# =====================================================
# Apckeyl Framework
# Version 1.0
# task_manager.py
# =====================================================

"""
Apckeyl Task Manager.

Version 1.0

Создаёт и хранит задачи Control Plane.

На этом этапе Task Manager работает только
в памяти процесса.

Постоянное хранение, очередь и внешняя база
будут добавлены позже.
"""

from datetime import datetime, timezone
from itertools import count

from control_plane import control_plane


# =====================================================
# Task Manager
# =====================================================

class TaskManager:

    def __init__(self, control_plane_instance=None):

        if control_plane_instance is None:
            control_plane_instance = control_plane

        self.control_plane = control_plane_instance

        self._tasks = {}

        self._counter = count(1)


    # =================================================
    # Create Task
    # =================================================

    def create_task(
        self,
        task_type,
        payload=None,
    ):

        if not task_type:
            raise ValueError(
                "task_type is required"
            )

        module = self.control_plane.resolve_task(
            task_type
        )

        number = next(
            self._counter
        )

        task_id = (
            f"task_{number:06d}"
        )

        task = {

            "task_id": task_id,

            "task_type": task_type,

            "status": "created",

            "module_id": module[
                "module_id"
            ],

            "module_name": module[
                "module_name"
            ],

            "payload": payload,

            "created_at": (
                datetime.now(
                    timezone.utc
                ).isoformat()
            ),
        }

        self._tasks[
            task_id
        ] = task

        return dict(task)


    # =================================================
    # Get Task
    # =================================================

    def get_task(
        self,
        task_id,
    ):

        task = self._tasks.get(
            task_id
        )

        if task is None:
            return None

        return dict(task)


    # =================================================
    # Update Status
    # =================================================

    def update_status(
        self,
        task_id,
        status,
    ):

        task = self._tasks.get(
            task_id
        )

        if task is None:

            raise KeyError(
                f"Unknown task: {task_id}"
            )

        task["status"] = status

        return dict(task)


    # =================================================
    # List Tasks
    # =================================================

    def list_tasks(self):

        return [
            dict(task)
            for task
            in self._tasks.values()
        ]


    # =================================================
    # Delete Task
    # =================================================

    def delete_task(
        self,
        task_id,
    ):

        if task_id in self._tasks:

            del self._tasks[
                task_id
            ]


# =====================================================
# Default Task Manager
# =====================================================

task_manager = TaskManager()