from __future__ import annotations

from dataclasses import dataclass, field
from typing import Any, Dict, List, Literal, Optional


WorkerCommandKind = Literal["preload", "forecast", "shutdown"]
WorkerResponseKind = Literal["preload", "forecast", "shutdown", "status", "exit"]


@dataclass(frozen=True)
class ForecastWorkerCommand:
    kind: WorkerCommandKind
    job_id: str
    model_key: str
    df_records: List[Dict[str, Any]] = field(default_factory=list)
    horizon: int = 0
    interval: str = ""
    step_seconds: int = 0
    symbol: str = ""


@dataclass(frozen=True)
class ForecastWorkerResponse:
    kind: WorkerResponseKind
    job_id: str
    model_key: str
    success: bool
    payload: Optional[Dict[str, Any]] = None
    error: Optional[str] = None
    device: str = "not_loaded"
    loaded: bool = False
    pid: int = 0