Added watchdog support

bagheeraview.py

@@ -78,6 +78,7 @@ from widgets import (
     FavoritesWidget
 )
 from metadatamanager import load_common_metadata
+from filesystemwatcher import FileSystemWatcher
 
 
 class ShortcutHelpDialog(QDialog):
@@ -1067,6 +1068,11 @@ class MainWindow(QMainWindow):
         self.progress_bar.hide()
         bot.addWidget(self.progress_bar)
 
+        self.fs_watcher_status_lbl = QLabel()
+        self.fs_watcher_status_lbl.setToolTip(UITexts.FS_WATCHER_TOOLTIP)
+        self.fs_watcher_status_lbl.hide()
+        bot.addWidget(self.fs_watcher_status_lbl)
+
         # Timer to hide progress bar with delay
         self.hide_progress_timer = QTimer(self)
         self.hide_progress_timer.setSingleShot(True)
@@ -1236,12 +1242,6 @@ class MainWindow(QMainWindow):
         self.favorites_tab.favorites_changed.connect(
             self.shortcut_controller.refresh_favorite_shortcuts)
 
-        # Initialize FileSystemWatcher
-        self.fs_watcher = FileSystemWatcher()
-        self.fs_watcher.file_created.connect(self.on_fs_file_created)
-        self.fs_watcher.file_deleted.connect(self.on_fs_file_deleted)
-        self.fs_watcher.file_modified.connect(self.on_fs_file_modified)
-
         self.main_dock.setWidget(self.tags_tabs)
         self.addDockWidget(Qt.RightDockWidgetArea, self.main_dock)
 
@@ -1289,6 +1289,30 @@ class MainWindow(QMainWindow):
         self.thumbnail_view.verticalScrollBar().valueChanged.connect(
             self._on_scroll_interaction)
 
+        # Initialize FileSystemWatcher
+        self.fs_watcher = FileSystemWatcher()
+        self.fs_watcher.file_created.connect(self.on_fs_file_created)
+        self.fs_watcher.file_deleted.connect(self.on_fs_file_deleted)
+        self.fs_watcher.file_modified.connect(self.on_fs_file_modified)
+        self.fs_watcher.directory_modified.connect(self.on_fs_directory_modified)
+        self.fs_watcher.file_moved.connect(self.on_fs_file_moved)
+        self.fs_watcher.directory_moved.connect(self.on_fs_directory_moved)
+        self.fs_watcher.monitoring_status_changed.connect(
+            self.on_fs_watcher_status_changed)
+
+        # Batching for file creation events
+        self._fs_created_queue = set()
+        self._fs_created_timer = QTimer(self)
+        self._fs_created_timer.setSingleShot(True)
+        self._fs_created_timer.setInterval(1000)  # 1 second debounce
+        self._fs_created_timer.timeout.connect(self._process_fs_created_batch)
+
+        # Debounce timer for full refreshes on directory modifications
+        self._fs_dir_refresh_timer = QTimer(self)
+        self._fs_dir_refresh_timer.setSingleShot(True)
+        self._fs_dir_refresh_timer.setInterval(2500)  # 2.5 seconds debounce
+        self._fs_dir_refresh_timer.timeout.connect(self.refresh_content)
+
         # Initial configuration loading
         self.load_config()
         self.load_full_history()
@@ -1607,15 +1631,17 @@ class MainWindow(QMainWindow):
         # 5. Start scanning all parent directories of the images in the layout
         unique_dirs = list({str(Path(p).parent) for p in paths})
         for d in unique_dirs:
+            if d not in paths:
                 paths.append(d)
+
         self.start_scan([p.strip() for p in paths if p.strip()
                          and os.path.exists(os.path.expanduser(p.strip()))],
                         select_paths=select_paths)
+
         if search_text:
             self.search_input.setEditText(search_text)
 
     # --- UI and Menu Logic ---
-
     def show_main_menu(self):
         """Displays the main application menu."""
         menu = QMenu(self)
@@ -1817,6 +1843,7 @@ class MainWindow(QMainWindow):
     def perform_shutdown(self):
         """Performs cleanup operations before the application closes."""
         self.is_cleaning = True
+        self.fs_watcher.stop()
         # 1. Stop all worker threads interacting with the cache
 
         # Signal all threads to stop first
@@ -2059,7 +2086,13 @@ class MainWindow(QMainWindow):
 
     def find_and_select_path(self, path_to_select):
         """Finds an item by its path in the model and selects it using a cache."""
-        if not path_to_select or path_to_select not in self._path_to_model_index:
+        if not path_to_select:
+            return False
+
+        # Ensure path is normalized for reliable cache lookup
+        path_to_select = os.path.abspath(os.path.expanduser(path_to_select))
+
+        if path_to_select not in self._path_to_model_index:
             return False
 
         persistent_index = self._path_to_model_index[path_to_select]
@@ -2072,6 +2105,11 @@ class MainWindow(QMainWindow):
         proxy_index = self.proxy_model.mapFromSource(source_index)
 
         if proxy_index.isValid():
+            # Optimization: skip if already selected and current to avoid
+            # unnecessary signals and view updates.
+            if self.thumbnail_view.currentIndex() == proxy_index and \
+               self.thumbnail_view.selectionModel().isSelected(proxy_index):
+                return True
             self.set_selection(proxy_index)
             return True
 
@@ -2368,16 +2406,16 @@ class MainWindow(QMainWindow):
                                          inode=new_inode, device_id=new_dev)
 
                 # Update model item
-                for row in range(self.thumbnail_model.rowCount()):
+                if path in self._path_to_model_index:
-                    item = self.thumbnail_model.item(row)
+                    p_idx = self._path_to_model_index[path]
-                    if item and item.data(PATH_ROLE) == path:
+                    if p_idx.isValid():
+                        item = self.thumbnail_model.itemFromIndex(QModelIndex(p_idx))
                         item.setIcon(QIcon(QPixmap.fromImage(thumb_img)))
                         item.setData(new_mtime, MTIME_ROLE)
                         item.setData(new_inode, INODE_ROLE)
                         item.setData(new_dev, DEVICE_ROLE)
                         self._update_internal_data(path, qi=thumb_img, mtime=new_mtime,
                                                    inode=new_inode, dev=new_dev)
-                        break
         except Exception:
             pass
 
@@ -2418,6 +2456,7 @@ class MainWindow(QMainWindow):
             self.proxy_model.clear_cache()
             self._model_update_queue.clear()
             self._model_update_timer.stop()
+            self.fs_watcher.clear_paths()
 
         # Stop any pending hide action from previous scan
         self.hide_progress_timer.stop()
@@ -2437,6 +2476,12 @@ class MainWindow(QMainWindow):
             self.scanner.set_auto_load(True)
         self._is_loading = True
         self.scanner.images_found.connect(self.collect_found_images)
+
+        # Add directories to file system watcher
+        for p in paths:
+            if os.path.isdir(os.path.abspath(os.path.expanduser(p))):
+                self.fs_watcher.add_path(os.path.abspath(os.path.expanduser(p)))
+
         self.scanner.progress_percent.connect(self.update_progress_bar)
         self.scanner.progress_msg.connect(self.status_lbl.setText)
         self.scanner.more_files_available.connect(self.more_files_available)
@@ -2625,12 +2670,9 @@ class MainWindow(QMainWindow):
         # Check for Header match
         # target format: ('HEADER', (key, header_text, count))
         if isinstance(target, tuple) and len(target) == 2 and target[0] == 'HEADER':
-            _, (_, header_text, _) = target
-            # Strict match including group name to ensure roles are updated
             target_group_name = target[1][0]
             return (item.data(ITEM_TYPE_ROLE) == 'header' and
-                    item.data(GROUP_NAME_ROLE) == target_group_name and
+                    item.data(GROUP_NAME_ROLE) == target_group_name)
-                    item.data(DIR_ROLE) == header_text)
 
         # Check for Thumbnail match
         # target format: (path, qi, mtime, tags, rating, inode, dev)
@@ -2641,48 +2683,94 @@ class MainWindow(QMainWindow):
         return False
 
     def _get_group_info(self, path, mtime, rating):
-        """Calculates the grouping key and display name for a file.
+        """Calculates the grouping key and display name for a file with optimized
-
+        caching."""
-        Args:
+        # Determine resolution criteria for shared caching across all files in same
-            path (str): File path.
+        # group
-            mtime (float): Modification time.
-            rating (int): Rating value.
-
-        Returns:
-            tuple: (stable_group_key, display_name)
-        """
-        cache_key = (path, mtime, rating)
-        if cache_key in self._group_info_cache:
-            return self._group_info_cache[cache_key]
-
-        stable_group_key = None
-        display_name = None
-
         if self.proxy_model.group_by_folder:
-            stable_group_key = display_name = os.path.dirname(path)
+            crit = os.path.dirname(path)
-        elif self.proxy_model.group_by_day:
+            mode = 'F'
-            stable_group_key = display_name = datetime.fromtimestamp(
-                mtime).strftime("%Y-%m-%d")
-        elif self.proxy_model.group_by_week:
-            dt = datetime.fromtimestamp(mtime)
-            stable_group_key = dt.strftime("%Y-%W")
-            display_name = UITexts.GROUP_BY_WEEK_FORMAT.format(
-                year=dt.strftime("%Y"), week=dt.strftime("%W"))
-        elif self.proxy_model.group_by_month:
-            dt = datetime.fromtimestamp(mtime)
-            stable_group_key = dt.strftime("%Y-%m")
-            display_name = dt.strftime("%B %Y").capitalize()
-        elif self.proxy_model.group_by_year:
-            stable_group_key = display_name = datetime.fromtimestamp(
-                mtime).strftime("%Y")
         elif self.proxy_model.group_by_rating:
-            r = rating if rating is not None else 0
+            crit = (rating + 1) // 2 if rating is not None else 0
-            stars = (r + 1) // 2
+            mode = 'R'
-            stable_group_key = str(stars)
+        else:
-            display_name = UITexts.GROUP_BY_RATING_FORMAT.format(stars=stars)
+            # Date modes: use datetime object parts as hashable criteria
+            dt = datetime.fromtimestamp(int(mtime) if mtime else 0)
+            if self.proxy_model.group_by_day:
+                crit = (dt.year, dt.month, dt.day)
+                mode = 'D'
+            elif self.proxy_model.group_by_week:
+                crit = (dt.year, int(dt.strftime("%W")))
+                mode = 'W'
+            elif self.proxy_model.group_by_month:
+                crit = (dt.year, dt.month)
+                mode = 'M'
+            elif self.proxy_model.group_by_year:
+                crit = dt.year
+                mode = 'Y'
+            else:
+                return (None, None)
 
-        self._group_info_cache[cache_key] = (stable_group_key, display_name)
+        # Shared cache by criteria ensures expensive formatting happens only once per
-        return stable_group_key, display_name
+        # group
+        shared_key = (crit, mode)
+        if shared_key in self._group_info_cache:
+            return self._group_info_cache[shared_key]
+
+        # Perform actual calculation
+        if mode == 'F':
+            res = (crit, crit)
+        elif mode == 'R':
+            res = (str(crit), UITexts.GROUP_BY_RATING_FORMAT.format(stars=crit))
+        else:
+            if mode == 'D':
+                sk = dn = dt.strftime("%Y-%m-%d")
+            elif mode == 'W':
+                sk = dt.strftime("%Y-%W")
+                dn = UITexts.GROUP_BY_WEEK_FORMAT.format(
+                    year=dt.strftime("%Y"), week=dt.strftime("%W"))
+            elif mode == 'M':
+                sk = dt.strftime("%Y-%m")
+                dn = dt.strftime("%B %Y").capitalize()
+            else:  # Year
+                sk = dn = dt.strftime("%Y")
+            res = (sk, dn)
+
+        self._group_info_cache[shared_key] = res
+        return res
+
+    def _find_sorted_index_in_data(self, new_item_data):
+        """Finds the correct index to insert an item to keep found_items_data sorted."""
+        mode = self.sort_combo.currentText()
+        rev = "↓" in mode
+        sort_by_name = "Name" in mode
+
+        def get_key(item):
+            # item structure: (path, qi, mtime, tags, rating, inode, dev)
+            path, _, mtime, _, _, _, _ = item
+            if sort_by_name:
+                return os.path.basename(path).lower()
+            return mtime if mtime is not None else 0
+
+        target_key = get_key(new_item_data)
+
+        # Binary search for the insertion point (O(log N))
+        lo = 0
+        hi = len(self.found_items_data)
+        while lo < hi:
+            mid = (lo + hi) // 2
+            mid_key = get_key(self.found_items_data[mid])
+            if not rev:
+                if mid_key < target_key:
+                    lo = mid + 1
+                else:
+                    hi = mid
+            else:
+                if mid_key > target_key:
+                    lo = mid + 1
+                else:
+                    hi = mid
+        return lo
 
     def rebuild_view(self, full_reset=False):
         """
@@ -2779,13 +2867,26 @@ class MainWindow(QMainWindow):
                     self.thumbnail_model.clear()
                     self._path_to_model_index.clear()
 
-                # Optimize grouped insertion: Decorate-Sort-Group
+                # 1. Decorate: Calculate group info once per item with local memoization
-                # 1. Decorate: Calculate group info once per item
                 decorated_data = []
+                local_memo = {}
+                # Cache grouping flags to avoid property lookups in loop
+                g_folder = self.proxy_model.group_by_folder
+
                 for item in self.found_items_data:
                     # item structure: (path, qi, mtime, tags, rating, inode, dev)
+                    path, _, mtime, _, rating, _, _ = item
+
+                    # Local cache key: path for folders, (int_mtime, rating) for others
+                    m_key = path if g_folder else (int(mtime) if mtime else 0, rating)
+
+                    if m_key in local_memo:
+                        stable_key, display_name = local_memo[m_key]
+                    else:
                         stable_key, display_name = self._get_group_info(
-                        item[0], item[2], item[4])
+                            path, mtime, rating)
+                        local_memo[m_key] = (stable_key, display_name)
+
                     # Use empty string for None keys to ensure sortability
                     sort_key = stable_key if stable_key is not None else ""
                     decorated_data.append((sort_key, display_name, item))
@@ -2824,13 +2925,82 @@ class MainWindow(QMainWindow):
                 total_targets = len(target_structure)
                 new_items_batch = []
 
+                # Optimization: Pre-calculate sets for fast lookup of needed items
+                target_paths_set = {t[0] for t in target_structure
+                                    if isinstance(t, tuple) and len(t) >= 5}
+                target_headers_set = {t[1][0] for t in target_structure
+                                      if isinstance(t, tuple)
+                                      and len(t) == 2 and t[0] == 'HEADER'}
+
                 while target_idx < total_targets:
                     target = target_structure[target_idx]
                     current_item = self.thumbnail_model.item(model_idx)
 
                     if self._match_item(target, current_item):
+                        # Si es una cabecera, actualizamos el texto por si cambió el
+                        # contador
+                        if isinstance(target, tuple) and target[0] == 'HEADER':
+                            _, (_, header_text, _) = target
+                            if current_item.data(DIR_ROLE) != header_text:
+                                current_item.setData(header_text, DIR_ROLE)
+
                         model_idx += 1
                         target_idx += 1
+                        continue
+
+                    # 1. Identify and remove stale items (items in model but not in
+                    # target structure)
+                    if current_item:
+                        is_needed = False
+                        if current_item.data(ITEM_TYPE_ROLE) == 'thumbnail':
+                            is_needed = current_item.data(PATH_ROLE) in target_paths_set
+                        else:  # header
+                            is_needed = current_item.data(GROUP_NAME_ROLE) \
+                                in target_headers_set
+
+                        if not is_needed:
+                            path = current_item.data(PATH_ROLE)
+                            if path and path in self._path_to_model_index:
+                                del self._path_to_model_index[path]
+                            self.thumbnail_model.removeRow(model_idx)
+                            # Stay at same model_idx, check next model item against
+                            # same target
+                            continue
+
+                    # 2. Try to MOVE target from later in the model (reordering
+                    # optimization)
+                    found_model_row = -1
+                    if isinstance(target, tuple) and len(target) >= 5:  # Thumbnail
+                        path = target[0]
+                        p_idx = self._path_to_model_index.get(path)
+                        if p_idx and p_idx.isValid() and p_idx.row() > model_idx:
+                            found_model_row = p_idx.row()
+                    elif isinstance(target, tuple) and target[0] == 'HEADER':
+                        target_group_name = target[1][0]
+                        for r in range(model_idx + 1, self.thumbnail_model.rowCount()):
+                            it = self.thumbnail_model.item(r)
+                            if it and it.data(ITEM_TYPE_ROLE) == 'header' and \
+                               it.data(GROUP_NAME_ROLE) == target_group_name:
+                                found_model_row = r
+                                break
+
+                    if found_model_row != -1:
+                        # Move existing row to current position.
+                        # Persistent indices and selection model will update
+                        # automatically.
+                        self.thumbnail_model.moveRow(QModelIndex(), found_model_row,
+                                                     QModelIndex(), model_idx)
+                        if isinstance(target, tuple) and target[0] == 'HEADER':
+                            _, (_, header_text, _) = target
+                            moved_item = self.thumbnail_model.item(model_idx)
+                            if moved_item and moved_item.data(DIR_ROLE) != header_text:
+                                moved_item.setData(header_text, DIR_ROLE)
+
+                        model_idx += 1
+                        target_idx += 1
+                        continue
+
+                    # 3. Target is truly NEW - use batch insertion
                     else:
                         # Prepare new item
                         if isinstance(target, tuple) and len(target) == 2 \
@@ -2857,12 +3027,21 @@ class MainWindow(QMainWindow):
                         # recalculations
                         while target_idx < total_targets:
                             next_target = target_structure[target_idx]
+
                             # Check if next_target matches current model position
                             # (re-sync)
                             if self._match_item(
                                next_target, self.thumbnail_model.item(model_idx)):
                                 break
 
+                            # Check if next_target is a MOVE (exists elsewhere)
+                            if isinstance(next_target, tuple) and len(next_target) >= 5:
+                                n_p_idx = self._path_to_model_index.get(next_target[0])
+                                if n_p_idx and n_p_idx.isValid() \
+                                   and n_p_idx.row() > model_idx:
+                                    break
+                            # (simplified lookahead: headers always break batch)
+
                             # If not matching, it's another new item to insert
                             if isinstance(next_target, tuple) \
                                and len(next_target) == 2 and next_target[0] == 'HEADER':
@@ -3473,22 +3652,23 @@ class MainWindow(QMainWindow):
             res = load_common_metadata(path)
             tags, rating = res.tags, res.rating
 
-        # Find the item in the source model and update its data
+        # Use cache for O(1) lookup in the source model
-        for row in range(self.thumbnail_model.rowCount()):
+        path = os.path.abspath(os.path.expanduser(path))
-            item = self.thumbnail_model.item(row)
+        if path in self._path_to_model_index:
-            if item and item.data(PATH_ROLE) == path:
+            p_idx = self._path_to_model_index[path]
+            if p_idx.isValid():
+                item = self.thumbnail_model.itemFromIndex(QModelIndex(p_idx))
                 item.setData(tags, TAGS_ROLE)
                 item.setData(rating, RATING_ROLE)
 
                 tooltip_text = f"{os.path.basename(path)}\n{path}"
                 if tags:
                     display_tags = [t.split('/')[-1] for t in tags]
-                    tooltip_text += f"\n{UITexts.TAGS_TAB}: {', '.join(
+                    tooltip_text += f"\n{UITexts.TAGS_TAB}: {', '.join(display_tags)}"
-                        display_tags)}"
                 item.setToolTip(tooltip_text)
 
                 # Notify the view that the data has changed
-                source_idx = self.thumbnail_model.indexFromItem(item)
+                source_idx = QModelIndex(p_idx)
                 self.thumbnail_model.dataChanged.emit(
                     source_idx, source_idx, [TAGS_ROLE, RATING_ROLE])
 
@@ -3497,7 +3677,6 @@ class MainWindow(QMainWindow):
 
                 # Update proxy filter cache to prevent stale filtering
                 self.proxy_model.add_to_cache(path, tags)
-                break
 
         if self.main_dock.isVisible():
             self.on_tags_tab_changed(self.tags_tabs.currentIndex())
@@ -3528,14 +3707,14 @@ class MainWindow(QMainWindow):
             self.thumbnail_view.setGridSize(QSize())
         else:
             self.thumbnail_view.setGridSize(self.delegate.sizeHint(None, None))
-        self.rebuild_view(full_reset=True)
+        self.rebuild_view()
 
         self.save_config()
         self.setFocus()
 
     def on_sort_changed(self):
         """Callback for when the sort order dropdown changes."""
-        self.rebuild_view(full_reset=True)
+        self.rebuild_view()
         self.save_config()
         if hasattr(self, 'history_tab'):
             self.history_tab.refresh_list()
@@ -4274,8 +4453,169 @@ class MainWindow(QMainWindow):
         self.cache.clear_cache()
         self.status_lbl.setText(UITexts.CACHE_CLEARED)
 
+    def on_fs_file_created(self, path):
+        """Handles a new file being created in a monitored directory."""
+        # Add to batch queue and (re)start the debounce timer
+        self._fs_created_queue.add(path)
+        self._fs_created_timer.start()
+
+    def _process_fs_created_batch(self):
+        """Processes all accumulated file creation events at once."""
+        paths = list(self._fs_created_queue)
+        self._fs_created_queue.clear()
+
+        valid_new_items = []
+        for p in paths:
+            p = os.path.abspath(p)
+            if os.path.exists(p) and p not in self._known_paths:
+                if os.path.splitext(p)[1].lower() in constants.IMAGE_EXTENSIONS:
+                    valid_new_items.append(p)
+
+        if not valid_new_items:
+            return
+
+        # If the batch is very large, a full scan is more efficient than individual
+        # stats
+        if len(valid_new_items) > 50:
+            self.refresh_content()
+            return
+
+        # For smaller batches, process metadata and update model
+        for path in valid_new_items:
+            try:
+                res = load_common_metadata(path)
+                stat_res = os.stat(path)
+                mtime = stat_res.st_mtime
+                inode = stat_res.st_ino
+                dev = stat_res.st_dev
+
+                # tuple: (path, qi, mtime, tags, rating, inode, dev)
+                new_item_data = (path, None, mtime, res.tags, res.rating, inode, dev)
+                self.found_items_data.append(new_item_data)
+                self._known_paths.add(path)
+                self.proxy_model.add_to_cache(path, res.tags)
+            except Exception:
+                continue
+
+        # Trigger an incremental rebuild of the view
+        self.rebuild_view()
+
+        # Start background generation for the new items
+        self.generate_missing_thumbnails(self._current_thumb_tier)
+
+        if len(valid_new_items) == 1:
+            msg = f"New file detected: {os.path.basename(valid_new_items[0])}"
+        else:
+            msg = f"Detected {len(valid_new_items)} new files"
+        self.status_lbl.setText(msg)
+
+    def on_fs_file_deleted(self, path):
+        """Handles a file being deleted from a monitored directory."""
+        path = os.path.abspath(path)
+        if path not in self._known_paths:
+            return  # Not a file we're tracking
+
+        # Remove from internal data structures
+        self.found_items_data = [item for item in self.found_items_data
+                                 if item[0] != path]
+        self._known_paths.discard(path)
+        self.proxy_model._data_cache.pop(path, None)
+        self.cache.invalidate_path(path)  # Clear from cache
+
+        # Update any open viewers
+        for w in QApplication.topLevelWidgets():
+            if isinstance(w, ImageViewer):
+                if path in w.controller.image_list:
+                    try:
+                        deleted_idx = w.controller.image_list.index(path)
+                        new_list = list(w.controller.image_list)
+                        new_list.remove(path)
+                        w.refresh_after_delete(new_list, deleted_idx)
+                    except (ValueError, RuntimeError):
+                        pass
+
+        # Invalidate caches that might hold references to the deleted path
+        self._visible_paths_cache = None
+        keys_to_remove = [k for k in self._group_info_cache if k[0] == path]
+        for k in keys_to_remove:
+            del self._group_info_cache[k]
+        self.rebuild_view()
+        self.status_lbl.setText(f"File deleted: {os.path.basename(path)}")
+
+    def on_fs_file_moved(self, old_path, new_path):
+        """Handles a file being renamed or moved."""
+        old_path = os.path.abspath(old_path)
+        new_path = os.path.abspath(new_path)
+
+        is_old_img = os.path.splitext(old_path)[1].lower() in constants.IMAGE_EXTENSIONS
+        is_new_img = os.path.splitext(new_path)[1].lower() in constants.IMAGE_EXTENSIONS
+
+        if is_old_img and is_new_img:
+            if old_path in self._known_paths:
+                self.propagate_rename(old_path, new_path)
+            else:
+                self.on_fs_file_created(new_path)
+        elif is_old_img:
+            # Moved out or renamed to non-image
+            self.on_fs_file_deleted(old_path)
+        elif is_new_img:
+            # Moved in from outside
+            self.on_fs_file_created(new_path)
+
+    def on_fs_file_modified(self, path):
+        """Handles a file being modified in a monitored directory."""
+        path = os.path.abspath(path)
+        if path not in self._known_paths:
+            return  # Not a file we're tracking
+
+        # Invalidate cache and trigger a refresh of its metadata and thumbnail
+        self.cache.invalidate_path(path)
+
+        # Re-read metadata and thumbnail
+        res = load_common_metadata(path)
+        mtime = os.path.getmtime(path)
+        stat_res = os.stat(path)
+        inode = stat_res.st_ino
+        dev = stat_res.st_dev
+
+        # Update internal data and model
+        self._update_internal_data(path, mtime=mtime, tags=res.tags, rating=res.rating,
+                                   inode=inode, dev=dev)
+        self.proxy_model.add_to_cache(path, res.tags)
+        self.rebuild_view()
+        self.status_lbl.setText(f"File modified: {os.path.basename(path)}")
+
+    def on_fs_watcher_status_changed(self, is_monitoring):
+        """Updates the UI indicator for the FileSystemWatcher."""
+        if is_monitoring:
+            self.fs_watcher_status_lbl.setPixmap(
+                QIcon.fromTheme("folder-open").pixmap(16, 16))
+            self.fs_watcher_status_lbl.show()
+        else:
+            self.fs_watcher_status_lbl.hide()
+
+    def on_fs_directory_modified(self, path):
+        """Handles a directory being modified (e.g., new subfolder, mass changes)."""
+        path = os.path.abspath(path)
+
+        # Trigger a debounced full refresh. This is useful for syncing large
+        # external changes (bulk operations, directory deletions) that are
+        # more robustly handled by a full scan than incremental updates.
+        if not self._is_loading and not self.is_cleaning:
+            self._fs_dir_refresh_timer.start()
+
+    def on_fs_directory_moved(self, old_path, new_path):
+        """Handles a directory being renamed or moved."""
+        # For directory moves, a full refresh is the most reliable way to sync
+        # since all child paths have changed and individual file move signals
+        # might not be emitted for every item inside.
+        self.on_fs_directory_modified(new_path)
+
     def propagate_rename(self, old_path, new_path, source_viewer=None):
         """Propagates a file rename across the application."""
+        old_path = os.path.abspath(old_path)
+        new_path = os.path.abspath(new_path)
+
         self._visible_paths_cache = None
         # Update found_items_data to ensure consistency on future rebuilds
         current_tags = None
@@ -4302,15 +4642,16 @@ class MainWindow(QMainWindow):
                 os.path.basename(new_path).lower())
 
         # Update the main model
-        for row in range(self.thumbnail_model.rowCount()):
+        if old_path in self._path_to_model_index:
-            item = self.thumbnail_model.item(row)
+            p_idx = self._path_to_model_index.pop(old_path)
-            if item and item.data(PATH_ROLE) == old_path:
+            if p_idx.isValid():
+                item = self.thumbnail_model.itemFromIndex(QModelIndex(p_idx))
+                if item:
                     item.setData(new_path, PATH_ROLE)
                     item.setText(os.path.basename(new_path))
-                # No need to update the icon, it's the same image data
+                    self._path_to_model_index[new_path] = p_idx
-                source_index = self.thumbnail_model.indexFromItem(item)
+                    source_index = QModelIndex(p_idx)
                     self.thumbnail_model.dataChanged.emit(source_index, source_index)
-                break
 
         # Update the cache entry
         self.cache.rename_entry(old_path, new_path)

constants.py

@@ -33,8 +33,20 @@ PROG_VERSION = "0.9.15-dev"
 PROG_AUTHOR = "Ignacio Serantes"
 
 # --- CACHE SETTINGS ---
-# Maximum number of thumbnails to keep in the in-memory cache.
+# Maximum number of paths to track in the in-memory cache.
-CACHE_MAX_SIZE = 20000
+CACHE_MAX_SIZE = 10000
+
+# Dynamic RAM limit for thumbnails to avoid swapping on low-end systems.
+try:
+    import psutil
+    _total_ram_bytes = psutil.virtual_memory().total
+    # Use 10% of system RAM, clamped between 128MB and 512MB
+    CACHE_MAX_RAM_BYTES = int(max(128 * 1024 * 1024,
+                                  min(512 * 1024 * 1024, _total_ram_bytes * 0.10)))
+except (ImportError, Exception):
+    # Fallback to a safe 256MB if psutil is missing or fails
+    CACHE_MAX_RAM_BYTES = 256 * 1024 * 1024
+
 # Maximum size of the persistent disk cache file.
 # 10 GB limit for persistent cache file
 DISK_CACHE_MAX_BYTES = 10 * 1024 * 1024 * 1024
@@ -814,6 +826,7 @@ _UI_TEXTS = {
         "ERROR_MOVE_FILE": "Could not move file: {}",
         "ERROR_COPY_FILE": "Could not copy file: {}",
         "MOVED_TO": "Moved to {}",
+        "FS_WATCHER_TOOLTIP": "File System Watcher (monitoring active directories)",
         "COPIED_TO": "Copied to {}",
         "ERROR_ROTATE_IMAGE": "Could not rotate image: {}",
     },
@@ -1285,6 +1298,8 @@ _UI_TEXTS = {
         "ERROR_MOVE_FILE": "No se pudo mover el archivo: {}",
         "ERROR_COPY_FILE": "No se pudo copiar el archivo: {}",
         "MOVED_TO": "Movido a {}",
+        "FS_WATCHER_TOOLTIP": "Monitor de Sistema de Archivos (monitoreando "
+        "directorios activos)",
         "COPIED_TO": "Copiado a {}",
         "ERROR_ROTATE_IMAGE": "No se pudo girar la imagen: {}",
     },
@@ -1757,6 +1772,8 @@ _UI_TEXTS = {
         "ERROR_MOVE_FILE": "Non se puido mover o ficheiro: {}",
         "ERROR_COPY_FILE": "Non se puido copiar o ficheiro: {}",
         "MOVED_TO": "Movido a {}",
+        "FS_WATCHER_TOOLTIP": "Monitor do Sistema de Ficheiros (monitoreando "
+        "directorios activos)",
         "COPIED_TO": "Copiado a {}",
         "ERROR_ROTATE_IMAGE": "Non se puido xirar a imaxe: {}",
     }

filesystemwatcher.py

@@ -0,0 +1,203 @@
+import os
+try:
+    from watchdog.observers import Observer
+    from watchdog.events import FileSystemEventHandler
+    HAVE_WATCHDOG = True
+except ImportError:
+    HAVE_WATCHDOG = False
+from PySide6.QtCore import QObject, Signal, QTimer
+from constants import IMAGE_EXTENSIONS
+
+
+class FileSystemWatcher(QObject):
+    """
+    Monitors file system events (created, deleted, modified) for specified directories.
+    Emits signals to notify the main application thread of changes.
+    """
+    file_created = Signal(str)
+    file_deleted = Signal(str)
+    file_modified = Signal(str)
+    _file_modified_from_handler = Signal(str)  # Internal signal from handler thread
+    file_moved = Signal(str, str)
+    monitoring_status_changed = Signal(bool)  # Nuevo: Señal para el estado de monitoreo
+    directory_moved = Signal(str, str)
+    directory_modified = Signal(str)  # For changes that might not be specific files
+
+    _modified_events_queue = {}  # {path: QTimer}
+
+    def __init__(self, parent=None):
+        super().__init__(parent)
+        self._watched_directories = set()
+
+        if HAVE_WATCHDOG:
+            self._observer = Observer()
+            self._event_handler = self._Handler(self)
+            self._observer.start()
+        else:
+            self._observer = None  # Keep observer as None if watchdog is not available
+
+        # Debounce timer for modified events to avoid multiple signals for a single save
+        self._debounce_interval = 500  # milliseconds
+
+        # Connect the internal signal to the debouncing slot
+        if HAVE_WATCHDOG:
+            self._file_modified_from_handler.connect(self._on_file_modified_debounced)
+
+    def _on_file_modified_debounced(self, path):
+        """Slot to handle modified events from the watchdog thread, debounced in the
+        main thread."""
+        # Debounce timer for modified events to avoid multiple signals for a single save
+        if path in self._modified_events_queue:
+            self._modified_events_queue[path].stop()
+        else:
+            # Ensure timer lives in the main thread (parent is self)
+            timer = QTimer(self)
+            timer.setSingleShot(True)
+            timer.setInterval(self._debounce_interval)
+            timer.timeout.connect(lambda p=path: self._emit_modified_after_debounce(p))
+            self._modified_events_queue[path] = timer
+        self._modified_events_queue[path].start()
+
+    def _emit_modified_after_debounce(self, path):
+        """Emits the file_modified signal after the debounce period."""
+        self.file_modified.emit(path)
+        if path in self._modified_events_queue:
+            # Safely delete the QTimer object when done
+            self._modified_events_queue[path].deleteLater()
+            del self._modified_events_queue[path]
+
+    def add_path(self, path):
+        """Adds a directory to be monitored."""
+        if not HAVE_WATCHDOG or self._observer is None:
+            return
+
+        # Normalize and expand path to ensure consistent comparison
+        abs_path = os.path.normpath(os.path.abspath(os.path.expanduser(path)))
+
+        # 1. Check if path is already covered by an existing watch (exact or parent)
+        for watched in self._watched_directories:
+            if abs_path == watched:
+                return
+            parent_prefix = watched if watched.endswith(os.sep) else watched + os.sep
+            if abs_path.startswith(parent_prefix):
+                return  # Path is a subdirectory of an already watched directory
+
+        old_monitoring_state = bool(self._watched_directories)
+
+        # 2. Check if this new path covers existing watches (is a parent of them)
+        # If so, consolidate them into this single parent watch
+        child_prefix = abs_path if abs_path.endswith(os.sep) else abs_path + os.sep
+        covered_children = [w for w in self._watched_directories
+                            if w.startswith(child_prefix)]
+
+        try:
+            if covered_children:
+                self._observer.unschedule_all()
+                for child in covered_children:
+                    self._watched_directories.remove(child)
+                self._watched_directories.add(abs_path)
+                for p in self._watched_directories:
+                    self._observer.schedule(self._event_handler, p, recursive=True)
+                print(f"Consolidated monitoring at parent: {abs_path}")
+            else:
+                self._observer.schedule(self._event_handler, abs_path, recursive=True)
+                self._watched_directories.add(abs_path)
+                print(f"Monitoring: {abs_path}")
+        except Exception as e:
+            print(f"Error scheduling watchdog for {abs_path}: {e}")
+            return
+
+        if not old_monitoring_state and self._watched_directories:
+            self.monitoring_status_changed.emit(True)
+
+    def remove_path(self, path):
+        """Removes a directory from monitoring."""
+        if not HAVE_WATCHDOG or self._observer is None:
+            return
+        abs_path = os.path.normpath(os.path.abspath(os.path.expanduser(path)))
+        if abs_path in self._watched_directories:
+            old_monitoring_state = bool(self._watched_directories)
+            self._observer.unschedule_all()  # Simpler to unschedule all and re-add
+            self._watched_directories.remove(abs_path)
+            for p in list(self._watched_directories):  # Iterate over a copy
+                self._observer.schedule(self._event_handler, p, recursive=True)
+            print(f"Stopped monitoring: {abs_path}")
+            if HAVE_WATCHDOG and old_monitoring_state and not self._watched_directories:
+                self.monitoring_status_changed.emit(False)
+
+    def clear_paths(self):
+        """Clears all monitored paths."""
+        if not HAVE_WATCHDOG or not self._observer:
+            return
+
+        old_monitoring_state = bool(self._watched_directories)
+        self._observer.unschedule_all()
+        self._watched_directories.clear()
+        print("Cleared all monitored paths.")
+        if old_monitoring_state:
+            self.monitoring_status_changed.emit(False)
+
+    def stop(self):
+        """Stops the file system observer."""
+        if HAVE_WATCHDOG and self._observer:
+            self._observer.stop()
+            self._observer.join()
+
+        for timer in self._modified_events_queue.values():
+            timer.stop()
+
+        if HAVE_WATCHDOG:
+            print("FileSystemWatcher stopped.")
+
+    if HAVE_WATCHDOG:
+        class _Handler(FileSystemEventHandler):
+            # Signal to communicate to main thread
+            file_modified_from_thread = Signal(str)
+            """Custom event handler for watchdog events."""
+            def __init__(self, watcher):
+                super().__init__()
+                self.watcher = watcher
+
+            def on_created(self, event):
+                if event.is_directory:
+                    self.watcher.directory_modified.emit(event.src_path)
+                    return
+                if self._is_image_file(event.src_path):
+                    self.watcher.file_created.emit(event.src_path)
+
+            def on_deleted(self, event):
+                if event.is_directory:
+                    self.watcher.directory_modified.emit(event.src_path)
+                    return
+                if self._is_image_file(event.src_path):
+                    self.watcher.file_deleted.emit(event.src_path)
+
+            def on_moved(self, event):
+                if event.is_directory:
+                    self.watcher.directory_moved.emit(event.src_path, event.dest_path)
+                    self.watcher.directory_modified.emit(event.src_path)
+                    self.watcher.directory_modified.emit(event.dest_path)
+                    return
+                self.watcher.file_moved.emit(event.src_path, event.dest_path)
+
+            def on_closed(self, event):
+                if event.is_directory:
+                    self.watcher.directory_modified.emit(event.src_path)
+                    return
+                if self._is_image_file(event.src_path):
+                    self.watcher.file_modified.emit(event.src_path)
+
+            def on_modified(self, event):
+                if event.is_directory:
+                    self.watcher.directory_modified.emit(event.src_path)
+                    return
+                if self._is_image_file(event.src_path):
+                    self.watcher._file_modified_from_handler.emit(event.src_path)
+
+            def _emit_modified(self, path):
+                self.watcher.file_modified.emit(path)
+                if path in self.watcher._modified_events_queue:
+                    del self.watcher._modified_events_queue[path]
+
+            def _is_image_file(self, path):
+                return os.path.splitext(path)[1].lower() in IMAGE_EXTENSIONS

imagescanner.py

@@ -35,8 +35,8 @@ from PySide6.QtCore import (
 from PySide6.QtGui import QImage, QImageReader, QImageIOHandler
 
 from constants import (
-    APP_CONFIG, CACHE_PATH, CACHE_MAX_SIZE, CONFIG_DIR, DISK_CACHE_MAX_BYTES,
+    APP_CONFIG, CACHE_PATH, CACHE_MAX_SIZE, CACHE_MAX_RAM_BYTES, CONFIG_DIR,
-    HAVE_BAGHEERASEARCH_LIB, IMAGE_EXTENSIONS,
+    DISK_CACHE_MAX_BYTES, HAVE_BAGHEERASEARCH_LIB, IMAGE_EXTENSIONS,
     SCANNER_SETTINGS_DEFAULTS, SEARCH_CMD, THUMBNAIL_SIZES,
     UITexts
 )
@@ -646,12 +646,10 @@ class ThumbnailCache(QObject):
     def _ensure_cache_limit(self):
         """Enforces cache size limit by evicting oldest entries.
         Must be called with a write lock held."""
-        # Safety limit: 512MB for thumbnails in RAM to prevent system freeze
-        MAX_RAM_BYTES = 512 * 1024 * 1024
 
         while len(self._thumbnail_cache) > 0 and (
                 len(self._thumbnail_cache) >= CACHE_MAX_SIZE or
-                self._cache_bytes_size > MAX_RAM_BYTES):
+                self._cache_bytes_size > CACHE_MAX_RAM_BYTES):
             oldest_path = next(iter(self._thumbnail_cache))
             cached_sizes = self._thumbnail_cache.pop(oldest_path)
             for img, _ in cached_sizes.values():
@@ -1752,6 +1750,10 @@ class ImageScanner(QThread):
                     batch.append(r.result)
                     self.count += 1
                     images_loaded += 1
+                    # Emit progress every time an image is loaded
+                    if len(self.all_files) > 0:
+                        percent = int((self.count / len(self.all_files)) * 100)
+                        self.progress_percent.emit(percent)
 
             # Clean up runnables
             runnables.clear()
@@ -1796,12 +1798,11 @@ class ImageScanner(QThread):
                                            "scan_batch_size"]))
                 return
 
-            if self.count % 10 == 0:  # Update progress less frequently
+            # Emit progress message less frequently, e.g., every 50 images or at batch
-                self.progress_msg.emit(
+            # end
-                    UITexts.LOADING_SCAN.format(self.count, len(self.all_files)))
+            if self.count % 50 == 0 or images_loaded >= to_load:
-                if len(self.all_files) > 0:
+                self.progress_msg.emit(UITexts.LOADING_SCAN.format(
-                    percent = int((self.count / len(self.all_files)) * 100)
+                    self.count, len(self.all_files)))
-                    self.progress_percent.emit(percent)
 
         self.index = len(self.all_files)
         if batch:

pyproject.toml

@@ -23,6 +23,8 @@ dependencies = [
     "PySide6",
     "lmdb",
     "exiv2",
+    "psutil",
+    "watchdog",
     "mediapipe",
     "face_recognition",
     "face_recognition_models",

requirements.txt

@@ -1,6 +1,8 @@
 PySide6
 lmdb
 exiv2
+psutil
+watchdog
 mediapipe
 face_recognition
 face_recognition_models

setup.py

@@ -14,6 +14,8 @@ setup(
         "PySide6",
         "lmdb",
         "exiv2",
+        "psutil",
+        "watchdog",
         "mediapipe",
         "face_recognition",
         "face_recognition_models",
@@ -33,6 +35,7 @@ setup(
         "imagescanner",
         "imageviewer",
         "imagecontroller",
+        "filesystemwatcher",
         "metadatamanager",
         "propertiesdialog",
         "thumbnailwidget",