BrowseViewModel.kt

class BrowseViewModel : ViewModel() {
    private val _products: MutableStateFlow<List<Product>> = MutableStateFlow(emptyList())
    val products: StateFlow<List<Product>> = _products.asStateFlow()

    init {
        viewModelScope.launch {
            delay(1000)
            _products.value = FakeDataSource.ALL_PRODUCTS
        }
    }

    fun add(productId: String) {
        val newProductList = _products.value.map { product ->
            if (product.id == productId) {
                return@map product.copy(quantity = product.quantity + 1)
            } else {
                return@map product
            }
        }
        _products.value = newProductList
    }
    fun remove(productId: String) {
        val newProductList = _products.value.map { product ->
            if (product.id == productId) {
                return@map product.copy(quantity = product.quantity - 1)
            } else {
                return@map product
            }
        }
        _products.value = newProductList
    }
}