/**
 * IndexedDB storage for locale preference
 */

import { createIndexedDBHelper, type IndexedDBHelper } from './helpers/indexedDBHelper'

const DB_NAME = 'nostr_paywall_settings'
const DB_VERSION = 2 // Incremented to add locale store
const STORE_NAME = 'locale'

export type Locale = 'fr' | 'en'

class LocaleStorageService {
  private readonly dbHelper: IndexedDBHelper

  constructor() {
    this.dbHelper = createIndexedDBHelper({
      dbName: DB_NAME,
      version: DB_VERSION,
      storeName: STORE_NAME,
      keyPath: 'key',
    })
  }

  /**
   * Get locale from IndexedDB
   */
  async getLocale(): Promise<Locale | null> {
    try {
      const result = await this.dbHelper.get<{ key: string; value: Locale }>('locale')
      const locale = result?.value
      if (locale === 'fr' || locale === 'en') {
        return locale
      }
      return null
    } catch (error) {
      console.error('Error retrieving locale from IndexedDB:', error)
      return null
    }
  }

  /**
   * Save locale to IndexedDB
   */
  async saveLocale(locale: Locale): Promise<void> {
    try {
      await this.dbHelper.put({ key: 'locale', value: locale })
    } catch (error) {
      console.error('Error saving locale to IndexedDB:', error)
      throw error
    }
  }

  /**
   * Migrate locale from localStorage to IndexedDB if it exists
   */
  async migrateFromLocalStorage(): Promise<void> {
    if (typeof window === 'undefined') {
      return
    }

    try {
      const LOCALE_STORAGE_KEY = 'zapwall-locale'
      const storedLocale = window.localStorage.getItem(LOCALE_STORAGE_KEY) as Locale | null

      if (storedLocale && (storedLocale === 'fr' || storedLocale === 'en')) {
        // Check if already in IndexedDB
        const existingLocale = await this.getLocale()
        if (!existingLocale) {
          // Migrate from localStorage to IndexedDB
          await this.saveLocale(storedLocale)
          // Remove from localStorage after successful migration
          window.localStorage.removeItem(LOCALE_STORAGE_KEY)
        }
      }
    } catch (error) {
      console.error('Error migrating locale from localStorage:', error)
    }
  }
}

export const localeStorage = new LocaleStorageService()