Export collection with different provider

app/lib/entity/collection/exporter.dart

@@ -0,0 +1,108 @@
+import 'package:clock/clock.dart';
+import 'package:collection/collection.dart';
+import 'package:kiwi/kiwi.dart';
+import 'package:logging/logging.dart';
+import 'package:nc_photos/account.dart';
+import 'package:nc_photos/controller/collections_controller.dart';
+import 'package:nc_photos/di_container.dart';
+import 'package:nc_photos/entity/album.dart';
+import 'package:nc_photos/entity/album/cover_provider.dart';
+import 'package:nc_photos/entity/album/item.dart';
+import 'package:nc_photos/entity/album/provider.dart';
+import 'package:nc_photos/entity/album/sort_provider.dart';
+import 'package:nc_photos/entity/collection.dart';
+import 'package:nc_photos/entity/collection/content_provider/album.dart';
+import 'package:nc_photos/entity/collection/content_provider/nc_album.dart';
+import 'package:nc_photos/entity/collection_item.dart';
+import 'package:nc_photos/entity/file_descriptor.dart';
+import 'package:nc_photos/entity/nc_album.dart';
+import 'package:nc_photos/use_case/find_file.dart';
+import 'package:np_codegen/np_codegen.dart';
+
+part 'exporter.g.dart';
+
+@npLog
+class CollectionExporter {
+  const CollectionExporter(this.account, this.collectionsController,
+      this.collection, this.items, this.exportName);
+
+  /// Export as a new collection backed by our client side album
+  Future<Collection> asAlbum() async {
+    final files = await FindFile(KiwiContainer().resolve<DiContainer>())(
+      account,
+      items.whereType<CollectionFileItem>().map((e) => e.file.fdId).toList(),
+      onFileNotFound: (fileId) {
+        _log.severe("[asAlbum] File not found: $fileId");
+      },
+    );
+    final newAlbum = Album(
+      name: exportName,
+      provider: AlbumStaticProvider(
+        items: items
+            .map((e) {
+              if (e is CollectionFileItem) {
+                final f = files
+                    .firstWhereOrNull((f) => f.compareServerIdentity(e.file));
+                if (f == null) {
+                  return null;
+                } else {
+                  return AlbumFileItem(
+                    addedBy: account.userId,
+                    addedAt: clock.now().toUtc(),
+                    file: f,
+                  );
+                }
+              } else if (e is CollectionLabelItem) {
+                return AlbumLabelItem(
+                  addedBy: account.userId,
+                  addedAt: clock.now().toUtc(),
+                  text: e.text,
+                );
+              } else {
+                return null;
+              }
+            })
+            .whereNotNull()
+            .toList(),
+        latestItemTime: collection.lastModified,
+      ),
+      coverProvider: const AlbumAutoCoverProvider(),
+      sortProvider: const AlbumTimeSortProvider(isAscending: false),
+    );
+    var newCollection = Collection(
+      name: exportName,
+      contentProvider: CollectionAlbumProvider(
+        account: account,
+        album: newAlbum,
+      ),
+    );
+    return await collectionsController.createNew(newCollection);
+  }
+
+  /// Export as a new collection backed by Nextcloud album
+  Future<Collection> asNcAlbum() async {
+    var newCollection = Collection(
+      name: exportName,
+      contentProvider: CollectionNcAlbumProvider(
+        account: account,
+        album: NcAlbum.createNew(account: account, name: exportName),
+      ),
+    );
+    newCollection = await collectionsController.createNew(newCollection);
+    // only files are supported in NcAlbum
+    final newFiles =
+        items.whereType<CollectionFileItem>().map((e) => e.file).toList();
+    final data = collectionsController
+        .peekStream()
+        .data
+        .firstWhere((e) => e.collection.compareIdentity(newCollection));
+    await data.controller.addFiles(newFiles);
+    return newCollection;
+  }
+
+  final Account account;
+  final CollectionsController collectionsController;
+  final Collection collection;
+  final List<CollectionItem> items;
+  final String exportName;
+}

app/lib/entity/collection/exporter.g.dart

@@ -0,0 +1,14 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'exporter.dart';
+
+// **************************************************************************
+// NpLogGenerator
+// **************************************************************************
+
+extension _$CollectionExporterNpLog on CollectionExporter {
+  // ignore: unused_element
+  Logger get _log => log;
+
+  static final log = Logger("entity.collection.exporter.CollectionExporter");
+}

app/lib/widget/collection_browser.dart

@@ -43,6 +43,7 @@ import 'package:nc_photos/use_case/inflate_file_descriptor.dart';
 import 'package:nc_photos/use_case/remove.dart';
 import 'package:nc_photos/widget/collection_picker.dart';
 import 'package:nc_photos/widget/draggable_item_list.dart';
+import 'package:nc_photos/widget/export_collection_dialog.dart';
 import 'package:nc_photos/widget/fancy_option_picker.dart';
 import 'package:nc_photos/widget/file_sharer.dart';
 import 'package:nc_photos/widget/network_thumbnail.dart';

app/lib/widget/collection_browser.g.dart

@@ -160,6 +160,13 @@ extension _$_DownloadToString on _Download {
   }
 }
 
+extension _$_ExportToString on _Export {
+  String _$toString() {
+    // ignore: unnecessary_string_interpolations
+    return "_Export {}";
+  }
+}
+
 extension _$_BeginEditToString on _BeginEdit {
   String _$toString() {
     // ignore: unnecessary_string_interpolations

app/lib/widget/collection_browser/app_bar.dart

@@ -41,11 +41,16 @@ class _AppBar extends StatelessWidget {
                   value: _MenuOption.unsetCover,
                   child: Text(L10n.global().unsetAlbumCoverTooltip),
                 ),
-              if (state.items.isNotEmpty)
+              if (state.items.isNotEmpty) ...[
                 PopupMenuItem(
                   value: _MenuOption.download,
                   child: Text(L10n.global().downloadTooltip),
                 ),
+                const PopupMenuItem(
+                  value: _MenuOption.export,
+                  child: Text("Export"),
+                ),
+              ],
             ],
             onSelected: (option) {
               _onMenuSelected(context, option);
@@ -82,6 +87,24 @@ class _AppBar extends StatelessWidget {
       case _MenuOption.download:
         context.read<_Bloc>().add(const _Download());
         break;
+      case _MenuOption.export:
+        _onExportSelected(context);
+        break;
+    }
+  }
+
+  Future<void> _onExportSelected(BuildContext context) async {
+    final bloc = context.read<_Bloc>();
+    final result = await showDialog<Collection>(
+      context: context,
+      builder: (_) => ExportCollectionDialog(
+        account: bloc.account,
+        collection: bloc.state.collection,
+        items: bloc.state.items,
+      ),
+    );
+    if (result != null) {
+      Navigator.of(context).pop();
     }
   }
 }
@@ -374,6 +397,7 @@ enum _MenuOption {
   edit,
   unsetCover,
   download,
+  export,
 }
 
 enum _SelectionMenuOption {

app/lib/widget/collection_browser/state_event.dart

@@ -112,6 +112,14 @@ class _Download implements _Event {
   String toString() => _$toString();
 }
 
+@toString
+class _Export implements _Event {
+  const _Export();
+
+  @override
+  String toString() => _$toString();
+}
+
 @toString
 class _BeginEdit implements _Event {
   const _BeginEdit();

app/lib/widget/export_collection_dialog.dart

@@ -0,0 +1,225 @@
+import 'dart:async';
+
+import 'package:copy_with/copy_with.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:logging/logging.dart';
+import 'package:nc_photos/account.dart';
+import 'package:nc_photos/app_localizations.dart';
+import 'package:nc_photos/controller/account_controller.dart';
+import 'package:nc_photos/controller/collections_controller.dart';
+import 'package:nc_photos/entity/collection.dart';
+import 'package:nc_photos/entity/collection/exporter.dart';
+import 'package:nc_photos/entity/collection_item.dart';
+import 'package:nc_photos/exception_event.dart';
+import 'package:nc_photos/exception_util.dart' as exception_util;
+import 'package:nc_photos/k.dart' as k;
+import 'package:nc_photos/snack_bar_manager.dart';
+import 'package:nc_photos/widget/processing_dialog.dart';
+import 'package:np_codegen/np_codegen.dart';
+import 'package:to_string/to_string.dart';
+
+part 'export_collection_dialog.g.dart';
+part 'export_collection_dialog/bloc.dart';
+part 'export_collection_dialog/state_event.dart';
+
+class ExportCollectionDialog extends StatelessWidget {
+  const ExportCollectionDialog({
+    super.key,
+    required this.account,
+    required this.collection,
+    required this.items,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return BlocProvider(
+      create: (context) => _Bloc(
+        account: account,
+        collectionsController:
+            context.read<AccountController>().collectionsController,
+        collection: collection,
+        items: items,
+      ),
+      child: const _WrappedExportCollectionDialog(),
+    );
+  }
+
+  final Account account;
+  final Collection collection;
+  final List<CollectionItem> items;
+}
+
+class _WrappedExportCollectionDialog extends StatefulWidget {
+  const _WrappedExportCollectionDialog();
+
+  @override
+  State<StatefulWidget> createState() => _WrappedExportCollectionDialogState();
+}
+
+@npLog
+class _WrappedExportCollectionDialogState
+    extends State<_WrappedExportCollectionDialog> {
+  @override
+  Widget build(BuildContext context) {
+    return MultiBlocListener(
+      listeners: [
+        BlocListener<_Bloc, _State>(
+          listenWhen: (previous, current) =>
+              previous.result != current.result && current.result != null,
+          listener: _onResult,
+        ),
+        BlocListener<_Bloc, _State>(
+          listenWhen: (previous, current) => previous.error != current.error,
+          listener: (_, state) {
+            if (state.error != null) {
+              SnackBarManager().showSnackBar(SnackBar(
+                content: Text(exception_util.toUserString(state.error!.error)),
+                duration: k.snackBarDurationNormal,
+              ));
+            }
+          },
+        ),
+      ],
+      child: BlocBuilder<_Bloc, _State>(
+        buildWhen: (previous, current) =>
+            previous.isExporting != current.isExporting,
+        builder: (context, state) {
+          if (state.isExporting) {
+            return ProcessingDialog(
+              text: L10n.global().genericProcessingDialogContent,
+            );
+          } else {
+            return AlertDialog(
+              title: const Text("Export collection"),
+              content: Form(
+                key: _formKey,
+                child: Container(
+                  constraints: const BoxConstraints.tightFor(width: 280),
+                  child: Column(
+                    mainAxisSize: MainAxisSize.min,
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    children: const [
+                      _NameTextField(),
+                      _ProviderDropdown(),
+                      SizedBox(height: 8),
+                      _ProviderDescription(),
+                    ],
+                  ),
+                ),
+              ),
+              actions: [
+                TextButton(
+                  onPressed: () => _onOkPressed(context),
+                  child: Text(MaterialLocalizations.of(context).okButtonLabel),
+                ),
+              ],
+            );
+          }
+        },
+      ),
+    );
+  }
+
+  Future<void> _onOkPressed(BuildContext context) async {
+    if (_formKey.currentState?.validate() == true) {
+      _bloc.add(const _SubmitForm());
+    }
+  }
+
+  void _onResult(BuildContext context, _State state) {
+    Navigator.of(context).pop(state.result);
+  }
+
+  late final _bloc = context.read<_Bloc>();
+
+  final _formKey = GlobalKey<FormState>();
+}
+
+class _NameTextField extends StatelessWidget {
+  const _NameTextField();
+
+  @override
+  Widget build(BuildContext context) {
+    return TextFormField(
+      decoration: InputDecoration(
+        hintText: L10n.global().nameInputHint,
+      ),
+      initialValue: context.read<_Bloc>().state.formValue.name,
+      validator: (value) {
+        if (value!.isEmpty) {
+          return L10n.global().albumNameInputInvalidEmpty;
+        }
+        return null;
+      },
+      onChanged: (value) {
+        context.read<_Bloc>().add(_SubmitName(value));
+      },
+    );
+  }
+}
+
+class _ProviderDropdown extends StatelessWidget {
+  const _ProviderDropdown();
+
+  @override
+  Widget build(BuildContext context) {
+    return BlocBuilder<_Bloc, _State>(
+      buildWhen: (previous, current) =>
+          previous.formValue.provider != current.formValue.provider,
+      builder: (context, state) => DropdownButtonHideUnderline(
+        child: DropdownButtonFormField<_ProviderOption>(
+          value: state.formValue.provider,
+          items: _ProviderOption.values
+              .map((e) => DropdownMenuItem<_ProviderOption>(
+                    value: e,
+                    child: Text(e.toValueString(context)),
+                  ))
+              .toList(),
+          onChanged: (value) {
+            context.read<_Bloc>().add(_SubmitProvider(value!));
+          },
+        ),
+      ),
+    );
+  }
+}
+
+class _ProviderDescription extends StatelessWidget {
+  const _ProviderDescription();
+
+  @override
+  Widget build(BuildContext context) {
+    return BlocBuilder<_Bloc, _State>(
+      buildWhen: (previous, current) =>
+          previous.formValue.provider != current.formValue.provider,
+      builder: (context, state) => Text(
+        state.formValue.provider.toDescription(context),
+        style: Theme.of(context).textTheme.bodyText2,
+      ),
+    );
+  }
+}
+
+enum _ProviderOption {
+  appAlbum,
+  ncAlbum;
+
+  String toValueString(BuildContext context) {
+    switch (this) {
+      case appAlbum:
+        return L10n.global().createCollectionDialogAlbumLabel;
+      case ncAlbum:
+        return "Nextcloud Album";
+    }
+  }
+
+  String toDescription(BuildContext context) {
+    switch (this) {
+      case appAlbum:
+        return L10n.global().createCollectionDialogAlbumDescription;
+      case ncAlbum:
+        return "Server-side album, require Nextcloud 25 or above";
+    }
+  }
+}

app/lib/widget/export_collection_dialog.g.dart

@@ -0,0 +1,113 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'export_collection_dialog.dart';
+
+// **************************************************************************
+// CopyWithLintRuleGenerator
+// **************************************************************************
+
+// ignore_for_file: library_private_types_in_public_api, duplicate_ignore
+
+// **************************************************************************
+// CopyWithGenerator
+// **************************************************************************
+
+abstract class $_FormValueCopyWithWorker {
+  _FormValue call({String? name, _ProviderOption? provider});
+}
+
+class _$_FormValueCopyWithWorkerImpl implements $_FormValueCopyWithWorker {
+  _$_FormValueCopyWithWorkerImpl(this.that);
+
+  @override
+  _FormValue call({dynamic name, dynamic provider}) {
+    return _FormValue(
+        name: name as String? ?? that.name,
+        provider: provider as _ProviderOption? ?? that.provider);
+  }
+
+  final _FormValue that;
+}
+
+extension $_FormValueCopyWith on _FormValue {
+  $_FormValueCopyWithWorker get copyWith => _$copyWith;
+  $_FormValueCopyWithWorker get _$copyWith =>
+      _$_FormValueCopyWithWorkerImpl(this);
+}
+
+abstract class $_StateCopyWithWorker {
+  _State call(
+      {_FormValue? formValue,
+      Collection? result,
+      bool? isExporting,
+      ExceptionEvent? error});
+}
+
+class _$_StateCopyWithWorkerImpl implements $_StateCopyWithWorker {
+  _$_StateCopyWithWorkerImpl(this.that);
+
+  @override
+  _State call(
+      {dynamic formValue,
+      dynamic result = copyWithNull,
+      dynamic isExporting,
+      dynamic error = copyWithNull}) {
+    return _State(
+        formValue: formValue as _FormValue? ?? that.formValue,
+        result: result == copyWithNull ? that.result : result as Collection?,
+        isExporting: isExporting as bool? ?? that.isExporting,
+        error: error == copyWithNull ? that.error : error as ExceptionEvent?);
+  }
+
+  final _State that;
+}
+
+extension $_StateCopyWith on _State {
+  $_StateCopyWithWorker get copyWith => _$copyWith;
+  $_StateCopyWithWorker get _$copyWith => _$_StateCopyWithWorkerImpl(this);
+}
+
+// **************************************************************************
+// NpLogGenerator
+// **************************************************************************
+
+extension _$_WrappedExportCollectionDialogStateNpLog
+    on _WrappedExportCollectionDialogState {
+  // ignore: unused_element
+  Logger get _log => log;
+
+  static final log = Logger(
+      "widget.export_collection_dialog._WrappedExportCollectionDialogState");
+}
+
+extension _$_BlocNpLog on _Bloc {
+  // ignore: unused_element
+  Logger get _log => log;
+
+  static final log = Logger("widget.export_collection_dialog._Bloc");
+}
+
+// **************************************************************************
+// ToStringGenerator
+// **************************************************************************
+
+extension _$_SubmitNameToString on _SubmitName {
+  String _$toString() {
+    // ignore: unnecessary_string_interpolations
+    return "_SubmitName {value: $value}";
+  }
+}
+
+extension _$_SubmitProviderToString on _SubmitProvider {
+  String _$toString() {
+    // ignore: unnecessary_string_interpolations
+    return "_SubmitProvider {value: ${value.name}}";
+  }
+}
+
+extension _$_SubmitFormToString on _SubmitForm {
+  String _$toString() {
+    // ignore: unnecessary_string_interpolations
+    return "_SubmitForm {}";
+  }
+}

app/lib/widget/export_collection_dialog/bloc.dart

@@ -0,0 +1,63 @@
+part of '../export_collection_dialog.dart';
+
+@npLog
+class _Bloc extends Bloc<_Event, _State> {
+  _Bloc({
+    required this.account,
+    required this.collectionsController,
+    required this.collection,
+    required this.items,
+  }) : super(_State.init()) {
+    on<_FormEvent>(_onFormEvent);
+  }
+
+  Future<void> _onFormEvent(_FormEvent ev, Emitter<_State> emit) async {
+    _log.info("$ev");
+    if (ev is _SubmitName) {
+      _onSubmitName(ev, emit);
+    } else if (ev is _SubmitProvider) {
+      _onSubmitProvider(ev, emit);
+    } else if (ev is _SubmitForm) {
+      await _onSubmitForm(ev, emit);
+    }
+  }
+
+  void _onSubmitName(_SubmitName ev, Emitter<_State> emit) {
+    emit(state.copyWith(
+      formValue: state.formValue.copyWith(name: ev.value),
+    ));
+  }
+
+  void _onSubmitProvider(_SubmitProvider ev, Emitter<_State> emit) {
+    emit(state.copyWith(
+      formValue: state.formValue.copyWith(provider: ev.value),
+    ));
+  }
+
+  Future<void> _onSubmitForm(_SubmitForm ev, Emitter<_State> emit) async {
+    emit(state.copyWith(isExporting: true));
+    try {
+      final exporter = CollectionExporter(account, collectionsController,
+          collection, items, state.formValue.name);
+      final Collection result;
+      switch (state.formValue.provider) {
+        case _ProviderOption.appAlbum:
+          result = await exporter.asAlbum();
+          break;
+        case _ProviderOption.ncAlbum:
+          result = await exporter.asNcAlbum();
+          break;
+      }
+      emit(state.copyWith(result: result));
+    } catch (e, stackTrace) {
+      _log.severe("[_onSubmitForm] Failed while exporting", e, stackTrace);
+    } finally {
+      emit(state.copyWith(isExporting: false));
+    }
+  }
+
+  final Account account;
+  final CollectionsController collectionsController;
+  final Collection collection;
+  final List<CollectionItem> items;
+}

app/lib/widget/export_collection_dialog/state_event.dart

@@ -0,0 +1,71 @@
+part of '../export_collection_dialog.dart';
+
+@genCopyWith
+class _FormValue {
+  const _FormValue({
+    this.name = "",
+    this.provider = _ProviderOption.appAlbum,
+  });
+
+  final String name;
+  final _ProviderOption provider;
+}
+
+@genCopyWith
+class _State {
+  const _State({
+    required this.formValue,
+    this.result,
+    required this.isExporting,
+    this.error,
+  });
+
+  factory _State.init() {
+    return const _State(
+      formValue: _FormValue(),
+      isExporting: false,
+    );
+  }
+
+  final _FormValue formValue;
+  final Collection? result;
+  final bool isExporting;
+
+  final ExceptionEvent? error;
+}
+
+abstract class _Event {
+  const _Event();
+}
+
+abstract class _FormEvent implements _Event {
+  const _FormEvent();
+}
+
+@toString
+class _SubmitName extends _FormEvent {
+  const _SubmitName(this.value);
+
+  @override
+  String toString() => _$toString();
+
+  final String value;
+}
+
+@toString
+class _SubmitProvider extends _FormEvent {
+  const _SubmitProvider(this.value);
+
+  @override
+  String toString() => _$toString();
+
+  final _ProviderOption value;
+}
+
+@toString
+class _SubmitForm extends _FormEvent {
+  const _SubmitForm();
+
+  @override
+  String toString() => _$toString();
+}