add filter by network for legs, add full export for traction

lib/services/api_service.dart

@@ -119,6 +119,45 @@ class ApiService {
     return _processResponse(response);
   }
 
+  Future<ApiBinaryResponse> postBytes(
+    String endpoint,
+    dynamic data, {
+    Map<String, String>? headers,
+    bool includeAuth = true,
+    bool allowRetry = true,
+  }) async {
+    final hasBody = data != null;
+    final response = await _sendWithRetry(
+      () => _client.post(
+        Uri.parse('$baseUrl$endpoint'),
+        headers: _buildHeaders(
+          hasBody ? _jsonHeaders(headers) : headers,
+          includeAuth: includeAuth,
+        ),
+        body: hasBody ? jsonEncode(data) : null,
+      ),
+      allowRetry: allowRetry,
+    );
+
+    if (response.statusCode >= 200 && response.statusCode < 300) {
+      final contentDisposition = response.headers['content-disposition'];
+      return ApiBinaryResponse(
+        bytes: response.bodyBytes,
+        statusCode: response.statusCode,
+        contentType: response.headers['content-type'],
+        filename: _extractFilename(contentDisposition),
+      );
+    }
+
+    final body = _decodeBody(response);
+    final message = _extractErrorMessage(body);
+    throw ApiException(
+      statusCode: response.statusCode,
+      message: message,
+      body: body,
+    );
+  }
+
   Future<dynamic> postMultipartFile(
     String endpoint, {
     required List<int> bytes,

lib/services/data_service/data_service_core.dart

@@ -7,6 +7,7 @@ class _LegFetchOptions {
   final String? dateRangeStart;
   final String? dateRangeEnd;
   final bool unallocatedOnly;
+  final List<String> networkFilter;
 
   const _LegFetchOptions({
     this.limit = 100,
@@ -15,6 +16,7 @@ class _LegFetchOptions {
     this.dateRangeStart,
     this.dateRangeEnd,
     this.unallocatedOnly = false,
+    this.networkFilter = const [],
   });
 }
 
@@ -118,6 +120,7 @@ class DataService extends ChangeNotifier {
   List<String> _stationNetworks = [];
   Map<String, List<String>> _stationCountryNetworks = {};
   DateTime? _stationFiltersFetchedAt;
+  DateTime? _stationNetworksFetchedAt;
   List<String> get stationNetworks => _stationNetworks;
   Map<String, List<String>> get stationCountryNetworks =>
       _stationCountryNetworks;
@@ -391,9 +394,14 @@ class DataService extends ChangeNotifier {
     String? dateRangeEnd,
     bool append = false,
     bool unallocatedOnly = false,
+    List<String> networkFilter = const [],
   }) async {
     _isLegsLoading = true;
     if (!append) {
+      final normalizedNetworks = networkFilter
+          .map((network) => network.trim())
+          .where((network) => network.isNotEmpty)
+          .toList();
       _lastLegsFetch = _LegFetchOptions(
         limit: limit,
         sortBy: sortBy,
@@ -401,6 +409,7 @@ class DataService extends ChangeNotifier {
         dateRangeStart: dateRangeStart,
         dateRangeEnd: dateRangeEnd,
         unallocatedOnly: unallocatedOnly,
+        networkFilter: normalizedNetworks,
       );
     }
     final buffer = StringBuffer(
@@ -415,6 +424,13 @@ class DataService extends ChangeNotifier {
     if (unallocatedOnly) {
       buffer.write('&unallocated_only=true');
     }
+    final networks = networkFilter
+        .map((network) => network.trim())
+        .where((network) => network.isNotEmpty)
+        .toList();
+    for (final network in networks) {
+      buffer.write('&network_filter=${Uri.encodeQueryComponent(network)}');
+    }
     try {
       final json = await api.get('/user/legs${buffer.toString()}');
 
@@ -444,6 +460,7 @@ class DataService extends ChangeNotifier {
       dateRangeStart: _lastLegsFetch.dateRangeStart,
       dateRangeEnd: _lastLegsFetch.dateRangeEnd,
       unallocatedOnly: _lastLegsFetch.unallocatedOnly,
+      networkFilter: _lastLegsFetch.networkFilter,
     );
   }
 
@@ -669,6 +686,7 @@ class DataService extends ChangeNotifier {
     _stationNetworks = [];
     _stationCountryNetworks = {};
     _stationFiltersFetchedAt = null;
+    _stationNetworksFetchedAt = null;
     _notifications = [];
     _isNotificationsLoading = false;
     _userEntriesVisibility = 'private';
@@ -736,6 +754,9 @@ class DataService extends ChangeNotifier {
         final networks = (map['networks'] as List? ?? const [])
             .whereType<String>()
             .toList();
+        networks.sort(
+          (a, b) => a.toLowerCase().compareTo(b.toLowerCase()),
+        );
         final countryNetworksRaw =
             map['country_networks'] as Map? ?? const <String, dynamic>{};
         final countryNetworks = <String, List<String>>{};
@@ -753,6 +774,31 @@ class DataService extends ChangeNotifier {
     }
   }
 
+  Future<void> fetchStationNetworks() async {
+    final now = DateTime.now();
+    final recent = _stationNetworks.isNotEmpty &&
+        ((_stationNetworksFetchedAt != null &&
+                now.difference(_stationNetworksFetchedAt!) <
+                    const Duration(minutes: 30)) ||
+            (_stationFiltersFetchedAt != null &&
+                now.difference(_stationFiltersFetchedAt!) <
+                    const Duration(minutes: 30)));
+    if (recent) return;
+    try {
+      final response = await api.get('/stations/networks');
+      if (response is List) {
+        final networks = response.whereType<String>().toList();
+        networks.sort(
+          (a, b) => a.toLowerCase().compareTo(b.toLowerCase()),
+        );
+        _stationNetworks = networks;
+        _stationNetworksFetchedAt = now;
+      }
+    } catch (e) {
+      debugPrint('Failed to fetch station networks: $e');
+    }
+  }
+
   String _stationKey(List<String> countries, List<String> networks) {
     final c = countries..sort();
     final n = networks..sort();