refactor: 重构项目结构

- 将 Python 代码移至 analyzer/ 目录（含 venv）
- 拆分 Go 服务器代码为模块化结构:
  - config/: 配置加载
  - model/: 请求/响应模型
  - service/: 业务逻辑
  - handler/: API处理器
- 添加 .gitignore 文件
- 删除旧的独立脚本文件

analyzer/cleaners/wechat.py

@@ -0,0 +1,288 @@
+"""
+微信账单清理模块
+"""
+import csv
+import re
+from decimal import Decimal
+
+from .base import (
+    BaseCleaner, parse_amount, format_amount,
+    is_in_date_range, create_arg_parser
+)
+from category import infer_category
+
+
+# 与支付宝对齐的表头（包含"复核等级"字段）
+ALIGNED_HEADER = [
+    "交易时间", "交易分类", "交易对方", "对方账号", "商品说明",
+    "收/支", "金额", "收/付款方式", "交易状态", "交易订单号", "商家订单号", "备注", "复核等级"
+]
+
+
+class WechatCleaner(BaseCleaner):
+    """微信账单清理器"""
+    
+    def clean(self) -> None:
+        """执行清理"""
+        self.print_header()
+        
+        # 读取数据
+        with open(self.input_file, "r", encoding="utf-8") as f:
+            reader = csv.reader(f)
+            header = next(reader)
+            rows = list(reader)
+        
+        self.stats["original_count"] = len(rows)
+        print(f"原始数据行数: {len(rows)}")
+        
+        # 第一步：按日期范围筛选
+        rows_filtered = [
+            row for row in rows
+            if row and is_in_date_range(row[0], self.start_date, self.end_date)
+        ]
+        self.stats["filtered_count"] = len(rows_filtered)
+        
+        date_desc = f"{self.start_date} ~ {self.end_date}" if self.start_date or self.end_date else "全部"
+        print(f"筛选后数据行数: {len(rows_filtered)} ({date_desc})")
+        
+        # 第二步：分离退款、支出、收入
+        refund_rows, expense_rows, income_rows = self._separate_rows(rows_filtered)
+        
+        print(f"退款条目数: {len(refund_rows)}")
+        print(f"支出条目数: {len(expense_rows)}")
+        print(f"其他收入条目数: {len(income_rows)}")
+        
+        # 第三步：处理退款（包括转账退款）
+        final_expense_rows, income_rows = self._process_refunds(expense_rows, income_rows)
+        
+        print(f"\n处理结果:")
+        print(f"  全额退款删除: {self.stats['fully_refunded']} 条")
+        print(f"  部分退款调整: {self.stats['partially_refunded']} 条")
+        print(f"  保留支出条目: {len(final_expense_rows)} 条")
+        print(f"  保留收入条目: {len(income_rows)} 条")
+        
+        # 第四步：转换为对齐格式并重新分类
+        aligned_expense = [self._convert_and_reclassify(r, remark) for r, remark in final_expense_rows]
+        aligned_income = [self._convert_and_reclassify((r, None), None) for r in income_rows]
+        
+        # 合并并排序
+        final_rows = aligned_expense + aligned_income
+        final_rows.sort(key=lambda x: x[0], reverse=True)
+        
+        # 统计复核数量
+        review_high_count = sum(1 for row in final_rows if row[-1] == "HIGH")
+        
+        self.stats["final_count"] = len(final_rows)
+        print(f"  最终保留行数: {len(final_rows)}")
+        if review_high_count > 0:
+            print(f"  高优先级复核: {review_high_count} 条（无法判断）")
+        
+        # 写入文件
+        self.write_output(ALIGNED_HEADER, final_rows)
+        
+        print(f"\n清理后的数据已保存到: {self.output_file}")
+        
+        # 统计支出
+        self._print_expense_summary(aligned_expense)
+    
+    def _separate_rows(self, rows: list) -> tuple[list, list, list]:
+        """分离退款、支出、收入记录"""
+        refund_rows = []
+        expense_rows = []
+        income_rows = []
+        
+        for row in rows:
+            if len(row) < 6:
+                continue
+            
+            transaction_type = row[1]
+            income_expense = row[4]
+            
+            if "-退款" in transaction_type:
+                refund_rows.append(row)
+            elif income_expense == "支出":
+                expense_rows.append(row)
+            elif income_expense == "收入" and "-退款" not in transaction_type:
+                income_rows.append(row)
+        
+        return refund_rows, expense_rows, income_rows
+    
+    def _process_refunds(self, expense_rows: list, income_rows: list) -> tuple[list, list]:
+        """
+        处理退款（包括转账退款）
+        
+        微信的退款有两种形式：
+        1. 状态标注：支出记录的"当前状态"列标注"已退款"
+        2. 转账退款：同一交易对方有收入记录（转账退回）
+        """
+        # 3.1 识别转账退款
+        transfer_refunds = {}
+        transfer_refund_rows = []
+        
+        for row in income_rows:
+            merchant = row[2].strip()
+            amount = parse_amount(row[5])
+            
+            # 检查是否有对应的支出记录
+            has_matching_expense = any(exp[2].strip() == merchant for exp in expense_rows)
+            
+            if has_matching_expense:
+                if merchant not in transfer_refunds:
+                    transfer_refunds[merchant] = Decimal("0")
+                transfer_refunds[merchant] += amount
+                transfer_refund_rows.append(row)
+        
+        # 从收入中移除已识别的转账退款
+        for row in transfer_refund_rows:
+            income_rows.remove(row)
+        
+        if transfer_refunds:
+            print(f"  识别到转账退款: {len(transfer_refunds)} 笔")
+        
+        # 3.2 处理支出记录
+        final_expense_rows = []
+        
+        for row in expense_rows:
+            status = row[7]
+            merchant = row[2].strip()
+            original_amount = parse_amount(row[5])
+            
+            # 计算总退款金额
+            status_refund = Decimal("0")
+            transfer_refund = transfer_refunds.get(merchant, Decimal("0"))
+            
+            if "已全额退款" in status:
+                self.stats["fully_refunded"] += 1
+                print(f"  全额退款删除: {row[0]} | {row[2]} | {row[3][:25]}... | {row[5]}")
+                continue
+            elif "已退款" in status:
+                status_refund = self._extract_refund_amount(status) or Decimal("0")
+            
+            total_refund = status_refund + transfer_refund
+            
+            if total_refund > 0:
+                if total_refund >= original_amount:
+                    self.stats["fully_refunded"] += 1
+                    print(f"  全额退款删除: {row[0]} | {row[2]} | {row[3][:25]}... | {row[5]}")
+                else:
+                    remaining = original_amount - total_refund
+                    new_row = row.copy()
+                    new_row[5] = f"￥{format_amount(remaining)}"
+                    remark = f"原金额{row[5]},退款￥{total_refund}"
+                    
+                    final_expense_rows.append((new_row, remark))
+                    self.stats["partially_refunded"] += 1
+                    print(f"  部分退款: {row[0]} | {row[2]} | 原{row[5]} -> ￥{format_amount(remaining)}")
+                    
+                    if merchant in transfer_refunds:
+                        del transfer_refunds[merchant]
+            else:
+                final_expense_rows.append((row, None))
+        
+        return final_expense_rows, income_rows
+    
+    def _extract_refund_amount(self, status: str) -> Decimal | None:
+        """从状态中提取已退款金额"""
+        match = re.search(r'已退款[（(]?￥?([\d.]+)[）)]?', status)
+        if match:
+            return Decimal(match.group(1))
+        if "已全额退款" in status:
+            return None
+        return Decimal("0")
+    
+    def _convert_and_reclassify(self, row_tuple: tuple, remark_override: str | None) -> list:
+        """
+        转换为对齐格式并重新分类
+        
+        微信原始字段:
+            0: 交易时间, 1: 交易类型, 2: 交易对方, 3: 商品,
+            4: 收/支, 5: 金额(元), 6: 支付方式, 7: 当前状态,
+            8: 交易单号, 9: 商户单号, 10: 备注
+        
+        对齐后字段:
+            交易时间, 交易分类, 交易对方, 对方账号, 商品说明,
+            收/支, 金额, 收/付款方式, 交易状态, 交易订单号, 商家订单号, 备注, 需复核
+        """
+        if isinstance(row_tuple, tuple):
+            row, remark = row_tuple
+        else:
+            row, remark = row_tuple, None
+        
+        remark = remark_override if remark_override else remark
+        
+        transaction_time = row[0]
+        merchant = row[2]
+        product = row[3]
+        income_expense = row[4]
+        amount = parse_amount(row[5])
+        payment_method = row[6]
+        status = row[7]
+        order_no = row[8]
+        merchant_order_no = row[9] if len(row) > 9 else ""
+        final_remark = remark if remark else (row[10] if len(row) > 10 else "/")
+        
+        # 重新分类（微信原始的"交易类型"太笼统）
+        category, is_certain = infer_category(merchant, product, income_expense)
+        
+        # 复核等级: 空=无需复核, HIGH=无法判断
+        review_mark = "" if is_certain else "HIGH"
+        
+        return [
+            transaction_time,
+            category,
+            merchant,
+            "/",  # 对方账号（微信无此字段）
+            product,
+            income_expense,
+            format_amount(amount),
+            payment_method,
+            status,
+            order_no,
+            merchant_order_no,
+            final_remark,
+            review_mark
+        ]
+    
+    def reclassify(self, rows: list) -> list:
+        """
+        重新分类微信账单
+        
+        微信账单在 _convert_and_reclassify 中已完成分类
+        此方法为接口兼容保留
+        """
+        return rows
+    
+    def _print_expense_summary(self, expense_rows: list):
+        """打印支出统计"""
+        total = Decimal("0")
+        categories = {}
+        
+        for row in expense_rows:
+            if row[5] == "支出":
+                amt = Decimal(row[6])
+                total += amt
+                cat = row[1]
+                categories[cat] = categories.get(cat, Decimal("0")) + amt
+        
+        print(f"清理后支出总额: ￥{total}")
+        print("\n=== 按分类统计 ===")
+        for cat, amt in sorted(categories.items(), key=lambda x: -x[1]):
+            print(f"  {cat}: ￥{amt}")
+
+
+def main():
+    """命令行入口"""
+    parser = create_arg_parser("清理微信支付账单数据")
+    args = parser.parse_args()
+    
+    from .base import compute_date_range
+    
+    cleaner = WechatCleaner(args.input_file, args.output_file)
+    start_date, end_date = compute_date_range(args)
+    cleaner.set_date_range(start_date, end_date)
+    cleaner.clean()
+
+
+if __name__ == "__main__":
+    main()
+