TF-825 Download email as EML file (#2854)

lib/features/email/data/network/email_api.dart

@@ -351,12 +351,12 @@ class EmailAPI with HandleSetErrorMixin {
             headers: headerParam,
             responseType: ResponseType.bytes),
         onReceiveProgress: (downloaded, total) {
-          log('DownloadClient::downloadFileForWeb(): downloaded = $downloaded | total: $total');
+          log('EmailAPI::downloadFileForWeb(): downloaded = $downloaded | total: $total');
           double progress = 0;
-          if (downloaded > 0 && total > downloaded) {
+          if (downloaded > 0 && total >= downloaded) {
             progress = (downloaded / total) * 100;
           }
-          log('DownloadClient::downloadFileForWeb(): progress = ${progress.round()}%');
+          log('EmailAPI::downloadFileForWeb(): progress = ${progress.round()}%');
           onReceiveController.add(Right(DownloadingAttachmentForWeb(
               taskId,
               attachment,

lib/features/email/domain/exceptions/email_exceptions.dart

@@ -4,4 +4,6 @@ class NotFoundEmailContentException implements Exception {}
 
 class EmptyEmailContentException implements Exception {}
 
-class NotFoundEmailRecoveryActionException implements Exception {}
+class NotFoundEmailRecoveryActionException implements Exception {}
+
+class NotFoundEmailBlobIdException implements Exception {}

lib/features/email/domain/state/download_attachment_for_web_state.dart

@@ -1,7 +1,6 @@
 import 'dart:typed_data';
 import 'package:core/presentation/state/failure.dart';
 import 'package:core/presentation/state/success.dart';
-import 'package:jmap_dart_client/jmap/core/id.dart';
 import 'package:model/download/download_task_id.dart';
 import 'package:model/email/attachment.dart';
 
@@ -59,14 +58,14 @@ class DownloadAttachmentForWebSuccess extends UIState {
 class DownloadAttachmentForWebFailure extends FeatureFailure {
 
   final DownloadTaskId? taskId;
-  final Id? attachmentBlobId;
+  final Attachment? attachment;
 
   DownloadAttachmentForWebFailure({
-    required this.attachmentBlobId,
+    this.attachment,
     this.taskId,
     dynamic exception
   }) : super(exception: exception);
 
   @override
-  List<Object?> get props => [taskId, ...super.props];
+  List<Object?> get props => [attachment, taskId, ...super.props];
 }

lib/features/email/domain/state/view_attachment_for_web_state.dart

@@ -22,7 +22,7 @@ class ViewAttachmentForWebSuccess extends DownloadAttachmentForWebSuccess {
 
 class ViewAttachmentForWebFailure extends DownloadAttachmentForWebFailure {
   ViewAttachmentForWebFailure({
-    required super.attachmentBlobId,
+    required super.attachment,
     super.taskId,
     super.exception,
   });

lib/features/email/domain/usecases/download_attachment_for_web_interactor.dart

@@ -72,7 +72,7 @@ class DownloadAttachmentForWebInteractor {
     } catch (exception) {
       yield Left<Failure, Success>(
         DownloadAttachmentForWebFailure(
-          attachmentBlobId: attachment.blobId,
+          attachment: attachment,
           taskId: taskId,
           exception: exception
         )

lib/features/email/domain/usecases/view_attachment_for_web_interactor.dart

@@ -34,7 +34,7 @@ class ViewAttachmentForWebInteractor {
               (failure) {
                 if (failure is DownloadAttachmentForWebFailure) {
                   return Left(ViewAttachmentForWebFailure(
-                    attachmentBlobId: attachment.blobId,
+                    attachment: attachment,
                     taskId: failure.taskId,
                     exception: failure.exception,
                   ));

lib/features/email/presentation/controller/single_email_controller.dart

@@ -20,6 +20,7 @@ import 'package:jmap_dart_client/jmap/mail/email/email_address.dart';
 import 'package:jmap_dart_client/jmap/mdn/disposition.dart';
 import 'package:jmap_dart_client/jmap/mdn/mdn.dart';
 import 'package:mime/mime.dart';
+import 'package:model/email/eml_attachment.dart';
 import 'package:model/model.dart';
 import 'package:permission_handler/permission_handler.dart';
 import 'package:pointer_interceptor/pointer_interceptor.dart';
@@ -28,6 +29,7 @@ import 'package:tmail_ui_user/features/base/base_controller.dart';
 import 'package:tmail_ui_user/features/base/mixin/app_loader_mixin.dart';
 import 'package:tmail_ui_user/features/composer/presentation/extensions/email_action_type_extension.dart';
 import 'package:tmail_ui_user/features/destination_picker/presentation/model/destination_picker_arguments.dart';
+import 'package:tmail_ui_user/features/email/domain/exceptions/email_exceptions.dart';
 import 'package:tmail_ui_user/features/email/domain/extensions/list_attachments_extension.dart';
 import 'package:tmail_ui_user/features/email/domain/model/detailed_email.dart';
 import 'package:tmail_ui_user/features/email/domain/model/email_print.dart';
@@ -810,7 +812,7 @@ class SingleEmailController extends BaseController with AppLoaderMixin {
     } else {
       consumeState(Stream.value(
         Left(DownloadAttachmentForWebFailure(
-          attachmentBlobId: attachment.blobId,
+          attachment: attachment,
           exception: NotFoundSessionException()))
       ));
     }
@@ -831,7 +833,7 @@ class SingleEmailController extends BaseController with AppLoaderMixin {
     } else {
       consumeState(Stream.value(
         Left(ViewAttachmentForWebFailure(
-          attachmentBlobId: attachment.blobId,
+          attachment: attachment,
           exception: NotFoundSessionException()))
       ));
     }
@@ -876,12 +878,16 @@ class SingleEmailController extends BaseController with AppLoaderMixin {
       mailboxDashBoardController.deleteDownloadTask(failure.taskId!);
     }
 
-    _updateAttachmentsViewState(failure.attachmentBlobId, Left(failure));
+    if (failure.attachment != null) {
+      _updateAttachmentsViewState(failure.attachment?.blobId, Left(failure));
+    }
 
     if (currentOverlayContext != null && currentContext != null) {
       appToast.showToastErrorMessage(
         currentOverlayContext!,
-        AppLocalizations.of(currentContext!).attachment_download_failed);
+        failure.attachment is EMLAttachment
+          ? AppLocalizations.of(currentContext!).downloadMessageAsEMLFailed
+          : AppLocalizations.of(currentContext!).attachment_download_failed);
     }
   }
 
@@ -1141,6 +1147,9 @@ class SingleEmailController extends BaseController with AppLoaderMixin {
       case EmailActionType.printAll:
         _printEmail(context, presentationEmail);
         break;
+      case EmailActionType.downloadMessageAsEML:
+        _downloadMessageAsEML(presentationEmail);
+        break;
       default:
         break;
     }
@@ -1772,4 +1781,14 @@ class SingleEmailController extends BaseController with AppLoaderMixin {
         AppLocalizations.of(currentContext!).eventReplyWasSentUnsuccessfully);
     }
   }
+
+  void _downloadMessageAsEML(PresentationEmail presentationEmail) {
+    final emlAttachment = presentationEmail.createEMLAttachment();
+    if (emlAttachment.blobId == null) {
+      consumeState(Stream.value(Left(DownloadAttachmentForWebFailure(exception: NotFoundEmailBlobIdException()))));
+      return;
+    }
+
+    downloadAttachmentForWeb(emlAttachment);
+  }
 }

lib/features/email/presentation/email_view.dart

@@ -473,6 +473,8 @@ class EmailView extends GetWidget<SingleEmailController> {
         EmailActionType.unsubscribe,
       if (mailboxContain?.isArchive == false)
         EmailActionType.archiveMessage,
+      if (PlatformInfo.isWeb && PlatformInfo.isCanvasKit)
+        EmailActionType.downloadMessageAsEML
     ];
 
     if (position == null) {

lib/features/email/presentation/utils/email_utils.dart

@@ -1,6 +1,5 @@
 
 import 'package:collection/collection.dart';
-import 'package:core/utils/app_logger.dart';
 import 'package:get/get_utils/src/get_utils/get_utils.dart';
 import 'package:core/core.dart';
 import 'package:dartz/dartz.dart';