feat: select school before connecting timetable

mobile/lib/app/app_version.dart

@@ -1,2 +1,2 @@
-const appVersion = '0.6.1';
-const appBuildNumber = 16;
+const appVersion = '0.6.2';
+const appBuildNumber = 17;

mobile/lib/app/hepan_app.dart

@@ -14,6 +14,7 @@ import '../features/exams/exams_page.dart';
 import '../features/timetable/timetable_page.dart';
 import '../features/profile/profile_page.dart';
 import '../features/school/school_session.dart';
+import '../features/school/school_selection_page.dart';
 
 class HepanApp extends StatelessWidget {
   const HepanApp({
@@ -66,6 +67,16 @@ class _Shell extends StatefulWidget {
 
 class _ShellState extends State<_Shell> with WidgetsBindingObserver {
   int _tab = 0;
+  bool _openingSchool = false;
+  SupportedSchool? _selectedSchool;
+  // Earlier imports all belong to UESTC graduate; reuse their existing term
+  // and session without requiring students to choose again on every refresh.
+  SupportedSchool? get _knownSchool =>
+      _selectedSchool ??
+      (widget.controller.snapshot.schoolTerm != null ||
+              widget.school?.canLogout == true
+          ? SupportedSchool.uestcGraduate
+          : null);
   void _selectTab(int index) {
     if (index == _tab) return;
     setState(() => _tab = index);
@@ -121,7 +132,41 @@ class _ShellState extends State<_Shell> with WidgetsBindingObserver {
     }
   }
 
-  void _school({bool exams = false, bool chooseTerm = false}) {
+  Future<void> _school({
+    bool exams = false,
+    bool chooseTerm = false,
+    bool selectSchool = false,
+  }) async {
+    if (_openingSchool) return;
+    _openingSchool = true;
+    try {
+      var selected = _knownSchool;
+      if (selectSchool || selected == null) {
+        selected = await Navigator.push<SupportedSchool>(
+          context,
+          MaterialPageRoute<SupportedSchool>(
+            builder: (_) => SchoolSelectionPage(selected: _knownSchool),
+          ),
+        );
+        if (!mounted || selected == null) return;
+        setState(() => _selectedSchool = selected);
+      }
+      if (!mounted) return;
+      // The only current connector is the existing UESTC graduate workflow.
+      // A new catalog option must provide its own connector here.
+      switch (selected) {
+        case SupportedSchool.uestcGraduate:
+          await _openSchool(exams: exams, chooseTerm: chooseTerm);
+      }
+    } finally {
+      _openingSchool = false;
+    }
+  }
+
+  Future<void> _openSchool({
+    bool exams = false,
+    bool chooseTerm = false,
+  }) async {
     if (widget.schoolBuilder != null) {
       final term = widget.controller.snapshot.schoolTerm;
       if (exams) {
@@ -135,12 +180,12 @@ class _ShellState extends State<_Shell> with WidgetsBindingObserver {
           chooseTerm: chooseTerm || term == null,
         );
       }
-      Navigator.push(
+      await Navigator.push(
         context,
         MaterialPageRoute<void>(builder: (_) => widget.schoolBuilder!()),
       );
     } else {
-      showDialog<void>(
+      await showDialog<void>(
         context: context,
         builder: (context) => AlertDialog(
           title: const Text('学校认证'),
@@ -275,7 +320,8 @@ class _ShellState extends State<_Shell> with WidgetsBindingObserver {
                           ProfilePage(
                             controller: widget.controller,
                             feedbackSender: widget.feedbackSender,
-                            onLogin: _school,
+                            onLogin: () => _school(selectSchool: true),
+                            schoolName: _knownSchool?.label,
                             onUpdateTerm: () => _school(chooseTerm: true),
                             authStatus: widget.school?.statusLabel ?? '未登录',
                             logoutLabel: widget.school?.logoutFailed == true

mobile/lib/features/exams/exams_page.dart

@@ -118,7 +118,7 @@ class ExamsPage extends StatelessWidget {
           ),
           const SizedBox(height: 12),
           const Text(
-            '连接研究生系统，或导入学校考试页面的 HTML。',
+            '选择学校连接教务系统，或导入学校考试页面的 HTML。',
             textAlign: TextAlign.center,
             style: TextStyle(fontSize: 13, height: 1.8),
           ),

mobile/lib/features/profile/profile_page.dart

@@ -18,6 +18,7 @@ class ProfilePage extends StatelessWidget {
     super.key,
     required this.controller,
     required this.onLogin,
+    this.schoolName,
     this.authStatus = '未登录',
     this.onLogout,
     this.logoutLabel = '退出学校登录',
@@ -26,6 +27,7 @@ class ProfilePage extends StatelessWidget {
   });
   final AppController controller;
   final VoidCallback onLogin;
+  final String? schoolName;
   final VoidCallback? onLogout;
   final VoidCallback? onUpdateTerm;
   final String authStatus, logoutLabel;
@@ -98,12 +100,12 @@ class ProfilePage extends StatelessWidget {
               ),
               const SizedBox(height: 16),
               const Text(
-                '连接学校课表',
+                '学校课表',
                 style: TextStyle(fontSize: 20, fontWeight: FontWeight.w700),
               ),
               const SizedBox(height: 7),
               Text(
-                '电子科技大学 · 研究生\n$authStatus',
+                '${schoolName ?? '选择学校后连接教务系统'}\n$authStatus',
                 style: TextStyle(
                   fontSize: 12,
                   height: 1.8,
@@ -115,7 +117,7 @@ class ProfilePage extends StatelessWidget {
                 width: double.infinity,
                 child: FilledButton(
                   onPressed: onLogin,
-                  child: Text(onLogout == null ? '登录学校账户' : '打开学校课表'),
+                  child: const Text('选择学校'),
                 ),
               ),
               if (onLogout != null)

mobile/lib/features/school/school_selection_page.dart

@@ -0,0 +1,60 @@
+import 'package:flutter/material.dart';
+
+import '../../app/app_theme.dart';
+
+/// Only list schools whose login and import workflow is available.
+enum SupportedSchool {
+  uestcGraduate('电子科技大学（研究生）', '研究生课表与考试安排');
+
+  const SupportedSchool(this.label, this.description);
+  final String label, description;
+}
+
+class SchoolSelectionPage extends StatelessWidget {
+  const SchoolSelectionPage({super.key, this.selected});
+
+  final SupportedSchool? selected;
+
+  @override
+  Widget build(BuildContext context) => Scaffold(
+    appBar: AppBar(title: const Text('选择学校')),
+    body: SafeArea(
+      top: false,
+      child: ListView(
+        padding: const EdgeInsets.fromLTRB(22, 16, 22, 24),
+        children: [
+          Text(
+            '选择你的学校，登录后导入课表和考试。',
+            style: TextStyle(fontSize: 13, color: ink.withValues(alpha: 0.6)),
+          ),
+          const SizedBox(height: 20),
+          for (final school in SupportedSchool.values) ...[
+            SurfaceCard(
+              padding: EdgeInsets.zero,
+              child: ListTile(
+                contentPadding: const EdgeInsets.symmetric(
+                  horizontal: 16,
+                  vertical: 12,
+                ),
+                leading: const Icon(Icons.school_rounded, color: river),
+                title: Text(
+                  school.label,
+                  style: const TextStyle(fontWeight: FontWeight.w600),
+                ),
+                subtitle: Text(school.description),
+                trailing: Icon(
+                  school == selected
+                      ? Icons.check_circle_rounded
+                      : Icons.chevron_right_rounded,
+                  color: river,
+                ),
+                onTap: () => Navigator.pop(context, school),
+              ),
+            ),
+            const SizedBox(height: 12),
+          ],
+        ],
+      ),
+    ),
+  );
+}