[fenix] For https://github.com/mozilla-mobile/fenix/issues/19797 - New FenixAccountManager#getAccountState()

This new method allows a single source of truth for getting the up-to-date
account status without clients interesting in this needing to know what to
check for.

app/src/main/java/org/mozilla/fenix/components/accounts/FenixAccountManager.kt

@@ -21,6 +21,20 @@ open class FenixAccountManager(context: Context) {
     val accountProfileEmail
         get() = accountManager.accountProfile()?.email
 
+    /**
+     * The current state of the Firefox Account. See [AccountState].
+     */
+    val accountState: AccountState
+        get() = if (accountManager.authenticatedAccount() == null) {
+            AccountState.NO_ACCOUNT
+        } else {
+            if (accountManager.accountNeedsReauth()) {
+                AccountState.NEEDS_REAUTHENTICATION
+            } else {
+                AccountState.AUTHENTICATED
+            }
+        }
+
     /**
      * Check if the current account is signed in and authenticated.
      */
@@ -31,3 +45,23 @@ open class FenixAccountManager(context: Context) {
         return account != null && !needsReauth
     }
 }
+
+/**
+ * General states as an overview of the current Firefox Account.
+ */
+enum class AccountState {
+    /**
+     * There is no known Firefox Account.
+     */
+    NO_ACCOUNT,
+
+    /**
+     * A Firefox Account exists but needs to be re-authenticated.
+     */
+    NEEDS_REAUTHENTICATION,
+
+    /**
+     * A Firefox Account exists and the user is currently signed into it.
+     */
+    AUTHENTICATED,
+}

app/src/test/java/org/mozilla/fenix/components/accounts/FenixAccountManagerTest.kt

@@ -12,6 +12,7 @@ import mozilla.components.concept.sync.Profile
 import mozilla.components.service.fxa.manager.FxaAccountManager
 import org.junit.Assert.assertEquals
 import org.junit.Assert.assertFalse
+import org.junit.Assert.assertSame
 import org.junit.Assert.assertTrue
 import org.junit.Before
 import org.junit.Test
@@ -98,4 +99,45 @@ class FenixAccountManagerTest {
         val signedIn = fenixFxaManager.signedInToFxa()
         assertFalse(signedIn)
     }
+
+    @Test
+    fun `GIVEN no account exists WHEN accountState is called THEN it returns AccountState#NO_ACCOUNT`() {
+        every { context.components.backgroundServices.accountManager } returns accountManagerComponent
+        every { accountManagerComponent.authenticatedAccount() } returns null
+        fenixFxaManager = FenixAccountManager(context)
+
+        assertSame(AccountState.NO_ACCOUNT, fenixFxaManager.accountState)
+
+        // No account but signed in should not be possible. Test protecting against such a regression.
+        every { accountManagerComponent.accountNeedsReauth() } returns false
+        assertSame(AccountState.NO_ACCOUNT, fenixFxaManager.accountState)
+
+        // No account and signed out still means no account. Test protecting against such a regression.
+        every { accountManagerComponent.accountNeedsReauth() } returns true
+        assertSame(AccountState.NO_ACCOUNT, fenixFxaManager.accountState)
+    }
+
+    @Test
+    fun `GIVEN an account exists but needs to be re-authenticated WHEN accountState is called THEN it returns AccountState#NEEDS_REAUTHENTICATION`() {
+        every { context.components.backgroundServices.accountManager } returns accountManagerComponent
+        every { accountManagerComponent.authenticatedAccount() } returns mockk()
+        every { accountManagerComponent.accountNeedsReauth() } returns true
+        fenixFxaManager = FenixAccountManager(context)
+
+        val result = fenixFxaManager.accountState
+
+        assertSame(AccountState.NEEDS_REAUTHENTICATION, result)
+    }
+
+    @Test
+    fun `GIVEN an account exists and doesn't need to be re-authenticated WHEN accountState is called THEN it returns AccountState#AUTHENTICATED`() {
+        every { context.components.backgroundServices.accountManager } returns accountManagerComponent
+        every { accountManagerComponent.authenticatedAccount() } returns mockk()
+        every { accountManagerComponent.accountNeedsReauth() } returns false
+        fenixFxaManager = FenixAccountManager(context)
+
+        val result = fenixFxaManager.accountState
+
+        assertSame(AccountState.AUTHENTICATED, result)
+    }
 }