Add number of games filter to purchases

common/components/filters.py

@@ -847,6 +847,16 @@ def PurchaseFilterBar(
     except Exception:
         price_range_min, price_range_max = 0, 100
 
+    num_min, num_max = _parse_range(existing, "num_purchases")
+    try:
+        num_aggregate = Purchase.objects.aggregate(
+            num_min=models.Min("num_purchases"), num_max=models.Max("num_purchases")
+        )
+        num_range_min = max(int(num_aggregate.get("num_min") or 0), 0)
+        num_range_max = max(int(num_aggregate.get("num_max") or 10), 1)
+    except Exception:
+        num_range_min, num_range_max = 0, 10
+
     fields = [
         Component(
             tag_name="div",
@@ -912,5 +922,16 @@ def PurchaseFilterBar(
             min_placeholder="0.00",
             max_placeholder="100.00",
         ),
+        RangeSlider(
+            label="Games in purchase",
+            input_name_prefix="filter-num-purchases",
+            min_value=num_min,
+            max_value=num_max,
+            range_min=num_range_min,
+            range_max=num_range_max,
+            step="1",
+            min_placeholder="e.g. 1",
+            max_placeholder="e.g. 5",
+        ),
     ]
     return _filter_bar(fields, filter_json, preset_list_url, preset_save_url)

games/static/js/filter_bar.js

@@ -130,6 +130,17 @@
       }
     }
 
+    // ── Purchase-specific: num_purchases ──
+    var numGamesMin = numberValue(form, "filter-num-purchases-min");
+    var numGamesMax = numberValue(form, "filter-num-purchases-max");
+    if (numGamesMin !== "" && numGamesMax !== "") {
+      filter.num_purchases = criterion(parseInt(numGamesMin, 10), parseInt(numGamesMax, 10), "BETWEEN");
+    } else if (numGamesMin !== "") {
+      filter.num_purchases = criterion(parseInt(numGamesMin, 10), null, "GREATER_THAN");
+    } else if (numGamesMax !== "") {
+      filter.num_purchases = criterion(parseInt(numGamesMax, 10), null, "LESS_THAN");
+    }
+
     if (mastered && mastered.checked) {
       filter.mastered = criterion(true, null, "EQUALS");
     }

tests/test_filters.py

@@ -563,3 +563,70 @@ class TestFilterBarRendering:
         platform_section = html[platform_start:]
         # Should have at least one modifier option
         assert "(Any)" in platform_section or "(None)" in platform_section
+
+
+class TestPurchaseNumPurchasesAgainstDB:
+    """num_purchases IntCriterion filters purchases by game count."""
+
+    def _seed(self):
+        import datetime
+
+        from games.models import Game, Platform, Purchase
+
+        platform, _ = Platform.objects.get_or_create(name="Test", icon="test")
+        a, _ = Game.objects.get_or_create(name="A", defaults={"platform": platform})
+        b, _ = Game.objects.get_or_create(name="B", defaults={"platform": platform})
+        c, _ = Game.objects.get_or_create(name="C", defaults={"platform": platform})
+
+        single = Purchase.objects.create(
+            platform=platform, date_purchased=datetime.date(2024, 1, 1)
+        )
+        single.games.set([a])
+
+        double = Purchase.objects.create(
+            platform=platform, date_purchased=datetime.date(2024, 1, 1)
+        )
+        double.games.set([a, b])
+
+        triple = Purchase.objects.create(
+            platform=platform, date_purchased=datetime.date(2024, 1, 1)
+        )
+        triple.games.set([a, b, c])
+
+        return {"single": single, "double": double, "triple": triple}
+
+    @pytest.mark.django_db
+    def test_between_two_and_three(self):
+        from games.filters import PurchaseFilter
+        from games.models import Purchase
+
+        seeded = self._seed()
+        pf = PurchaseFilter.from_json(
+            {"num_purchases": {"value": 2, "value2": 3, "modifier": "BETWEEN"}}
+        )
+        result = set(Purchase.objects.filter(pf.to_q()))
+        assert result == {seeded["double"], seeded["triple"]}
+
+    @pytest.mark.django_db
+    def test_greater_than_one(self):
+        from games.filters import PurchaseFilter
+        from games.models import Purchase
+
+        seeded = self._seed()
+        pf = PurchaseFilter.from_json(
+            {"num_purchases": {"value": 1, "modifier": "GREATER_THAN"}}
+        )
+        result = set(Purchase.objects.filter(pf.to_q()))
+        assert result == {seeded["double"], seeded["triple"]}
+
+    @pytest.mark.django_db
+    def test_equals_one(self):
+        from games.filters import PurchaseFilter
+        from games.models import Purchase
+
+        seeded = self._seed()
+        pf = PurchaseFilter.from_json(
+            {"num_purchases": {"value": 1, "modifier": "EQUALS"}}
+        )
+        result = set(Purchase.objects.filter(pf.to_q()))
+        assert result == {seeded["single"]}