add(core): re-apply the naming scheme to imported titles

tests/test_import_flow.py

@@ -687,3 +687,136 @@ def test_search_passes_language_to_the_provider(client, monkeypatch):
     }).json()
     assert seen == {"query": "Game of Thrones", "language": "english"}
     assert res[0]["language"] == "english"
+
+
+def test_folder_of_separate_books_is_flagged(client):
+    """One book per file (a series bought as single titles) still scans as one
+    entry - but gets flagged so the UI can offer to split it."""
+    got = client.downloads / "George R. R. Martin" / "A Game of Thrones"
+    got.mkdir(parents=True)
+    for name in ("1 - A Game of Thrones- A Song of Ice and Fire, Book 1 (Unabridged)",
+                 "2 - A Clash of Kings- A Song of Ice and Fire, Book 2 (Unabridged)",
+                 "A - The World of Ice & Fire - The Untold History of Westeros"):
+        with open(got / f"{name}.mp3", "wb") as f:
+            f.truncate(700 * 1024 * 1024)  # sparse, costs no disk space
+
+    chapters = client.downloads / "Ein Hoerbuch"
+    chapters.mkdir()
+    for i, title in enumerate(["Prolog", "Die Ankunft", "Das Ende"], 1):
+        with open(chapters / f"{i:02d} - {title}.mp3", "wb") as f:
+            f.truncate(25 * 1024 * 1024)
+
+    tracks = client.downloads / "Folge 100"
+    tracks.mkdir()
+    for i in (1, 2, 3):
+        with open(tracks / f"{i:02d} Track.mp3", "wb") as f:
+            f.truncate(200 * 1024 * 1024)
+
+    flags = {i["name"]: i["maybe_separate"]
+             for i in client.get("/api/import/scan").json()["items"]}
+    assert flags == {
+        "A Game of Thrones": True,   # different titles, each big enough
+        "Ein Hoerbuch": False,       # different titles, but chapter sized
+        "Folge 100": False,          # same name beyond the index
+    }
+
+
+def test_split_dirs_still_lists_every_file(client):
+    got = client.downloads / "A Game of Thrones"
+    got.mkdir()
+    for n in (1, 2, 3):
+        (got / f"{n} - Book {n}.mp3").write_bytes(b"")
+    items = client.get("/api/import/scan", params={"split_dirs": True}).json()["items"]
+    assert len(items) == 3
+    assert all(not i["is_dir"] for i in items)
+
+
+def test_relocate_after_fixing_the_series(client):
+    """Audible files Harry Potter under "Wizarding World"; after correcting the
+    series the folder on disk should follow."""
+    root = client.tmp_path / "library" / "english"
+    lib_id = client.post("/api/libraries", json={
+        "name": "english", "media_type": "audiobook", "root_path": str(root),
+        "folder_template": "{Series}/{Title}", "file_template": "{Title}",
+    }).json()["id"]
+    req_id = client.post("/api/requests", json={
+        "library_id": lib_id, "title": "Philosopher's Stone",
+        "series": "Wizarding World", "volume": 1,
+    }).json()["id"]
+
+    src = client.downloads / "hp1"
+    src.mkdir()
+    for i in (1, 2):
+        (src / f"{i:02d}.mp3").write_bytes(b"")
+    dest = client.post("/api/import", json={"items": [{
+        "path": str(src), "is_dir": True,
+        "files": [str(f) for f in sorted(src.iterdir())], "request_id": req_id,
+    }]}).json()["results"][0]["dest"]
+    assert Path(dest) == root / "Wizarding World" / "Philosopher's Stone"
+    # a cover dropped next to the audio must survive the move
+    (Path(dest) / "cover.jpg").write_bytes(b"")
+
+    client.put(f"/api/requests/{req_id}", json={
+        "library_id": lib_id, "title": "Philosopher's Stone",
+        "series": "Harry Potter", "volume": 1,
+    })
+    res = client.post(f"/api/requests/{req_id}/relocate").json()
+    assert res["ok"] and res["moved"]
+    new = root / "Harry Potter" / "Philosopher's Stone"
+    assert Path(res["dest"]) == new
+    assert sorted(p.name for p in new.iterdir()) == [
+        "Philosopher's Stone - Part 01.mp3", "Philosopher's Stone - Part 02.mp3", "cover.jpg",
+    ]
+    assert not (root / "Wizarding World").exists()  # emptied parent is gone
+    assert client.get("/api/requests", params={"status": "imported"}).json()[0][
+        "imported_path"] == str(new)
+
+
+def test_relocate_is_a_no_op_when_nothing_changed(client):
+    root = client.tmp_path / "library" / "l"
+    lib_id = client.post("/api/libraries", json={
+        "name": "L", "media_type": "audiobook", "root_path": str(root),
+        "folder_template": "{Title}", "file_template": "{Title}",
+    }).json()["id"]
+    req_id = client.post("/api/requests",
+                         json={"library_id": lib_id, "title": "Ein Buch"}).json()["id"]
+    src = client.downloads / "buch"
+    src.mkdir()
+    for i in (1, 2):
+        (src / f"{i:02d}.mp3").write_bytes(b"")
+    client.post("/api/import", json={"items": [{
+        "path": str(src), "is_dir": True,
+        "files": [str(f) for f in sorted(src.iterdir())], "request_id": req_id,
+    }]})
+    res = client.post(f"/api/requests/{req_id}/relocate").json()
+    assert res["ok"] and not res["moved"]
+    assert sorted(p.name for p in (root / "Ein Buch").iterdir()) == [
+        "Ein Buch - Part 01.mp3", "Ein Buch - Part 02.mp3",
+    ]
+
+
+def test_relocate_refuses_to_overwrite(client):
+    root = client.tmp_path / "library" / "l"
+    lib_id = client.post("/api/libraries", json={
+        "name": "L", "media_type": "audiobook", "root_path": str(root),
+        "folder_template": "{Title}", "file_template": "{Title}",
+    }).json()["id"]
+    req_id = client.post("/api/requests",
+                         json={"library_id": lib_id, "title": "Erstes"}).json()["id"]
+    src = client.downloads / "b"
+    src.mkdir()
+    (src / "01.mp3").write_bytes(b"")
+    (src / "02.mp3").write_bytes(b"")
+    client.post("/api/import", json={"items": [{
+        "path": str(src), "is_dir": True,
+        "files": [str(f) for f in sorted(src.iterdir())], "request_id": req_id,
+    }]})
+    occupied = root / "Zweites"
+    occupied.mkdir(parents=True)
+    (occupied / "fremd.mp3").write_bytes(b"")
+
+    client.put(f"/api/requests/{req_id}", json={"library_id": lib_id, "title": "Zweites"})
+    res = client.post(f"/api/requests/{req_id}/relocate")
+    assert res.status_code == 409
+    assert (occupied / "fremd.mp3").exists()
+    assert (root / "Erstes" / "Erstes - Part 01.mp3").exists()