Preserve courses with pending rooms and report precise graduate import errors

mobile/lib/features/school/school_page_adapter.dart

@@ -9,8 +9,32 @@ import '../../domain/school_term.dart';
 import 'school_navigation_policy.dart';
 
 class UnsupportedSchoolLayout implements Exception {
+  const UnsupportedSchoolLayout({
+    this.code = 'layout_unknown',
+    this.row,
+    this.column,
+  });
+  final String code;
+  final int? row, column;
+  String get description => switch (code) {
+    'origin_invalid' => '页面来源不符合学校课表要求',
+    'payload_too_large' => '课表页面超过读取大小限制',
+    'table_missing' => '未找到课表表格',
+    'semester_missing' => '课表学期信息缺失',
+    'row_count_invalid' => '课表时段行数不符合预期',
+    'weekday_header_invalid' => '星期表头格式不符合预期',
+    'row_cell_count_invalid' => '课表时段单元格不完整',
+    'period_header_invalid' => '课表节次表头无法识别',
+    'cell_id_invalid' => '课程单元格的星期或节次标识异常',
+    'course_record_invalid' => '课程名称、教师或课程字段格式无法识别',
+    'period_mismatch' => '课程节次与所在时段不一致',
+    'weeks_invalid' => '上课周次格式无法识别',
+    'unsafe_markup' => '课程单元格包含不支持的网页内容',
+    'empty_timetable' => '课表尚无可识别的课程安排',
+    _ => '学校课表格式暂不支持',
+  };
   @override
-  String toString() => '未识别到完整的学校课表，当前课表保持不变。请在课表查询页面保存 HTML 后重试。';
+  String toString() => '$description（$code），当前课表保持不变。请在反馈中附带学校HTML和日志。';
 }
 
 /// Reads the supplied graduate-system table as data; never executes its scripts.
@@ -22,28 +46,42 @@ class SchoolPageAdapter {
   }) {
     try {
       if (!SchoolNavigationPolicy.isTimetable(origin) ||
-          source == CourseSource.demo ||
-          utf8.encode(content).length > 2 * 1024 * 1024) {
-        throw UnsupportedSchoolLayout();
+          source == CourseSource.demo) {
+        throw const UnsupportedSchoolLayout(code: 'origin_invalid');
+      }
+      if (utf8.encode(content).length > 2 * 1024 * 1024) {
+        throw const UnsupportedSchoolLayout(code: 'payload_too_large');
       }
       final document = html.parse(content);
       final table = document.querySelector('#tbl');
       final selected = document.querySelector('#drpxq option[selected]');
       final term = selected?.attributes['value'];
-      if (table == null ||
-          term == null ||
+      if (table == null) {
+        throw const UnsupportedSchoolLayout(code: 'table_missing');
+      }
+      if (term == null ||
           !RegExp(r'^\d+$').hasMatch(term) ||
           selected!.text.trim().isEmpty) {
-        throw UnsupportedSchoolLayout();
+        throw const UnsupportedSchoolLayout(code: 'semester_missing');
       }
       final rows = table.querySelectorAll('tr');
       const weekdays = ['节次', '星期一', '星期二', '星期三', '星期四', '星期五', '星期六', '星期日'];
-      if (rows.length != 6 || rows.first.children.length != 8) {
-        throw UnsupportedSchoolLayout();
+      if (rows.length != 6) {
+        throw const UnsupportedSchoolLayout(code: 'row_count_invalid');
+      }
+      if (rows.first.children.length != 8) {
+        throw const UnsupportedSchoolLayout(
+          code: 'weekday_header_invalid',
+          row: 0,
+        );
       }
       for (var i = 0; i < 8; i++) {
         if (rows.first.children[i].text.trim() != weekdays[i]) {
-          throw UnsupportedSchoolLayout();
+          throw UnsupportedSchoolLayout(
+            code: 'weekday_header_invalid',
+            row: 0,
+            column: i,
+          );
         }
       }
       final courses = <String, Course>{};
@@ -52,28 +90,79 @@ class SchoolPageAdapter {
       for (var row = 0; row < starts.length; row++) {
         final first = starts[row], last = first == 9 ? 11 : first + 1;
         final cells = rows[row + 1].children;
-        if (cells.length != 8 ||
-            cells.first.id != 't0$first' ||
+        if (cells.length != 8) {
+          throw UnsupportedSchoolLayout(
+            code: 'row_cell_count_invalid',
+            row: row + 1,
+          );
+        }
+        if (cells.first.id != 't0$first' ||
             cells.first.text.trim() != '$first-$last节') {
-          throw UnsupportedSchoolLayout();
+          throw UnsupportedSchoolLayout(
+            code: 'period_header_invalid',
+            row: row + 1,
+          );
         }
         for (var day = 1; day <= 7; day++) {
           final cell = cells[day];
-          if (cell.id != 't$day$first') throw UnsupportedSchoolLayout();
-          for (final line in _lines(cell)) {
+          if (cell.id != 't$day$first') {
+            throw UnsupportedSchoolLayout(
+              code: 'cell_id_invalid',
+              row: row + 1,
+              column: day,
+            );
+          }
+          final List<String> lines;
+          try {
+            lines = _lines(cell);
+          } on UnsupportedSchoolLayout catch (error) {
+            throw UnsupportedSchoolLayout(
+              code: error.code,
+              row: row + 1,
+              column: day,
+            );
+          }
+          for (final line in lines) {
             final record = RegExp(
-              r'^(\d+)/(.+?)/(\d+(?:\.\d+)?)/(\d+(?:\.\d+)?)/([^/]+)/([^/]+)周/(\d+)[~～-](\d+)节/(.+)$',
+              r'^([A-Za-z0-9][A-Za-z0-9_.-]*)\s*/(.+?)/\s*(\d+(?:\.\d+)?)\s*/\s*(\d+(?:\.\d+)?)\s*/([^/]+)/([^/]+)周/(\d+)[~～-](\d+)节/(.*)$',
             ).firstMatch(line);
-            if (record == null ||
-                int.parse(record[7]!) != first ||
+            if (record == null) {
+              throw UnsupportedSchoolLayout(
+                code: 'course_record_invalid',
+                row: row + 1,
+                column: day,
+              );
+            }
+            if (int.parse(record[7]!) != first ||
                 int.parse(record[8]!) != last) {
-              throw UnsupportedSchoolLayout();
+              throw UnsupportedSchoolLayout(
+                code: 'period_mismatch',
+                row: row + 1,
+                column: day,
+              );
             }
             final code = record[1]!,
                 name = record[2]!.trim(),
                 teacher = record[5]!.trim(),
-                room = record[9]!.trim();
-            final weeks = _weeks(record[6]!);
+                rawRoom = record[9]!.trim(),
+                room = rawRoom.isEmpty ? '教室待定' : rawRoom;
+            if (name.isEmpty || teacher.isEmpty) {
+              throw UnsupportedSchoolLayout(
+                code: 'course_record_invalid',
+                row: row + 1,
+                column: day,
+              );
+            }
+            final Set<int> weeks;
+            try {
+              weeks = _weeks(record[6]!);
+            } on UnsupportedSchoolLayout catch (error) {
+              throw UnsupportedSchoolLayout(
+                code: error.code,
+                row: row + 1,
+                column: day,
+              );
+            }
             final identity = jsonEncode([
               term,
               code,
@@ -101,12 +190,15 @@ class SchoolPageAdapter {
               endPeriod: last,
               weeks: {...?previous?.weeks, ...weeks},
               source: source,
+              notes: rawRoom.isEmpty ? '学校未提供教室，请以学校最新安排为准并在公布后刷新课表。' : '',
             );
           }
         }
       }
       // An empty DOM can be an expired session or an incomplete response.
-      if (courses.isEmpty) throw UnsupportedSchoolLayout();
+      if (courses.isEmpty) {
+        throw const UnsupportedSchoolLayout(code: 'empty_timetable');
+      }
       return ImportDraft(
         courses: List.unmodifiable(courses.values),
         explicitlyEmpty: false,
@@ -132,7 +224,7 @@ class SchoolPageAdapter {
           buffer.write('\n');
         } else {
           if (node.localName == 'script' || node.localName == 'style') {
-            throw UnsupportedSchoolLayout();
+            throw const UnsupportedSchoolLayout(code: 'unsafe_markup');
           }
           for (final child in node.nodes) {
             visit(child);
@@ -157,11 +249,13 @@ class SchoolPageAdapter {
     for (final part in text.split(RegExp('[,，、]'))) {
       final range = RegExp(r'^\s*(\d+)(?:\s*[-~～]\s*(\d+))?\s*$')
           .firstMatch(part);
-      if (range == null) throw UnsupportedSchoolLayout();
+      if (range == null) {
+        throw const UnsupportedSchoolLayout(code: 'weeks_invalid');
+      }
       final first = int.parse(range[1]!),
           last = int.parse(range[2] ?? range[1]!);
       if (first < 1 || last > 30 || last < first) {
-        throw UnsupportedSchoolLayout();
+        throw const UnsupportedSchoolLayout(code: 'weeks_invalid');
       }
       result.addAll(List.generate(last - first + 1, (i) => first + i));
     }

mobile/lib/features/school/school_session.dart

@@ -174,6 +174,8 @@ class SchoolSession extends ChangeNotifier {
   bool _routeClosed = false;
   int _pollsLeft = 0;
   int? _probeGeneration;
+  UnsupportedSchoolLayout? _lastLayoutFailure;
+  int? _layoutFailureGeneration;
   SchoolConnectionState connectionState = SchoolConnectionState.signedOut;
   bool _loading = false,
       hasOpened = false,
@@ -334,9 +336,16 @@ class SchoolSession extends ChangeNotifier {
   String get _findingMessage => requestingExams ? '正在查找考试安排，请稍候' : '正在查找课表，请稍候';
   void _armTimeout() {
     _timeout?.cancel();
-    _timeout = Timer(
-      const Duration(seconds: 45),
-      () => _failure('查找超时，请检查学校页面后重试。已有数据保持不变。', code: 'read_timeout'),
+    _timeout = Timer(const Duration(seconds: 45), _finishReadFailure);
+  }
+
+  void _finishReadFailure() {
+    final error = _layoutFailureGeneration == _pageGeneration
+        ? _lastLayoutFailure
+        : null;
+    _failure(
+      error == null ? '查找超时，请检查学校页面后重试。已有数据保持不变。' : '课表读取未完成：$error',
+      code: error?.code ?? 'read_timeout',
     );
   }
 
@@ -396,7 +405,7 @@ class SchoolSession extends ChangeNotifier {
     }
     _poll?.cancel();
     if (_pollsLeft-- <= 0) {
-      if (finding) _failure('查找超时，请检查学校页面后重试。已有数据保持不变。', code: 'read_timeout');
+      if (finding) _finishReadFailure();
       return;
     }
     _poll = Timer(const Duration(milliseconds: 750), () {
@@ -500,6 +509,8 @@ class SchoolSession extends ChangeNotifier {
             // gets only its recognized fragment with the canonical table path.
             final draft = await _reader.read(_target, () async => page.html);
             if (!hasOpened || generation != _pageGeneration) return;
+            _lastLayoutFailure = null;
+            _layoutFailureGeneration = null;
             if (draft.schoolTerm != selectedTerm) {
               DiagnosticLog.instance.add(
                 'term_mismatch',
@@ -528,11 +539,24 @@ class SchoolSession extends ChangeNotifier {
           notifyListeners();
           return;
         } catch (error) {
+          if (generation != _pageGeneration) return;
+          if (error is UnsupportedSchoolLayout) {
+            _lastLayoutFailure = error;
+            _layoutFailureGeneration = generation;
+            message =
+                '课表暂未识别：${error.description}。正在等待页面加载完整；若仍失败，请在反馈中附带学校HTML和日志。';
+          }
           DiagnosticLog.instance.add(
             'school_parse_rejected',
             fields: {
               'school': 'graduate',
-              'code': error.runtimeType.toString(),
+              'code': error is UnsupportedSchoolLayout
+                  ? error.code
+                  : error.runtimeType.toString(),
+              if (error is UnsupportedSchoolLayout && error.row != null)
+                'row': error.row,
+              if (error is UnsupportedSchoolLayout && error.column != null)
+                'column': error.column,
             },
           );
           if (generation != _pageGeneration) return;
@@ -595,6 +619,7 @@ class SchoolSession extends ChangeNotifier {
         liveUrl != uri.toString()) {
       throw UnsupportedSchoolLayout();
     }
+    UnsupportedSchoolLayout? rejected;
     for (final page in evidence.pages) {
       if (page.kind != 'timetable') continue;
       SchoolPageDiagnostic.instance.remember(page.html, page.url);
@@ -608,11 +633,12 @@ class SchoolSession extends ChangeNotifier {
         }
         if (draft.schoolTerm != selectedTerm) continue;
         return draft;
-      } on UnsupportedSchoolLayout {
+      } on UnsupportedSchoolLayout catch (error) {
         if (generation != _pageGeneration) rethrow;
+        rejected = error;
       }
     }
-    throw UnsupportedSchoolLayout();
+    throw rejected ?? const UnsupportedSchoolLayout(code: 'table_missing');
   }
 
   Future<void> readCurrentPage() async {

mobile/lib/features/school/undergraduate/activity_data.dart

@@ -54,13 +54,6 @@ List<UndergraduateActivity> parseActivityData(
         i + 1,
       );
     }
-    if (args[5].trim().isEmpty) {
-      throw UndergraduateActivityException(
-        'room_missing',
-        '课程活动未提供教室信息，请附带网页反馈',
-        i + 1,
-      );
-    }
     final bitmap = args[6];
     if (!RegExp(r'^0[01]+$').hasMatch(bitmap) ||
         bitmap.length > 64 ||
@@ -109,7 +102,7 @@ List<UndergraduateActivity> parseActivityData(
         args[1].trim(),
         args[3].substring(0, suffix.start).trim(),
         suffix[1]!,
-        args[5].trim(),
+        args[5].trim().isEmpty ? '教室待定' : args[5].trim(),
         indices,
         weeks,
       ),

mobile/lib/features/school/undergraduate/auth_page.dart

@@ -103,7 +103,13 @@ class _UndergraduateAuthPageState extends State<UndergraduateAuthPage> {
         if (route?.isCurrent == true) Navigator.pop(context);
         messenger.showSnackBar(
           SnackBar(
-            content: Text(exams == null ? '课表已导入，请核对学期开始日。' : '考试信息已更新'),
+            content: Text(
+              exams != null
+                  ? '考试信息已更新'
+                  : draft!.courses.any((c) => c.room == '教室待定')
+                  ? '课表已导入，部分课程教室待定；请核对学期开始日。'
+                  : '课表已导入，请核对学期开始日。',
+            ),
           ),
         );
       } else if (controller.lastError != null) {

mobile/lib/features/school/undergraduate/timetable_adapter.dart

@@ -28,7 +28,8 @@ class UndergraduateTimetableAdapter {
           table = html
               .parse(content)
               .querySelector('#manualArrangeCourseTable');
-      if (table == null || doc.querySelector('input[type="password"]') != null) {
+      if (table == null ||
+          doc.querySelector('input[type="password"]') != null) {
         throw const FormatException('请先在学校网页打开课表');
       }
       final termIds = doc
@@ -161,7 +162,10 @@ class UndergraduateTimetableAdapter {
               weeks: group.weeks,
               source: source,
               courseCode: info?.code ?? a.courseCode,
-              notes: info?.notes ?? '',
+              notes: [
+                if (info?.notes.isNotEmpty == true) info!.notes,
+                if (a.room == '教室待定') '学校未提供教室，请以学校最新安排为准并在公布后刷新课表。',
+              ].join('\n'),
             ),
           );
         }