[Messenger example] create new group

xx-messenger example

• Add groups list screen
• Add new group screen
• Implement creating new group

Examples/xx-messenger/Sources/NewGroupFeature/NewGroupComponent.swift

 import AppCore
 import ComposableArchitecture
 import Foundation
+import XXMessengerClient
 import XXModels
 
 public struct NewGroupComponent: ReducerProtocol {
   public struct State: Equatable {
     public init(
-      contacts: IdentifiedArrayOf<XXModels.Contact> = []
+      contacts: IdentifiedArrayOf<XXModels.Contact> = [],
+      members: IdentifiedArrayOf<XXModels.Contact> = []
     ) {
       self.contacts = contacts
+      self.members = members
     }
 
     public var contacts: IdentifiedArrayOf<XXModels.Contact>
+    public var members: IdentifiedArrayOf<XXModels.Contact>
   }
 
   public enum Action: Equatable {
     case start
     case didFetchContacts([XXModels.Contact])
+    case didSelectContact(XXModels.Contact)
     case didFinish
   }
 
   public init() {}
 
+  @Dependency(\.app.messenger) var messenger: Messenger
   @Dependency(\.app.dbManager.getDB) var db: DBManagerGetDB
   @Dependency(\.app.mainQueue) var mainQueue: AnySchedulerOf<DispatchQueue>
   @Dependency(\.app.bgQueue) var bgQueue: AnySchedulerOf<DispatchQueue>
@@ -29,10 +35,12 @@ public struct NewGroupComponent: ReducerProtocol {
   public func reduce(into state: inout State, action: Action) -> EffectTask<Action> {
     switch action {
     case .start:
+      let myId = try? messenger.e2e.tryGet().getContact().getId()
       return Effect
         .catching { try db() }
         .flatMap { $0.fetchContactsPublisher(.init()) }
         .assertNoFailure()
+        .map { $0.filter { $0.id != myId } }
         .map(Action.didFetchContacts)
         .subscribe(on: bgQueue)
         .receive(on: mainQueue)
@@ -42,6 +50,14 @@ public struct NewGroupComponent: ReducerProtocol {
       state.contacts = IdentifiedArray(uniqueElements: contacts)
       return .none
 
+    case .didSelectContact(let contact):
+      if state.members.contains(contact) {
+        state.members.remove(contact)
+      } else {
+        state.members.append(contact)
+      }
+      return .none
+
     case .didFinish:
       return .none
     }