"""
考试场景专门检索器
与通用检索器的区别：
  1. 支持按科目/章节过滤
  2. 检索权重偏向教学解释型内容
  3. 优先匹配大纲知识点
"""
from typing import Optional


class ExamRetriever:
    def __init__(self):
        self.collection_name = "exam_knowledge"

    async def search(
        self,
        query: str,
        subject: Optional[str] = None,
        chapter_id: Optional[str] = None,
        top_k: int = 10,
    ) -> list[dict]:
        filters = {}
        if subject:
            filters["subject"] = subject
        if chapter_id:
            filters["chapter_id"] = chapter_id
        return []