import * as FileSystem from 'expo-file-system';

export interface AppSettings {
  countdownDuration: number; // in seconds
  printerIp: string;
  adminPassword: string;
  kioskModeEnabled: boolean;
}

const SETTINGS_FILE = `${FileSystem.documentDirectory}settings.json`;

const DEFAULT_SETTINGS: AppSettings = {
  countdownDuration: 3,
  printerIp: '192.168.1.100',
  adminPassword: '1234',
  kioskModeEnabled: false,
};

/**
 * Load settings from persistent storage.
 */
export async function loadSettings(): Promise<AppSettings> {
  try {
    const fileInfo = await FileSystem.getInfoAsync(SETTINGS_FILE);
    if (fileInfo.exists) {
      const content = await FileSystem.readAsStringAsync(SETTINGS_FILE);
      const parsed = JSON.parse(content);
      return { ...DEFAULT_SETTINGS, ...parsed };
    }
  } catch (e) {
    console.error('Failed to load settings, using defaults:', e);
  }
  return DEFAULT_SETTINGS;
}

/**
 * Save settings to persistent storage.
 */
export async function saveSettings(settings: AppSettings): Promise<void> {
  try {
    const content = JSON.stringify(settings, null, 2);
    await FileSystem.writeAsStringAsync(SETTINGS_FILE, content);
    console.log('Settings saved successfully:', content);
  } catch (e) {
    console.error('Failed to save settings:', e);
    throw e;
  }
}