Add phone auth settings

FirebaseAuth/Tests/SampleSwift/AuthenticationExample/ViewControllers/SettingsViewController.swift

@@ -187,21 +187,89 @@ extension AuthSettings: DataSourceProvidable {
     return Section(headerDescription: "Keychain Access Groups", items: items)
   }
 
+  func truncatedString(string: String, length: Int) -> String {
+    guard string.count > length else { return string }
+
+    let half = (length - 3) / 2
+    let startIndex = string.startIndex
+    let midIndex = string.index(startIndex, offsetBy: half) // Ensure correct mid index
+    let endIndex = string.index(startIndex, offsetBy: string.count - half)
+
+    return "\(string[startIndex ..< midIndex])...\(string[endIndex...])"
+  }
+
+  func showPromptWithTitle(_ title: String, message: String, showCancelButton: Bool,
+                           completion: @escaping (Bool, String?) -> Void) {
+    let alertController = UIAlertController(title: title, message: message, preferredStyle: .alert)
+
+    alertController.addAction(UIAlertAction(title: "OK", style: .default, handler: { _ in
+      let userInput = alertController.textFields?.first?.text
+      completion(true, userInput)
+    }))
+
+    if showCancelButton {
+      alertController.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: { _ in
+        completion(false, nil)
+      }))
+    }
+
+    alertController.addTextField(configurationHandler: nil)
+  }
+
   // TODO: Add ability to click and clear both of these fields.
   private var phoneAuthSection: Section {
-    var tokenString = "No Token"
-    var credentialString = "No Credential"
-    if let token = AppManager.shared.auth().tokenManager.token {
-      let tokenType = token.type == .prod ? "Production" : "Sandbox"
-      tokenString = "token: \(token.string): type: \(tokenType)"
+    let items = [Item(title: APNSTokenString(), detailTitle: "APNs Token"),
+                 Item(title: appCredentialString(), detailTitle: "App Credential")]
+    return Section(headerDescription: "Phone Auth - TODO toggle off", items: items)
+  }
+
+  func APNSTokenString() -> String {
+    guard let token = AppManager.shared.auth().tokenManager.token else {
+      return "No APNs token"
+    }
+
+    let truncatedToken = truncatedString(string: token.string, length: 19)
+    let tokenType = token.type == .prod ? "P" : "S"
+    return "\(truncatedToken)(\(tokenType))"
+  }
+
+  func clearAPNSToken() {
+    guard let token = AppManager.shared.auth().tokenManager.token else {
+      return
+    }
+
+    let tokenType = token.type == .prod ? "Production" : "Sandbox"
+    let message = "token: \(token.string)\ntype: \(tokenType)"
+
+    showPromptWithTitle("Clear APNs Token?", message: message,
+                        showCancelButton: true) { userPressedOK, userInput in
+      if userPressedOK {
+        AppManager.shared.auth().tokenManager.token = nil
+      }
+    }
+  }
+
+  func appCredentialString() -> String {
+    if let credential = AppManager.shared.auth().appCredentialManager.credential {
+      let truncatedReceipt = truncatedString(string: credential.receipt, length: 13)
+      let truncatedSecret = truncatedString(string: credential.secret ?? "", length: 13)
+      return "\(truncatedReceipt)/\(truncatedSecret)"
+    } else {
+      return "No App Credential"
     }
+  }
+
+  func clearAppCredential() {
     if let credential = AppManager.shared.auth().appCredentialManager.credential {
-      // TODO: Maybe use truncatedString like ObjC sample
-      credentialString = "\(credential.receipt)/\(credential.secret ?? "nil")"
+      let message = "receipt: \(credential.receipt)\nsecret: \(credential.secret)"
+
+      showPromptWithTitle("Clear App Credential?", message: message,
+                          showCancelButton: true) { userPressedOK, _ in
+        if userPressedOK {
+          AppManager.shared.auth().appCredentialManager.clearCredential()
+        }
+      }
     }
-    let items = [Item(title: tokenString, detailTitle: "APNs Token"),
-                 Item(title: credentialString, detailTitle: "App Credential")]
-    return Section(headerDescription: "Phone Auth - TODO toggle off", items: items)
   }
 
   private var languageSection: Section {