# IMPLEMENTATION_PLAN：积分流水列表功能

## 概述

本计划按 trellis 工作流制定，遵循 `schema → repository → service → router` 后端分层和 `data → presentation` 前端分层原则。

## 前置条件确认

| 条件 | 状态 | 说明 |
|------|------|------|
| `points_ledger` 表存在 | ✅ | 结构完整，有索引支持分页 |
| Repository 写入方法存在 | ✅ | `append_ledger()` 已实现 |
| 积分中心页面存在 | ✅ | `CoinCenterScreen` 可添加入口 |
| 前端 points feature 存在 | ✅ | `features/points/` 目录已存在 |

## 实现步骤

### Step 1: 后端 Schema 定义

**文件**：`backend/src/v1/points/schemas.py`

**新增内容**：
```python
class LedgerItem(BaseModel):
    model_config = ConfigDict(populate_by_name=True, serialize_by_alias=True)

    id: str
    direction: int  # 1=收入, -1=支出
    amount: int = Field(ge=1)
    balance_after: int = Field(alias="balanceAfter", ge=0)
    change_type: str = Field(alias="changeType")
    display_text: str = Field(alias="displayText")
    created_at: str = Field(alias="createdAt")


class LedgerListResponse(BaseModel):
    model_config = ConfigDict(populate_by_name=True, serialize_by_alias=True)

    items: list[LedgerItem]
    next_cursor: str | None = Field(alias="nextCursor", default=None)
    has_more: bool = Field(alias="hasMore")
```

### Step 2: 后端 Repository 方法

**文件**：`backend/src/v1/points/repository.py`

**新增方法**：
```python
async def list_ledger(
    self,
    *,
    user_id: UUID,
    limit: int,
    cursor: datetime | None = None,
) -> tuple[list[PointsLedger], bool]:
    # 按 created_at DESC 分页查询
    # cursor 为上一页最后一条的 created_at
    # 多查一条判断 has_more
```

### Step 3: 后端 Service 方法

**文件**：`backend/src/v1/points/service.py`

**新增方法**：
```python
async def get_ledger_list(
    self,
    *,
    user_id: UUID,
    limit: int = 20,
    cursor: str | None = None,
) -> tuple[list[LedgerItem], str | None, bool]:
    # 1. 解析 cursor 为 datetime
    # 2. 调用 repository.list_ledger()
    # 3. 组装 display_text（根据 change_type）
    # 4. 返回 (items, next_cursor, has_more)
```

**display_text 映射**：
```python
CHANGE_TYPE_TEXT = {
    "register": ("注册赠送", "Registration bonus"),
    "purchase": ("购买积分包", "Purchase credits"),
    "consume": ("AI 对话消耗", "AI chat cost"),
    "adjust": ("系统调整", "System adjustment"),
    "refund": ("退款", "Refund"),
}
```

### Step 4: 后端 Router 端点

**文件**：`backend/src/v1/points/router.py`

**新增端点**：
```python
@router.get("/ledger", response_model=LedgerListResponse)
async def get_points_ledger(
    service: Annotated[PointsService, Depends(get_points_service)],
    current_user: Annotated[CurrentUser, Depends(get_current_user)],
    limit: int = Query(default=20, ge=1, le=100),
    cursor: str | None = Query(default=None),
) -> LedgerListResponse:
    ...
```

### Step 5: 前端 Model 定义

**文件**：`apps/lib/features/points/data/models/ledger_item.dart`

```dart
class LedgerItem {
  const LedgerItem({
    required this.id,
    required this.direction,
    required this.amount,
    required this.balanceAfter,
    required this.changeType,
    required this.displayText,
    required this.createdAt,
  });

  final String id;
  final int direction; // 1=收入, -1=支出
  final int amount;
  final int balanceAfter;
  final String changeType;
  final String displayText;
  final String createdAt;

  factory LedgerItem.fromJson(Map<String, dynamic> json) => ...;
}

class LedgerListResult {
  const LedgerListResult({
    required this.items,
    this.nextCursor,
    required this.hasMore,
  });

  final List<LedgerItem> items;
  final String? nextCursor;
  final bool hasMore;
}
```

### Step 6: 前端 API 方法

**文件**：`apps/lib/features/points/data/apis/points_api.dart`

**新增方法**：
```dart
Future<LedgerListResult> getLedger({
  int limit = 20,
  String? cursor,
}) async {
  final query = {'limit': limit};
  if (cursor != null) query['cursor'] = cursor;
  final response = await _dio.get('/api/v1/points/ledger', queryParameters: query);
  return LedgerListResult.fromJson(response.data);
}
```

### Step 7: 前端流水列表页面

**文件**：`apps/lib/features/points/presentation/screens/points_ledger_screen.dart`

**功能**：
- 标题：积分流水
- 列表项：类型图标 + 文案 + 金额（颜色区分） + 时间
- 分页加载：滚动到底部加载更多
- 空状态：暂无流水记录
- Loading 状态

### Step 8: 重命名 AccountDeleteScreen 为 AccountDataScreen

**文件操作**：
1. 重命名文件：`account_delete_screen.dart` → `account_data_screen.dart`
2. 重命名类：`AccountDeleteScreen` → `AccountDataScreen`
3. 更新类内状态名：`_AccountDeleteScreenState` → `_AccountDataScreenState`

**页面结构变更**：
```dart
// 之前：只有删除账号入口
body: ListView(
  children: [
    SettingsGroupCard(
      children: [
        SettingsMenuTile(icon: Icons.delete_outline_rounded, ...),
      ],
    ),
  ],
),

// 之后：积分流水 + 删除账号
body: ListView(
  children: [
    SettingsGroupCard(
      children: [
        SettingsMenuTile(
          icon: Icons.receipt_long_rounded,
          title: l10n.pointsLedgerTitle,  // 积分流水
          tint: colors.primary,
          background: colors.surfaceContainerHighest,
          onTap: _openPointsLedger,
        ),
        SettingsMenuTile(
          icon: Icons.delete_outline_rounded,
          title: l10n.settingsDeleteAccountTitle,
          tint: colors.error,
          background: colors.surfaceContainerHighest,
          titleColor: colors.error,
          showDivider: false,
          onTap: _confirmDelete,
        ),
      ],
    ),
  ],
),
```

**新增方法**：
```dart
Future<void> _openPointsLedger() async {
  await Navigator.of(context).push<void>(
    MaterialPageRoute<void>(
      builder: (_) => PointsLedgerScreen(
        apiClient: widget.apiClient,
        userId: widget.userId,
      ),
    ),
  );
}
```

**新增 widget 参数**：
```dart
class AccountDataScreen extends StatefulWidget {
  const AccountDataScreen({
    super.key,
    required this.onDeleteAccount,
    required this.apiClient,  // 新增
    required this.userId,     // 新增
  });
  ...
}
```

### Step 9: 更新 SettingsScreen 导入和调用

**文件**：`apps/lib/features/settings/presentation/screens/settings_screen.dart`

**修改**：
1. 更新导入：`import 'account_data_screen.dart';`（替换原 `account_delete_screen.dart`）
2. 更新 `_openAccountDelete()` 方法，传递新增参数：
```dart
Future<void> _openAccountData() async {
  final deleted = await Navigator.of(context).push<bool>(
    MaterialPageRoute<bool>(
      builder: (_) => AccountDataScreen(
        onDeleteAccount: widget.onDeleteAccount,
        apiClient: widget.apiClient,
        userId: widget.userId,
      ),
    ),
  );
  ...
}
```
3. 更新菜单项标题（如需要）

### Step 10: 添加 i18n 文案

**文件**：
- `apps/lib/l10n/app_zh.arb`
- `apps/lib/l10n/app_en.arb`
- `apps/lib/l10n/app_zh_hant.arb`

**新增文案**：
```json
"pointsLedgerTitle": "积分流水",
"pointsLedgerEmpty": "暂无流水记录",
"pointsLedgerLoadingMore": "加载中..."
```

## 验证步骤

### 后端验证

```bash
# 启动后端
./infra/scripts/app.sh start

# 测试 API
curl -H "Authorization: Bearer <token>" \
  "http://localhost:8000/api/v1/points/ledger?limit=10"
```

### 前端验证

```bash
cd apps
flutter run
# 导航到设置 -> 积分中心 -> 点击「查看流水」
```

## 风险与注意事项

1. **RLS 策略**：`points_ledger` 表已有 RLS，确保查询只返回当前用户数据
2. **游标分页**：使用 `created_at` 作为游标，注意处理相同时间戳的情况
3. **性能**：索引 `ix_points_ledger_user_created_at` 已存在，查询性能有保障
4. **空状态**：新用户可能无流水，需处理空列表情况

## 文件变更清单

### 后端新增/修改

| 文件 | 操作 | 说明 |
|------|------|------|
| `backend/src/v1/points/schemas.py` | 修改 | 新增 LedgerItem、LedgerListResponse |
| `backend/src/v1/points/repository.py` | 修改 | 新增 list_ledger() |
| `backend/src/v1/points/service.py` | 修改 | 新增 get_ledger_list() |
| `backend/src/v1/points/router.py` | 修改 | 新增 GET /ledger 端点 |

### 前端新增/修改

| 文件 | 操作 | 说明 |
|------|------|------|
| `apps/lib/features/points/data/models/ledger_item.dart` | 新增 | 流水项模型 |
| `apps/lib/features/points/data/apis/points_api.dart` | 修改 | 新增 getLedger() |
| `apps/lib/features/points/presentation/screens/points_ledger_screen.dart` | 新增 | 流水列表页面 |
| `apps/lib/features/settings/presentation/screens/coin_center_screen.dart` | 修改 | 添加入口按钮 |
| `apps/lib/l10n/app_*.arb` | 修改 | 新增文案 |