File drops from the file manager insert at the drop position

The table already computed and emitted the drop row for external URL
drops, but PlaylistView._on_files_dropped threw it away, so imported
files always appended. Thread it through: playlist_view.files_dropped
gains a row slot (None = append), MainWindow.import_files and
file_importer.import_paths take an optional position and hand it to
add_tracks_to_playlist, which already supported positional insert.
Files already in the library dedup to the existing track and insert at
the drop position without duplicating the library entry.

lintunes/gui/main_window.py

@@ -314,16 +314,18 @@ class MainWindow(QMainWindow):
         if paths:
             self.import_files([Path(p) for p in paths])
 
-    def import_files(self, paths, playlist_pid: str = ""):
+    def import_files(self, paths, playlist_pid: str = "",
+                     position: int | None = None):
         self.statusBar().showMessage(f"Importing {len(paths)} item(s)…")
         imported = file_importer.import_paths(
-            paths, self._music_import_dir(), self._manager, playlist_pid)
+            paths, self._music_import_dir(), self._manager, playlist_pid,
+            position)
         self.statusBar().showMessage(f"Imported {len(imported)} track(s)", 5000)
         if imported:
             self._library_view.reload()
 
-    def _import_files_to_playlist(self, paths, pid):
-        self.import_files([Path(p) for p in paths], pid)
+    def _import_files_to_playlist(self, paths, pid, position=None):
+        self.import_files([Path(p) for p in paths], pid, position)
 
     # ---- album art download ----
 

lintunes/gui/playlist_view.py

@@ -9,7 +9,7 @@ from lintunes.gui.playlist_ops import add_tracks_with_dup_check
 class PlaylistView(TableSettingsMixin, QWidget):
     play_requested = pyqtSignal(list, int)
     info_requested = pyqtSignal(list)
-    files_dropped = pyqtSignal(list, str)  # paths, playlist pid
+    files_dropped = pyqtSignal(list, str, object)  # paths, pid, row or None
     show_in_playlist_requested = pyqtSignal(int, str)  # track_id, playlist pid
 
     def __init__(self, manager, parent=None):
@@ -124,7 +124,8 @@ class PlaylistView(TableSettingsMixin, QWidget):
 
     def _on_files_dropped(self, paths, drop_row):
         if self._editable():
-            self.files_dropped.emit(paths, self._playlist.persistent_id)
+            self.files_dropped.emit(
+                paths, self._playlist.persistent_id, drop_row)
 
     def _on_remove(self, rows):
         if self._editable():

lintunes/importers/file_importer.py

@@ -97,8 +97,10 @@ def import_file(source: Path, music_dir: Path, manager,
 
 
 def import_paths(paths: list[Path], music_dir: Path, manager,
-                 playlist_pid: str = "") -> list[Track]:
-    """Import files and directories (recursively); optionally add to a playlist."""
+                 playlist_pid: str = "",
+                 position: int | None = None) -> list[Track]:
+    """Import files and directories (recursively); optionally add to a
+    playlist, inserting at `position` (None = append)."""
     files: list[Path] = []
     for path in paths:
         path = Path(path)
@@ -119,5 +121,6 @@ def import_paths(paths: list[Path], music_dir: Path, manager,
             imported.append(track)
 
     if playlist_pid and imported:
-        manager.add_tracks_to_playlist(playlist_pid, [t.track_id for t in imported])
+        manager.add_tracks_to_playlist(
+            playlist_pid, [t.track_id for t in imported], position)
     return imported

tests/test_round18.py

@@ -99,3 +99,75 @@ class TestVisualizerGrayColor:
     def test_visualizer_row_in_preferences_dialog(self, qapp):
         from lintunes.gui.preferences_dialog import _COLOR_ROWS
         assert "color_visualizer_gray" in [key for key, _label in _COLOR_ROWS]
+
+
+# --------------------------------------------------------------------------
+# 2. External file drops insert at the drop position
+# --------------------------------------------------------------------------
+
+def _seeded_manager(tmp_path, track_ids=(1, 2, 3)):
+    from lintunes.models import Library, Track
+    from lintunes.library_manager import LibraryManager
+    tracks = {tid: Track(track_id=tid, name=f"T{tid}") for tid in track_ids}
+    return LibraryManager(Library(tracks=tracks), tmp_path / "data")
+
+
+class TestFileDropPosition:
+    def test_import_paths_inserts_at_position(self, qapp, tmp_path, mp3_file):
+        from lintunes.importers import file_importer
+        manager = _seeded_manager(tmp_path)
+        playlist = manager.create_playlist("Drops")
+        manager.add_tracks_to_playlist(playlist.persistent_id, [1, 2, 3])
+
+        imported = file_importer.import_paths(
+            [mp3_file], tmp_path / "music", manager,
+            playlist.persistent_id, position=1)
+
+        assert len(imported) == 1
+        new_id = imported[0].track_id
+        assert playlist.track_ids == [1, new_id, 2, 3]
+
+    def test_import_paths_default_appends(self, qapp, tmp_path, mp3_file):
+        from lintunes.importers import file_importer
+        manager = _seeded_manager(tmp_path)
+        playlist = manager.create_playlist("Drops")
+        manager.add_tracks_to_playlist(playlist.persistent_id, [1, 2])
+
+        imported = file_importer.import_paths(
+            [mp3_file], tmp_path / "music", manager, playlist.persistent_id)
+
+        assert playlist.track_ids == [1, 2, imported[0].track_id]
+
+    def test_duplicate_file_inserts_without_new_track(self, qapp, tmp_path,
+                                                      mp3_file):
+        from lintunes.importers import file_importer
+        manager = _seeded_manager(tmp_path)
+        existing = file_importer.import_file(
+            mp3_file, tmp_path / "music", manager)
+        playlist = manager.create_playlist("Drops")
+        manager.add_tracks_to_playlist(playlist.persistent_id, [1, 2])
+        count_before = len(manager.library.tracks)
+
+        imported = file_importer.import_paths(
+            [mp3_file], tmp_path / "music", manager,
+            playlist.persistent_id, position=0)
+
+        assert imported[0].track_id == existing.track_id
+        assert playlist.track_ids == [existing.track_id, 1, 2]
+        assert len(manager.library.tracks) == count_before
+
+    def test_playlist_view_relays_drop_row(self, qapp, tmp_path):
+        from lintunes.gui.playlist_view import PlaylistView
+        manager = _seeded_manager(tmp_path)
+        playlist = manager.create_playlist("Drops")
+        view = PlaylistView(manager)
+        view.show_playlist(playlist)
+        received = []
+        view.files_dropped.connect(
+            lambda paths, pid, row: received.append((paths, pid, row)))
+
+        view._on_files_dropped(["/x.mp3"], 2)
+        view._on_files_dropped(["/y.mp3"], None)
+
+        assert received == [(["/x.mp3"], playlist.persistent_id, 2),
+                            (["/y.mp3"], playlist.persistent_id, None)]