"""Persistent list of recently opened SQL files (~/.dbclient/recent_files.json)."""
import json
from pathlib import Path

_RECENT_FILE = Path.home() / ".dbclient" / "recent_files.json"
_MAX = 10


def load_recent() -> list[str]:
    """Return up to _MAX recent file paths that still exist on disk."""
    if not _RECENT_FILE.exists():
        return []
    try:
        with open(_RECENT_FILE, "r", encoding="utf-8") as f:
            data = json.load(f)
        return [p for p in data if isinstance(p, str) and Path(p).exists()][:_MAX]
    except Exception:
        return []


def add_recent(path: str) -> None:
    """Prepend path to the recent list, deduplicating and capping at _MAX."""
    recent = load_recent()
    recent = [p for p in recent if p != path]
    recent.insert(0, path)
    _save(recent[:_MAX])


def clear_recent() -> None:
    _save([])


def _save(data: list) -> None:
    _RECENT_FILE.parent.mkdir(parents=True, exist_ok=True)
    try:
        with open(_RECENT_FILE, "w", encoding="utf-8") as f:
            json.dump(data, f, indent=2)
    except Exception:
        pass