feat(import): adopt files that are already in a library

tests/test_import_flow.py

@@ -1294,3 +1294,37 @@ def test_bulk_move_delete_and_count(client):
                           json={"ids": ids[1:]}).json() == {"deleted": 2}
     assert client.get("/api/requests/count?status=missing").json() == {"count": 1}
     assert [r["event"] for r in client.get("/api/history").json()] == ["deleted"] * 2
+
+
+def test_adopt_files_already_in_the_library(client):
+    root = client.tmp_path / "audio"
+    lib = client.post("/api/libraries", json={
+        "name": "Audio", "media_type": "audiobook", "root_path": str(root)}).json()["id"]
+    hobbit = client.post("/api/requests", json={
+        "library_id": lib, "title": "Der Hobbit", "authors": "Tolkien"}).json()["id"]
+    known = client.post("/api/requests", json={
+        "library_id": lib, "title": "Momo", "authors": "Ende"}).json()["id"]
+    for folder in ("Tolkien/Der Hobbit", "Ende/Momo"):
+        (root / folder).mkdir(parents=True)
+        for i in (1, 2):
+            (root / folder / f"{i:02d}.mp3").write_bytes(b"")
+    (root / "Tolkien" / "Notizen.epub").write_bytes(b"")  # other media type
+
+    # Momo already points at its folder, so only the Hobbit is offered
+    adopted = client.post(f"/api/import/library/{lib}", json={"items": [
+        {"path": str(root / "Ende/Momo"), "request_id": known}]}).json()
+    assert adopted == {"results": [{"path": str(root / "Ende/Momo"), "ok": True}]}
+    items = client.get(f"/api/import/library/{lib}").json()["items"]
+    assert [(i["name"], i["suggested_request_id"]) for i in items] == [("Der Hobbit", hobbit)]
+
+    resp = client.post(f"/api/import/library/{lib}", json={"items": [
+        {"path": items[0]["path"], "request_id": hobbit},
+        {"path": str(root / "Ende/Momo"), "request_id": known},  # no longer open
+        {"path": str(client.downloads), "request_id": hobbit},
+    ]}).json()["results"]
+    assert [r["ok"] for r in resp] == [True, False, False]
+    reqs = {r["id"]: r for r in client.get("/api/requests?status=imported").json()}
+    assert reqs[hobbit]["imported_path"] == str(root / "Tolkien/Der Hobbit")
+    assert (root / "Tolkien/Der Hobbit/01.mp3").exists()  # nothing moved
+    assert client.get(f"/api/import/library/{lib}").json()["items"] == []
+    assert [h["event"] for h in client.get("/api/history").json()] == ["adopted"] * 2