Clean Architecture və Repository pattern

// DOMAIN — təmiz Kotlin, Android importu yoxdur
data class Account(val id: String, val balance: BigDecimal)

interface AccountRepository {
    suspend fun getAccounts(): List<Account>
    fun observeAccounts(): Flow<List<Account>>
}

class GetAccountsUseCase(private val repo: AccountRepository) {
    suspend operator fun invoke(): List<Account> =
        repo.getAccounts().sortedByDescending { it.balance }
}

// DATA — Retrofit/Room burada yaşayır
class AccountRepositoryImpl @Inject constructor(
    private val api: AccountApi,
    private val dao: AccountDao
) : AccountRepository {
    override suspend fun getAccounts(): List<Account> {
        val remote = api.fetchAccounts()          // List<AccountDto>
        dao.upsertAll(remote.map { it.toEntity() })
        return dao.getAll().map { it.toDomain() }  // DB — single source of truth
    }
    override fun observeAccounts() = dao.observeAll().map { list -> list.map { it.toDomain() } }
}