"""
Trace Storage Protocol - Trace 存储接口定义

使用 Protocol 定义接口，允许不同的存储实现（内存、PostgreSQL、Neo4j 等）
"""

from typing import Protocol, List, Optional, Dict, Any, runtime_checkable

from .models import Trace, Message
from .goal_models import GoalTree, Goal


@runtime_checkable
class TraceStore(Protocol):
    """Trace + Message + GoalTree 存储接口"""

    # ===== Trace 操作 =====

    async def create_trace(self, trace: Trace) -> str:
        """
        创建新的 Trace

        Args:
            trace: Trace 对象

        Returns:
            trace_id
        """
        ...

    async def get_trace(self, trace_id: str) -> Optional[Trace]:
        """获取 Trace"""
        ...

    async def update_trace(self, trace_id: str, **updates) -> None:
        """
        更新 Trace

        Args:
            trace_id: Trace ID
            **updates: 要更新的字段
        """
        ...

    async def list_traces(
        self,
        mode: Optional[str] = None,
        agent_type: Optional[str] = None,
        uid: Optional[str] = None,
        status: Optional[str] = None,
        limit: int = 50
    ) -> List[Trace]:
        """列出 Traces"""
        ...

    # ===== GoalTree 操作 =====

    async def get_goal_tree(self, trace_id: str) -> Optional[GoalTree]:
        """
        获取 GoalTree

        Args:
            trace_id: Trace ID

        Returns:
            GoalTree 对象，如果不存在返回 None
        """
        ...

    async def update_goal_tree(self, trace_id: str, tree: GoalTree) -> None:
        """
        更新完整 GoalTree

        Args:
            trace_id: Trace ID
            tree: GoalTree 对象
        """
        ...

    async def add_goal(self, trace_id: str, goal: Goal) -> None:
        """
        添加 Goal 到 GoalTree

        Args:
            trace_id: Trace ID
            goal: Goal 对象
        """
        ...

    async def update_goal(self, trace_id: str, goal_id: str, **updates) -> None:
        """
        更新 Goal 字段

        Args:
            trace_id: Trace ID
            goal_id: Goal ID
            **updates: 要更新的字段（如 status, summary, self_stats, cumulative_stats）
        """
        ...

    # ===== Message 操作 =====

    async def add_message(self, message: Message) -> str:
        """
        添加 Message

        自动更新关联 Goal 的 stats（self_stats 和祖先的 cumulative_stats）

        Args:
            message: Message 对象

        Returns:
            message_id
        """
        ...

    async def get_message(self, message_id: str) -> Optional[Message]:
        """获取 Message"""
        ...

    async def get_trace_messages(
        self,
        trace_id: str
    ) -> List[Message]:
        """
        获取 Trace 的所有 Messages（按 sequence 排序）

        Args:
            trace_id: Trace ID

        Returns:
            Message 列表
        """
        ...

    async def get_messages_by_goal(
        self,
        trace_id: str,
        goal_id: str
    ) -> List[Message]:
        """
        获取指定 Goal 关联的所有 Messages

        Args:
            trace_id: Trace ID
            goal_id: Goal ID

        Returns:
            Message 列表
        """
        ...

    async def update_message(self, message_id: str, **updates) -> None:
        """
        更新 Message 字段（用于状态变更、错误记录等）

        Args:
            message_id: Message ID
            **updates: 要更新的字段
        """
        ...

    # ===== 事件流操作（用于 WebSocket 断线续传）=====

    async def get_events(
        self,
        trace_id: str,
        since_event_id: int = 0
    ) -> List[Dict[str, Any]]:
        """
        获取事件流（用于 WS 断线续传）

        Args:
            trace_id: Trace ID
            since_event_id: 从哪个事件 ID 开始（0 表示全部）

        Returns:
            事件列表（按 event_id 排序）
        """
        ...

    async def append_event(
        self,
        trace_id: str,
        event_type: str,
        payload: Dict[str, Any]
    ) -> int:
        """
        追加事件，返回 event_id

        Args:
            trace_id: Trace ID
            event_type: 事件类型
            payload: 事件数据

        Returns:
            event_id: 新事件的 ID
        """
        ...