種子資材ベースへの切り替えを反映しました。

frontend/src/app/rice-transplant/_components/RiceTransplantEditPage.tsx では、田植え計画の主選択を 品種 から 種子資材 に変更し、画面上は種子資材名だけで進めるようにしました。保存時だけ内部的に、その種子資材に紐づく Variety を解決して既存 API に送っています。候補圃場取得もその内部参照で動く形です。frontend/src/app/rice-transplant/page.tsx の一覧表示も 作物 / 品種 ではなく 種子資材 列に変更しました。

仕様書 document/16_マスタードキュメント_田植え計画編.md も 年度 × 種子資材 を軸にした説明へ更新済みです。確認できたのは Python 側の py_compile までで、フロントのビルド確認はまだしていません。Issue #2 にも今回の変更内容をコメント済みです。

frontend/src/app/rice-transplant/_components/RiceTransplantEditPage.tsx

@@ -18,7 +18,7 @@ export default function RiceTransplantEditPage({ planId }: { planId?: number })
 
   const [name, setName] = useState('');
   const [year, setYear] = useState(currentYear);
-  const [varietyId, setVarietyId] = useState<number | ''>('');
+  const [seedMaterialId, setSeedMaterialId] = useState<number | ''>('');
   const [seedlingBoxesPerTan, setSeedlingBoxesPerTan] = useState('');
   const [defaultSeedGramsPerBox, setDefaultSeedGramsPerBox] = useState('200');
   const [notes, setNotes] = useState('');
@@ -39,8 +39,9 @@ export default function RiceTransplantEditPage({ planId }: { planId?: number })
 
   const years = Array.from({ length: 5 }, (_, i) => currentYear + 1 - i);
 
-  const getVariety = (id: number) =>
-    crops.flatMap((crop) => crop.varieties).find((variety) => variety.id === id);
+  const allVarieties = crops.flatMap((crop) => crop.varieties);
+  const getVarietyBySeedMaterial = (id: number) =>
+    allVarieties.find((variety) => variety.seed_material === id) ?? null;
 
   const calculateDefaultBoxes = (field: Field, perTan: string) => {
     const areaTan = parseFloat(field.area_tan || '0');
@@ -64,9 +65,12 @@ export default function RiceTransplantEditPage({ planId }: { planId?: number })
         if (!isNew && planId) {
           const planRes = await api.get(`/plans/rice-transplant-plans/${planId}/`);
           const plan: RiceTransplantPlan = planRes.data;
+          const fetchedVarieties = cropsRes.data.flatMap((crop: Crop) => crop.varieties);
+          const linkedVariety =
+            fetchedVarieties.find((variety) => variety.id === plan.variety) ?? null;
           setName(plan.name);
           setYear(plan.year);
-          setVarietyId(plan.variety);
+          setSeedMaterialId(linkedVariety?.seed_material ?? '');
           setSeedlingBoxesPerTan(plan.seedling_boxes_per_tan);
           setDefaultSeedGramsPerBox(plan.default_seed_grams_per_box);
           setNotes(plan.notes);
@@ -97,10 +101,11 @@ export default function RiceTransplantEditPage({ planId }: { planId?: number })
 
   useEffect(() => {
     const fetchCandidates = async () => {
-      if (!varietyId || !year || (!isNew && loading)) return;
+      const selectedVariety = seedMaterialId ? getVarietyBySeedMaterial(seedMaterialId) : null;
+      if (!selectedVariety || !year || (!isNew && loading)) return;
       try {
         const res = await api.get(
-          `/plans/rice-transplant-plans/candidate_fields/?year=${year}&variety_id=${varietyId}`
+          `/plans/rice-transplant-plans/candidate_fields/?year=${year}&variety_id=${selectedVariety.id}`
         );
         const nextCandidates: Field[] = res.data;
         setCandidateFields(nextCandidates);
@@ -113,16 +118,16 @@ export default function RiceTransplantEditPage({ planId }: { planId?: number })
       }
     };
     fetchCandidates();
-  }, [varietyId, year, isNew, loading]);
+  }, [seedMaterialId, year, isNew, loading]);
 
   useEffect(() => {
-    if (!varietyId) return;
-    const variety = getVariety(varietyId);
+    if (!seedMaterialId) return;
+    const variety = getVarietyBySeedMaterial(seedMaterialId);
     if (!variety) return;
     if (isNew || seedlingBoxesPerTan === '') {
       setSeedlingBoxesPerTan(variety.default_seedling_boxes_per_tan);
     }
-  }, [varietyId, crops, isNew, seedlingBoxesPerTan]);
+  }, [seedMaterialId, crops, isNew, seedlingBoxesPerTan]);
 
   useEffect(() => {
     const nextCalc: BoxMap = {};
@@ -206,15 +211,15 @@ export default function RiceTransplantEditPage({ planId }: { planId?: number })
     return Number.isNaN(value) ? 0 : value;
   };
 
-  const selectedVariety = varietyId ? getVariety(varietyId) : null;
-  const seedStock = selectedVariety?.seed_material
-    ? seedStocks.find((item) => item.material_id === selectedVariety.seed_material) ?? null
+  const selectedSeedStock = seedMaterialId
+    ? seedStocks.find((item) => item.material_id === seedMaterialId) ?? null
     : null;
+  const selectedVariety = seedMaterialId ? getVarietyBySeedMaterial(seedMaterialId) : null;
 
   const totalBoxes = selectedFields.reduce((sum, field) => sum + effectiveBoxes(field.id), 0);
   const seedGrams = parseFloat(defaultSeedGramsPerBox || '0');
   const totalSeedKg = seedGrams > 0 ? (totalBoxes * seedGrams) / 1000 : 0;
-  const seedInventoryKg = parseFloat(seedStock?.current_stock ?? '0');
+  const seedInventoryKg = parseFloat(selectedSeedStock?.current_stock ?? '0');
   const remainingSeedKg = seedInventoryKg - totalSeedKg;
 
   const handleSave = async () => {
@@ -223,8 +228,12 @@ export default function RiceTransplantEditPage({ planId }: { planId?: number })
       setError('計画名を入力してください。');
       return;
     }
-    if (!varietyId) {
-      setError('品種を選択してください。');
+    if (!seedMaterialId) {
+      setError('種子資材を選択してください。');
+      return;
+    }
+    if (!selectedVariety) {
+      setError('選択した種子資材に対応する品種が未設定です。資材マスタで紐付けてください。');
       return;
     }
     if (selectedFields.length === 0) {
@@ -240,7 +249,7 @@ export default function RiceTransplantEditPage({ planId }: { planId?: number })
     const payload = {
       name,
       year,
-      variety: varietyId,
+      variety: selectedVariety.id,
       seedling_boxes_per_tan: seedlingBoxesPerTan || '0',
       default_seed_grams_per_box: defaultSeedGramsPerBox || '0',
       notes,
@@ -349,21 +358,19 @@ export default function RiceTransplantEditPage({ planId }: { planId?: number })
             </select>
           </div>
           <div>
-            <label className="mb-1 block text-xs font-medium text-gray-600">品種</label>
+            <label className="mb-1 block text-xs font-medium text-gray-600">種子資材</label>
             <select
-              value={varietyId}
-              onChange={(e) => setVarietyId(e.target.value ? parseInt(e.target.value, 10) : '')}
+              value={seedMaterialId}
+              onChange={(e) =>
+                setSeedMaterialId(e.target.value ? parseInt(e.target.value, 10) : '')
+              }
               className="w-full rounded-lg border border-gray-300 px-3 py-2 text-sm focus:outline-none focus:ring-2 focus:ring-green-500"
             >
               <option value="">選択してください</option>
-              {crops.map((crop) => (
-                <optgroup key={crop.id} label={crop.name}>
-                  {crop.varieties.map((variety) => (
-                    <option key={variety.id} value={variety.id}>
-                      {variety.name}
-                    </option>
-                  ))}
-                </optgroup>
+              {seedStocks.map((stock) => (
+                <option key={stock.material_id} value={stock.material_id}>
+                  {stock.name}
+                </option>
               ))}
             </select>
           </div>
@@ -445,7 +452,7 @@ export default function RiceTransplantEditPage({ planId }: { planId?: number })
                 <span>{totalSeedKg.toFixed(3)}kg</span>
               </div>
               <div className="flex justify-between text-gray-600">
-                <span>{seedStock?.name || selectedVariety?.seed_material_name || '種子在庫未設定'}</span>
+                <span>{selectedSeedStock?.name || '種子在庫未設定'}</span>
                 <span>{seedInventoryKg.toFixed(3)}kg</span>
               </div>
               <div