From f11d31db5ecf393c489f4b5d36cd7e7cb04a76df Mon Sep 17 00:00:00 2001
From: Alessio Moiso <a.moiso@outlook.com>
Date: Sun, 19 Apr 2020 22:40:07 +0200
Subject: [PATCH] Fix logout action, map all errors

---
 .../RxFireAuth/Base.lproj/LaunchScreen.xib    |  20 +-
 Example/RxFireAuth/Base.lproj/Main.storyboard |  36 +-
 Example/RxFireAuth/ViewController.swift       |   6 +-
 RxFireAuth/Classes/UserError.swift            |  79 ++++-
 RxFireAuth/Classes/UserManager.swift          | 320 +++++++++++-------
 RxFireAuth/Classes/UserManagerType.swift      |  12 +-
 6 files changed, 313 insertions(+), 160 deletions(-)

diff --git a/Example/RxFireAuth/Base.lproj/LaunchScreen.xib b/Example/RxFireAuth/Base.lproj/LaunchScreen.xib
index 0b2da49..ffd372a 100644
--- a/Example/RxFireAuth/Base.lproj/LaunchScreen.xib
+++ b/Example/RxFireAuth/Base.lproj/LaunchScreen.xib
@@ -1,12 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="13771" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" useTraitCollections="YES" colorMatched="YES">
-    <device id="retina4_7" orientation="portrait">
-        <adaptation id="fullscreen"/>
-    </device>
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="16096" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" useTraitCollections="YES" colorMatched="YES">
+    <device id="retina4_7" orientation="portrait" appearance="light"/>
     <dependencies>
         <deployment identifier="iOS"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="13772"/>
-        <capability name="Constraints with non-1.0 multipliers" minToolsVersion="5.1"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="16087"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
     <objects>
@@ -16,14 +13,8 @@
             <rect key="frame" x="0.0" y="0.0" width="480" height="480"/>
             <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
             <subviews>
-                <label opaque="NO" clipsSubviews="YES" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="  Copyright (c) 2015 CocoaPods. All rights reserved." textAlignment="center" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" minimumFontSize="9" translatesAutoresizingMaskIntoConstraints="NO" id="8ie-xW-0ye">
-                    <rect key="frame" x="20" y="439" width="441" height="21"/>
-                    <fontDescription key="fontDescription" type="system" pointSize="17"/>
-                    <color key="textColor" cocoaTouchSystemColor="darkTextColor"/>
-                    <nil key="highlightedColor"/>
-                </label>
                 <label opaque="NO" clipsSubviews="YES" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="RxFireAuth" textAlignment="center" lineBreakMode="middleTruncation" baselineAdjustment="alignBaselines" minimumFontSize="18" translatesAutoresizingMaskIntoConstraints="NO" id="kId-c2-rCX">
-                    <rect key="frame" x="20" y="140" width="441" height="43"/>
+                    <rect key="frame" x="20" y="139.5" width="440" height="43"/>
                     <fontDescription key="fontDescription" type="boldSystem" pointSize="36"/>
                     <color key="textColor" cocoaTouchSystemColor="darkTextColor"/>
                     <nil key="highlightedColor"/>
@@ -33,9 +24,6 @@
             <constraints>
                 <constraint firstItem="kId-c2-rCX" firstAttribute="centerY" secondItem="iN0-l3-epB" secondAttribute="bottom" multiplier="1/3" constant="1" id="5cJ-9S-tgC"/>
                 <constraint firstAttribute="centerX" secondItem="kId-c2-rCX" secondAttribute="centerX" id="Koa-jz-hwk"/>
-                <constraint firstAttribute="bottom" secondItem="8ie-xW-0ye" secondAttribute="bottom" constant="20" id="Kzo-t9-V3l"/>
-                <constraint firstItem="8ie-xW-0ye" firstAttribute="leading" secondItem="iN0-l3-epB" secondAttribute="leading" constant="20" symbolic="YES" id="MfP-vx-nX0"/>
-                <constraint firstAttribute="centerX" secondItem="8ie-xW-0ye" secondAttribute="centerX" id="ZEH-qu-HZ9"/>
                 <constraint firstItem="kId-c2-rCX" firstAttribute="leading" secondItem="iN0-l3-epB" secondAttribute="leading" constant="20" symbolic="YES" id="fvb-Df-36g"/>
             </constraints>
             <nil key="simulatedStatusBarMetrics"/>
diff --git a/Example/RxFireAuth/Base.lproj/Main.storyboard b/Example/RxFireAuth/Base.lproj/Main.storyboard
index 7caa05b..1c2810b 100644
--- a/Example/RxFireAuth/Base.lproj/Main.storyboard
+++ b/Example/RxFireAuth/Base.lproj/Main.storyboard
@@ -11,7 +11,7 @@
         <scene sceneID="Nug-Yv-kp9">
             <objects>
                 <tableViewController id="ctm-QS-frk" customClass="ViewController" customModule="RxFireAuth_Example" customModuleProvider="target" sceneMemberID="viewController">
-                    <tableView key="view" clipsSubviews="YES" contentMode="scaleToFill" alwaysBounceVertical="YES" dataMode="static" style="grouped" separatorStyle="default" rowHeight="-1" estimatedRowHeight="-1" sectionHeaderHeight="18" estimatedSectionHeaderHeight="-1" sectionFooterHeight="18" estimatedSectionFooterHeight="-1" id="oh8-fu-n4g">
+                    <tableView key="view" clipsSubviews="YES" contentMode="scaleToFill" alwaysBounceVertical="YES" dataMode="static" style="grouped" separatorStyle="default" allowsSelection="NO" rowHeight="-1" estimatedRowHeight="-1" sectionHeaderHeight="18" estimatedSectionHeaderHeight="-1" sectionFooterHeight="18" estimatedSectionFooterHeight="-1" id="oh8-fu-n4g">
                         <rect key="frame" x="0.0" y="0.0" width="375" height="667"/>
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
                         <color key="backgroundColor" cocoaTouchSystemColor="groupTableViewBackgroundColor"/>
@@ -249,6 +249,39 @@
                                             </constraints>
                                         </tableViewCellContentView>
                                     </tableViewCell>
+                                    <tableViewCell clipsSubviews="YES" contentMode="scaleToFill" preservesSuperviewLayoutMargins="YES" selectionStyle="default" indentationWidth="10" id="qlR-qY-KKn">
+                                        <rect key="frame" x="0.0" y="726.5" width="375" height="43.5"/>
+                                        <autoresizingMask key="autoresizingMask"/>
+                                        <tableViewCellContentView key="contentView" opaque="NO" clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="center" preservesSuperviewLayoutMargins="YES" insetsLayoutMarginsFromSafeArea="NO" tableViewCell="qlR-qY-KKn" id="q27-43-Ymq">
+                                            <rect key="frame" x="0.0" y="0.0" width="375" height="43.5"/>
+                                            <autoresizingMask key="autoresizingMask"/>
+                                            <subviews>
+                                                <stackView opaque="NO" contentMode="scaleToFill" alignment="center" spacing="8" translatesAutoresizingMaskIntoConstraints="NO" id="Rcq-UE-Qbr">
+                                                    <rect key="frame" x="20" y="0.0" width="335" height="44"/>
+                                                    <subviews>
+                                                        <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="Reset Anonymous user after logout" textAlignment="natural" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontForContentSizeCategory="YES" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="Fu5-pU-8gN">
+                                                            <rect key="frame" x="0.0" y="12" width="278" height="20.5"/>
+                                                            <fontDescription key="fontDescription" style="UICTFontTextStyleBody"/>
+                                                            <nil key="textColor"/>
+                                                            <nil key="highlightedColor"/>
+                                                        </label>
+                                                        <switch opaque="NO" contentMode="scaleToFill" horizontalHuggingPriority="750" verticalHuggingPriority="750" contentHorizontalAlignment="center" contentVerticalAlignment="center" on="YES" translatesAutoresizingMaskIntoConstraints="NO" id="mot-Jo-eYh">
+                                                            <rect key="frame" x="286" y="6.5" width="51" height="31"/>
+                                                        </switch>
+                                                    </subviews>
+                                                    <constraints>
+                                                        <constraint firstAttribute="height" constant="44" id="Lg7-24-mHV"/>
+                                                    </constraints>
+                                                </stackView>
+                                            </subviews>
+                                            <constraints>
+                                                <constraint firstItem="Rcq-UE-Qbr" firstAttribute="top" secondItem="q27-43-Ymq" secondAttribute="top" id="4PU-rW-i69"/>
+                                                <constraint firstAttribute="trailing" secondItem="Rcq-UE-Qbr" secondAttribute="trailing" constant="20" symbolic="YES" id="cGu-zo-oVi"/>
+                                                <constraint firstAttribute="bottom" secondItem="Rcq-UE-Qbr" secondAttribute="bottom" id="iN0-nC-VDh"/>
+                                                <constraint firstItem="Rcq-UE-Qbr" firstAttribute="leading" secondItem="q27-43-Ymq" secondAttribute="leading" constant="20" symbolic="YES" id="zFY-xm-Cl3"/>
+                                            </constraints>
+                                        </tableViewCellContentView>
+                                    </tableViewCell>
                                 </cells>
                             </tableViewSection>
                         </sections>
@@ -262,6 +295,7 @@
                         <outlet property="loginField" destination="hRm-F9-3g3" id="HaC-Kz-FKX"/>
                         <outlet property="nameField" destination="xXd-3v-zRi" id="igw-fT-jDW"/>
                         <outlet property="passwordField" destination="FMT-pY-asG" id="7Ay-uj-9lj"/>
+                        <outlet property="resetAnononymousSwitch" destination="mot-Jo-eYh" id="ehW-PG-2Xf"/>
                         <outlet property="signInButton" destination="zK6-No-yaf" id="vsj-Ee-aWa"/>
                         <outlet property="signOutButton" destination="ftK-wu-fHt" id="ia4-38-0BB"/>
                         <outlet property="subtitleLabel" destination="8n1-U7-jzB" id="3NJ-4x-Yid"/>
diff --git a/Example/RxFireAuth/ViewController.swift b/Example/RxFireAuth/ViewController.swift
index f9dea04..01bca72 100644
--- a/Example/RxFireAuth/ViewController.swift
+++ b/Example/RxFireAuth/ViewController.swift
@@ -27,6 +27,8 @@ class ViewController: UITableViewController {
     @IBOutlet weak var nameField: UITextField!
     @IBOutlet weak var updateProfileButton: UIButton!
     
+    @IBOutlet weak var resetAnononymousSwitch: UISwitch!
+    
     private var userManager: UserManagerType = UserManager()
     private var disposeBag = DisposeBag()
     
@@ -50,12 +52,10 @@ class ViewController: UITableViewController {
                         }
                         self.subtitleLabel.text = "You are logged-in with \(user.email ?? "unknown")."
                     }
-                    self.signOutButton.isEnabled = true
                     self.nameField.text = user.displayName
                 } else {
                     self.welcomeLabel.text = "Welcome!"
                     self.subtitleLabel.text = "You are not logged-in."
-                    self.signOutButton.isEnabled = false
                 }
             }).disposed(by: self.disposeBag)
         
@@ -123,7 +123,7 @@ class ViewController: UITableViewController {
     
     @IBAction func signOut(sender: AnyObject) {
         self.toggleProgress(true)
-        self.userManager.logout(resetToAnonymous: false)
+        self.userManager.logout(resetToAnonymous: self.resetAnononymousSwitch.isOn)
             .subscribe(onCompleted: {
                 self.toggleProgress(false)
             }, onError: self.show(error:))
diff --git a/RxFireAuth/Classes/UserError.swift b/RxFireAuth/Classes/UserError.swift
index 46b299d..d83d0cf 100644
--- a/RxFireAuth/Classes/UserError.swift
+++ b/RxFireAuth/Classes/UserError.swift
@@ -22,6 +22,38 @@ public enum UserError: LocalizedError {
     case invalidEmail
     /// The action would require to migrate the current user data to a new account.
     case migrationRequired
+    /// The requested action cannot be performed because there is already an anonymous user logged-in.
+    case alreadyAnonymous
+    /// The specified user cannot be found.
+    case userNotFound
+    /// The specified user is disabled.
+    case userDisabled
+    /// The user token has expired.
+    case expiredToken
+    /// The specified password is invalid.
+    case wrongPassword
+    /// The specified credential is either expired or invalid.
+    case invalidCredential
+    /// The specified email is already in use in another account.
+    case emailAlreadyInUse
+    /// The specified password does not satisfy the basic security requirements.
+    case weakPassword(String?)
+    /// The requested action would target a different user than the one currently signed-in.
+    case wrongUser
+    /// The requested action requires a recent call to `self.confirmAuthentication(email:password:)`.
+    case authenticationConfirmationRequired
+    /// The specified provider is already linked with this user.
+    case providerAlreadyLinked
+    /// An error occurred while reaching Firebase servers.
+    case networkError
+    /// The requested operation is not enabled in Firebase Console.
+    case configurationError
+    /// The provided Firebase configuration is invalid.
+    case invalidConfiguration
+    /// An error occurred while attempting to access the keychain.
+    case keychainError(Error?)
+    /// An unknown error has occurred.
+    case unknown(Error?)
     
     public var errorDescription: String? {
         switch self {
@@ -35,21 +67,38 @@ public enum UserError: LocalizedError {
             return "The provided email address is invalid."
         case .migrationRequired:
             return "Proceeding with this action requires confirmation to migrate data from a user account to another."
-        }
-    }
-    
-    public var failureReason: String? {
-        switch self {
-        case .noUser:
-            return "There is no user currently logged-in."
-        case .invalidUpdate:
-            return "The update contains invalid data and cannot be performed."
-        case .alreadyLoggedIn:
-            return "The requested action can be performed only when there is an anonymous user or nobody logged-in."
-        case .invalidEmail:
-            return "The provided value is not a valid email address."
-        case .migrationRequired:
-            return "The requested action will result in deleting the currently logged-in user and replace it with another user account, hence the library is asking for confirmation that the caller will perform (or not) data migration."
+        case .alreadyAnonymous:
+            return "There is already an anonymous user logged-in."
+        case .userNotFound:
+            return "The specified user cannot be found."
+        case .networkError:
+            return "A network error occurred."
+        case .unknown(let error):
+            return error?.localizedDescription ?? "An unknown error occurred."
+        case .userDisabled:
+            return "The specified user is disabled."
+        case .expiredToken:
+            return "The credential stored on this device are no longer valid. Please re-authenticate."
+        case .wrongPassword:
+            return "The specified password is invalid."
+        case .invalidCredential:
+            return "The specified credential is invalid."
+        case .emailAlreadyInUse:
+            return "This email address is already registered with another account."
+        case .weakPassword(let reason):
+            return "The provided password does not satisfy the security requirements: \(reason ?? "please try again")."
+        case .wrongUser:
+            return "You are authenticating with a different user."
+        case .authenticationConfirmationRequired:
+            return "In order to perform this action, you'll have to confirm your credentials by authenticating again."
+        case .providerAlreadyLinked:
+            return "This login provider is already linked."
+        case .configurationError:
+            return "There is an error in your Firebase Console configuration."
+        case .invalidConfiguration:
+            return "There is an error in your app configuration."
+        case .keychainError(let error):
+            return "An error occurred while comunicating with the keychain: \(error?.localizedDescription ?? "unknown")"
         }
     }
     
diff --git a/RxFireAuth/Classes/UserManager.swift b/RxFireAuth/Classes/UserManager.swift
index 0beb547..4c76a78 100644
--- a/RxFireAuth/Classes/UserManager.swift
+++ b/RxFireAuth/Classes/UserManager.swift
@@ -43,6 +43,10 @@ public class UserManager: UserManagerType {
         return Auth.auth().currentUser != nil && !Auth.auth().currentUser!.isAnonymous
     }
     
+    public var isAnonymous: Bool {
+        return Auth.auth().currentUser != nil && Auth.auth().currentUser!.isAnonymous
+    }
+    
     public var user: UserData? {
         if let user = Auth.auth().currentUser {
             return UserData(id: user.uid, email: user.email, displayName: user.displayName, isAnonymous: user.isAnonymous)
@@ -89,15 +93,15 @@ public class UserManager: UserManagerType {
     }
     
     public func accountExists(with email: String) -> Single<Bool> {
-        return Single.create { (observer) -> Disposable in
+        return Single.create { [unowned self] (observer) -> Disposable in
             let disposable = Disposables.create { }
             
-            Auth.auth().fetchSignInMethods(forEmail: email) { (methods,
+            Auth.auth().fetchSignInMethods(forEmail: email) { [unowned self] (methods,
                 error) in
                 guard !disposable.isDisposed else { return }
                 
                 if let error = error {
-                    observer(.error(error))
+                    observer(.error(self.map(error: error)))
                 } else if let methods = methods, methods.count > 0 {
                     observer(.success(true))
                 } else {
@@ -110,95 +114,104 @@ public class UserManager: UserManagerType {
     }
     
     public func register(email: String, password: String) -> Completable {
-        guard !self.isLoggedIn else { return .error(UserError.alreadyLoggedIn) }
-        
-        if Auth.auth().currentUser?.isAnonymous == true {
-            return self.linkAnonymousAccount(toEmail: email, password: password)
-        }
-        
-        return Completable.create { (observer) -> Disposable in
-            let disposable = Disposables.create { }
+        return Completable.deferred { [unowned self] in
+            guard !self.isLoggedIn else { return .error(UserError.alreadyLoggedIn) }
             
-            Auth.auth().createUser(withEmail: email, password: password) { (_, error) in
-                guard !disposable.isDisposed else { return }
-                if let error = error {
-                    observer(.error(error))
-                } else {
-                    observer(.completed)
-                }
+            if Auth.auth().currentUser?.isAnonymous == true {
+                return self.linkAnonymousAccount(toEmail: email, password: password)
             }
             
-            return disposable
+            return Completable.create { (observer) -> Disposable in
+                let disposable = Disposables.create { }
+                
+                Auth.auth().createUser(withEmail: email, password: password) { (_, error) in
+                    guard !disposable.isDisposed else { return }
+                    if let error = error {
+                        observer(.error(self.map(error: error)))
+                    } else {
+                        observer(.completed)
+                    }
+                }
+                
+                return disposable
+            }
         }
     }
     
     public func loginAnonymously() -> Completable {
-        guard !isLoggedIn else { return Completable.error(UserError.alreadyLoggedIn) }
-        
-        return Completable.create { (observer) -> Disposable in
-            let disposable = Disposables.create { }
+        return Completable.deferred { [unowned self] in
+            guard !self.isLoggedIn else { return .error(UserError.alreadyLoggedIn) }
+            guard !self.isAnonymous else { return .error(UserError.alreadyAnonymous) }
             
-            Auth.auth().signInAnonymously { (_, error) in
-                guard !disposable.isDisposed else { return }
-                if let error = error {
-                    observer(.error(error))
-                } else {
-                    observer(.completed)
+            return Completable.create { [unowned self] (observer) -> Disposable in
+                let disposable = Disposables.create { }
+                
+                Auth.auth().signInAnonymously { [unowned self] (_, error) in
+                    guard !disposable.isDisposed else { return }
+                    if let error = error {
+                        observer(.error(self.map(error: error)))
+                    } else {
+                        observer(.completed)
+                    }
                 }
+                
+                return disposable
             }
-            
-            return disposable
         }
     }
     
     public func linkAnonymousAccount(toEmail email: String, password: String) -> Completable {
-        guard let user = Auth.auth().currentUser, user.isAnonymous else { return Completable.error(UserError.noUser) }
-        
-        return Completable.create { (observer) -> Disposable in
-            let disposable = Disposables.create { }
+        return Completable.deferred {
+            guard let user = Auth.auth().currentUser, user.isAnonymous else { return .error(UserError.noUser) }
             
-            let credential = EmailAuthProvider.credential(withEmail: email, password: password)
-            user.link(with: credential) { (_, error) in
-                guard !disposable.isDisposed else { return }
-                if let error = error {
-                    observer(.error(error))
-                } else {
-                    self.forceRefreshAutoUpdatingUser.onNext(())
-                    observer(.completed)
+            return Completable.create { [unowned self] (observer) -> Disposable in
+                let disposable = Disposables.create { }
+                
+                let credential = EmailAuthProvider.credential(withEmail: email, password: password)
+                user.link(with: credential) { (_, error) in
+                    guard !disposable.isDisposed else { return }
+                    if let error = error {
+                        observer(.error(self.map(error: error)))
+                    } else {
+                        self.forceRefreshAutoUpdatingUser.onNext(())
+                        observer(.completed)
+                    }
                 }
+                
+                return disposable
             }
-            
-            return disposable
         }
     }
     
     public func login(email: String, password: String, allowMigration: Bool?) -> Single<LoginDescriptor> {
-        guard !self.isLoggedIn else { return .error(UserError.alreadyLoggedIn) }
-        
-        return self.accountExists(with: email)
-            .flatMap { (accountExists) -> Single<LoginDescriptor> in
-                if accountExists {
-                    return self.loginWithoutChecking(email: email, password: password, allowMigration: allowMigration)
-                } else {
-                    return self.register(email: email, password: password)
-                        .andThen(
-                            Single.just(
-                                LoginDescriptor(fullName: nil, performMigration: false, oldUserId: nil, newUserId: self.user?.id)
+        return Single.deferred { [unowned self] in
+            guard !self.isLoggedIn else { return .error(UserError.alreadyLoggedIn) }
+            
+            return self.accountExists(with: email)
+                .flatMap { (accountExists) -> Single<LoginDescriptor> in
+                    if accountExists {
+                        return self.loginWithoutChecking(email: email, password: password, allowMigration: allowMigration)
+                    } else {
+                        return self.register(email: email, password: password)
+                            .andThen(
+                                Single.just(
+                                    LoginDescriptor(fullName: nil, performMigration: false, oldUserId: nil, newUserId: self.user?.id)
+                                )
                             )
-                        )
+                    }
                 }
-            }
+        }
     }
     
     public func loginWithoutChecking(email: String, password: String, allowMigration: Bool?) -> Single<LoginDescriptor> {
-        return Single.create { (observer) -> Disposable in
+        return Single.create { [unowned self] (observer) -> Disposable in
             let disposable = Disposables.create { }
             
             var oldUserId: String?
             
-            let signInCompletionHandler: (Error?) -> Void = { (error) in
+            let signInCompletionHandler: (Error?) -> Void = { [unowned self] (error) in
                 if let error = error {
-                    observer(.error(error))
+                    observer(.error(self.map(error: error)))
                 } else if let newUser = Auth.auth().currentUser {
                     observer(.success(
                             LoginDescriptor(
@@ -222,9 +235,9 @@ public class UserManager: UserManagerType {
                 
                 oldUserId = currentUser.uid
                 
-                currentUser.delete { (error) in
+                currentUser.delete { [unowned self] (error) in
                     if let error = error {
-                        observer(.error(error))
+                        observer(.error(self.map(error: error)))
                     } else {
                         self.signIn(with: EmailAuthProvider.credential(withEmail: email, password: password), in: disposable, completionHandler: signInCompletionHandler)
                     }
@@ -261,94 +274,153 @@ public class UserManager: UserManagerType {
     }
     
     public func logout(resetToAnonymous: Bool = false) -> Completable {
-        var logoutAction = Completable.create { (observer) -> Disposable in
-            let disposable = Disposables.create { }
+        return Completable.deferred { [unowned self] in
+            if resetToAnonymous && self.isAnonymous { return .error(UserError.alreadyAnonymous) }
             
-            do {
-                try Auth.auth().signOut()
-                observer(.completed)
-            } catch {
-                observer(.error(error))
+            var logoutAction = Completable.create { (observer) -> Disposable in
+                let disposable = Disposables.create { }
+                
+                do {
+                    try Auth.auth().signOut()
+                    observer(.completed)
+                } catch {
+                    observer(.error(self.map(error: error)))
+                }
+                
+                return disposable
             }
             
-            return disposable
-        }
-        
-        if (resetToAnonymous) {
-            logoutAction = logoutAction
-                .andThen(self.loginAnonymously())
+            if (resetToAnonymous) {
+                logoutAction = logoutAction
+                    .andThen(self.loginAnonymously())
+            }
+            
+            return logoutAction
         }
-        
-        return logoutAction
     }
     
     public func update(user: UserData) -> Completable {
-        guard let currentUser = Auth.auth().currentUser else { return Completable.error(UserError.noUser) }
-        
-        return Completable.create { (observer) -> Disposable in
-            let disposable = Disposables.create { }
+        return Completable.deferred { [unowned self] in
+            guard let currentUser = Auth.auth().currentUser else { return Completable.error(UserError.noUser) }
             
-            let changeRequest = currentUser.createProfileChangeRequest()
-            changeRequest.displayName = user.displayName
-            
-            changeRequest.commitChanges { (error) in
-                if let error = error {
-                    observer(.error(error))
-                } else {
-                    self.forceRefreshAutoUpdatingUser.onNext(())
-                    observer(.completed)
+            return Completable.create { [unowned self] (observer) -> Disposable in
+                let disposable = Disposables.create { }
+                
+                let changeRequest = currentUser.createProfileChangeRequest()
+                changeRequest.displayName = user.displayName
+                
+                changeRequest.commitChanges { (error) in
+                    if let error = error {
+                        observer(.error(self.map(error: error)))
+                    } else {
+                        self.forceRefreshAutoUpdatingUser.onNext(())
+                        observer(.completed)
+                    }
                 }
+                
+                return disposable
             }
-            
-            return disposable
         }
     }
     
     public func update(userConfigurationHandler: @escaping (UserData) -> UserData) -> Completable {
-        guard Auth.auth().currentUser != nil else { return Completable.error(UserError.noUser) }
-        
-        return self.autoupdatingUser
-            .take(1)
-            .filter { $0 != nil }.map { $0! }
-            .map(userConfigurationHandler)
-            .flatMap { self.update(user: $0) }
-            .asCompletable()
+        return Completable.deferred { [unowned self] in
+            guard Auth.auth().currentUser != nil else { return Completable.error(UserError.noUser) }
+            
+            return self.autoupdatingUser
+                .take(1)
+                .filter { $0 != nil }.map { $0! }
+                .map(userConfigurationHandler)
+                .flatMap { [unowned self] in self.update(user: $0) }
+                .asCompletable()
+        }
     }
     
     public func updateEmail(newEmail: String) -> Completable {
-        guard let user = Auth.auth().currentUser else { return Completable.error(UserError.noUser) }
-        
-        return Completable.create { (observer) -> Disposable in
-            let disposable = Disposables.create { }
+        return Completable.deferred { [unowned self] in
+            guard let user = Auth.auth().currentUser else { return Completable.error(UserError.noUser) }
             
-            user.updateEmail(to: newEmail) { (error) in
-                if let error = error {
-                    observer(.error(error))
-                } else {
-                    observer(.completed)
+            return Completable.create { (observer) -> Disposable in
+                let disposable = Disposables.create { }
+                
+                user.updateEmail(to: newEmail) { (error) in
+                    if let error = error {
+                        observer(.error(self.map(error: error)))
+                    } else {
+                        observer(.completed)
+                    }
                 }
+                
+                return disposable
             }
-            
-            return disposable
         }
     }
     
     public func confirmAuthentication(email: String, password: String) -> Completable {
-        guard let user = Auth.auth().currentUser else { return Completable.error(UserError.noUser) }
-        
-        return Completable.create { (observer) -> Disposable in
-            let disposable = Disposables.create { }
+        return Completable.deferred { [unowned self] in
+            guard let user = Auth.auth().currentUser else { return Completable.error(UserError.noUser) }
             
-            user.reauthenticate(with: EmailAuthProvider.credential(withEmail: email, password: password)) { (result, error) in
-                guard !disposable.isDisposed else { return }
-                if let error = error {
-                    observer(.error(error))
-                } else {
-                    observer(.completed)
+            return Completable.create { (observer) -> Disposable in
+                let disposable = Disposables.create { }
+                
+                user.reauthenticate(with: EmailAuthProvider.credential(withEmail: email, password: password)) { [unowned self] (result, error) in
+                    guard !disposable.isDisposed else { return }
+                    if let error = error {
+                        observer(.error(self.map(error: error)))
+                    } else {
+                        observer(.completed)
+                    }
                 }
+                
+                return disposable
             }
-            
-            return disposable
+        }
+    }
+    
+    /// Map a generic error to a `UserError`.
+    ///
+    /// For more info on all the Firebase errors,
+    /// refer to the [Firebase Documentation](https://firebase.google.com/docs/auth/ios/errors)
+    ///
+    /// - parameters:
+    ///     - error: A error.
+    /// - returns: A `UserError` wrapping the error.
+    func map(error: Error) -> UserError {
+        let nsError = error as NSError
+        
+        switch nsError.code {
+        case AuthErrorCode.networkError.rawValue:
+            return .networkError
+        case AuthErrorCode.userNotFound.rawValue:
+            return .userNotFound
+        case AuthErrorCode.userTokenExpired.rawValue:
+            return .expiredToken
+        case AuthErrorCode.invalidEmail.rawValue:
+            return .invalidEmail
+        case AuthErrorCode.userDisabled.rawValue:
+            return .userDisabled
+        case AuthErrorCode.wrongPassword.rawValue:
+            return .wrongPassword
+        case AuthErrorCode.invalidCredential.rawValue:
+            return .invalidCredential
+        case AuthErrorCode.emailAlreadyInUse.rawValue:
+            return .emailAlreadyInUse
+        case AuthErrorCode.operationNotAllowed.rawValue:
+            return .configurationError
+        case AuthErrorCode.invalidAPIKey.rawValue, AuthErrorCode.appNotAuthorized.rawValue, AuthErrorCode.appNotVerified.rawValue:
+            return .invalidConfiguration
+        case AuthErrorCode.weakPassword.rawValue:
+            return .weakPassword(nsError.userInfo[NSLocalizedFailureReasonErrorKey] as? String)
+        case AuthErrorCode.keychainError.rawValue:
+            return .keychainError(error)
+        case AuthErrorCode.userMismatch.rawValue:
+            return .wrongUser
+        case AuthErrorCode.requiresRecentLogin.rawValue:
+            return .authenticationConfirmationRequired
+        case AuthErrorCode.providerAlreadyLinked.rawValue:
+            return .providerAlreadyLinked
+        default:
+            return .unknown(error)
         }
     }
     
diff --git a/RxFireAuth/Classes/UserManagerType.swift b/RxFireAuth/Classes/UserManagerType.swift
index 4927160..20cb1ac 100644
--- a/RxFireAuth/Classes/UserManagerType.swift
+++ b/RxFireAuth/Classes/UserManagerType.swift
@@ -15,11 +15,17 @@ import RxSwift
 /// When using the library in your code always make sure to
 /// reference this protocol instead of the default implementation `UserManager`,
 /// as this protocol will always conform to Semantic Versioning.
+///
+/// All methods of this protocol are wrapped inside a Rx object that
+/// will not execute any code until somebody subscribes to it.
 public protocol UserManagerType {
     
     /// Get if there is a currently logged-in user.
     var isLoggedIn: Bool { get }
     
+    /// Get if there is an anonymous user logged-in.
+    var isAnonymous: Bool { get }
+    
     /// Get the currently logged-in user or nil if no user is logged-in.
     var user: UserData? { get }
     
@@ -86,8 +92,12 @@ public protocol UserManagerType {
     
     /// Logout the currently logged-in user.
     ///
+    /// Using the `resetToAnonymous` parameter, you can make sure
+    /// that there is always a user signed in.
+    ///
     /// - parameters:
-    ///     - resetToAnonymous: If true, after having logged-out successfully, this function will immediately sign in a new anonymous user.
+    ///     - resetToAnonymous: If `true`, after having logged-out successfully, this function will immediately sign in a new anonymous user.
+    /// - throws:
     /// - returns: A Completable action to observe.
     func logout(resetToAnonymous: Bool) -> Completable