added cargo files

PinePods-0.8.2/mobile/lib/bloc/search/search_bloc.dart

@@ -0,0 +1,96 @@
+// Copyright 2020 Ben Hills and the project contributors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:pinepods_mobile/bloc/bloc.dart';
+import 'package:pinepods_mobile/bloc/search/search_state_event.dart';
+import 'package:pinepods_mobile/services/podcast/podcast_service.dart';
+import 'package:pinepods_mobile/state/bloc_state.dart';
+import 'package:connectivity_plus/connectivity_plus.dart';
+import 'package:logging/logging.dart';
+import 'package:podcast_search/podcast_search.dart' as pcast;
+import 'package:rxdart/rxdart.dart';
+
+/// This BLoC interacts with the [PodcastService] to search for podcasts for
+/// a given term and to fetch the current podcast charts.
+class SearchBloc extends Bloc {
+  final log = Logger('SearchBloc');
+  final PodcastService podcastService;
+
+  /// Add to the Sink to trigger a search using the [SearchEvent].
+  final BehaviorSubject<SearchEvent> _searchInput = BehaviorSubject<SearchEvent>();
+
+  /// Add to the Sink to fetch the current podcast top x.
+  final BehaviorSubject<int> _chartsInput = BehaviorSubject<int>();
+
+  /// Stream of the current search results, be it from search or charts.
+  Stream<BlocState<pcast.SearchResult>>? _searchResults;
+
+  /// Cache of last results.
+  pcast.SearchResult? _resultsCache;
+
+  SearchBloc({required this.podcastService}) {
+    _init();
+  }
+
+  void _init() {
+    _searchResults = _searchInput.switchMap<BlocState<pcast.SearchResult>>(
+      (SearchEvent event) => _search(event),
+    );
+  }
+
+  /// Takes the [SearchEvent] to perform either a search, chart fetch or clearing
+  /// of the current results cache.
+  ///
+  /// To improve resilience, when performing a search the current network status is
+  /// checked. a [BlocErrorState] is pushed if we have no connectivity.
+  Stream<BlocState<pcast.SearchResult>> _search(SearchEvent event) async* {
+    if (event is SearchClearEvent) {
+      yield BlocDefaultState();
+    } else if (event is SearchChartsEvent) {
+      yield BlocLoadingState();
+
+      _resultsCache ??= await podcastService.charts(size: 10);
+
+      yield BlocPopulatedState<pcast.SearchResult>(results: _resultsCache);
+    } else if (event is SearchTermEvent) {
+      final term = event.term;
+
+      if (term.isEmpty) {
+        yield BlocNoInputState();
+      } else {
+        yield BlocLoadingState();
+
+        // Check we have network
+        var connectivityResult = await Connectivity().checkConnectivity();
+
+        // TODO: Docs do not recommend this approach as a reliable way to
+        //       determine if network is available.
+        if (connectivityResult.contains(ConnectivityResult.none)) {
+          yield BlocErrorState(error: BlocErrorType.connectivity);
+        } else {
+          final results = await podcastService.search(term: term);
+
+          // Was the search successful?
+          if (results.successful) {
+            yield BlocPopulatedState<pcast.SearchResult>(results: results);
+          } else {
+            yield BlocErrorState();
+          }
+        }
+      }
+    }
+  }
+
+  @override
+  void dispose() {
+    _searchInput.close();
+    _chartsInput.close();
+  }
+
+  void Function(SearchEvent) get search => _searchInput.add;
+
+  Stream<BlocState>? get results => _searchResults;
+}