from __future__ import annotations

import uuid
from typing import Any
from datetime import datetime

from sqlalchemy.orm import Session

from app.models.attachment import Attachment
from app.models.message import Message
from app.models.request import Request
from app.models.status_history import StatusHistory


def actor_admin_uuid(admin: dict[str, Any] | None) -> uuid.UUID | None:
    if not admin:
        return None
    raw = str(admin.get("sub") or "").strip()
    if not raw:
        return None
    try:
        return uuid.UUID(raw)
    except ValueError:
        return None


def freeze_request_messages_and_attachments(db: Session, request_id: uuid.UUID) -> None:
    db.query(Message).filter(Message.request_id == request_id, Message.immutable.is_(False)).update(
        {"immutable": True},
        synchronize_session=False,
    )
    db.query(Attachment).filter(Attachment.request_id == request_id, Attachment.immutable.is_(False)).update(
        {"immutable": True},
        synchronize_session=False,
    )


def register_status_history(
    db: Session,
    request: Request,
    from_status: str,
    to_status: str,
    *,
    admin: dict[str, Any] | None = None,
    comment: str | None = None,
    important_date_at: datetime | None = None,
    responsible: str = "Администратор системы",
) -> None:
    db.add(
        StatusHistory(
            request_id=request.id,
            from_status=str(from_status or "").strip() or None,
            to_status=str(to_status or "").strip(),
            changed_by_admin_id=actor_admin_uuid(admin),
            comment=comment,
            important_date_at=important_date_at,
            responsible=responsible,
        )
    )


def apply_status_change_effects(
    db: Session,
    request: Request,
    *,
    from_status: str,
    to_status: str,
    admin: dict[str, Any] | None = None,
    comment: str | None = None,
    important_date_at: datetime | None = None,
    responsible: str = "Администратор системы",
) -> None:
    old_code = str(from_status or "").strip()
    new_code = str(to_status or "").strip()
    if not new_code or old_code == new_code:
        return
    freeze_request_messages_and_attachments(db, request.id)
    register_status_history(
        db,
        request,
        old_code,
        new_code,
        admin=admin,
        comment=comment,
        important_date_at=important_date_at,
        responsible=responsible,
    )