Escolher permissao no upload de conteudo

lib/features/materials/presentation/pages/teacher_materials_page.dart

@@ -178,6 +178,7 @@ class _TeacherMaterialsPageState extends State<TeacherMaterialsPage> {
 
                   final docId = materials[index].id;
                   final url = material['url'] as String?;
+                  final classId = material['classId'] as String?;
 
                   return _buildMaterialCard(
                     docId: docId,
@@ -185,6 +186,7 @@ class _TeacherMaterialsPageState extends State<TeacherMaterialsPage> {
                     fileType: fileType,
                     createdAt: createdAt,
                     url: url,
+                    classId: classId,
                   );
                 },
               );
@@ -355,7 +357,7 @@ class _TeacherMaterialsPageState extends State<TeacherMaterialsPage> {
       final XFile? file = await openFile(acceptedTypeGroups: [pdfTypeGroup]);
       if (file == null) return;
 
-      await _uploadFile(
+      await _pickClassAndUpload(
         filePath: file.path,
         fileName: path.basename(file.path),
         fileType: 'pdf',
@@ -377,7 +379,7 @@ class _TeacherMaterialsPageState extends State<TeacherMaterialsPage> {
       );
       if (image == null) return;
 
-      await _uploadFile(
+      await _pickClassAndUpload(
         filePath: image.path,
         fileName: path.basename(image.path),
         fileType: 'image',
@@ -399,7 +401,7 @@ class _TeacherMaterialsPageState extends State<TeacherMaterialsPage> {
       );
       if (photo == null) return;
 
-      await _uploadFile(
+      await _pickClassAndUpload(
         filePath: photo.path,
         fileName: path.basename(photo.path),
         fileType: 'image',
@@ -411,10 +413,148 @@ class _TeacherMaterialsPageState extends State<TeacherMaterialsPage> {
     }
   }
 
+  Future<void> _pickClassAndUpload({
+    required String filePath,
+    required String fileName,
+    required String fileType,
+  }) async {
+    final currentUser = AuthService.currentUser;
+    if (currentUser == null) {
+      _showErrorSnackBar('Utilizador não autenticado');
+      return;
+    }
+
+    // Carregar as turmas do professor
+    List<Map<String, String>> teacherClasses = [];
+    try {
+      final snapshot = await _firestore
+          .collection('classes')
+          .where('teacherId', isEqualTo: currentUser.uid)
+          .orderBy('createdAt', descending: true)
+          .get();
+      teacherClasses = snapshot.docs.map((doc) {
+        final data = doc.data();
+        return {'id': doc.id, 'name': (data['name'] as String? ?? doc.id)};
+      }).toList();
+    } catch (_) {}
+
+    if (!mounted) return;
+
+    // Se o professor não tem turmas, fazer upload sem associar turma
+    if (teacherClasses.isEmpty) {
+      await _uploadFile(
+        filePath: filePath,
+        fileName: fileName,
+        fileType: fileType,
+      );
+      return;
+    }
+
+    // Mostrar diálogo de seleção de turma
+    String? selectedClassId = await showDialog<String>(
+      context: context,
+      builder: (dialogContext) {
+        String? picked;
+        return StatefulBuilder(
+          builder: (context, setDialogState) => AlertDialog(
+            shape: RoundedRectangleBorder(
+              borderRadius: BorderRadius.circular(16),
+            ),
+            title: const Text(
+              'Escolher Turma',
+              style: TextStyle(fontWeight: FontWeight.bold),
+            ),
+            content: Column(
+              mainAxisSize: MainAxisSize.min,
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                const Text(
+                  'Seleciona a turma que terá acesso a este material:',
+                  style: TextStyle(fontSize: 14),
+                ),
+                const SizedBox(height: 16),
+                DropdownButtonFormField<String>(
+                  value: picked,
+                  isExpanded: true,
+                  decoration: InputDecoration(
+                    filled: true,
+                    fillColor: Theme.of(
+                      context,
+                    ).colorScheme.surfaceContainerHighest,
+                    border: OutlineInputBorder(
+                      borderRadius: BorderRadius.circular(12),
+                      borderSide: BorderSide.none,
+                    ),
+                    enabledBorder: OutlineInputBorder(
+                      borderRadius: BorderRadius.circular(12),
+                      borderSide: BorderSide.none,
+                    ),
+                    focusedBorder: OutlineInputBorder(
+                      borderRadius: BorderRadius.circular(12),
+                      borderSide: BorderSide(
+                        color: Theme.of(context).colorScheme.primary,
+                        width: 2,
+                      ),
+                    ),
+                    contentPadding: const EdgeInsets.symmetric(
+                      horizontal: 12,
+                      vertical: 10,
+                    ),
+                  ),
+                  hint: const Text('Seleciona a turma'),
+                  items: teacherClasses
+                      .map(
+                        (c) => DropdownMenuItem<String>(
+                          value: c['id'],
+                          child: Text(c['name']!),
+                        ),
+                      )
+                      .toList(),
+                  onChanged: (value) =>
+                      setDialogState(() => picked = value),
+                ),
+              ],
+            ),
+            actions: [
+              TextButton(
+                onPressed: () => Navigator.of(dialogContext).pop(null),
+                child: const Text('Cancelar'),
+              ),
+              ElevatedButton(
+                onPressed: picked == null
+                    ? null
+                    : () => Navigator.of(dialogContext).pop(picked),
+                style: ElevatedButton.styleFrom(
+                  backgroundColor: const Color(0xFFF68D2D),
+                  foregroundColor: Colors.white,
+                  shape: RoundedRectangleBorder(
+                    borderRadius: BorderRadius.circular(10),
+                  ),
+                ),
+                child: const Text('Confirmar'),
+              ),
+            ],
+          ),
+        );
+      },
+    );
+
+    // Se cancelou o diálogo, não fazer upload
+    if (selectedClassId == null) return;
+
+    await _uploadFile(
+      filePath: filePath,
+      fileName: fileName,
+      fileType: fileType,
+      classId: selectedClassId,
+    );
+  }
+
   Future<void> _uploadFile({
     required String filePath,
     required String fileName,
     required String fileType,
+    String? classId,
   }) async {
     final currentUser = FirebaseAuth.instance.currentUser;
     if (currentUser == null) {
@@ -443,12 +583,18 @@ class _TeacherMaterialsPageState extends State<TeacherMaterialsPage> {
       final downloadUrl = await ref.getDownloadURL();
 
       // Criar documento no Firestore
-      await FirebaseFirestore.instance.collection('materials').add({
+      final materialData = <String, dynamic>{
         'teacherId': uid,
         'fileName': cleanFileName,
         'url': downloadUrl,
         'createdAt': FieldValue.serverTimestamp(),
-      });
+      };
+      if (classId != null && classId.isNotEmpty) {
+        materialData['classId'] = classId;
+      }
+      await FirebaseFirestore.instance
+          .collection('materials')
+          .add(materialData);
 
       if (mounted) {
         _showSuccessSnackBar('Material enviado com sucesso!');
@@ -569,12 +715,25 @@ class _TeacherMaterialsPageState extends State<TeacherMaterialsPage> {
     );
   }
 
+  Future<String?> _getClassName(String classId) async {
+    try {
+      final doc = await _firestore.collection('classes').doc(classId).get();
+      if (doc.exists) {
+        return doc.data()?['name'] as String?;
+      }
+      return null;
+    } catch (_) {
+      return null;
+    }
+  }
+
   Widget _buildMaterialCard({
     required String docId,
     required String fileName,
     required String fileType,
     required Timestamp? createdAt,
     String? url,
+    String? classId,
   }) {
     IconData iconData;
     Color iconColor;
@@ -635,13 +794,58 @@ class _TeacherMaterialsPageState extends State<TeacherMaterialsPage> {
           maxLines: 1,
           overflow: TextOverflow.ellipsis,
         ),
-        subtitle: Text(
+        subtitle: classId != null
-          formattedDate,
+            ? FutureBuilder<String?>(
-          style: const TextStyle(
+                future: _getClassName(classId),
-            color: Color(0xFF718096),
+                builder: (context, snap) {
-            fontSize: 13,
+                  final className = snap.data;
-          ),
+                  return Column(
-        ),
+                    crossAxisAlignment: CrossAxisAlignment.start,
+                    mainAxisSize: MainAxisSize.min,
+                    children: [
+                      Text(
+                        formattedDate,
+                        style: const TextStyle(
+                          color: Color(0xFF718096),
+                          fontSize: 13,
+                        ),
+                      ),
+                      if (className != null) ...[
+                        const SizedBox(height: 2),
+                        Row(
+                          children: [
+                            const Icon(
+                              Icons.school_outlined,
+                              size: 12,
+                              color: Color(0xFF82C9BD),
+                            ),
+                            const SizedBox(width: 4),
+                            Flexible(
+                              child: Text(
+                                className,
+                                style: const TextStyle(
+                                  color: Color(0xFF82C9BD),
+                                  fontSize: 12,
+                                  fontWeight: FontWeight.w500,
+                                ),
+                                maxLines: 1,
+                                overflow: TextOverflow.ellipsis,
+                              ),
+                            ),
+                          ],
+                        ),
+                      ],
+                    ],
+                  );
+                },
+              )
+            : Text(
+                formattedDate,
+                style: const TextStyle(
+                  color: Color(0xFF718096),
+                  fontSize: 13,
+                ),
+              ),
         trailing: IconButton(
           icon: const Icon(Icons.delete_outline, color: Colors.red),
           tooltip: 'Eliminar',