video enrichment: survive legacy UNIQUE on tmdb_id/tvdb_id (no scan crash)

Existing DBs created before the schema dropped UNIQUE still have shows.tvdb_id /
movies.tmdb_id UNIQUE, so enrichment matching two items to the same id threw
'UNIQUE constraint failed' repeatedly. enrichment_apply now catches the
IntegrityError and retries without the id columns — keeps the existing
(authoritative) id and still records match_status + metadata. Non-destructive
(no table rebuild). Test simulates the legacy unique index.

database/video_database.py

@@ -179,21 +179,39 @@ class VideoDatabase:
         if not spec:
             return
         tbl, idc, sc, ac = spec
-        sets = [f"{sc}=?", f"{ac}=CURRENT_TIMESTAMP"]
-        params = ["matched" if matched else "not_found"]
-        if matched and external_id is not None:
-            sets.append(f"{idc}=?")
-            params.append(external_id)
         allowed = _ENRICH_META_COLS.get(tbl, set())
-        for col, val in (metadata or {}).items():
-            if val is not None and col in allowed:
+        # On legacy DBs tmdb_id/tvdb_id may still carry a UNIQUE index; if a match
+        # would collide with another row's id we drop the id columns and keep the
+        # existing (authoritative) id, still recording status + metadata.
+        id_cols = {"tmdb_id", "tvdb_id", "imdb_id"}
+
+        def build(include_ids):
+            sets = [f"{sc}=?", f"{ac}=CURRENT_TIMESTAMP"]
+            params = ["matched" if matched else "not_found"]
+            if matched and external_id is not None and include_ids:
+                sets.append(f"{idc}=?")
+                params.append(external_id)
+            for col, val in (metadata or {}).items():
+                if val is None or col not in allowed:
+                    continue
+                if not include_ids and col in id_cols:
+                    continue
                 sets.append(f"{col}=?")
                 params.append(val)
-        params.append(item_id)
+            params.append(item_id)
+            return f"UPDATE {tbl} SET {', '.join(sets)} WHERE id=?", params
+
         conn = self._get_connection()
         try:
-            conn.execute(f"UPDATE {tbl} SET {', '.join(sets)} WHERE id=?", params)
-            conn.commit()
+            sql, params = build(True)
+            try:
+                conn.execute(sql, params)
+                conn.commit()
+            except sqlite3.IntegrityError:
+                conn.rollback()
+                sql, params = build(False)   # keep existing id, just record status/metadata
+                conn.execute(sql, params)
+                conn.commit()
         finally:
             conn.close()
 

tests/test_video_database.py

@@ -365,6 +365,23 @@ def test_enrichment_apply_matched_sets_id_status_and_metadata(db):
     assert (row["overview"], row["backdrop_url"], row["imdb_id"]) == ("O", "/b.jpg", "tt1")
 
 
+def test_enrichment_apply_survives_legacy_unique(db):
+    # Simulate a pre-existing DB where tvdb_id still carries a UNIQUE index.
+    with db.connect() as c:
+        c.execute("CREATE UNIQUE INDEX ux_legacy_shows_tvdb ON shows(tvdb_id)")
+        c.commit()
+    a = db.upsert_show_tree("plex", {"server_id": "s1", "title": "A", "seasons": []})
+    b = db.upsert_show_tree("plex", {"server_id": "s2", "title": "B", "seasons": []})
+    db.enrichment_apply("tvdb", "show", a, matched=True, external_id=555, metadata={"overview": "OA"})
+    # b would collide on tvdb_id=555 — must NOT crash; keeps existing id, records the rest.
+    db.enrichment_apply("tvdb", "show", b, matched=True, external_id=555, metadata={"overview": "OB"})
+    with db.connect() as c:
+        ra = c.execute("SELECT tvdb_id, tvdb_match_status FROM shows WHERE id=?", (a,)).fetchone()
+        rb = c.execute("SELECT tvdb_id, tvdb_match_status, overview FROM shows WHERE id=?", (b,)).fetchone()
+    assert (ra["tvdb_id"], ra["tvdb_match_status"]) == (555, "matched")
+    assert rb["tvdb_id"] is None and rb["tvdb_match_status"] == "matched" and rb["overview"] == "OB"
+
+
 def test_enrichment_breakdown_unmatched_retry(db):
     a = db.upsert_movie("plex", {"server_id": "m1", "title": "A"})
     b = db.upsert_movie("plex", {"server_id": "m2", "title": "B"})