feat: manual match pin/unpin endpoints

backend/app/api/ingredients.py

@@ -1,16 +1,23 @@
 from __future__ import annotations
 
+from decimal import Decimal
 from typing import List, Optional
 from uuid import UUID
 
 from fastapi import APIRouter, Depends, HTTPException, Query, Response, status
+from pydantic import BaseModel
 from sqlalchemy import or_
 from sqlalchemy.exc import IntegrityError
 from sqlalchemy.orm import Session
 
 from app.database import get_db
-from app.models import Ingredient
-from app.schemas.ingredient import IngredientCreate, IngredientRead, IngredientUpdate
+from app.models import Ingredient, IngredientGroceryMatch, IngredientMatchSource
+from app.schemas.ingredient import (
+    IngredientCreate,
+    IngredientGroceryMatchRead,
+    IngredientRead,
+    IngredientUpdate,
+)
 from app.security import require_admin
 
 
@@ -105,3 +112,65 @@ def delete_ingredient(ingredient_id: UUID, db: Session = Depends(get_db)):
     db.delete(row)
     db.commit()
     return Response(status_code=status.HTTP_204_NO_CONTENT)
+
+
+class _PinMatchBody(BaseModel):
+    grocery_item_id: UUID
+    confidence: float = 1.0
+
+
+@admin_router.post(
+    "/{ingredient_id}/matches",
+    response_model=IngredientGroceryMatchRead,
+    status_code=status.HTTP_201_CREATED,
+)
+def pin_match(
+    ingredient_id: UUID,
+    payload: _PinMatchBody,
+    db: Session = Depends(get_db),
+):
+    existing = (
+        db.query(IngredientGroceryMatch)
+        .filter(
+            IngredientGroceryMatch.ingredient_id == ingredient_id,
+            IngredientGroceryMatch.grocery_item_id == payload.grocery_item_id,
+        )
+        .first()
+    )
+    if existing:
+        existing.source = IngredientMatchSource.MANUAL
+        existing.confidence = Decimal(str(round(payload.confidence, 3)))
+        db.commit()
+        db.refresh(existing)
+        return existing
+    row = IngredientGroceryMatch(
+        ingredient_id=ingredient_id,
+        grocery_item_id=payload.grocery_item_id,
+        confidence=Decimal(str(round(payload.confidence, 3))),
+        source=IngredientMatchSource.MANUAL,
+    )
+    db.add(row)
+    db.commit()
+    db.refresh(row)
+    return row
+
+
+_match_admin_router = APIRouter(
+    prefix="/api/admin/ingredient-matches",
+    tags=["ingredients-admin"],
+    dependencies=[Depends(require_admin)],
+)
+
+
+@_match_admin_router.delete(
+    "/{match_id}",
+    status_code=status.HTTP_204_NO_CONTENT,
+    response_class=Response,
+)
+def unpin_match(match_id: UUID, db: Session = Depends(get_db)) -> Response:
+    row = db.query(IngredientGroceryMatch).filter(IngredientGroceryMatch.id == match_id).first()
+    if row is None:
+        raise HTTPException(status_code=404, detail="match not found")
+    db.delete(row)
+    db.commit()
+    return Response(status_code=status.HTTP_204_NO_CONTENT)

backend/app/main.py

@@ -41,5 +41,6 @@ app.include_router(pantry.router, prefix="/api/pantry", tags=["pantry"])
 app.include_router(admin.router, prefix="/api/admin", tags=["admin"])
 app.include_router(ingredients_api.public_router)
 app.include_router(ingredients_api.admin_router)
+app.include_router(ingredients_api._match_admin_router)
 app.include_router(recipes_api.public_router)
 app.include_router(recipes_api.admin_router)

backend/tests/conftest.py

@@ -155,6 +155,19 @@ def db(_engine):
         connection.close()
 
 
+@pytest.fixture()
+def db_session():
+    """Plain SessionLocal for tests that need to seed data outside the
+    transactional ``db`` fixture (e.g. setting up rows the API will read)."""
+    from app.database import SessionLocal
+
+    s = SessionLocal()
+    try:
+        yield s
+    finally:
+        s.close()
+
+
 @pytest.fixture()
 def client(db):
     """TestClient with get_db overridden to yield the test session."""

backend/tests/test_ingredient_api.py

@@ -63,6 +63,68 @@ def test_update_ingredient_replaces_aliases(client):
     assert r.json()["aliases"] == ["yellow onion", "spanish onion"]
 
 
+def _seed_grocery(db_session, name: str) -> str:
+    from datetime import datetime, timezone
+    from decimal import Decimal
+    from uuid import uuid4
+
+    from app.models import GroceryItem
+
+    gid = uuid4()
+    db_session.add(
+        GroceryItem(
+            id=gid,
+            name=name,
+            source="lucky_california",
+            external_id=f"ext-{gid}",
+            current_price=Decimal("4.99"),
+            regular_price=Decimal("4.99"),
+            is_on_sale=False,
+            scraped_at=datetime.now(timezone.utc),
+        )
+    )
+    db_session.commit()
+    return str(gid)
+
+
+def test_pin_manual_match(client, db_session):
+    create = client.post(
+        "/api/admin/ingredients",
+        json={"name": "Test Manual Pin Veggie", "aliases": [], "aisle": "produce", "unit": "ea"},
+        headers=_admin_headers(),
+    )
+    iid = create.json()["id"]
+    gid = _seed_grocery(db_session, "Some Other Veggie Brand Test")
+
+    r = client.post(
+        f"/api/admin/ingredients/{iid}/matches",
+        json={"grocery_item_id": gid, "confidence": 1.0},
+        headers=_admin_headers(),
+    )
+    assert r.status_code == 201, r.text
+    body = r.json()
+    assert body["source"] == "manual"
+    assert body["grocery_item_id"] == gid
+
+
+def test_unpin_manual_match(client, db_session):
+    create = client.post(
+        "/api/admin/ingredients",
+        json={"name": "Test Unpin Test Item", "aliases": [], "aisle": "produce", "unit": "ea"},
+        headers=_admin_headers(),
+    )
+    iid = create.json()["id"]
+    gid = _seed_grocery(db_session, "Brand X Test Product")
+    pin = client.post(
+        f"/api/admin/ingredients/{iid}/matches",
+        json={"grocery_item_id": gid, "confidence": 1.0},
+        headers=_admin_headers(),
+    )
+    match_id = pin.json()["id"]
+    r = client.delete(f"/api/admin/ingredient-matches/{match_id}", headers=_admin_headers())
+    assert r.status_code == 204
+
+
 def test_delete_ingredient_removes_row(client):
     create = client.post(
         "/api/admin/ingredients",