from __future__ import annotations

import random
from typing import Any, Dict, List

import torch
import numpy as np


# Label building
def build_labels(batch: Dict[str, torch.Tensor]) -> torch.Tensor:
    labels = batch["input_ids"].clone()  # (batch_size, seq_len)

    if "attention_mask" in batch:
        labels[batch["attention_mask"] == 0] = -100

    return labels  # (batch_size, seq_len)


# Reproducibility
def set_seed(seed: int) -> None:
    random.seed(seed)
    np.random.seed(seed)
    torch.manual_seed(seed)
    if torch.cuda.is_available():
        torch.cuda.manual_seed_all(seed)
        torch.backends.cudnn.benchmark = True


# Serialisation
def to_serializable(value: Any) -> Any:
    if isinstance(value, torch.Tensor):
        return value.detach().cpu().tolist()
    if isinstance(value, np.ndarray):
        return value.tolist()
    if isinstance(value, np.integer):
        return int(value)
    if isinstance(value, np.floating):
        return float(value)
    if isinstance(value, dict):
        return {k: to_serializable(v) for k, v in value.items()}
    if isinstance(value, (list, tuple)):
        return [to_serializable(v) for v in value]
    if hasattr(value, "__dataclass_fields__"):
        return {k: to_serializable(v) for k, v in value.__dict__.items()}
    return value


# Multi-seed helpers
def parse_seed_list(raw: str) -> List[int]:
    return [int(s.strip()) for s in raw.split(",") if s.strip()]