First commit.

Signed-off-by: Chen Xiao <abigwc@gmail.com>

server/routers/doc_router.py

@@ -0,0 +1,69 @@
+import os
+import tempfile
+import pypandoc
+from typing import Optional
+from fastapi import APIRouter, HTTPException, Depends
+from fastapi.responses import FileResponse
+from pydantic import BaseModel
+from starlette.background import BackgroundTask
+import auth
+import db
+from formula_processor import preprocess_formulas
+
+router = APIRouter()
+
+class DocRequest(BaseModel):
+    markdown: str
+
+def remove_file(path: str):
+    try:
+        os.remove(path)
+    except Exception:
+        pass
+
+@router.post("/api/convert")
+async def convert_md_to_docx(req: DocRequest, current_user: Optional[dict] = Depends(auth.get_optional_user)):
+    try:
+        # 如果带有合法登录 token，则记录历史
+        if current_user:
+            db.add_history_record(current_user["id"], req.markdown)
+
+        try:
+            pypandoc.get_pandoc_version()
+        except OSError:
+            pypandoc.download_pandoc()
+
+        # ====== 公式预处理：统一各种定界符格式 ======
+        # 将 GPT/AI 生成内容中 \(...\)、\[...\]、缺失反斜杠的 [...] 和 (...)
+        # 全部转换为 Pandoc 可识别的标准 $...$ 和 $$...$$ 格式
+        processed_markdown = preprocess_formulas(req.markdown)
+
+        fd, tmp_path = tempfile.mkstemp(suffix=".docx")
+        os.close(fd)
+        
+        md_fd, md_tmp_path = tempfile.mkstemp(suffix=".md")
+        with os.fdopen(md_fd, 'w', encoding='utf-8') as f:
+            f.write(processed_markdown)
+        
+        pypandoc.convert_file(
+            md_tmp_path, 
+            'docx', 
+            format='markdown+tex_math_dollars', 
+            outputfile=tmp_path
+        )
+        os.remove(md_tmp_path)
+        
+        return FileResponse(
+            tmp_path, 
+            media_type='application/vnd.openxmlformats-officedocument.wordprocessingml.document', 
+            filename='document.docx',
+            background=BackgroundTask(remove_file, tmp_path)
+        )
+    except Exception as e:
+        print(f"Error during conversion: {e}")
+        raise HTTPException(status_code=500, detail=str(e))
+
+@router.get("/api/history")
+async def get_history(current_user: dict = Depends(auth.get_current_user)):
+    history = db.get_history_records(current_user["id"])
+    return {"history": history}