package:nexus/models/requests/paginate.dart";
import "package:nexus/models/requests/redact_event.dart";
import "package:nexus/models/requests/report.dart";
import "package:nexus/models/requests/send_event.dart";
import "package:nexus/models/requests/send_message.dart";
import "package:nexus/models/requests/set_account_data.dart";
import "package:nexus/models/requests/set_membership.dart";
import "package:nexus/models/requests/set_state.dart";
import "package:nexus/models/requests/upload_media.dart";
import "package:nexus/models/room.dart";
import "package:nexus/models/spec_versions_response.dart";
import "package:nexus/models/sync_data.dart";
import "package:nexus/src/third_party/gomuks.g.dart";
import "package:flutter_riverpod/flutter_riverpod.dart";
import "package:path_provider/path_provider.dart";

class ClientController extends AsyncNotifier<int> {
  @override
  Future<int> build() async {
    final Pointer<Char> root;
    if (Platform.isAndroid || Platform.isIOS) {
      final dir = await getApplicationSupportDirectory();
      root = "${dir.path}/gomuks".toNativeUtf8().cast();
    } else {
      root = nullptr.cast();
    }

    final handle = GomuksInit(root);

    final callable =
        NativeCallable<
          Void Function(Pointer<Char>, Int64, GomuksOwnedBuffer)
        >.listener((
          Pointer<Char> command,
          int requestId,
          GomuksOwnedBuffer data,
        ) {
          try {
            final muksEventType = command.cast<Utf8>().toDartString();
            debugPrint("Handling $muksEventType...");
            final decodedMuksEvent = data.toJson();

            switch (muksEventType) {
              case "client_state":
                ref
                    .watch(ClientStateController.provider.notifier)
                    .set(.fromJson(decodedMuksEvent));
                break;
              case "sync_status":
                ref
                    .watch(SyncStatusController.provider.notifier)
                    .set(.fromJson(decodedMuksEvent));
                break;
              case "init_complete":
                ref.watch(InitCompleteController.provider.notifier).complete();
                break;
              case "send_complete":
                final event = Event.fromJson(decodedMuksEvent["event"]);
                ref
                    .watch(RoomsController.provider.notifier)
                    .update(
                      .new({
                        event.roomId: .new(events: .new({event.rowId: event})),
                      }),
                      .new(),
                    );

                break;
              case "sync_complete":
                final syncData = SyncData.fromJson(decodedMuksEvent);
                final roomProvider = RoomsController.provider;
                final accountDataProvider = AccountDataController.provider;

                if (syncData.clearState) {
                  ref.invalidate(roomProvider);
                  ref.invalidate(accountDataProvider);
                }

                ref
                    .watch(roomProvider.notifier)
                    .update(syncData.rooms, syncData.leftRooms);
                ref
                    .watch(accountDataProvider.notifier)
                    .update(syncData.accountData);

                if (syncData.topLevelSpaces != null) {
                  ref
                      .watch(TopLevelSpacesController.provider.notifier)
                      .set(syncData.topLevelSpaces!);
                }

                if (syncData.spaceEdges != null) {
                  ref
                      .watch(SpaceEdgesController.provider.notifier)
                      .set(syncData.spaceEdges!);
                }

                // ref
                //     .watch(SyncStatusController.provider.notifier)
                //     .set(SyncStatus.fromJson(decodedMuksEvent));
                break;
              default:
                debugPrint("Unhandled event: $muksEventType");
            }
            debugPrint("Finished handling $muksEventType...");
          } catch (error, stackTrace) {
            if (kDebugMode) {
              debugPrintStack(stackTrace: stackTrace, label: error.toString());
              rethrow;
            } else {
              showError(error, stackTrace);
            }
          }
        });

    ref.onDispose(() => GomuksDestroy(handle));
    ref.onDispose(callable.close);

    final errorCode = GomuksStart(handle, callable.nativeFunction);

    if (errorCode == 0) return handle;
    throw Exception("GomuksStart returned error code $errorCode");
  }

  Future<dynamic> _sendCommand(
    String command, [
    Map<String, dynamic> data = const {},
  ]) async {
    final bufferPointer = data.toGomuksBufferPtr();
    final handle = await future;
    final response = await Isolate.run(
      () => GomuksSubmitCommand(
        handle,
        command.toNativeUtf8().cast<Char>(),
        bufferPointer.ref,
      ),
    );

    calloc.free(bufferPointer);

    final json = response.buf.toJson();
    if (response.command.cast<Utf8>().toDartString() == "error") {
      throw json;
    }

    return json;
  }

  Future<void> redactEvent(RedactEventRequest report) =>
      _sendCommand("redact_event", report.toJson());

  Future<Event> sendMessage(SendMessageRequest request) async =>
      Event.fromJson(await _sendCommand("send_message", request.toJson()));

  Future<Event> sendEvent(SendEventRequest request) async {
    final json = request.toJson();
    final content = request.content.toJson();

    return Event.fromJson(
      await _sendCommand("send_event", {
        ...json,
        "content": {
          ...content,
          "m.relates_to": {
            ...((content["m.relates_to"] as Map<String, dynamic>?) ?? {}),
            "event_id": request.relatesTo,
            "rel_type": request.relationType,
          },
        },
      }),
    );
  }

  Future<String?> setState(SetStateRequest request) async =>
      await _sendCommand("set_state", request.toJson());

  Future<String?> verify(String recoveryKey) async {
    try {
      await _sendCommand("verify", {"recovery_key": recoveryKey});
      return null;
    } catch (error) {
      return error.toString();
    }
  }

  Future<String> joinRoom(JoinRoomRequest request) async {
    final response = await _sendCommand("join_room", request.toJson());
    return response["room_id"];
  }

  Future<void> leaveRoom(Room room) async {
    if (room.metadata == null) return;
    await _sendCommand("leave_room", {"room_id": room.metadata!.id});
  }

  // (await _sendCommand("get_event_context", {
  //   "room_id": request.roomId,
  //   "event_id": r"$OqZT4NuTj0J1-771IOEEWRI4XdumRNu6ighlvO3K3gc",
  // }));

  Future<IList<Event>> getRoomState(GetRoomStateRequest request) async {
    Future<List?> getState(GetRoomStateRequest request) async =>
        (await _sendCommand("get_room_state", request.toJson())) as List?;
    final response = await getState(request);

    return .new(
      (response ?? await getState(request.copyWith(refetch: true)) ?? []).map(
        (event) => .fromJson(event),
      ),
    );
  }

  Future<IList<Event>?> getRelatedEvents(
    GetRelatedEventsRequest request,
  ) async {
    final response =
        (await _sendCommand("get_related_events", request.toJson())) as List?;
    return .new(response?.map((event) => .fromJson(event)));
  }

  Future<Event?> getEvent(GetEventRequest request) async {
    final json = await _sendCommand("get_event", request.toJson());
    return json == null ? null : .fromJson(json);
  }

  Future<OpenGraphData> getUrlPreview(Uri url) async =>
      .fromJson(await _sendCommand("get_url_preview", {"url": url.toString()}));

  Future<Paginate> paginate(PaginateRequest request) async =>
      .fromJson(await _sendCommand("paginate", request.toJson()));

  Future<ProfileResponse> getProfile(String userId) async =>
      .fromJson(await _sendCommand("get_profile", {"user_id": userId}));

  Future<void> reportEvent(ReportRequest request) =>
      _sendCommand("report_event", request.toJson());

  Future<void> setMembership(SetMembershipRequest request) =>
      _sendCommand("set_membership", request.toJson());

  Future<void> setAccountData(SetAccountDataRequest request) =>
      _sendCommand("set_account_data", request.toJson());

  Future<MessageContent> uploadMedia(UploadMediaRequest request) async =>
      .fromJson(await _sendCommand("upload_media", request.toJson()));

  Future<File> downloadMedia(DownloadMediaRequest request) async =>
      .new((await _sendCommand("download_media", request.toJson()))["path"]);

  Future<void> logout() => _sendCommand("logout");

  Future<void> markRead(Room room) async {
    final eventRowId = room.timeline[room.timeline.keys.reduce(max)];
    final event = eventRowId == null ? null : room.events[eventRowId];
    if (event == null || room.metadata == null) return;

    await _sendCommand("mark_read", {
      "room_id": room.metadata!.id,
      "receipt_type": "m.read",
      "event_id": event.eventId,
    });
  }

  Future<String> registerClient(OAuthRegisterClientRequest request) async =>
      (await _sendCommand(
        "oauth_register_client",
        request.toJson(),
      ))["client_id"];

  Future<OAuthAuthCodeResponse> getAuthUrl(OAuthGetAuthUrl request) async =>
      .fromJson(
        await _sendCommand("oauth_get_authorization_url", request.toJson()),
      );

  Future<void> exchangeToken(OAuthExchangeTokenRequest request) async =>
      await _sendCommand("oauth_exchange_token", request.toJson());

  Future<SpecVersionsResponse> getSpecVersions() async =>
      .fromJson(await _sendCommand("get_versions"));

  Future<Uri?> discoverHomeserver(Uri homeserver) async {
    try {
      final response = await _sendCommand("discover_homeserver", {
        "user_id": "@fake-user:${homeserver.host}",
      });
      return Uri.parse(response["m.homeserver"]?["base_url"]);
    } catch (error) {
      return null;
    }
  }

  static final provider = AsyncNotifierProvider<ClientController, int>(
    ClientController.new,
  );
}