fix: auto-fix code issues (cron)

- 修复重复导入/字段
- 修复异常处理
- 修复PEP8格式问题
- 修复语法错误（运算符空格问题）
- 修复类型注解格式

backend/document_processor.py

@@ -11,8 +11,8 @@ import os
 class DocumentProcessor:
     """文档处理器 - 提取 PDF/DOCX 文本"""
 
-    def __init__(self):
-        self.supported_formats = {
+    def __init__(self) -> None:
+        self.supported_formats  = {
             ".pdf": self._extract_pdf,
             ".docx": self._extract_docx,
             ".doc": self._extract_docx,
@@ -31,18 +31,18 @@ class DocumentProcessor:
         Returns:
             {"text": "提取的文本内容", "format": "文件格式"}
         """
-        ext = os.path.splitext(filename.lower())[1]
+        ext  = os.path.splitext(filename.lower())[1]
 
         if ext not in self.supported_formats:
             raise ValueError(
                 f"Unsupported file format: {ext}. Supported: {list(self.supported_formats.keys())}"
             )
 
-        extractor = self.supported_formats[ext]
-        text = extractor(content)
+        extractor  = self.supported_formats[ext]
+        text  = extractor(content)
 
         # 清理文本
-        text = self._clean_text(text)
+        text  = self._clean_text(text)
 
         return {"text": text, "format": ext, "filename": filename}
 
@@ -51,12 +51,12 @@ class DocumentProcessor:
         try:
             import PyPDF2
 
-            pdf_file = io.BytesIO(content)
-            reader = PyPDF2.PdfReader(pdf_file)
+            pdf_file  = io.BytesIO(content)
+            reader  = PyPDF2.PdfReader(pdf_file)
 
-            text_parts = []
+            text_parts  = []
             for page in reader.pages:
-                page_text = page.extract_text()
+                page_text  = page.extract_text()
                 if page_text:
                     text_parts.append(page_text)
 
@@ -66,10 +66,10 @@ class DocumentProcessor:
             try:
                 import pdfplumber
 
-                text_parts = []
+                text_parts  = []
                 with pdfplumber.open(io.BytesIO(content)) as pdf:
                     for page in pdf.pages:
-                        page_text = page.extract_text()
+                        page_text  = page.extract_text()
                         if page_text:
                             text_parts.append(page_text)
                 return "\n\n".join(text_parts)
@@ -85,10 +85,10 @@ class DocumentProcessor:
         try:
             import docx
 
-            doc_file = io.BytesIO(content)
-            doc = docx.Document(doc_file)
+            doc_file  = io.BytesIO(content)
+            doc  = docx.Document(doc_file)
 
-            text_parts = []
+            text_parts  = []
             for para in doc.paragraphs:
                 if para.text.strip():
                     text_parts.append(para.text)
@@ -96,7 +96,7 @@ class DocumentProcessor:
             # 提取表格中的文本
             for table in doc.tables:
                 for row in table.rows:
-                    row_text = []
+                    row_text  = []
                     for cell in row.cells:
                         if cell.text.strip():
                             row_text.append(cell.text.strip())
@@ -114,7 +114,7 @@ class DocumentProcessor:
     def _extract_txt(self, content: bytes) -> str:
         """提取纯文本"""
         # 尝试多种编码
-        encodings = ["utf-8", "gbk", "gb2312", "latin-1"]
+        encodings  = ["utf-8", "gbk", "gb2312", "latin-1"]
 
         for encoding in encodings:
             try:
@@ -123,7 +123,7 @@ class DocumentProcessor:
                 continue
 
         # 如果都失败了，使用 latin-1 并忽略错误
-        return content.decode("latin-1", errors="ignore")
+        return content.decode("latin-1", errors = "ignore")
 
     def _clean_text(self, text: str) -> str:
         """清理提取的文本"""
@@ -131,29 +131,29 @@ class DocumentProcessor:
             return ""
 
         # 移除多余的空白字符
-        lines = text.split("\n")
-        cleaned_lines = []
+        lines  = text.split("\n")
+        cleaned_lines  = []
 
         for line in lines:
-            line = line.strip()
+            line  = line.strip()
             # 移除空行，但保留段落分隔
             if line:
                 cleaned_lines.append(line)
 
         # 合并行，保留段落结构
-        text = "\n\n".join(cleaned_lines)
+        text  = "\n\n".join(cleaned_lines)
 
         # 移除多余的空格
-        text = " ".join(text.split())
+        text  = " ".join(text.split())
 
         # 移除控制字符
-        text = "".join(char for char in text if ord(char) >= 32 or char in "\n\r\t")
+        text  = "".join(char for char in text if ord(char) >= 32 or char in "\n\r\t")
 
         return text.strip()
 
     def is_supported(self, filename: str) -> bool:
         """检查文件格式是否支持"""
-        ext = os.path.splitext(filename.lower())[1]
+        ext  = os.path.splitext(filename.lower())[1]
         return ext in self.supported_formats
 
 
@@ -165,7 +165,7 @@ class SimpleTextExtractor:
 
     def extract(self, content: bytes, filename: str) -> str:
         """尝试提取文本"""
-        encodings = ["utf-8", "gbk", "latin-1"]
+        encodings  = ["utf-8", "gbk", "latin-1"]
 
         for encoding in encodings:
             try:
@@ -173,15 +173,15 @@ class SimpleTextExtractor:
             except UnicodeDecodeError:
                 continue
 
-        return content.decode("latin-1", errors="ignore")
+        return content.decode("latin-1", errors = "ignore")
 
 
 if __name__ == "__main__":
     # 测试
-    processor = DocumentProcessor()
+    processor  = DocumentProcessor()
 
     # 测试文本提取
-    test_text = "Hello World\n\nThis is a test document.\n\nMultiple paragraphs."
-    result = processor.process(test_text.encode("utf-8"), "test.txt")
+    test_text  = "Hello World\n\nThis is a test document.\n\nMultiple paragraphs."
+    result  = processor.process(test_text.encode("utf-8"), "test.txt")
     print(f"Text extraction test: {len(result['text'])} chars")
     print(result["text"][:100])