Kallo SDK documentation

import 'package:kallo_sdk/kallo_sdk.dart';

Future<void> demo() async {
  // 1. Initialize — validates your license, then configures the SIP stack.
  await KalloClient.instance.init(
    KalloConfig(
      domain: 'sip.example.com',
      username: '1001',
      password: 'secret',
      licenseKey: 'YOUR-LICENSE-KEY',
      // licenseServerUrl defaults to https://kallo-api.up.railway.app
    ),
  );

  // 2. Listen for registration state changes.
  KalloClient.instance.registrationStream.listen((state) {
    print('registration: $state');
  });

  // 3. Register, then wait until we are registered.
  await KalloClient.instance.register();
  await KalloClient.instance.registrationStream
      .firstWhere((s) => s == KalloRegistrationState.registered);

  // 4. Place an outbound call and follow its state.
  final call = await KalloClient.instance.calls.makeCall('1002');
  call.stateStream.listen((state) {
    print('call: $state');
  });

  // 5. Hang up later.
  await call.hangup();
}

// Subscribing eagerly attaches the native listener, so inbound
// calls are not dropped before you handle them.
KalloClient.instance.calls.incomingCalls.listen((call) async {
  await call.accept(); // or: await call.reject();
});

try {
  await KalloClient.instance.init(config);
} on KalloLicenseException catch (e) {
  print('license problem: ${e.message}');
} on KalloException catch (e) {
  print('SDK error: ${e.message}');
}

Integrate the Kallo SDK (native SIP voice calling) into my Flutter app (Android & iOS).

About the SDK:
- Android (minSdk 28 / Android 9) and iOS (13+). One Flutter plugin package
  contains both platforms — Flutter builds the right half per target.
- Flutter 3.10+ / Dart 3.0+.
- Distributed as a closed-binary Flutter plugin package (the kallo_sdk Dart API
  plus prebuilt native binaries: an Android .aar and an iOS xcframework), NOT on
  pub.dev. Add it as a path: (or private git) dependency on the kallo_sdk package
  in pubspec.yaml — do not try to fetch it from pub.dev, and do not add the raw
  .aar/xcframework to the native projects directly.
- Android: requires the RECORD_AUDIO permission (plus INTERNET and
  MODIFY_AUDIO_SETTINGS) in AndroidManifest.xml, and the RECORD_AUDIO runtime
  permission must be requested and granted before placing or accepting a call.
- iOS: add NSMicrophoneUsageDescription to Info.plist. The SDK requests the mic
  at call time — do NOT pre-request microphone permission in the app (a host-app
  pre-request can block the call). Run pod install after flutter pub get.

Use the instance-based API (KalloClient.instance — NOT a static/global API):

  import 'package:kallo_sdk/kallo_sdk.dart';

  // 1. Initialize — validates the license, then configures the SIP stack.
  await KalloClient.instance.init(
    KalloConfig(
      domain: '<SIP domain>',
      username: '<SIP username>',
      password: '<SIP password>',
      licenseKey: '<Kallo license key>',
    ),
  );

  // 2. Listen to registration state.
  KalloClient.instance.registrationStream.listen((state) {
    // state is a KalloRegistrationState:
    // none | registering | registered | failed | expired
  });

  // 3. Register and wait until registered.
  await KalloClient.instance.register();
  await KalloClient.instance.registrationStream
      .firstWhere((s) => s == KalloRegistrationState.registered);

  // 4. Place an outbound call and follow its state.
  final call = await KalloClient.instance.calls.makeCall('<destination>');
  call.stateStream.listen((state) {
    // state is a KalloCallState:
    // idle | calling | ringing | active | held | ended | failed
  });

  // 5. Hang up.
  await call.hangup();

Build a minimal call screen (single StatefulWidget is fine) that:
- Calls init(...) then register() on start, and shows the current registration
  state in the UI.
- Has a text field for the destination extension/number and a "Call" button
  that invokes KalloClient.instance.calls.makeCall(<destination>).
- Shows the live call state from the returned call's stateStream.
- Has a "Hang up" button that calls call.hangup().
- Wraps init / register / makeCall in try/catch with error handling on the
  Kallo exception types: catch KalloLicenseException (bad/expired license),
  KalloRegistrationException (registration failed), KalloCallException (call
  failed), and KalloNetworkException, falling back to the KalloException base
  type. Show a readable message from e.message.

Important:
- Do NOT hardcode credentials. Ask me for my SIP domain, username, password,
  and Kallo license key, and wire them in from config / secure storage.
- Do NOT invent SDK methods. The full API reference (KalloConfig fields,
  KalloClient / KalloCall / KalloCallManager members, enums, exceptions) and
  install steps are on this same docs page — read it for anything not shown
  above, and ask me if a signature is unclear rather than guessing.