Add sort selection

app/playlists.py

@@ -270,13 +270,22 @@ class PlaylistTab(QTableWidget):
         self.hide_or_show_played_tracks()
 
     def _add_context_menu(
-        self, text: str, action: Callable, disabled: bool = False
-    ) -> QAction:
+        self,
+        text: str,
+        action: Callable,
+        disabled: bool = False,
+        parent_menu: Optional[QMenu] = None,
+    ) -> Optional[QAction]:
         """
         Add item to self.menu
         """
 
-        menu_item = self.menu.addAction(text)
+        if parent_menu is None:
+            parent_menu = self.menu
+
+        menu_item = parent_menu.addAction(text)
+        if not menu_item:
+            return None
         menu_item.setDisabled(disabled)
         menu_item.triggered.connect(action)
 
@@ -1073,6 +1082,30 @@ class PlaylistTab(QTableWidget):
         # ----------------------
         self.menu.addSeparator()
 
+        # Sort
+        sort_menu = self.menu.addMenu("Sort")
+        self._add_context_menu(
+            "by title", lambda: self._sort_selection(TITLE), parent_menu=sort_menu
+        )
+        self._add_context_menu(
+            "by artist", lambda: self._sort_selection(ARTIST), parent_menu=sort_menu
+        )
+        self._add_context_menu(
+            "by duration", lambda: self._sort_selection(DURATION), parent_menu=sort_menu
+        )
+        self._add_context_menu(
+            "by last played",
+            lambda: self._sort_selection(LASTPLAYED),
+            parent_menu=sort_menu,
+        )
+        if sort_menu:
+            sort_menu.setEnabled(self._sortable())
+
+        # Build submenu
+
+        # ----------------------
+        self.menu.addSeparator()
+
         # Info
         if track_row:
             self._add_context_menu("Info", lambda: self._info_row(track_id))
@@ -2184,6 +2217,82 @@ class PlaylistTab(QTableWidget):
 
         return item
 
+    def _sortable(self) -> bool:
+        """
+        Return True if the selection is sortable. That means:
+        - at least two rows selected
+        - selected rows are contiguous
+        - selected rows do not include any header rows
+        """
+
+        selectionModel = self.selectionModel()
+        if not selectionModel:
+            return False
+        source_rows = selectionModel.selectedRows()
+        sorted_source_rows = sorted([a.row() for a in source_rows])
+        if len(sorted_source_rows) < 2:
+            return False
+
+        if sorted_source_rows != list(
+            range(min(sorted_source_rows), max(sorted_source_rows) + 1)
+        ):
+            return False
+
+        for row in sorted_source_rows:
+            if self._get_row_track_id(row) == 0:
+                return False
+
+        return True
+
+    def _sort_selection(self, sort_column: int) -> None:
+        """
+        Algorithm:
+        - check row selection is contiguous; return if not
+        - copy (row-number, sort-field) to a list
+        - sort the list by sort-field
+        - create a new row after the selection
+        - iterate the list and move items to new row
+        - create another new row and repeat until all rows moved
+        - delete old rows
+        """
+
+        # Check selection is contiguous
+        selectionModel = self.selectionModel()
+        if not selectionModel:
+            return
+        source_rows = selectionModel.selectedRows()
+        if not self._sortable():
+            return
+
+        # Copy (row-number, sort-field) to a list
+        sorted_rows = []
+        for index in source_rows:
+            sort_item = self.item(index.row(), sort_column)
+            if sort_item:
+                sorted_rows.append((index.row(), sort_item.text()))
+                print(f"{sort_item.text()=}")
+
+        # Sort the list
+        sorted_rows.sort(key=lambda row: row[1])
+
+        # Move rows
+        source_row_numbers = [a[0] for a in sorted_rows]
+        next_row = max(source_row_numbers) + 1
+        for source_row_number in source_row_numbers:
+            self.insertRow(next_row)
+            for column in range(self.columnCount()):
+                self.setItem(next_row, column, self.takeItem(source_row_number, column))
+            next_row += 1
+
+        # Remove source rows
+        for i in reversed(source_rows):
+            self.removeRow(i.row())
+
+        # Save playlist
+        # with Session() as session:
+        #     self.save_playlist(session)
+        #     self._update_start_end_times(session)
+
     def _track_time_between_rows(
         self, session: scoped_session, from_plr: PlaylistRows, to_plr: PlaylistRows
     ) -> int: