"""客户长期记忆的 Neo4j 关系镜像。"""

from __future__ import annotations

from config.database.neo4j import client as configured_client


class Neo4jMemoryStore:
    """保存客户节点、记忆节点及其 HAS_MEMORY 关系。"""

    def __init__(self, driver=None):
        self.driver = driver or configured_client()

    async def upsert(self, memory) -> str:
        """写入客户和记忆节点，返回图谱记忆节点 ID。"""
        memory_id = str(memory.id)
        query = """
        MERGE (c:Customer {customer_id: $customer_id})
        MERGE (m:CustomerMemory {memory_id: $memory_id})
        SET m.memory_type = $memory_type,
            m.tag = $tag,
            m.content = $content,
            m.status = $status
        MERGE (c)-[:HAS_MEMORY]->(m)
        RETURN m.memory_id AS memory_id
        """
        async with self.driver.session() as session:
            record = await session.run(
                query,
                customer_id=int(memory.customer_id),
                memory_id=memory_id,
                memory_type=memory.memory_type,
                tag=memory.tag,
                content=memory.content,
                status=memory.status,
            )
            row = await record.single()
        return row["memory_id"] if row else memory_id

    async def list_by_customer(self, customer_id: int, *, limit: int = 100) -> list[dict]:
        """按客户查询图谱记忆关系。"""
        query = """
        MATCH (c:Customer {customer_id: $customer_id})-[:HAS_MEMORY]->(m:CustomerMemory)
        RETURN m.memory_id AS memory_id, m.memory_type AS memory_type,
               m.tag AS tag, m.content AS content, m.status AS status
        LIMIT $limit
        """
        async with self.driver.session() as session:
            result = await session.run(query, customer_id=int(customer_id), limit=limit)
            return [dict(record) async for record in result]

    async def delete(self, memory_id: int | str) -> None:
        """删除记忆节点及其关系。"""
        query = "MATCH (m:CustomerMemory {memory_id: $memory_id}) DETACH DELETE m"
        async with self.driver.session() as session:
            await session.run(query, memory_id=str(memory_id))


__all__ = ["Neo4jMemoryStore"]