"""Agent 工具集 - 任务相关"""

from langchain_core.tools import tool
from app.database import async_session
from app.models.task import Task
from app.agents.context import get_current_user
from sqlalchemy import select
import asyncio

_executor = None


def _run_async(coro, timeout: int = 30):
    try:
        loop = asyncio.get_running_loop()
        future = loop.run_in_executor(_executor or __import__("concurrent.futures").ThreadPoolExecutor(), lambda: asyncio.run(coro))
        return future.result(timeout=timeout)
    except RuntimeError:
        return asyncio.run(coro)


@tool
def get_tasks(status: str | None = None, limit: int = 20) -> str:
    """
    获取用户当前的任务列表。

    Args:
        status: 可选，筛选任务状态 (todo/in_progress/done/blocked)
        limit: 返回数量，默认20

    Returns:
        任务列表
    """
    uid = get_current_user()

    async def _get():
        async with async_session() as db:
            from app.models.user import User
            query = (
                select(Task)
                .join(User, User.id == Task.user_id)
                .where(User.id == uid)
            )
            if status:
                query = query.where(Task.status == status)
            query = query.order_by(Task.priority.desc(), Task.updated_at.desc()).limit(limit)
            result = await db.execute(query)
            tasks = result.scalars().all()
            if not tasks:
                return "暂无任务"
            lines = []
            for t in tasks:
                lines.append(
                    f"- [{t.id[:8]}] {t.title} | "
                    f"状态:{t.status} | 优先级:{t.priority} | 截止:{t.due_date or '无'}"
                )
            return "\n".join(lines)

    try:
        return _run_async(_get())
    except Exception as e:
        return f"获取任务失败: {str(e)}"


@tool
def create_task(title: str, description: str = "", priority: int = 2, due_date: str | None = None) -> str:
    """
    创建新任务。

    Args:
        title: 任务标题（必填）
        description: 任务描述
        priority: 优先级 1-4，数字越大优先级越高，默认2
        due_date: 截止日期，格式 YYYY-MM-DD

    Returns:
        创建结果
    """
    uid = get_current_user()

    async def _create():
        async with async_session() as db:
            task = Task(
                user_id=uid,
                title=title,
                description=description,
                priority=priority,
                due_date=due_date,
                status="todo",
            )
            db.add(task)
            await db.commit()
            await db.refresh(task)
            return f"任务创建成功: [{task.id[:8]}] {title}"

    try:
        return _run_async(_create())
    except Exception as e:
        return f"创建任务失败: {str(e)}"


@tool
def update_task_status(task_id: str, status: str) -> str:
    """
    更新任务状态。

    Args:
        task_id: 任务ID（完整ID或前8位）
        status: 新状态 (todo/in_progress/done/blocked)

    Returns:
        更新结果
    """
    uid = get_current_user()

    async def _update():
        async with async_session() as db:
            from app.models.user import User
            query = (
                select(Task)
                .join(User, User.id == Task.user_id)
                .where(User.id == uid)
            )
            if len(task_id) == 8:
                query = query.where(Task.id.like(f"{task_id}%"))
            else:
                query = query.where(Task.id == task_id)
            result = await db.execute(query)
            task = result.scalar_one_or_none()
            if not task:
                return f"任务不存在: {task_id}"
            task.status = status
            await db.commit()
            return f"任务状态已更新: {task.title} -> {status}"

    try:
        return _run_async(_update())
    except Exception as e:
        return f"更新任务失败: {str(e)}"


__all__ = ["get_tasks", "create_task", "update_task_status"]