"""
MemoryService — conversation / memoir 的统一门面。
一期先实现基础接口签名，具体逻辑后续补充。
"""

from sqlalchemy.ext.asyncio import AsyncSession


class MemoryService:
    def __init__(self, db: AsyncSession):
        self._db = db

    async def ingest_transcript(
        self, user_id: str, conversation_id: str, transcript: str
    ) -> str:
        """Ingest conversation transcript into memory. Returns source_id."""
        raise NotImplementedError("Phase 2+ implementation")

    async def retrieve(self, user_id: str, query: str, *, top_k: int = 10) -> dict:
        """Retrieve relevant evidence for a query. 一期返回空结构，二期接入混合检索。"""
        return {
            "relevant_chunks": [],
            "relevant_summaries": [],
            "relevant_facts": [],
            "timeline_hints": [],
        }