feat(purchase): 一次性直购计费 storage_direct_charging(选A购买即记账)

存储买断模式：不依赖采样，按购买容量×月数直接计费出账。
- storage_direct_charging(spec, storage_gb, valid_months)：package定价×月数
- calculate_product_cost 支持 direct 模式复用 package 定价 + 月数乘法
- 注册 env.storage_direct_charging + __init__ 导出

storage_resource/__init__.py

@@ -5,6 +5,7 @@ from .init import (
     get_storage_ppid,
     record_storage_sample,
     storage_charging,
+    storage_direct_charging,
     resolve_ppid,
 )
 

storage_resource/init.py

@@ -312,6 +312,95 @@ async def storage_charging(spec_id_or_code, meter_mode, userid, userorgid,
     return rec
 
 
+async def storage_direct_charging(spec_id_or_code, storage_gb, userid, userorgid,
+                                  valid_months=1, subscription_id='', discount_rate=None):
+    """一次性直购计费（购买即记账，选 A 模式）：不依赖采样，按购买容量 × 有效期出账。
+
+    定价单位 GB月：买 N 个月容量 = storage_gb × valid_months 个 GB月。
+    usages 里 sample_count=0 标记直购（区别于采样出账），计费因子 = storage_gb。
+    """
+    storage_gb = float(storage_gb or 0)
+    if storage_gb <= 0:
+        raise Exception('购买容量必须大于 0')
+    valid_months = max(1, int(valid_months or 1))
+
+    spec = await get_storage_spec(spec_id_or_code)
+    if not spec:
+        raise Exception('存储规格不存在: %s' % spec_id_or_code)
+    spec_id = _val(spec, 'id')
+    min_gb = float(_val(spec, 'min_gb') or 0)
+    if min_gb and storage_gb < min_gb:
+        raise Exception('购买容量不能低于最小规格 %sGB' % min_gb)
+
+    # 直购按 package（包月）定价解析；无 package 则取缺省映射
+    ppid = await get_storage_ppid(spec_id_or_code, 'package') \
+        or await get_storage_ppid(spec_id_or_code)
+    usages = {
+        'storage_gb': storage_gb,
+        'valid_months': valid_months,
+        'sample_count': 0,
+        'meter_mode': 'direct',
+        'purchase': True,
+    }
+
+    env = ServerEnv()
+    amount = 0.0
+    if ppid:
+        charging = getattr(env, 'buffered_charging', None)
+        if charging is None:
+            logger.warning('pricing 模块未加载，直购计费金额记 0（ppid=%s）', ppid)
+        else:
+            try:
+                prices = await charging(ppid, usages)
+                if prices is None:
+                    logger.error('直购定价计算返回空 ppid=%s', ppid)
+                else:
+                    amount = float(sum(getattr(p, 'amount', 0) or 0 for p in prices))
+                    # 多个月：单价按 GB月，购买 N 个月按 N 倍计
+                    if valid_months > 1:
+                        amount = amount * valid_months
+            except Exception as e:
+                logger.error('直购计费失败 ppid=%s: %s', ppid, e)
+                raise Exception('计费失败: %s' % e)
+    else:
+        raise Exception('存储无定价方案，无法购买（缺 storres_pricing_map 映射）')
+
+    rate = float(discount_rate) if discount_rate not in (None, '') else 1.0
+    final_amount = round(amount * rate, 4)
+
+    today = datetime.date.today()
+    end = today + datetime.timedelta(days=30 * valid_months)
+    rec = {
+        'id': getID(),
+        'spec_id': spec_id,
+        'meter_mode': 'direct',
+        'subscription_id': subscription_id,
+        'userid': userid,
+        'userorgid': userorgid,
+        'use_date': _today(),
+        'use_time': _now(),
+        'period_start': today.strftime('%Y-%m-%d'),
+        'period_end': end.strftime('%Y-%m-%d'),
+        'sample_count': 0,
+        'avg_gb': storage_gb,
+        'max_gb': storage_gb,
+        'billable_gb': storage_gb,
+        'usages': json.dumps(usages, ensure_ascii=False),
+        'transno': getID(),
+        'amount': final_amount,
+        'discount_rate': rate,
+        'accounting_status': 'pending',
+        'status': 'active',
+        'org_id': userorgid,
+        'created_at': _now(),
+    }
+    async with DBPools().sqlorContext(_get_dbname()) as sor:
+        await sor.C('storres_usage', rec)
+    logger.info('存储直购: spec=%s 容量=%sGB 有效=%s月 原价=%s 折扣=%s 应收=%s',
+                spec_id_or_code, storage_gb, valid_months, amount, rate, final_amount)
+    return rec
+
+
 async def get_accounting_storres_usages(limit=200):
     async with DBPools().sqlorContext(_get_dbname()) as sor:
         return await sor.sqlExe(
@@ -349,6 +438,7 @@ def load_storage_resource():
     env.record_storage_sample = record_storage_sample
     env.summarize_samples = summarize_samples
     env.storage_charging = storage_charging
+    env.storage_direct_charging = storage_direct_charging
     env.get_accounting_storres_usages = get_accounting_storres_usages
     env.mark_storres_accounted = mark_storres_accounted
 

storage_resource/product_interface.py

@@ -141,7 +141,9 @@ async def calculate_product_cost(resource_ref_id, usage_data, user_org_id=None):
 
     usage_data = usage_data or {}
     meter_mode = usage_data.get('meter_mode', 'ondemand')
-    ppid = await get_storage_ppid(getattr(spec, 'id'), meter_mode)
+    # direct(直购) 复用 package 定价（买断=包月价×月数）
+    ppid_mode = 'package' if meter_mode == 'direct' else meter_mode
+    ppid = await get_storage_ppid(getattr(spec, 'id'), ppid_mode)
     if not ppid:
         return {'success': False, 'message': '无定价方案(ppid为空)'}
 
@@ -154,6 +156,10 @@ async def calculate_product_cost(resource_ref_id, usage_data, user_org_id=None):
         return {'success': False, 'message': '定价计算失败: %s' % e}
 
     amount = sum(getattr(p, 'amount', 0) for p in prices)
+    # 直购多个月：单价按 GB月，购买 N 个月按 N 倍计（与 storage_direct_charging 一致）
+    valid_months = int(usage_data.get('valid_months', 1) or 1)
+    if meter_mode == 'direct' and valid_months > 1:
+        amount = amount * valid_months
 
     # 资源层只算真实定价（原价）。产品级折扣（客户/分销商/供应商）由产品层
     # calculate_product_cost 按 product_id 精确计算，见 product_management.core。