demo_trade/ViewModels/OrderShowDialogViewModel.cs

using Avalonia.Controls;
using demo_trade.Data.RemoteData.Entity;
using demo_trade.Domain;
using demo_trade.Models;
using demo_trade.UI.Presenters;
using DynamicData;
using ReactiveUI;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Reactive;
using System.Reflection.Emit;
using System.Text;
using System.Threading.Tasks;

namespace demo_trade.ViewModels
{
    public class OrderShowDialogViewModel : ViewModelBase
    {

        private OrderClientUseCase _orderClientUseCase;

        private PickupPoint _pickupPointSelected = new();
        public PickupPoint PickupPointSelected { get => _pickupPointSelected; set => this.RaiseAndSetIfChanged(ref _pickupPointSelected, value); }

        private Models.Order? orderComplete { get; set; } = null; 
      
        private string _userName = String.Empty; 
        public string UserName{ get => _userName; set => this.RaiseAndSetIfChanged(ref _userName, value); } 

        private int _numberOrder = 0;
        public int NumberOrder { get => _numberOrder; set => this.RaiseAndSetIfChanged(ref _numberOrder, value); }

        private int _selectedPointId = 0;
        public int SelectedPointId { get => _selectedPointId; set => this.RaiseAndSetIfChanged(ref _selectedPointId, value); }

        private List<PickupPoint> _pickupPoints = new();
        public List<PickupPoint> PickupPoints { get => _pickupPoints; set => this.RaiseAndSetIfChanged(ref _pickupPoints, value); }

        private Decimal _orderSumValue  = 0;
        public Decimal OrderSumValue { get => _orderSumValue; set => this.RaiseAndSetIfChanged(ref _orderSumValue, value); }

        public ReactiveCommand<Unit, Unit> GenerateOrderCommand { get; }


        private ObservableCollection<OrderProductPresenter> _productOrderList = new();
        public ObservableCollection<OrderProductPresenter> ProductOrderList
        {
            get => _productOrderList;
            set => this.RaiseAndSetIfChanged(ref _productOrderList, value);
        }

        public OrderShowDialogViewModel( Dictionary<string, (ProductPresenter, int)> orderProducts, OrderClientUseCase orderClientUseCase, User? user = null) {

            _orderClientUseCase = orderClientUseCase;
            _numberOrder = _orderClientUseCase.GetNewOrderNumber();
            _pickupPoints = _orderClientUseCase.GetPickupPoints();
            if (user != null)
            {
                UserName = String.Format("{0} {1} {2}", user.Usersurname, user.Username, user.Userpatronymic);
            }
            GenerateOrderCommand = ReactiveCommand.Create(() => {
                string? clientName = null;
               if(!String.IsNullOrEmpty(UserName)) clientName = UserName;
                var resultOrder = _orderClientUseCase.GenerateNewOrder(PickupPointSelected, ProductOrderList.ToList(),OrderSumValue, clientName);
                if (resultOrder != null) { 
                    NumberOrder = resultOrder.Orderid + 1;
                    orderComplete = resultOrder;
                }
            });

            foreach (var item in orderProducts.Values)
            {
                ProductOrderList.Add(new OrderProductPresenter(item.Item1, item.Item2));
            }

            this.WhenAnyValue(it => it.ProductOrderList).Subscribe(it => CalculateOrderSum());
        
        }

        public void NumericChange(string ArticleProduct, int value) {
            ProductOrderList.First(it => it.ArticleNumber == ArticleProduct).ProductCount = value;
            CalculateOrderSum();
            if (value == 0)
            { 
                ProductOrderList.Remove(ProductOrderList.First(it => it.ArticleNumber == ArticleProduct));
                return;
            }

        }

        public void SaveFile(string path) {
            if (orderComplete == null) return;
           Ticket ticket = new Ticket() 
           {
               ClientName = orderComplete.OrderClient,  
               OrderID = orderComplete.Orderid, 
               OrderDate = DateOnly.FromDateTime(DateTime.Now), 
               OrderDelivery = orderComplete.Orderdeliverydate,
               Products = orderComplete.ProductList,
               PickupPointName = orderComplete.PickupPointName,
               OrderSumCost = orderComplete.OrderSumCost
           }
           ;
            ticket.GeneratePDF(path);

        }
        private void CalculateOrderSum() {
             var orderSum = ProductOrderList.Sum(product => {
                if (product.CostWithDiscount != null) return product.CostWithDiscount * product.ProductCount;
                return product.ProductCount * product.Cost;
            });
            if (orderSum != null) OrderSumValue = orderSum.Value;

        }
    }

}