//! Settings and app-config use-case implementation.
//!
//! `SettingsServiceImpl` implements [`SettingsService`] from the domain
//! layer. It is generic over `S: SettingsRepository` and `C: AppConfigRepository`,
//! delegating persistence to those adapters.
//!
//! # Flow
//!
//! Each method delegates to the appropriate injected repository with the
//! configured `base_dir`. The `update_provider` method coordinates between
//! both repositories: load app config → mutate provider map → save app config.

use std::path::PathBuf;
use tracing;

use zesdex_domain::cms::{
    AppConfig, AppConfigRepository, ProviderConfig, ServiceError, Settings,
    SettingsRepository,
};

/// Service implementation for settings and app-config operations.
///
/// Generic over `S: SettingsRepository` and `C: AppConfigRepository` so
/// the persistence layer can be swapped without changing business logic.
pub struct SettingsServiceImpl<S, C> {
    pub settings_repo: S,
    pub app_config_repo: C,
    pub base_dir: PathBuf,
}

impl<S: SettingsRepository, C: AppConfigRepository> SettingsServiceImpl<S, C> {
    /// Create a new service with the given repositories and base directory.
    pub fn new(
        settings_repo: S,
        app_config_repo: C,
        base_dir: impl Into<PathBuf>,
    ) -> Self {
        tracing::debug!("creating SettingsServiceImpl");
        Self {
            settings_repo,
            app_config_repo,
            base_dir: base_dir.into(),
        }
    }
}

impl<S: SettingsRepository, C: AppConfigRepository>
    zesdex_domain::cms::SettingsService for SettingsServiceImpl<S, C>
{
    fn load_settings(&self) -> Result<Settings, ServiceError> {
        tracing::debug!("loading settings");
        self.settings_repo
            .load(&self.base_dir)
            .map_err(ServiceError::Repository)
    }

    fn save_settings(&self, settings: &Settings) -> Result<(), ServiceError> {
        tracing::debug!("saving settings");
        self.settings_repo.save(&self.base_dir, settings)?;
        Ok(())
    }

    fn update_provider(
        &self,
        name: &str,
        config: &ProviderConfig,
    ) -> Result<(), ServiceError> {
        tracing::debug!("updating provider '{name}'");
        let mut app_config: AppConfig = self.app_config_repo.load(&self.base_dir)?;
        app_config
            .providers
            .insert(name.to_string(), config.clone());
        self.app_config_repo.save(&self.base_dir, &app_config)?;
        Ok(())
    }
}