Protecting against register account with same fingerprint

sdk/Sources/Sdk/APIError.swift

@@ -18,6 +18,7 @@ public extension Sdk {
         case noPrivateKey
         case noSignatureValues
         case urlError
+        case deviceExist
         
         case wrongToken
         case wrongSymbol

sdk/Sources/Sdk/Sdk.swift

@@ -292,6 +292,7 @@ public class Sdk {
             case 200:    return APIError.wrongToken
             case -1:        return APIError.wrongSymbol //Ya, Vulcan returns -1 code
             case 203:    return APIError.wrongPin
+            case 205:    return APIError.deviceExist
             default:    return nil
         }
     }

wulkanowy/Views/Login/LoginView.swift

@@ -5,8 +5,8 @@
 //  Created by Mikołaj on 25/10/2020.
 //
 
-
 import SwiftUI
+import KeychainAccess
 
 enum AvailableEndpoints: String, CaseIterable {
     case vulcan = "Vulcan"
@@ -22,7 +22,6 @@ open class Navigation: ObservableObject {
 }
 
 struct LoginView: View {
-    
     @StateObject var vulcan: VulcanStore = VulcanStore.shared
     
     @State private var token: String = ""
@@ -35,6 +34,7 @@ struct LoginView: View {
     @State private var loginStatus: String = ""
     @State private var willMoveToNextScreen = false
     @State private var success = false
+    @State private var showingAlert = false
     
     let cellHeight: CGFloat = 55
     let cornerRadius: CGFloat = 12
@@ -58,13 +58,30 @@ struct LoginView: View {
                         case "wrongPin":
                             buttonValue = String(format: NSLocalizedString("\(error)", comment: "loginButton"))
                             
+                        case "deviceExist":
+                            showingAlert.toggle()
+                        
                         default:
                             buttonValue = String(format: NSLocalizedString("invalidData", comment: "loginButton"))
                         }
                     } else {
                         print("success")
+                        let keychain = Keychain()
+                        let keyFingerprint = keychain["keyFingerprint"]
+                        let allStudentsKeys = keychain["allStudentsKeys"]
+                        
+                        let data = Data(allStudentsKeys!.utf8)
+                        do {
+                            let array = try JSONSerialization.jsonObject(with: data) as! [String]
+                            if array.contains(keyFingerprint!) {
+                                showingAlert.toggle()
+                            } else {
                                 success = true
                             }
+                        } catch {
+                            print(error)
+                        }
+                    }
             }
         }
     }
@@ -191,9 +208,12 @@ struct LoginView: View {
                     .frame(maxWidth: .infinity)
                     .background(Color.accentColor.opacity(0.1))
                     .cornerRadius(cornerRadius)
-            }
+                
-            .padding()
+            }.padding()
+            .alert(isPresented: $showingAlert) {
+                Alert(title: Text("Konto zarejestrowane"), message: Text("Konto zostało już zarejestrowane. Proszę zalogowaź się na inne konto."), dismissButton: .default(Text("OK")))}
                 Spacer()
+            
         }
     }
 }

wulkanowy/Views/Login/accountManager.swift

@@ -21,6 +21,7 @@ struct AccountManagerView: View {
         
         //parsing allStudentsKeys to array
         var allStudents: [String] = []
+        if(allStudentsKeys != "[]"){
             let data = Data(allStudentsKeys.utf8)
             do {
                 let keys = try JSONSerialization.jsonObject(with: data) as! [String]
@@ -33,6 +34,7 @@ struct AccountManagerView: View {
             } catch {
                 print(error)
             }
+        }
         
         return allStudents
     }

wulkanowy/Views/Login/chooseStudent.swift

@@ -73,6 +73,7 @@ struct ChooseStudentView: View {
                 allStudents.append(keyFingerprint!)
                 keychain["allStudentsKeys"] = "\(allStudents)"
                 
+                
                 //saving student
                 keychain["student-\(String(describing: keyFingerprint!))"] = "\(json["Envelope"][i])"