feat: Provider Models (AuthProvider + concrete types) (#2223)

* feat: added preconditions for specific auth provider configurations

* test: covers auth providers with config validations

* fix: auth provider validation and tests

- validate serverClientId empty string
- validate applicationId empty string
- remove @test(expected=) not descriptive
- tests covering AuthProviders Google and Facebook config validation

Author: demolaf

auth/src/main/java/com/firebase/ui/auth/compose/configuration/AuthProvider.kt

@@ -14,8 +14,15 @@
 
 package com.firebase.ui.auth.compose.configuration
 
+import android.content.Context
 import android.graphics.Color
+import android.util.Log
 import androidx.compose.ui.graphics.vector.ImageVector
+import com.firebase.ui.auth.AuthUI
+import com.firebase.ui.auth.R
+import com.firebase.ui.auth.util.Preconditions
+import com.firebase.ui.auth.util.data.PhoneNumberUtils
+import com.firebase.ui.auth.util.data.ProviderAvailability
 import com.google.firebase.auth.ActionCodeSettings
 import com.google.firebase.auth.EmailAuthProvider
 import com.google.firebase.auth.FacebookAuthProvider
@@ -78,6 +85,14 @@ abstract class AuthProvider(open val providerId: String) {
          */
         val isEmailLinkSignInEnabled: Boolean = false,
 
+        /**
+         * Forces email link sign-in to complete on the same device that initiated it.
+         *
+         * When enabled, prevents email links from being opened on different devices,
+         * which is required for security when upgrading anonymous users. Defaults to true.
+         */
+        val isEmailLinkForceSameDeviceEnabled: Boolean = true,
+
         /**
          * Settings for email link actions.
          */
@@ -100,11 +115,10 @@ abstract class AuthProvider(open val providerId: String) {
     ) : AuthProvider(providerId = Provider.EMAIL.id) {
         fun validate() {
             if (isEmailLinkSignInEnabled) {
-                val actionCodeSettings = actionCodeSettings
-                    ?: requireNotNull(actionCodeSettings) {
-                        "ActionCodeSettings cannot be null when using " +
-                                "email link sign in."
-                    }
+                val actionCodeSettings = requireNotNull(actionCodeSettings) {
+                    "ActionCodeSettings cannot be null when using " +
+                            "email link sign in."
+                }
 
                 check(actionCodeSettings.canHandleCodeInApp()) {
                     "You must set canHandleCodeInApp in your " +
@@ -118,6 +132,11 @@ abstract class AuthProvider(open val providerId: String) {
      * Phone number authentication provider configuration.
      */
     class Phone(
+        /**
+         * The phone number in international format.
+         */
+        val defaultNumber: String?,
+
         /**
          * The default country code to pre-select.
          */
@@ -147,7 +166,31 @@ abstract class AuthProvider(open val providerId: String) {
          * Enables automatic retrieval of the SMS code. Defaults to true.
          */
         val isAutoRetrievalEnabled: Boolean = true
-    ) : AuthProvider(providerId = Provider.PHONE.id)
+    ) : AuthProvider(providerId = Provider.PHONE.id) {
+        fun validate() {
+            defaultNumber?.let {
+                check(PhoneNumberUtils.isValid(it)) {
+                    "Invalid phone number: $it"
+                }
+            }
+
+            defaultCountryCode?.let {
+                check(PhoneNumberUtils.isValidIso(it)) {
+                    "Invalid country iso: $it"
+                }
+            }
+
+            allowedCountries?.forEach { code ->
+                check(
+                    PhoneNumberUtils.isValidIso(code) ||
+                            PhoneNumberUtils.isValid(code)
+                ) {
+                    "Invalid input: You must provide a valid country iso (alpha-2) " +
+                            "or code (e-164). e.g. 'us' or '+1'. Invalid code: $code"
+                }
+            }
+        }
+    }
 
     /**
      * Google Sign-In provider configuration.
@@ -186,12 +229,40 @@ abstract class AuthProvider(open val providerId: String) {
         providerId = Provider.GOOGLE.id,
         scopes = scopes,
         customParameters = customParameters
-    )
+    ) {
+        fun validate(context: Context) {
+            if (serverClientId == null) {
+                Preconditions.checkConfigured(
+                    context,
+                    "Check your google-services plugin configuration, the" +
+                            " default_web_client_id string wasn't populated.",
+                    R.string.default_web_client_id
+                )
+            } else {
+                require(serverClientId.isNotBlank()) {
+                    "Server client ID cannot be blank."
+                }
+            }
+
+            val hasEmailScope = scopes.contains("email")
+            if (!hasEmailScope) {
+                Log.w(
+                    "AuthProvider.Google",
+                    "The scopes do not include 'email'. In most cases this is a mistake!"
+                )
+            }
+        }
+    }
 
     /**
      * Facebook Login provider configuration.
      */
     class Facebook(
+        /**
+         * The Facebook application ID.
+         */
+        val applicationId: String? = null,
+
         /**
          * The list of scopes (permissions) to request. Defaults to email and public_profile.
          */
@@ -210,7 +281,30 @@ abstract class AuthProvider(open val providerId: String) {
         providerId = Provider.FACEBOOK.id,
         scopes = scopes,
         customParameters = customParameters
-    )
+    ) {
+        fun validate(context: Context) {
+            if (!ProviderAvailability.IS_FACEBOOK_AVAILABLE) {
+                throw RuntimeException(
+                    "Facebook provider cannot be configured " +
+                            "without dependency. Did you forget to add " +
+                            "'com.facebook.android:facebook-login:VERSION' dependency?"
+                )
+            }
+
+            if (applicationId == null) {
+                Preconditions.checkConfigured(
+                    context,
+                    "Facebook provider unconfigured. Make sure to " +
+                            "add a `facebook_application_id` string or provide applicationId parameter.",
+                    R.string.facebook_application_id
+                )
+            } else {
+                require(applicationId.isNotBlank()) {
+                    "Facebook application ID cannot be blank"
+                }
+            }
+        }
+    }
 
     /**
      * Twitter/X authentication provider configuration.
@@ -314,7 +408,16 @@ abstract class AuthProvider(open val providerId: String) {
     /**
      * Anonymous authentication provider. It has no configurable properties.
      */
-    object Anonymous : AuthProvider(providerId = Provider.ANONYMOUS.id)
+    object Anonymous : AuthProvider(providerId = Provider.ANONYMOUS.id) {
+        fun validate(providers: List<AuthProvider>) {
+            if (providers.size == 1 && providers.first() is Anonymous) {
+                throw IllegalStateException(
+                    "Sign in as guest cannot be the only sign in method. " +
+                            "In this case, sign the user in anonymously your self; no UI is needed."
+                )
+            }
+        }
+    }
 
     /**
      * A generic OAuth provider for any unsupported provider.
@@ -353,5 +456,15 @@ abstract class AuthProvider(open val providerId: String) {
         providerId = providerId,
         scopes = scopes,
         customParameters = customParameters
-    )
+    ) {
+        fun validate() {
+            require(providerId.isNotBlank()) {
+                "Provider ID cannot be null or empty"
+            }
+
+            require(buttonLabel.isNotBlank()) {
+                "Button label cannot be null or empty"
+            }
+        }
+    }
 }

auth/src/main/java/com/firebase/ui/auth/compose/configuration/AuthUIConfiguration.kt

@@ -68,12 +68,7 @@ class AuthUIConfigurationBuilder {
         }
 
         // Cannot have only anonymous provider
-        if (providers.size == 1 && providers.first() is AuthProvider.Anonymous) {
-            throw IllegalStateException(
-                "Sign in as guest cannot be the only sign in method. " +
-                        "In this case, sign the user in anonymously your self; no UI is needed."
-            )
-        }
+        AuthProvider.Anonymous.validate(providers)
 
         // Check for duplicate providers
         val providerIds = providers.map { it.providerId }
@@ -89,7 +84,21 @@ class AuthUIConfigurationBuilder {
         // Provider specific validations
         providers.forEach { provider ->
             when (provider) {
-                is AuthProvider.Email -> provider.validate()
+                is AuthProvider.Email -> {
+                    provider.validate()
+
+                    if (isAnonymousUpgradeEnabled && provider.isEmailLinkSignInEnabled) {
+                        check(provider.isEmailLinkForceSameDeviceEnabled) {
+                            "You must force the same device flow when using email link sign in " +
+                                    "with anonymous user upgrade"
+                        }
+                    }
+                }
+
+                is AuthProvider.Phone -> provider.validate()
+                is AuthProvider.Google -> provider.validate(context)
+                is AuthProvider.Facebook -> provider.validate(context)
+                is AuthProvider.GenericOAuth -> provider.validate()
                 else -> null
             }
         }