feat: 支持ZIP压缩包上传（含密码保护）

analyzer/server.py

@@ -24,6 +24,7 @@ if sys.stdout.encoding != 'utf-8':
 from cleaners.base import compute_date_range_from_values
 from cleaners import AlipayCleaner, WechatCleaner
 from category import infer_category, get_all_categories, get_all_income_categories
+from converter import convert_bill_file
 
 # 应用版本
 APP_VERSION = "0.0.1"
@@ -72,6 +73,14 @@ class HealthResponse(BaseModel):
     version: str
 
 
+class ConvertResponse(BaseModel):
+    """文件转换响应"""
+    success: bool
+    bill_type: str
+    output_path: str
+    message: str
+
+
 # =============================================================================
 # 辅助函数
 # =============================================================================
@@ -85,7 +94,7 @@ def detect_bill_type(filepath: str) -> str | None:
     """
     try:
         with open(filepath, "r", encoding="utf-8") as f:
-            for _ in range(20):
+            for _ in range(50):  # 支付宝账单可能有较多的头部信息行
                 line = f.readline()
                 if not line:
                     break
@@ -337,6 +346,43 @@ async def detect_bill_type_api(file: UploadFile = File(...)):
             os.unlink(tmp_path)
 
 
+@app.post("/convert", response_model=ConvertResponse)
+async def convert_bill_file_api(file: UploadFile = File(...)):
+    """
+    转换账单文件格式
+    
+    支持:
+    - xlsx -> csv 转换
+    - GBK/GB2312 -> UTF-8 编码转换
+    
+    返回转换后的文件路径和检测到的账单类型
+    """
+    # 保存上传的文件到临时位置
+    suffix = Path(file.filename).suffix or ".csv"
+    with tempfile.NamedTemporaryFile(delete=False, suffix=suffix) as tmp:
+        shutil.copyfileobj(file.file, tmp)
+        input_path = tmp.name
+    
+    try:
+        # 调用转换函数
+        success, bill_type, output_path, message = convert_bill_file(input_path)
+        
+        if not success:
+            raise HTTPException(status_code=400, detail=message)
+        
+        return ConvertResponse(
+            success=True,
+            bill_type=bill_type,
+            output_path=output_path,
+            message=message
+        )
+    
+    finally:
+        # 清理输入临时文件（转换后的输出文件由调用方负责清理）
+        if os.path.exists(input_path):
+            os.unlink(input_path)
+
+
 # =============================================================================
 # 启动入口
 # =============================================================================