feat: Phone Provider Integration (#2240)

Author: demolaf

auth/src/main/java/com/firebase/ui/auth/compose/AuthState.kt

@@ -20,6 +20,8 @@ import com.google.firebase.auth.AuthCredential
 import com.google.firebase.auth.AuthResult
 import com.google.firebase.auth.FirebaseUser
 import com.google.firebase.auth.MultiFactorResolver
+import com.google.firebase.auth.PhoneAuthCredential
+import com.google.firebase.auth.PhoneAuthProvider
 
 /**
  * Represents the authentication state in Firebase Auth UI.
@@ -252,6 +254,74 @@ abstract class AuthState private constructor() {
         override fun toString(): String = "AuthState.EmailSignInLinkSent"
     }
 
+    /**
+     * Phone number was automatically verified via SMS instant verification.
+     *
+     * This state is emitted when Firebase Phone Authentication successfully retrieves
+     * and verifies the SMS code automatically without user interaction. This happens
+     * when Google Play services can detect the incoming SMS message.
+     *
+     * @property credential The [PhoneAuthCredential] that can be used to sign in the user
+     *
+     * @see PhoneNumberVerificationRequired for the manual verification flow
+     */
+    class SMSAutoVerified(val credential: PhoneAuthCredential) : AuthState() {
+        override fun equals(other: Any?): Boolean {
+            if (this === other) return true
+            if (other !is SMSAutoVerified) return false
+            return credential == other.credential
+        }
+
+        override fun hashCode(): Int {
+            var result = credential.hashCode()
+            result = 31 * result + credential.hashCode()
+            return result
+        }
+
+        override fun toString(): String =
+            "AuthState.SMSAutoVerified(credential=$credential)"
+    }
+
+    /**
+     * Phone number verification requires manual code entry.
+     *
+     * This state is emitted when Firebase Phone Authentication cannot instantly verify
+     * the phone number and sends an SMS code that the user must manually enter. This is
+     * the normal flow when automatic SMS retrieval is not available or fails.
+     *
+     * **Resending codes:**
+     * To allow users to resend the verification code (if they didn't receive it),
+     * call [FirebaseAuthUI.verifyPhoneNumber] again with:
+     * - `isForceResendingTokenEnabled = true`
+     * - `forceResendingToken` from this state
+     *
+     * @property verificationId The verification ID to use when submitting the code.
+     *                          This must be passed to [FirebaseAuthUI.submitVerificationCode].
+     * @property forceResendingToken Token that can be used to resend the SMS code if needed
+     *
+     */
+    class PhoneNumberVerificationRequired(
+        val verificationId: String,
+        val forceResendingToken: PhoneAuthProvider.ForceResendingToken,
+    ) : AuthState() {
+        override fun equals(other: Any?): Boolean {
+            if (this === other) return true
+            if (other !is PhoneNumberVerificationRequired) return false
+            return verificationId == other.verificationId &&
+                    forceResendingToken == other.forceResendingToken
+        }
+
+        override fun hashCode(): Int {
+            var result = verificationId.hashCode()
+            result = 31 * result + forceResendingToken.hashCode()
+            return result
+        }
+
+        override fun toString(): String =
+            "AuthState.PhoneNumberVerificationRequired(verificationId=$verificationId, " +
+                    "forceResendingToken=$forceResendingToken)"
+    }
+
     companion object {
         /**
          * Creates an Idle state instance.