Membership aware room routes (#2709)

* Remove the invites button when room list invites are enabled

* element-hq/element-x-ios/issues/2632 - Handle room permalinks based on their membership state and show the according room joining screens:
- modify the room flow coordinator to only take a roomID and be able to decide its own room flows (especially for unjoined rooms)
- add support for the new room preview API
- have RoomDirectorySearch go through the same paths

ElementX/Sources/Screens/JoinRoomScreen/JoinRoomScreenViewModel.swift

@@ -20,20 +20,28 @@ import SwiftUI
 typealias JoinRoomScreenViewModelType = StateStoreViewModel<JoinRoomScreenViewState, JoinRoomScreenViewAction>
 
 class JoinRoomScreenViewModel: JoinRoomScreenViewModelType, JoinRoomScreenViewModelProtocol {
+    private let roomID: String
     private let clientProxy: ClientProxyProtocol
+    private let userIndicatorController: UserIndicatorControllerProtocol
     
     private let actionsSubject: PassthroughSubject<JoinRoomScreenViewModelAction, Never> = .init()
     var actionsPublisher: AnyPublisher<JoinRoomScreenViewModelAction, Never> {
         actionsSubject.eraseToAnyPublisher()
     }
 
-    init(roomID: String, roomName: String, avatarURL: URL?, interaction: JoinRoomScreenInteraction, clientProxy: ClientProxyProtocol) {
+    init(roomID: String,
+         clientProxy: ClientProxyProtocol,
+         mediaProvider: MediaProviderProtocol,
+         userIndicatorController: UserIndicatorControllerProtocol) {
+        self.roomID = roomID
         self.clientProxy = clientProxy
+        self.userIndicatorController = userIndicatorController
         
-        super.init(initialViewState: JoinRoomScreenViewState(roomID: roomID,
-                                                             roomName: roomName,
-                                                             avatarURL: avatarURL,
-                                                             interaction: interaction))
+        super.init(initialViewState: JoinRoomScreenViewState(roomID: roomID), imageProvider: mediaProvider)
+        
+        Task {
+            await loadRoomDetails()
+        }
     }
     
     // MARK: - Public
@@ -47,21 +55,93 @@ class JoinRoomScreenViewModel: JoinRoomScreenViewModelType, JoinRoomScreenViewMo
         case .join:
             Task { await joinRoom() }
         case .acceptInvite:
-            break
+            Task { await joinRoom() }
         case .declineInvite:
-            break
+            showDeclineInviteConfirmationAlert()
         }
     }
     
+    func stop() {
+        hideLoadingIndicator()
+    }
+    
     // MARK: - Private
     
-    private func joinRoom() async {
-        state.isJoining = true
-        switch await clientProxy.joinRoom(state.roomID) {
-        case .success:
-            actionsSubject.send(.joined)
+    private func loadRoomDetails() async {
+        showLoadingIndicator()
+        
+        defer {
+            hideLoadingIndicator()
+        }
+        
+        switch await clientProxy.roomPreviewForIdentifier(roomID) {
+        case .success(let roomDetails):
+            state.roomDetails = roomDetails
         case .failure:
-            state.bindings.alertInfo = .init(id: .joinFailed)
+            userIndicatorController.submitIndicator(UserIndicator(title: L10n.errorUnknown))
         }
     }
+    
+    private func joinRoom() async {
+        showLoadingIndicator()
+        
+        defer {
+            hideLoadingIndicator()
+        }
+        
+        switch await clientProxy.joinRoom(roomID) {
+        case .success:
+            actionsSubject.send(.joined)
+        case .failure(let error):
+            MXLog.error("Failed joining room with error: \(error)")
+            userIndicatorController.submitIndicator(.init(title: L10n.errorUnknown))
+        }
+    }
+    
+    private func showDeclineInviteConfirmationAlert() {
+        guard let roomDetails = state.roomDetails else {
+            userIndicatorController.submitIndicator(.init(title: L10n.errorUnknown))
+            return
+        }
+        
+        let roomName = roomDetails.name ?? roomID
+        state.bindings.alertInfo = .init(id: .declineInvite,
+                                         title: L10n.screenInvitesDeclineChatTitle,
+                                         message: L10n.screenInvitesDeclineChatMessage(roomName),
+                                         primaryButton: .init(title: L10n.actionCancel, role: .cancel, action: nil),
+                                         secondaryButton: .init(title: L10n.actionDecline, role: .destructive, action: { Task { await self.declineInvite() } }))
+    }
+    
+    private func declineInvite() async {
+        defer {
+            userIndicatorController.retractIndicatorWithId(roomID)
+        }
+        
+        userIndicatorController.submitIndicator(UserIndicator(id: roomID, type: .modal, title: L10n.commonLoading, persistent: true))
+        
+        guard let roomProxy = await clientProxy.roomForIdentifier(roomID) else {
+            userIndicatorController.submitIndicator(.init(title: L10n.errorUnknown))
+            return
+        }
+        
+        let result = await roomProxy.rejectInvitation()
+        
+        if case .failure = result {
+            userIndicatorController.submitIndicator(.init(title: L10n.errorUnknown))
+        }
+    }
+    
+    private static let loadingIndicatorIdentifier = "\(JoinRoomScreenViewModel.self)-Loading"
+    
+    private func showLoadingIndicator() {
+        userIndicatorController.submitIndicator(UserIndicator(id: Self.loadingIndicatorIdentifier,
+                                                              type: .modal(progress: .indeterminate, interactiveDismissDisabled: false, allowsInteraction: true),
+                                                              title: L10n.commonLoading,
+                                                              persistent: true),
+                                                delay: .seconds(0.25))
+    }
+    
+    private func hideLoadingIndicator() {
+        userIndicatorController.retractIndicatorWithId(Self.loadingIndicatorIdentifier)
+    }
 }