from __future__ import annotations

from backend.app.api.schemas import SettingsResponse, SettingsUpdateRequest
from backend.app.db.settings_repository import SettingsRepository
from backend.app.security.path_guard import PathGuard


class SettingsService:
    def __init__(self, repository: SettingsRepository, path_guard: PathGuard):
        self._repository = repository
        self._path_guard = path_guard

    def get_settings(self) -> SettingsResponse:
        values = self._repository.get_settings()
        preferred_left = self._as_optional_str(values.get("preferred_startup_path_left"))
        preferred_right = self._as_optional_str(values.get("preferred_startup_path_right"))
        legacy_preferred = self._as_optional_str(values.get("preferred_startup_path"))
        return SettingsResponse(
            show_thumbnails=self._as_bool(values.get("show_thumbnails"), default=False),
            preferred_startup_path_left=preferred_left or legacy_preferred,
            preferred_startup_path_right=preferred_right,
        )

    def update_settings(self, request: SettingsUpdateRequest) -> SettingsResponse:
        if request.show_thumbnails is not None:
            self._repository.set_setting("show_thumbnails", "true" if request.show_thumbnails else "false")

        if request.preferred_startup_path_left is not None:
            self._set_directory_setting("preferred_startup_path_left", request.preferred_startup_path_left)

        if request.preferred_startup_path_right is not None:
            self._set_directory_setting("preferred_startup_path_right", request.preferred_startup_path_right)

        return self.get_settings()

    def _set_directory_setting(self, key: str, value: str) -> None:
        normalized = value.strip()
        if not normalized:
            self._repository.set_setting(key, "")
            return
        resolved = self._path_guard.resolve_directory_path(normalized)
        self._repository.set_setting(key, resolved.relative)

    @staticmethod
    def _as_bool(value: str | None, default: bool) -> bool:
        if value is None:
            return default
        return value.strip().lower() in {"1", "true", "yes", "on"}

    @staticmethod
    def _as_optional_str(value: str | None) -> str | None:
        if value is None:
            return None
        normalized = value.strip()
        return normalized or None