[Wallet] Fix firebase initialization error on iOS after reinstalling …

…the app (#1423)

packages/mobile/ios/celo/AppDelegate.m

@@ -23,10 +23,18 @@
 #import "RNFirebaseNotifications.h"
 #import "RNFirebaseMessaging.h"
 
+// Use same key as react-native-secure-key-store
+// so we don't reset already working installs
+static NSString * const kHasRunBeforeKey = @"RnSksIsAppInstalled";
+
 @implementation AppDelegate
 
 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
 {
+  // Reset keychain on first run to clear existing Firebase credentials
+  // Note: react-native-secure-key-store also does that but is run too late
+  // and hence can't clear Firebase credentials
+  [self resetKeychainIfNecessary];
   [FIRApp configure];
   [RNFirebaseNotifications configure];
   RCTBridge *bridge = [[RCTBridge alloc] initWithDelegate:self launchOptions:launchOptions];
@@ -68,4 +76,27 @@ - (void)application:(UIApplication *)application didRegisterUserNotificationSett
   [[RNFirebaseMessaging instance] didRegisterUserNotificationSettings:notificationSettings];
 }
 
+// Reset keychain on first app run, this is so we don't run with leftover items
+// after reinstalling the app
+- (void)resetKeychainIfNecessary
+{
+  NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
+  if ([defaults boolForKey:kHasRunBeforeKey]) {
+    return;
+  }
+
+  NSArray *secItemClasses = @[(__bridge id)kSecClassGenericPassword,
+                              (__bridge id)kSecAttrGeneric,
+                              (__bridge id)kSecAttrAccount,
+                              (__bridge id)kSecClassKey,
+                              (__bridge id)kSecAttrService];
+  for (id secItemClass in secItemClasses) {
+    NSDictionary *spec = @{(__bridge id)kSecClass:secItemClass};
+    SecItemDelete((__bridge CFDictionaryRef)spec);
+  }
+
+  [defaults setBool:YES forKey:kHasRunBeforeKey];
+  [defaults synchronize];
+}
+
 @end

packages/mobile/src/firebase/firebase.ts

@@ -21,6 +21,10 @@ export const initializeAuth = async (app: Firebase, address: string) => {
   await userRef.child(user.user.uid).transaction((userData) => {
     if (userData == null) {
       return { address }
+    } else if (userData.address !== undefined && userData.address !== address) {
+      // This shouldn't happen! If this is thrown it means the firebase user is reused
+      // with different addresses (which we don't want) or the db was incorrectly changed remotely!
+      throw new Error("User address in the db doesn't match persisted address")
     }
   })
   Logger.info(TAG, 'Firebase Auth initialized successfully')