import os
from dataclasses import dataclass
import hashlib
from pathlib import Path


def _env_bool(name: str, default: bool) -> bool:
    raw = os.getenv(name)
    if raw is None:
        return default
    normalized = raw.strip().lower()
    if normalized in {"1", "true", "yes", "on"}:
        return True
    if normalized in {"0", "false", "no", "off"}:
        return False
    return default


@dataclass(frozen=True)
class Settings:
    access_token: str
    catalog_db_path: str
    player_db_path: str
    local_library_root: str | None
    disable_auth: bool
    cache_relay_enabled: bool
    admin_username: str
    admin_password_hash: str
    secret_encryption_key: str
    cache_reconcile_interval_seconds: int
    stream_token_ttl_seconds: int
    musicfree_version_json_path: str
    musicfree_apk_path: str


def _default_admin_password_hash() -> str:
    return f"sha256${hashlib.sha256('admin'.encode('utf-8')).hexdigest()}"


def _env_int(name: str, default: int) -> int:
    raw = os.getenv(name)
    if raw is None:
        return default
    try:
        return int(raw.strip())
    except ValueError:
        return default


def _default_musicfree_release_dir() -> Path:
    project_root = Path(__file__).resolve().parents[2]
    sibling_release_dir = project_root.parent / "MusicFree" / "release"
    if sibling_release_dir.is_dir():
        return sibling_release_dir
    return project_root / "release"


def get_settings() -> Settings:
    musicfree_release_dir = Path(
        os.getenv("MUSICFREE_RELEASE_DIR", str(_default_musicfree_release_dir()))
    )
    return Settings(
        access_token=os.getenv("PUBLIC_MUSIC_ACCESS_TOKEN", "dev-token"),
        catalog_db_path=os.getenv("CATALOG_DB_PATH", "./data/catalog_read.db"),
        player_db_path=os.getenv("PLAYER_DB_PATH", "./data/player.db"),
        local_library_root=os.getenv("LOCAL_LIBRARY_ROOT"),
        disable_auth=_env_bool("MUSIC_SERVER_DISABLE_AUTH", default=False),
        cache_relay_enabled=_env_bool("MUSIC_SERVER_CACHE_RELAY_ENABLED", default=True),
        admin_username=os.getenv("MUSIC_SERVER_ADMIN_USERNAME", "admin"),
        admin_password_hash=os.getenv(
            "MUSIC_SERVER_ADMIN_PASSWORD_HASH",
            _default_admin_password_hash(),
        ),
        secret_encryption_key=os.getenv(
            "MUSIC_SERVER_SECRET_ENCRYPTION_KEY",
            "dev-secret-encryption-key",
        ),
        cache_reconcile_interval_seconds=_env_int(
            "MUSIC_SERVER_CACHE_RECONCILE_INTERVAL_SECONDS",
            600,
        ),
        stream_token_ttl_seconds=_env_int(
            "MUSIC_SERVER_STREAM_TOKEN_TTL_SECONDS",
            3600,
        ),
        musicfree_version_json_path=os.getenv(
            "MUSICFREE_VERSION_JSON",
            str(musicfree_release_dir / "version.json"),
        ),
        musicfree_apk_path=os.getenv(
            "MUSICFREE_APK_PATH",
            str(musicfree_release_dir / "MusicFree_latest_release_universal.apk"),
        ),
    )