"""Storage path helpers — multi-instance via BOT_INSTANCE_ID env var.

Without BOT_INSTANCE_ID (default):
  db_path("prefix.db")     -> bot/db/prefix.db
  jsondb_path("x.json")    -> bot/jsondb/x.json

With BOT_INSTANCE_ID=prod-a:
  db_path("prefix.db")     -> bot/db/prod-a/prefix.db
  jsondb_path("x.json")    -> bot/db/prod-a/jsondb/x.json
"""
from __future__ import annotations

import os
from pathlib import Path

_BOT_ROOT = Path(__file__).resolve().parent.parent
_INSTANCE_ID = os.getenv("BOT_INSTANCE_ID", "").strip()


def _instance_db_dir() -> Path:
    base = _BOT_ROOT / "db"
    if _INSTANCE_ID:
        base = base / _INSTANCE_ID
    base.mkdir(parents=True, exist_ok=True)
    return base


def db_path(filename: str) -> str:
    """SQLite and other files under bot/db/ (or bot/db/<instance>/)."""
    return str(_instance_db_dir() / filename)


def jsondb_path(filename: str) -> str:
    """JSON config files — bot/jsondb/ or bot/db/<instance>/jsondb/."""
    if _INSTANCE_ID:
        base = _instance_db_dir() / "jsondb"
    else:
        base = _BOT_ROOT / "jsondb"
    base.mkdir(parents=True, exist_ok=True)
    return str(base / filename)


def bot_root_json_path(filename: str) -> str:
    """Legacy JSON at bot/<filename> (e.g. ignore.json) — isolated per instance when set."""
    if _INSTANCE_ID:
        return jsondb_path(filename)
    return str(_BOT_ROOT / filename)


def resolve_db_path(path: str) -> str:
    """Normalize legacy 'db/file.db' strings (safety net for API layer)."""
    if path.startswith("db/"):
        return db_path(path[3:])
    if path.startswith("jsondb/"):
        return jsondb_path(path[7:])
    return path