Create self verification start screen.

Riot/Modules/KeyVerification/Device/SelfVerifyStart/KeyVerificationSelfVerifyStartViewModel.swift

@@ -0,0 +1,144 @@
+// File created from ScreenTemplate
+// $ createScreen.sh KeyVerification KeyVerificationSelfVerifyStart
+/*
+ Copyright 2020 New Vector Ltd
+ 
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+ 
+ http://www.apache.org/licenses/LICENSE-2.0
+ 
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ */
+
+import Foundation
+
+final class KeyVerificationSelfVerifyStartViewModel: KeyVerificationSelfVerifyStartViewModelType {
+    
+    // MARK: - Properties
+    
+    // MARK: Private
+
+    private let session: MXSession
+    private let otherDeviceId: String
+    private let verificationManager: MXKeyVerificationManager
+    private let keyVerificationService: KeyVerificationService
+    
+    private var keyVerificationRequest: MXKeyVerificationRequest?
+    
+    // MARK: Public    
+
+    weak var viewDelegate: KeyVerificationSelfVerifyStartViewModelViewDelegate?
+    weak var coordinatorDelegate: KeyVerificationSelfVerifyStartViewModelCoordinatorDelegate?
+    
+    // MARK: - Setup
+    
+    init(session: MXSession, otherDeviceId: String) {
+        self.session = session
+        self.verificationManager = session.crypto.keyVerificationManager
+        self.otherDeviceId = otherDeviceId
+        self.keyVerificationService = KeyVerificationService()
+    }
+    
+    deinit {
+    }
+    
+    // MARK: - Public
+    
+    func process(viewAction: KeyVerificationSelfVerifyStartViewAction) {
+        switch viewAction {
+        case .loadData:
+            self.loadData()
+        case .startVerification:
+            self.startVerification()
+        case .cancel:
+            self.cancelKeyVerificationRequest()
+            self.coordinatorDelegate?.keyVerificationSelfVerifyStartViewModelDidCancel(self)
+        }
+    }
+    
+    // MARK: - Private
+    
+    private func loadData() {
+        self.startVerification()
+    }
+    
+    private func startVerification() {
+        self.update(viewState: .verificationPending)
+        
+        self.verificationManager.requestVerificationByToDevice(withUserId: session.myUser.userId, deviceIds: [otherDeviceId], methods: self.keyVerificationService.supportedKeyVerificationMethods(), success: { [weak self] (keyVerificationRequest) in
+            guard let self = self else {
+                return
+            }
+            
+            self.keyVerificationRequest = keyVerificationRequest
+            self.update(viewState: .loaded)
+            self.registerKeyVerificationRequestDidChangeNotification(for: keyVerificationRequest)
+            }, failure: { [weak self]  error in
+                self?.update(viewState: .error(error))
+        })
+    }
+    
+    private func update(viewState: KeyVerificationSelfVerifyStartViewState) {
+        self.viewDelegate?.keyVerificationSelfVerifyStartViewModel(self, didUpdateViewState: viewState)
+    }        
+    
+    private func cancelKeyVerificationRequest() {
+        guard let keyVerificationRequest = self.keyVerificationRequest  else {
+            return
+        }
+        
+        keyVerificationRequest.cancel(with: MXTransactionCancelCode.user(), success: nil, failure: nil)
+    }
+    
+    // MARK: - MXKeyVerificationRequestDidChange
+    
+    private func registerKeyVerificationRequestDidChangeNotification(for keyVerificationRequest: MXKeyVerificationRequest) {
+        NotificationCenter.default.addObserver(self, selector: #selector(keyVerificationRequestDidChange(notification:)), name: .MXKeyVerificationRequestDidChange, object: keyVerificationRequest)
+    }
+    
+    private func unregisterKeyVerificationRequestDidChangeNotification() {
+        NotificationCenter.default.removeObserver(self, name: .MXKeyVerificationRequestDidChange, object: nil)
+    }
+    
+    @objc private func keyVerificationRequestDidChange(notification: Notification) {
+        guard let keyVerificationRequest = notification.object as? MXKeyVerificationRequest else {
+            return
+        }
+        
+        guard let currentKeyVerificationRequest = self.keyVerificationRequest, keyVerificationRequest.requestId == currentKeyVerificationRequest.requestId else {
+            return
+        }
+        
+        switch keyVerificationRequest.state {
+        case MXKeyVerificationRequestStateAccepted:
+            self.unregisterKeyVerificationRequestDidChangeNotification()
+            self.coordinatorDelegate?.keyVerificationSelfVerifyStartViewModel(self, otherDidAcceptRequest: currentKeyVerificationRequest)
+        case MXKeyVerificationRequestStateReady:
+            self.unregisterKeyVerificationRequestDidChangeNotification()
+            self.coordinatorDelegate?.keyVerificationSelfVerifyStartViewModel(self, otherDidAcceptRequest: currentKeyVerificationRequest)
+        case MXKeyVerificationRequestStateCancelled:
+            guard let reason = keyVerificationRequest.reasonCancelCode else {
+                return
+            }
+            self.unregisterKeyVerificationRequestDidChangeNotification()
+            self.update(viewState: .cancelled(reason))
+        case MXKeyVerificationRequestStateCancelledByMe:
+            guard let reason = keyVerificationRequest.reasonCancelCode else {
+                return
+            }
+            self.unregisterKeyVerificationRequestDidChangeNotification()
+            self.update(viewState: .cancelledByMe(reason))
+        case MXKeyVerificationRequestStateExpired:
+            self.unregisterKeyVerificationRequestDidChangeNotification()
+            self.update(viewState: .error(UserVerificationStartViewModelError.keyVerificationRequestExpired))
+        default:
+            break
+        }
+    }
+}