"""Tunetti configuration — stored at ~/.config/tunetti/config.json ."""

import json
from pathlib import Path

# ── Config file location (XDG compliant) ──────────────────────────────────
CONFIG_DIR = Path.home() / ".config" / "tunetti"
CONFIG_FILE = CONFIG_DIR / "config.json"

# Legacy config in the project directory (for migration).
_LEGACY_FILE = Path(__file__).parent / "tunetti_config.json"

DEFAULT_CONFIG: dict = {
    # Playback
    "volume": 50,
    "max_history": 5000,
    "ffplay_args": ["-nodisp", "-autoexit", "-loglevel", "quiet"],
    # Database
    "db_path": str(CONFIG_DIR / "music_history.db"),
    # Discord
    "discord_client_id": "1510266468388835328",
    "discord_rpc_enabled": True,
    # Visualizer
    "visualizer_enabled": True,
}


def _migrate_legacy() -> None:
    """Copy old project-level config and database to the new XDG location."""
    if CONFIG_FILE.exists():
        return  # new config already exists — nothing to do
    if not _LEGACY_FILE.exists():
        return  # nothing to migrate

    CONFIG_DIR.mkdir(parents=True, exist_ok=True)
    try:
        with open(_LEGACY_FILE) as f:
            old = json.load(f)

        # Migrate the database file if it lived in the old project dir.
        old_db_path = Path(old.get("db_path", ""))
        if old_db_path.parent == Path(__file__).parent and old_db_path.exists():
            new_db_path = CONFIG_DIR / "music_history.db"
            if not new_db_path.exists():
                import shutil
                shutil.copy2(str(old_db_path), str(new_db_path))
            old["db_path"] = str(new_db_path)

        save_config({**DEFAULT_CONFIG, **old})
        # Rename legacy config so we don't re-migrate every launch.
        _LEGACY_FILE.rename(_LEGACY_FILE.with_suffix(".json.migrated"))
    except (json.JSONDecodeError, OSError):
        pass


def load_config() -> dict:
    _migrate_legacy()

    if CONFIG_FILE.exists():
        try:
            with open(CONFIG_FILE) as f:
                return {**DEFAULT_CONFIG, **json.load(f)}
        except (json.JSONDecodeError, OSError):
            pass

    # First launch — create the directory and write defaults.
    CONFIG_DIR.mkdir(parents=True, exist_ok=True)
    save_config(dict(DEFAULT_CONFIG))
    return dict(DEFAULT_CONFIG)


def save_config(config: dict) -> None:
    """Merge *config* over defaults and persist to disk."""
    CONFIG_DIR.mkdir(parents=True, exist_ok=True)
    merged = {**DEFAULT_CONFIG, **config}
    with open(CONFIG_FILE, "w") as f:
        json.dump(merged, f, indent=2)


def save_volume(volume: int) -> None:
    """Persist current volume to disk and update in-memory SETTINGS."""
    volume = max(0, min(100, volume))
    SETTINGS["volume"] = volume
    save_config(dict(SETTINGS))


def save_setting(key: str, value) -> None:
    """Persist a single setting and update the in-memory SETTINGS dict."""
    SETTINGS[key] = value
    save_config(dict(SETTINGS))


def get_setting(key: str):
    """Return a setting value from the in-memory dict."""
    return SETTINGS.get(key, DEFAULT_CONFIG.get(key))


SETTINGS = load_config()