import celery.app.task
import importlib
import kombu.utils.json
from typing import (
    Any,
)

class Task(celery.app.task.Task):
    def __call__(self, *args, **kwargs):
        res = super().__call__(*args, **kwargs)
        return self._dumps(res)

    @classmethod
    def _loads(self, data_str: str) -> Any:
        data = kombu.utils.json.loads(data_str)

        if isinstance(data, dict) and data.get('type') == 'dataclass_json':
            module_name = data['module']
            class_names = data['_class'].split('.')

            m = importlib.import_module(module_name)

            c = m
            for current_name in class_names:
                c = getattr(c, current_name)

            return c(**data['data'])
        else:
            return data

    @classmethod
    def _dumps(self, data: Any) -> str:
        if hasattr(data, 'to_dict'):
            return kombu.utils.json.dumps(dict(
                type='dataclass_json',
                module=data.__class__.__module__,
                _class=data.__class__.__qualname__,
                data=data.to_dict(),
            ))
        else:
            return kombu.utils.json.dumps(data)

def kombu_register_json_dataclass():
    import kombu.serialization
    kombu.serialization.register(
        'json-dataclass',
        Task._dumps,
        Task._loads,
        content_type='application/json',
        content_encoding='text',
    )