Move unspread fertilization entries on variety change

backend/apps/fertilizer/services.py

@@ -3,9 +3,10 @@ from decimal import Decimal
 from django.db import transaction
 from django.db.models import Sum
 
+from apps.materials.stock_service import create_reserves_for_plan
 from apps.materials.models import StockTransaction
 from apps.workrecords.services import sync_spreading_work_record
-from .models import FertilizationEntry, SpreadingSessionItem
+from .models import FertilizationEntry, FertilizationPlan, SpreadingSessionItem
 
 
 def sync_actual_bags_for_pairs(year, field_fertilizer_pairs):
@@ -56,3 +57,51 @@ def sync_stock_uses_for_spreading_session(session):
             fertilization_plan=None,
             spreading_item=item,
         )
+
+
+@transaction.atomic
+def move_unspread_entries_for_variety_change(change):
+    moved_count = 0
+    old_variety_id = change.old_variety_id
+    new_variety = change.new_variety
+    if old_variety_id is None or new_variety is None:
+        return 0
+
+    old_plans = (
+        FertilizationPlan.objects
+        .filter(
+            year=change.year,
+            variety_id=old_variety_id,
+            entries__field_id=change.field_id,
+            entries__actual_bags__isnull=True,
+        )
+        .distinct()
+        .prefetch_related('entries')
+    )
+
+    for old_plan in old_plans:
+        entries_to_move = list(
+            old_plan.entries.filter(
+                field_id=change.field_id,
+                actual_bags__isnull=True,
+            ).order_by('id')
+        )
+        if not entries_to_move:
+            continue
+
+        new_plan = FertilizationPlan.objects.create(
+            name=f'{change.year}年度 {new_variety.name} 施肥計画（品種変更移動）',
+            year=change.year,
+            variety=new_variety,
+            calc_settings=old_plan.calc_settings,
+        )
+
+        FertilizationEntry.objects.filter(
+            id__in=[entry.id for entry in entries_to_move]
+        ).update(plan=new_plan)
+
+        create_reserves_for_plan(old_plan)
+        create_reserves_for_plan(new_plan)
+        moved_count += len(entries_to_move)
+
+    return moved_count

backend/apps/plans/services.py

@@ -59,7 +59,12 @@ def handle_plan_variety_change(plan: Plan, *, old_variety, new_variety, reason:
 
 
 def process_plan_variety_change(change: PlanVarietyChange):
-    """後続 issue で施肥計画・田植え計画への移動処理を追加する入口。"""
+    from apps.fertilizer.services import move_unspread_entries_for_variety_change
+
+    moved_count = move_unspread_entries_for_variety_change(change)
+    if moved_count != change.moved_entry_count:
+        change.moved_entry_count = moved_count
+        change.save(update_fields=['moved_entry_count'])
     return change
 
 

backend/apps/plans/tests.py

@@ -2,7 +2,10 @@ from django.contrib.auth import get_user_model
 from django.test import TestCase
 from rest_framework.test import APIRequestFactory, force_authenticate
 
+from apps.fertilizer.models import FertilizationEntry, FertilizationPlan, Fertilizer
 from apps.fields.models import Field
+from apps.materials.models import Material, StockTransaction
+from apps.materials.stock_service import create_reserves_for_plan
 from .models import Crop, Plan, PlanVarietyChange, Variety
 from .serializers import PlanSerializer
 from .views import PlanViewSet
@@ -34,6 +37,15 @@ class PlanVarietyChangeTests(TestCase):
             variety=self.old_variety,
             notes='',
         )
+        self.other_field = Field.objects.create(
+            name='足川南',
+            address='高知県高岡郡',
+            area_tan='0.8000',
+            area_m2=800,
+            owner_name='吉田',
+            group_name='南',
+            display_order=2,
+        )
 
     def test_serializer_update_creates_history_when_variety_changes(self):
         serializer = PlanSerializer(
@@ -90,3 +102,102 @@ class PlanVarietyChangeTests(TestCase):
         change = PlanVarietyChange.objects.get(plan=self.plan)
         self.assertEqual(change.old_variety_id, self.old_variety.id)
         self.assertEqual(change.new_variety_id, self.new_variety.id)
+
+    def test_serializer_update_moves_only_unspread_fertilizer_entries(self):
+        material_unspread = Material.objects.create(
+            name='高度化成14号',
+            material_type=Material.MaterialType.FERTILIZER,
+        )
+        material_partial = Material.objects.create(
+            name='分げつ一発',
+            material_type=Material.MaterialType.FERTILIZER,
+        )
+        fertilizer_unspread = Fertilizer.objects.create(
+            name='高度化成14号',
+            material=material_unspread,
+        )
+        fertilizer_partial = Fertilizer.objects.create(
+            name='分げつ一発',
+            material=material_partial,
+        )
+        old_fertilization_plan = FertilizationPlan.objects.create(
+            name='2026年度 にこまる 元肥',
+            year=2026,
+            variety=self.old_variety,
+            calc_settings=[{'fertilizer_id': fertilizer_unspread.id, 'method': 'per_tan', 'param': '1.0'}],
+        )
+        unspread_entry = FertilizationEntry.objects.create(
+            plan=old_fertilization_plan,
+            field=self.field,
+            fertilizer=fertilizer_unspread,
+            bags='4.00',
+            actual_bags=None,
+        )
+        partial_entry = FertilizationEntry.objects.create(
+            plan=old_fertilization_plan,
+            field=self.field,
+            fertilizer=fertilizer_partial,
+            bags='3.00',
+            actual_bags='1.0000',
+        )
+        untouched_entry = FertilizationEntry.objects.create(
+            plan=old_fertilization_plan,
+            field=self.other_field,
+            fertilizer=fertilizer_unspread,
+            bags='2.00',
+            actual_bags=None,
+        )
+        create_reserves_for_plan(old_fertilization_plan)
+
+        serializer = PlanSerializer(
+            instance=self.plan,
+            data={'variety': self.new_variety.id},
+            partial=True,
+        )
+        self.assertTrue(serializer.is_valid(), serializer.errors)
+        serializer.save()
+
+        change = PlanVarietyChange.objects.get(plan=self.plan)
+        self.assertEqual(change.moved_entry_count, 1)
+
+        old_fertilization_plan.refresh_from_db()
+        new_plan = FertilizationPlan.objects.exclude(id=old_fertilization_plan.id).get(
+            year=2026,
+            variety=self.new_variety,
+        )
+        self.assertEqual(
+            new_plan.name,
+            f'2026年度 {self.new_variety.name} 施肥計画（品種変更移動）',
+        )
+        self.assertEqual(new_plan.calc_settings, old_fertilization_plan.calc_settings)
+
+        unspread_entry.refresh_from_db()
+        partial_entry.refresh_from_db()
+        untouched_entry.refresh_from_db()
+
+        self.assertEqual(unspread_entry.plan_id, new_plan.id)
+        self.assertEqual(partial_entry.plan_id, old_fertilization_plan.id)
+        self.assertEqual(untouched_entry.plan_id, old_fertilization_plan.id)
+
+        old_reserves = list(
+            StockTransaction.objects.filter(
+                fertilization_plan=old_fertilization_plan,
+                transaction_type=StockTransaction.TransactionType.RESERVE,
+            ).order_by('material__name')
+        )
+        new_reserves = list(
+            StockTransaction.objects.filter(
+                fertilization_plan=new_plan,
+                transaction_type=StockTransaction.TransactionType.RESERVE,
+            ).order_by('material__name')
+        )
+        self.assertEqual(len(old_reserves), 2)
+        self.assertEqual(len(new_reserves), 1)
+        self.assertEqual(
+            {(reserve.material_id, reserve.quantity) for reserve in old_reserves},
+            {
+                (material_partial.id, partial_entry.bags),
+                (material_unspread.id, untouched_entry.bags),
+            },
+        )
+        self.assertEqual(new_reserves[0].quantity, unspread_entry.bags)