Create set pin module & enter pin screen

Riot/Modules/SetPinCode/EnterPinCode/EnterPinCodeViewModel.swift

@@ -0,0 +1,112 @@
+// File created from ScreenTemplate
+// $ createScreen.sh SetPinCode/EnterPinCode EnterPinCode
+/*
+ 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 EnterPinCodeViewModel: EnterPinCodeViewModelType {
+    
+    // MARK: - Properties
+    
+    // MARK: Private
+
+    private let session: MXSession?
+    
+    private var currentOperation: MXHTTPOperation?
+    private var firstPin: String = ""
+    private var currentPin: String = "" {
+        didSet {
+            self.viewDelegate?.enterPinCodeViewModel(self, didUpdatePlaceholdersCount: currentPin.count)
+        }
+    }
+    
+    // MARK: Public
+
+    weak var viewDelegate: EnterPinCodeViewModelViewDelegate?
+    weak var coordinatorDelegate: EnterPinCodeViewModelCoordinatorDelegate?
+    
+    // MARK: - Setup
+    
+    init(session: MXSession?) {
+        self.session = session
+    }
+    
+    deinit {
+        self.cancelOperations()
+    }
+    
+    // MARK: - Public
+    
+    func process(viewAction: EnterPinCodeViewAction) {
+        switch viewAction {
+        case .digitPressed(let tag):
+            self.digitPressed(tag)
+        case .cancel:
+            self.cancelOperations()
+            self.coordinatorDelegate?.enterPinCodeViewModelDidCancel(self)
+        }
+    }
+    
+    // MARK: - Private
+    
+    private func digitPressed(_ tag: Int) {
+        if tag == -1 {
+            //  delete tapped
+            if currentPin.isEmpty {
+                return
+            } else {
+                currentPin.removeLast()
+            }
+        } else {
+            //  a digit tapped
+            currentPin += "\(tag)"
+            
+            if currentPin.count == 4 {
+                if firstPin.isEmpty {
+                    //  go to next screen
+                    firstPin = currentPin
+                    currentPin = ""
+                    self.update(viewState: .confirmPin)
+                } else {
+                    //  check first and second pins
+                    if firstPin == currentPin {
+                        self.coordinatorDelegate?.enterPinCodeViewModel(self, didCompleteWithPin: firstPin)
+                    } else {
+                        self.update(viewState: .pinsDontMatch(NSError(domain: "", code: -1002, userInfo: nil)))
+                        firstPin = ""
+                        currentPin = ""
+                        self.update(viewState: .enterFirstPin)
+                    }
+                }
+                
+                return
+            }
+        }
+    }
+    
+    private func loadData() {
+        self.update(viewState: .enterFirstPin)
+    }
+    
+    private func update(viewState: EnterPinCodeViewState) {
+        self.viewDelegate?.enterPinCodeViewModel(self, didUpdateViewState: viewState)
+    }
+    
+    private func cancelOperations() {
+        self.currentOperation?.cancel()
+    }
+}