Search: say where a matched moment ends

backend/app/routers/search.py

@@ -29,6 +29,9 @@ class SearchHit(BaseModel):
     # Seconds into the asset. Null for a metadata hit, which is about the file rather
     # than a moment in it.
     start_time: Optional[float] = None
+    # Where that moment ends, so it can be cut out as a clip. Null whenever start_time
+    # is, and for a moment whose transcript segment no longer exists.
+    end_time: Optional[float] = None
     segment_id: Optional[str] = None
     # Which retrievers found it — "keyword", "semantic", or both.
     sources: List[str] = Field(default_factory=list)
@@ -80,6 +83,7 @@ def search(
             score=round(fused.score, 6),
             snippet=fused.snippet,
             start_time=fused.start_time,
+            end_time=fused.end_time,
             segment_id=fused.segment_id,
             sources=sorted(fused.sources),
             other_matches=fused.other_matches,

backend/app/search/hybrid.py

@@ -62,6 +62,10 @@ class FusedAsset:
     # returns its single best moment is useful; one that floods the page with twenty of
     # its own moments is not.
     other_matches: int = 0
+    # Where the matched moment ends. Not carried through fusion: neither retriever has
+    # it to hand (the keyword index stores only the start), so it is looked up once for
+    # the final page — see `services/search.py::_attach_end_times`.
+    end_time: Optional[float] = None
 
 
 def fuse(ranked_lists: dict[str, Sequence[Candidate]], *, k: int = RRF_K) -> list[Candidate]:

backend/app/services/search.py

@@ -68,9 +68,34 @@ def search(
         allowed = _asset_ids_of_type(session, user_id, asset_type)
         fused = [a for a in fused if a.asset_id in allowed]
 
-    return SearchOutcome(
-        assets=fused[:limit], semantic_ran=semantic_ran, semantic_error=semantic_error
-    )
+    page = fused[:limit]
+    _attach_end_times(session, page)
+    return SearchOutcome(assets=page, semantic_ran=semantic_ran, semantic_error=semantic_error)
+
+
+def _attach_end_times(session: Session, hits: list[FusedAsset]) -> None:
+    """Give each moment its end, so a caller can cut it out without guessing a length.
+
+    Gecko Video Creator turns a hit into a clip ("where people talk about X"), and a
+    start alone leaves it to pick an out point blind. Looked up from the transcript
+    rather than stored in the FTS index: adding a column there means rebuilding the
+    whole index in a migration, for a value one indexed query fetches for a page of
+    thirty. Done after `limit`, so only hits that will be returned are looked up.
+    """
+    segment_ids = [h.segment_id for h in hits if h.segment_id]
+    if not segment_ids:
+        return
+    rows = session.exec(
+        select(TranscriptSegment.id, TranscriptSegment.end_time).where(
+            col(TranscriptSegment.id).in_(segment_ids)
+        )
+    ).all()
+    ends = dict(rows)
+    for hit in hits:
+        if hit.segment_id:
+            # A segment deleted since it was indexed (a transcript re-run) has no end to
+            # give; the hit keeps its start and says nothing rather than something wrong.
+            hit.end_time = ends.get(hit.segment_id)
 
 
 def _keyword_candidates(session: Session, user_id: str, query: str) -> list[Candidate]:

backend/tests/test_search_api.py

@@ -141,6 +141,28 @@ def test_a_spoken_hit_returns_the_second_it_was_said(embedded_library):
     assert "«nano»" in top["snippet"] or "«weapons»" in top["snippet"]
 
 
+def test_a_spoken_hit_says_where_the_moment_ends(embedded_library):
+    """So it can be cut out as a clip without guessing a length (Gecko Video Creator)."""
+    top = search(embedded_library["client"], "nano weapons")["data"][0]
+    assert (top["start_time"], top["end_time"]) == (412.0, 417.0)
+
+
+def test_a_moment_found_only_by_meaning_has_its_end_too(embedded_library):
+    """The semantic retriever reaches segments by a different path from the keyword
+    one; the end must not depend on which of them found the moment."""
+    # "armament" is said nowhere, so only the semantic half can find this moment.
+    top = search(embedded_library["client"], "armament")["data"][0]
+    assert top["asset"]["name"] == "Giordano interview"
+    assert top["sources"] == ["semantic"]
+    assert (top["start_time"], top["end_time"]) == (412.0, 417.0)
+
+
+def test_a_metadata_hit_has_no_moment_to_end(embedded_library):
+    top = search(embedded_library["client"], "committee")["data"][0]
+    assert top["start_time"] is None
+    assert top["end_time"] is None
+
+
 def test_the_snippet_is_the_line_not_the_whole_transcript(embedded_library):
     top = search(embedded_library["client"], "aerosol")["data"][0]
     assert len(top["snippet"]) < 200

docs/plan-of-attack.md

@@ -178,8 +178,10 @@ Two indexes over the same corpus, fused:
 - **Fusion**: Reciprocal Rank Fusion over the two ranked lists. No weights to tune, and
   exact-phrase queries and half-remembered ones both land.
 
-A result carries `{asset, score, snippet, start_time}`, and the UI deep-links to
-`/assets/{id}?t=412.0`.
+A result carries `{asset, score, snippet, start_time, end_time}`, and the UI deep-links
+to `/assets/{id}?t=412.0`. `end_time` is the matched transcript segment's end, so
+Gecko Video Creator can cut the moment out as a clip rather than guess its length
+(GVC's plan, GAM-1); it is looked up for the returned page, not stored in the index.
 
 ### Serving bytes — diverging from Notes on purpose
 

frontend/src/api/search.ts

@@ -10,6 +10,8 @@ export interface SearchHit {
   snippet: string
   /** Seconds into the asset. Null for a metadata hit, which is about the file itself. */
   start_time: number | null
+  /** Where that moment ends, for cutting it out as a clip. Null with `start_time`. */
+  end_time: number | null
   segment_id: string | null
   /** Which retrievers found it: 'keyword', 'semantic', or both. */
   sources: string[]

frontend/src/views/SearchView.test.tsx

@@ -44,6 +44,7 @@ function hit(overrides: Partial<SearchHit> = {}): SearchHit {
     score: 0.03,
     snippet: 'We are deploying «nano» «weapons» via aerosol dispersion.',
     start_time: 412,
+    end_time: 417,
     segment_id: 's1',
     sources: ['keyword', 'semantic'],
     other_matches: 0,