moment/src/backend/pyotherside_events.py

# SPDX-License-Identifier: LGPL-3.0-or-later

from abc import ABC
from dataclasses import dataclass, field
from typing import TYPE_CHECKING, Any, Optional

import pyotherside

from .models import SyncId
from .utils import serialize_value_for_qml

if TYPE_CHECKING:
    from .models.model_item import ModelItem


@dataclass
class PyOtherSideEvent:
    """Event that will be sent on instanciation to QML by PyOtherSide."""

    json_lists = False

    def __post_init__(self) -> None:
        # CPython 3.6 or any Python implemention >= 3.7 is required for correct
        # __dataclass_fields__ dict order.
        args = [
            serialize_value_for_qml(getattr(self, field), self.json_lists)
            for field in self.__dataclass_fields__  # type: ignore
        ]
        pyotherside.send(type(self).__name__, *args)


@dataclass
class ExitRequested(PyOtherSideEvent):
    """Request for the application to exit."""

    exit_code: int = 0


@dataclass
class AlertRequested(PyOtherSideEvent):
    """Request a window manager alert to be shown.

    Sets the urgency hint for compliant X11/Wayland window managers;
    flashes the taskbar icon on Windows.
    """


@dataclass
class CoroutineDone(PyOtherSideEvent):
    """Indicate that an asyncio coroutine finished."""

    uuid:      str                 = field()
    result:    Any                 = None
    exception: Optional[Exception] = None
    traceback: Optional[str]       = None


@dataclass
class LoopException(PyOtherSideEvent):
    """Indicate that an uncaught exception occured in the asyncio loop."""

    message:   str                 = field()
    exception: Optional[Exception] = field()
    traceback: Optional[str]       = None


@dataclass
class ModelEvent(ABC, PyOtherSideEvent):
    json_lists = True


@dataclass
class ModelItemInserted(ModelEvent):
    sync_id: SyncId      = field()
    index:   int         = field()
    item:    "ModelItem" = field()


@dataclass
class ModelItemFieldChanged(ModelEvent):
    sync_id:         SyncId = field()
    item_index_then: int    = field()
    item_index_now:  int    = field()
    changed_field:   str    = field()
    field_value:     Any    = field()


@dataclass
class ModelItemDeleted(ModelEvent):
    sync_id: SyncId = field()
    index:   int    = field()


@dataclass
class ModelCleared(ModelEvent):
    sync_id: SyncId = field()