ProductDetailsViewModel.kt

@HiltViewModel
class ProductDetailsViewModel @Inject constructor(
    private val productRepository: ProductRepository,
    savedStateHandle: SavedStateHandle,
    ) : ViewModel() {

    private val _product = MutableStateFlow<Product?>(null)
    val product: Flow<Product?> = _product

    private val _name = MutableStateFlow("")
    val name: Flow<String> = _name

    private val _price = MutableStateFlow(0.0)
    val price: Flow<Double> = _price

    private val _imageUrl = MutableStateFlow("")
    val imageUrl: Flow<String> = _imageUrl

    init {
        val productId = savedStateHandle.get<String>(ProductDetailsDestination.productId)
        productId?.let {
            getProduct(productId = it)
        }
    }

    private fun getProduct(productId: String) {
        viewModelScope.launch {
           val result = productRepository.getProduct(productId).asDomainModel()
            _product.emit(result)
            _name.emit(result.name)
            _price.emit(result.price)
        }
    }

    fun onNameChange(name: String) {
        _name.value = name
    }

    fun onPriceChange(price: Double) {
        _price.value = price
    }

    fun onSaveProduct(image: ByteArray) {
        viewModelScope.launch {
            productRepository.updateProduct(
                id = _product.value?.id,
                price = _price.value,
                name = _name.value,
                imageFile = image,
                imageName = "image_${_product.value.id}",
            )
        }
    }

    fun onImageChange(url: String) {
        _imageUrl.value = url
    }

    private fun ProductDto.asDomainModel(): Product {
        return Product(
            id = this.id,
            name = this.name,
            price = this.price,
            image = this.image
        )
    }
}