import json
import re
from pathlib import Path
from typing import Any, Callable, Iterable


def save_to_json(data: Any, filename: str | Path) -> None:
    path = Path(filename)
    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_text(json.dumps(data, ensure_ascii=False, indent=2), encoding="utf-8")


def first_non_empty(values: Iterable[Any]) -> Any | None:
    for value in values:
        if value not in (None, "", [], {}, ()):
            return value
    return None


def deep_find_key(obj, target_keys: set[str], max_depth: int = 64, _depth: int = 0) -> list:
    # Рекурсивно ищет значения по набору ключей в произвольном JSON-дереве.
    found = []
    if _depth >= max_depth:
        return found
    if isinstance(obj, dict):
        for key, value in obj.items():
            if key.lower() in target_keys:
                found.append(value)
            found.extend(deep_find_key(value, target_keys, max_depth=max_depth, _depth=_depth + 1))
    elif isinstance(obj, list):
        for item in obj:
            found.extend(deep_find_key(item, target_keys, max_depth=max_depth, _depth=_depth + 1))
    return found


def deep_find_all_keys(
    payloads: list,
    field_map: dict[str, set[str]],
    max_depth: int = 64,
) -> dict[str, list]:
    """Извлекает все нужные поля за один проход по JSON."""
    # Готовим обратную карту: нормализованный ключ -> имя поля.
    reverse: dict[str, str] = {}
    for field_name, keys in field_map.items():
        for k in keys:
            reverse[k.lower()] = field_name

    result: dict[str, list] = {f: [] for f in field_map}

    def _recurse(obj: Any, depth: int) -> None:
        if depth >= max_depth:
            return
        if isinstance(obj, dict):
            for k, v in obj.items():
                field = reverse.get(k.lower())
                if field is not None:
                    result[field].append(v)
                _recurse(v, depth + 1)
        elif isinstance(obj, list):
            for item in obj:
                _recurse(item, depth + 1)

    for payload in payloads:
        _recurse(payload, 0)

    return result