import json
import threading
from concurrent.futures import ThreadPoolExecutor
from datetime import datetime
from typing import Dict

from sqlalchemy import func, select

from pqai_agent.agents.simple_chat_agent import SimpleOpenAICompatibleChatAgent
from pqai_agent.data_models.agent_configuration import AgentConfiguration
from pqai_agent.data_models.agent_task import AgentTask
from pqai_agent.data_models.agent_task_detail import AgentTaskDetail
from pqai_agent.logging import logger
from pqai_agent.toolkit import get_tools
from pqai_agent_server.const.status_enum import AgentTaskStatus, get_agent_task_detail_status_desc, \
    AgentTaskDetailStatus, get_agent_task_status_desc


class AgentTaskManager:
    """任务管理器"""

    def __init__(self, session_maker):
        self.session_maker = session_maker
        self.task_events = {}  # 任务ID -> Event (用于取消任务)
        self.task_locks = {}  # 任务ID -> Lock (用于任务状态同步)
        self.running_tasks = set()
        self.executor = ThreadPoolExecutor(max_workers=10, thread_name_prefix='AgentTaskWorker')
        self.task_futures = {}  # 任务ID -> Future

    def get_agent_task(self, agent_task_id: int):
        """获取任务信息"""
        with self.session_maker() as session:
            return session.query(AgentTask).filter(AgentTask.id == agent_task_id).one()

    def get_agent_config(self, agent_id: int):
        """获取任务信息"""
        with self.session_maker() as session:
            return session.query(AgentConfiguration).filter(AgentConfiguration.id == agent_id).one()

    def get_in_progress_task(self):
        """获取执行中任务"""
        with self.session_maker() as session:
            return session.query(AgentTask).filter(AgentTask.status.in_([
                AgentTaskStatus.NOT_STARTED.value,
                AgentTaskStatus.IN_PROGRESS.value
            ])).all()

    def get_agent_task_details(self, task_id, parent_execution_id):
        """获取任务详情"""
        with self.session_maker() as session:
            # 创建子查询：统计每个父节点的子节点数量
            subquery = (
                select(
                    AgentTaskDetail.parent_execution_id.label('parent_id'),
                    func.count('*').label('child_count')
                )
                .where(AgentTaskDetail.parent_execution_id.isnot(None))
                .group_by(AgentTaskDetail.parent_execution_id)
                .subquery()
            )

            # 主查询：关联子查询，判断是否有子节点
            # 修正连接条件：使用parent_execution_id关联
            query = (
                select(
                    AgentTaskDetail,
                    (func.coalesce(subquery.c.child_count, 0) > 0).label('has_children')
                )
                .outerjoin(
                    subquery,
                    AgentTaskDetail.id == subquery.c.parent_id  # 使用当前记录的id匹配子查询的parent_id
                )
            ).where(AgentTaskDetail.agent_task_id == task_id).where(
                AgentTaskDetail.parent_execution_id == parent_execution_id)
            # 执行查询
            return session.execute(query).all()

    def save_agent_task_details_batch(self, agent_task_details: list, agent_task_id: int, message: str):
        """批量保存子任务到数据库"""
        try:
            with self.session_maker() as session:
                with session.begin():
                    session.add_all(agent_task_details)
                    session.query(AgentTask).filter(
                        AgentTask.id == agent_task_id).update(
                        {"status": AgentTaskStatus.COMPLETED.value, "output": message, "update_time": datetime.now()})
                    session.commit()
        except Exception as e:
            logger.error(e)
            raise Exception(e)

    def update_task_failed(self, task_id, error_message: str):
        """更新任务失败"""
        with self.session_maker() as session:
            session.query(AgentTask).filter(AgentTask.id == task_id).update(
                {"status": AgentTaskStatus.FAILED.value, "error_message": error_message, "update_time": datetime.now()})
            session.commit()

    def update_task_status(self, task_id, status):
        """更新任务状态"""
        with self.session_maker() as session:
            session.query(AgentTask).filter(AgentTask.id == task_id).update(
                {"status": status, "update_time": datetime.now()})
            session.commit()

    def get_agent_task_list(self, page_num: int, page_size: int) -> Dict:
        with self.session_maker() as session:
            # 计算偏移量
            offset = (page_num - 1) * page_size
            # 查询分页数据
            result = (session.query(AgentTask, AgentConfiguration)
                      .outerjoin(AgentConfiguration, AgentTask.agent_id == AgentConfiguration.id)
                      .limit(page_size).offset(offset).all())
            # 查询总记录数
            total = session.query(func.count(AgentTask.id)).scalar()

            total_page = total // page_size + 1 if total % page_size > 0 else total // page_size
            total_page = 1 if total_page <= 0 else total_page
            response_data = [
                {
                    "id": agent_task.id,
                    "agentName": agent_configuration.name,
                    "statusName": get_agent_task_status_desc(agent_task.status),
                    "startTime": agent_task.start_time.strftime("%Y-%m-%d %H:%M:%S"),
                    "endTime": agent_task.start_time.strftime(
                        "%Y-%m-%d %H:%M:%S") if agent_task.start_time is not None else None,
                    "createUser": agent_task.create_user,
                    "input": agent_task.input,
                    "output": agent_task.output,
                    "createTime": agent_task.create_time.strftime("%Y-%m-%d %H:%M:%S"),
                    "updateTime": agent_task.update_time.strftime("%Y-%m-%d %H:%M:%S")
                }
                for agent_task, agent_configuration in result
            ]
            return {
                "currentPage": page_num,
                "pageSize": page_size,
                "totalSize": total_page,
                "total": total,
                "list": response_data,
            }

    def create_task(self, agent_id: int, task_prompt: str):
        """创建新任务"""
        with self.session_maker() as session:
            agent_config = session.get(AgentConfiguration, agent_id)
            agent_task = AgentTask(agent_id=agent_id,
                                   status=AgentTaskStatus.NOT_STARTED.value,
                                   start_time=datetime.now(),
                                   input=task_prompt,
                                   tools=agent_config.tools)
            session.add(agent_task)
            session.commit()  # 显式提交
            task_id = agent_task.id
        # 异步执行创建任务
        self.executor.submit(self._execute_task, task_id)

    def _process_task(self, task_id: int):
        try:
            self.update_task_status(task_id, AgentTaskStatus.IN_PROGRESS.value)
            agent_task = self.get_agent_task(task_id)
            agent_config = self.get_agent_config(agent_task.agent_id)
            tools = get_tools(json.loads(agent_config.tools))
            chat_agent = SimpleOpenAICompatibleChatAgent(model=agent_config.execution_model,
                                                         system_prompt=agent_config.system_prompt,
                                                         tools=tools)
            message = chat_agent.run(agent_task.input)
            agent_task_details = chat_agent.get_agent_task_details()
            for agent_task_detail in agent_task_details:
                agent_task_detail.agent_task_id = task_id
                agent_task_detail.status = AgentTaskDetailStatus.SUCCESS.value
            self.save_agent_task_details_batch(agent_task_details, task_id, message)
        except Exception as e:
            logger.error(e)
            self.update_task_failed(task_id, str(e))

    def recover_tasks(self):
        """服务启动时恢复未完成的任务"""

        in_progress_tasks = self.get_in_progress_task()

        for task in in_progress_tasks:
            task_id = task.id
            # 重新提交任务
            self._execute_task(task_id)

    def _execute_task(self, task_id: int):
        """提交任务到线程池执行"""
        # 确保任务状态一致性
        if task_id in self.running_tasks:
            return

        # 创建任务事件和锁
        if task_id not in self.task_events:
            self.task_events[task_id] = threading.Event()
        if task_id not in self.task_locks:
            self.task_locks[task_id] = threading.Lock()

        # 提交到线程池
        future = self.executor.submit(self._process_task, task_id)
        self.task_futures[task_id] = future

        # 标记任务为运行中
        with self.task_locks[task_id]:
            self.running_tasks.add(task_id)

    def get_agent_task_detail(self, agent_task_id, parent_execution_id):
        agent_task = self.get_agent_task(agent_task_id)
        agent_task_details = self.get_agent_task_details(agent_task_id, parent_execution_id)
        agent_task_detail_datas = [
            {
                "id": agent_task_detail.id,
                "agentTaskId": agent_task_detail.agent_task_id,
                "executorType": agent_task_detail.executor_type,
                "statusName": get_agent_task_detail_status_desc(agent_task_detail.status),
                "inputData": agent_task_detail.input_data,
                "executorName": agent_task_detail.executor_name,
                "reasoning": agent_task_detail.reasoning,
                "outputData": agent_task_detail.output_data,
                "errorMessage": agent_task_detail.error_message,
                "hasChildren": has_children,
                "createTime": agent_task_detail.create_time.strftime("%Y-%m-%d %H:%M:%S"),
                "updateTime": agent_task_detail.update_time.strftime("%Y-%m-%d %H:%M:%S")
            }
            for agent_task_detail, has_children in agent_task_details
        ]
        return {
            "input": agent_task.input,
            "tools": agent_task.tools,
            "agentTaskDetails": agent_task_detail_datas
        }