replace string enum usage with dart enums

example/lib/src/callscreen.dart

@@ -34,7 +34,7 @@ class _MyCallScreenWidget extends State<CallScreenWidget>
   bool _speakerOn = false;
   bool _hold = false;
   bool _mirror = true;
-  String? _holdOriginator;
+  Originator? _holdOriginator;
   bool _callConfirmed = false;
   CallStateEnum _state = CallStateEnum.NONE;
 
@@ -47,7 +47,7 @@ class _MyCallScreenWidget extends State<CallScreenWidget>
 
   String? get remoteIdentity => call!.remote_identity;
 
-  String get direction => call!.direction;
+  Direction? get direction => call!.direction;
 
   Call? get call => widget._call;
 
@@ -177,7 +177,7 @@ class _MyCallScreenWidget extends State<CallScreenWidget>
 
   void _handleStreams(CallState event) async {
     MediaStream? stream = event.stream;
-    if (event.originator == 'local') {
+    if (event.originator == Originator.local) {
       if (_localRenderer != null) {
         _localRenderer!.srcObject = stream;
       }
@@ -189,7 +189,7 @@ class _MyCallScreenWidget extends State<CallScreenWidget>
       }
       _localStream = stream;
     }
-    if (event.originator == 'remote') {
+    if (event.originator == Originator.remote) {
       if (_remoteRenderer != null) {
         _remoteRenderer!.srcObject = stream;
       }
@@ -423,7 +423,7 @@ class _MyCallScreenWidget extends State<CallScreenWidget>
     switch (_state) {
       case CallStateEnum.NONE:
       case CallStateEnum.CONNECTING:
-        if (direction == 'INCOMING') {
+        if (direction == Direction.incoming) {
           basicActions.add(ActionButton(
             title: "Accept",
             fillColor: Colors.green,
@@ -608,7 +608,7 @@ class _MyCallScreenWidget extends State<CallScreenWidget>
                       child: Text(
                         (voiceOnly ? 'VOICE CALL' : 'VIDEO CALL') +
                             (_hold
-                                ? ' PAUSED BY ${_holdOriginator!.toUpperCase()}'
+                                ? ' PAUSED BY ${_holdOriginator!.name}'
                                 : ''),
                         style: TextStyle(fontSize: 24, color: textColor),
                       ),

example/pubspec.yaml

@@ -15,7 +15,7 @@ version: 1.0.0+1
 publish_to: none
 
 environment:
-  sdk: ">=2.12.0 <3.0.0"
+  sdk: ">=2.15.0 <3.0.0"
   flutter: ">=1.10.0"
 
 dependencies:

lib/sip_ua.dart

@@ -1,4 +1,5 @@
 export 'src/enum_helper.dart';
+export 'src/enums.dart';
 export 'src/sip_message.dart';
 export 'src/sip_ua_helper.dart';
 export 'src/transport_type.dart';

lib/src/config.dart

@@ -1,11 +1,10 @@
-import 'package:sip_ua/sip_ua.dart';
-import 'package:sip_ua/src/transports/socket_interface.dart';
-import 'package:sip_ua/src/transports/tcp_socket.dart';
+import '../sip_ua.dart';
 import 'constants.dart' as DartSIP_C;
 import 'constants.dart';
 import 'exceptions.dart' as Exceptions;
 import 'grammar.dart';
 import 'logger.dart';
+import 'transports/socket_interface.dart';
 import 'transports/web_socket.dart';
 import 'utils.dart' as Utils;
 

lib/src/enums.dart

@@ -0,0 +1,39 @@
+/// Defines the direction of a communication,
+/// indicating whether it is outgoing or incoming.
+///
+/// Used to specify the flow of calls or messages.
+enum Direction {
+  /// Represents an outgoing call or message.
+  outgoing,
+
+  /// Represents an incoming call or message.
+  incoming
+}
+
+/// Identifies the originator of a communication,
+/// specifying whether the initiator is local or remote.
+///
+/// This is useful for determining who started the call or message.
+enum Originator {
+  /// Represents the user of this device initiated the communication.
+  local,
+
+  /// Represents the communication was initiated by someone else.
+  remote,
+
+  /// Represents that the communication was initiated by the system (e.g., automated processes).
+  system,
+}
+
+/// Represents the type of SDP (Session Description Protocol) message
+/// used in a communication session.
+///
+/// SDP messages are exchanged between peers during the setup of a media connection.
+enum SdpType {
+  /// Represents an SDP offer, which is the initial proposal sent to set up a media session.
+  offer,
+
+  /// Represents an SDP answer, which is the response to an SDP offer,
+  /// confirming or adjusting the session parameters.
+  answer
+}

lib/src/event_manager/call_events.dart

@@ -1,5 +1,6 @@
 import 'package:flutter_webrtc/flutter_webrtc.dart';
 
+import '../enums.dart';
 import '../rtc_session.dart';
 import '../sip_message.dart';
 import 'events.dart';
@@ -11,9 +12,10 @@ class CallEvent extends EventType {
 }
 
 class EventNewRTCSession extends CallEvent {
-  EventNewRTCSession({RTCSession? session, String? originator, dynamic request})
+  EventNewRTCSession(
+      {RTCSession? session, Originator? originator, dynamic request})
       : super(session);
-  String? originator;
+  Originator? originator;
   dynamic request;
 }
 
@@ -25,7 +27,7 @@ class EventCallEnded extends CallEvent {
   EventCallEnded(
       {RTCSession? session, this.originator, this.cause, this.request})
       : super(session);
-  String? originator;
+  Originator? originator;
   ErrorCause? cause;
   IncomingRequest? request;
 }
@@ -34,26 +36,27 @@ class EventCallProgress extends CallEvent {
   EventCallProgress(
       {RTCSession? session, this.originator, this.response, this.cause})
       : super(session);
-  String? originator;
+  Originator? originator;
   dynamic response;
   ErrorCause? cause;
 }
 
 class EventCallConfirmed extends CallEvent {
   EventCallConfirmed({RTCSession? session, this.originator, this.ack})
       : super(session);
-  String? originator;
+  Originator? originator;
   dynamic ack;
 }
 
 class EventCallHold extends CallEvent {
   EventCallHold({RTCSession? session, this.originator}) : super(session);
-  String? originator;
+  Originator? originator;
 }
 
 class EventCallUnhold extends CallEvent {
-  EventCallUnhold({RTCSession? session, String? originator}) : super(session);
-  String? originator;
+  EventCallUnhold({RTCSession? session, Originator? originator})
+      : super(session);
+  Originator? originator;
 }
 
 class EventCallMuted extends CallEvent {
@@ -73,7 +76,7 @@ class EventCallUnmuted extends CallEvent {
 class EventCallAccepted extends CallEvent {
   EventCallAccepted({RTCSession? session, this.originator, this.response})
       : super(session);
-  String? originator;
+  Originator? originator;
   dynamic response;
 }
 
@@ -89,7 +92,7 @@ class EventCallFailed extends CallEvent {
       this.status_line})
       : super(session);
   dynamic response;
-  String? originator;
+  Originator? originator;
   ErrorCause? cause;
   dynamic request;
   String? status_line;
@@ -98,7 +101,7 @@ class EventCallFailed extends CallEvent {
 class EventStream extends CallEvent {
   EventStream({RTCSession? session, this.originator, this.stream})
       : super(session);
-  String? originator;
+  Originator? originator;
   MediaStream? stream;
 }
 

lib/src/event_manager/internal_events.dart

@@ -1,5 +1,6 @@
 import 'package:flutter_webrtc/flutter_webrtc.dart';
 
+import '../enums.dart';
 import '../rtc_session.dart' show RTCSession;
 import '../rtc_session/dtmf.dart';
 import '../rtc_session/info.dart';
@@ -33,8 +34,8 @@ class EventOnAuthenticated extends EventType {
 
 class EventSdp extends EventType {
   EventSdp({this.originator, this.type, this.sdp});
-  String? originator;
-  String? type;
+  Originator? originator;
+  SdpType? type;
   String? sdp;
 }
 
@@ -55,7 +56,7 @@ class EventSetLocalDescriptionFailed extends EventType {
 
 class EventFailedUnderScore extends EventType {
   EventFailedUnderScore({this.originator, this.cause});
-  String? originator;
+  Originator? originator;
   ErrorCause? cause;
 }
 
@@ -66,14 +67,14 @@ class EventGetUserMediaFailed extends EventType {
 
 class EventNewDTMF extends EventType {
   EventNewDTMF({this.originator, this.request, this.dtmf});
-  String? originator;
+  Originator? originator;
   dynamic request;
   DTMF? dtmf;
 }
 
 class EventNewInfo extends EventType {
   EventNewInfo({this.originator, this.request, this.info});
-  String? originator;
+  Originator? originator;
   dynamic request;
   Info? info;
 }
@@ -127,7 +128,7 @@ class EventOnFialed extends EventType {}
 
 class EventSucceeded extends EventType {
   EventSucceeded({this.response, this.originator});
-  String? originator;
+  Originator? originator;
   IncomingMessage? response;
 }
 

lib/src/event_manager/message_events.dart

@@ -1,9 +1,10 @@
+import '../enums.dart';
 import '../message.dart';
 import 'events.dart';
 
 class EventNewMessage extends EventType {
   EventNewMessage({this.message, this.originator, this.request});
   dynamic request;
-  String? originator;
+  Originator? originator;
   Message? message;
 }

lib/src/event_manager/notifier_events.dart

@@ -1,4 +1,4 @@
-import 'package:sip_ua/src/sip_message.dart';
+import '../sip_message.dart';
 import 'events.dart';
 
 class EventTerminated extends EventType {

lib/src/event_manager/options_events.dart

@@ -1,9 +1,10 @@
+import '../enums.dart';
 import '../options.dart';
 import 'events.dart';
 
 class EventNewOptions extends EventType {
   EventNewOptions({this.message, this.originator, this.request});
   dynamic request;
-  String? originator;
+  Originator? originator;
   Options? message;
 }

lib/src/event_manager/transport_events.dart

@@ -1,4 +1,4 @@
-import 'package:sip_ua/src/transports/socket_interface.dart';
+import '../transports/socket_interface.dart';
 import '../transports/web_socket.dart';
 import 'events.dart';