refactor(job): Implement polymorphic predicate for job accessibility

Now every job type can impement canAddTo function to make JobsCubit know whether it can be applied or not

lib/logic/cubit/client_jobs/client_jobs_cubit.dart

@@ -24,10 +24,13 @@ class JobsCubit extends Cubit<JobsState> {
   final ServicesCubit servicesCubit;
 
   void addJob(final ClientJob job) {
-    _updateJobsState([
+    final jobs = currentJobList;
-      ...currentJobList,
+    if (job.canAddTo(jobs)) {
-      ...[job]
+      _updateJobsState([
-    ]);
+        ...jobs,
+        ...[job],
+      ]);
+    }
   }
 
   void removeJob(final String id) {
@@ -35,25 +38,6 @@ class JobsCubit extends Cubit<JobsState> {
     emit(newState);
   }
 
-  void createOrRemoveServiceToggleJob(final ToggleJob job) {
-    final List<ClientJob> newJobsList = <ClientJob>[];
-    if (state is JobsStateWithJobs) {
-      newJobsList.addAll((state as JobsStateWithJobs).clientJobList);
-    }
-    final bool needToRemoveJob = newJobsList
-        .any((final el) => el is ServiceToggleJob && el.id == job.id);
-    if (needToRemoveJob) {
-      final ClientJob removingJob = newJobsList.firstWhere(
-        (final el) => el is ServiceToggleJob && el.id == job.id,
-      );
-      removeJob(removingJob.id);
-    } else {
-      newJobsList.add(job);
-      getIt<NavigationService>().showSnackBar('jobs.job_added'.tr());
-      emit(JobsStateWithJobs(newJobsList));
-    }
-  }
-
   List<ClientJob> get currentJobList {
     final List<ClientJob> jobs = <ClientJob>[];
     if (state is JobsStateWithJobs) {
@@ -68,17 +52,6 @@ class JobsCubit extends Cubit<JobsState> {
     emit(JobsStateWithJobs(newJobs));
   }
 
-  void addUniqueJob<J extends ClientJob>(final J job) {
-    final List<ClientJob> jobs = currentJobList;
-    final bool exists = jobs.any((final el) => el is J);
-    if (!exists) {
-      _updateJobsState([
-        ...jobs,
-        ...[job]
-      ]);
-    }
-  }
-
   Future<void> rebootServer() async {
     emit(JobsStateLoading());
     final bool isSuccessful = await api.reboot();

lib/logic/models/job.dart

@@ -17,6 +17,7 @@ abstract class ClientJob extends Equatable {
   final String title;
   final String id;
 
+  bool canAddTo(final List<ClientJob> jobs) => true;
   void execute(final JobsCubit cubit);
 
   @override
@@ -25,10 +26,14 @@ abstract class ClientJob extends Equatable {
 
 class RebuildServerJob extends ClientJob {
   RebuildServerJob({
-    required final super.title,
+    required super.title,
-    final super.id,
+    super.id,
   });
 
+  @override
+  bool canAddTo(final List<ClientJob> jobs) =>
+      super.canAddTo(jobs) && !jobs.any((final job) => job is RebuildServerJob);
+
   @override
   void execute(final JobsCubit cubit) async {
     await cubit.upgradeServer();
@@ -74,6 +79,12 @@ class DeleteUserJob extends ClientJob {
 
   final User user;
 
+  @override
+  bool canAddTo(final List<ClientJob> jobs) =>
+      super.canAddTo(jobs) &&
+      !jobs.any(
+          (final job) => job is DeleteUserJob && job.user.login == user.login);
+
   @override
   void execute(final JobsCubit cubit) async {
     await cubit.usersCubit.deleteUser(user);
@@ -83,33 +94,31 @@ class DeleteUserJob extends ClientJob {
   List<Object> get props => [id, title, user];
 }
 
-abstract class ToggleJob extends ClientJob {
+class ServiceToggleJob extends ClientJob {
-  ToggleJob({
-    required final this.service,
-    required final super.title,
-  });
-
-  final Service service;
-
-  @override
-  List<Object> get props => [...super.props, service];
-}
-
-class ServiceToggleJob extends ToggleJob {
   ServiceToggleJob({
-    required super.service,
+    required this.service,
     required this.needToTurnOn,
   }) : super(
           title:
               '${needToTurnOn ? "jobs.service_turn_on".tr() : "jobs.service_turn_off".tr()} ${service.displayName}',
         );
 
+  final bool needToTurnOn;
+  final Service service;
+
+  @override
+  bool canAddTo(final List<ClientJob> jobs) =>
+      super.canAddTo(jobs) &&
+      !jobs.any((final job) =>
+          job is ServiceToggleJob && job.service.id == service.id);
+
   @override
   void execute(final JobsCubit cubit) async {
     await cubit.api.switchService(service.id, needToTurnOn);
   }
 
-  final bool needToTurnOn;
+  @override
+  List<Object> get props => [...super.props, service];
 }
 
 class CreateSSHKeyJob extends ClientJob {
@@ -139,6 +148,14 @@ class DeleteSSHKeyJob extends ClientJob {
   final User user;
   final String publicKey;
 
+  @override
+  bool canAddTo(final List<ClientJob> jobs) =>
+      super.canAddTo(jobs) &&
+      !jobs.any((final job) =>
+          job is DeleteSSHKeyJob &&
+          job.publicKey == publicKey &&
+          job.user.login == user.login);
+
   @override
   void execute(final JobsCubit cubit) async {
     await cubit.usersCubit.deleteSshKey(user, publicKey);

lib/ui/pages/server_details/server_settings.dart

@@ -29,7 +29,7 @@ class _ServerSettingsState extends State<_ServerSettings> {
         SwitchListTile(
           value: allowAutoUpgrade ?? false,
           onChanged: (final switched) {
-            context.read<JobsCubit>().addUniqueJob(
+            context.read<JobsCubit>().addJob(
                   RebuildServerJob(title: 'jobs.upgrade_server'.tr()),
                 );
             context
@@ -54,7 +54,7 @@ class _ServerSettingsState extends State<_ServerSettings> {
         SwitchListTile(
           value: rebootAfterUpgrade ?? false,
           onChanged: (final switched) {
-            context.read<JobsCubit>().addUniqueJob(
+            context.read<JobsCubit>().addJob(
                   RebuildServerJob(title: 'jobs.upgrade_server'.tr()),
                 );
             context
@@ -82,7 +82,7 @@ class _ServerSettingsState extends State<_ServerSettings> {
             serverDetailsState.serverTimezone.toString(),
           ),
           onTap: () {
-            context.read<JobsCubit>().addUniqueJob(
+            context.read<JobsCubit>().addJob(
                   RebuildServerJob(title: 'jobs.upgrade_server'.tr()),
                 );
             Navigator.of(context).push(

lib/ui/pages/services/service_page.dart

@@ -89,7 +89,7 @@ class _ServicePageState extends State<ServicePage> {
         ListTile(
           iconColor: Theme.of(context).colorScheme.onBackground,
           onTap: () => {
-            context.read<JobsCubit>().createOrRemoveServiceToggleJob(
+            context.read<JobsCubit>().addJob(
                   ServiceToggleJob(
                     service: service,
                     needToTurnOn: serviceDisabled,

lib/ui/pages/services/services.dart

@@ -157,8 +157,7 @@ class _Card extends StatelessWidget {
 
                       return BrandSwitch(
                         value: isActive,
-                        onChanged: (final value) =>
+                        onChanged: (final value) => jobsCubit.addJob(
-                            jobsCubit.createOrRemoveServiceToggleJob(
                           ServiceToggleJob(
                             service: service,
                             needToTurnOn: value,