feat(desktop): Add overview of loans to be migrated

source/Gnomeshade.Avalonia.Core/DesignTime/DesignTimeData.cs

@@ -21,6 +21,7 @@
 using Gnomeshade.Avalonia.Core.Transactions.Controls;
 using Gnomeshade.Avalonia.Core.Transactions.Links;
 using Gnomeshade.Avalonia.Core.Transactions.Loans;
+using Gnomeshade.Avalonia.Core.Transactions.Loans.Migration;
 using Gnomeshade.Avalonia.Core.Transactions.Purchases;
 using Gnomeshade.Avalonia.Core.Transactions.Transfers;
 using Gnomeshade.WebApi.Client;
@@ -217,6 +218,9 @@ public static class DesignTimeData
 	/// <summary>Gets an instance of <see cref="LicensesViewModel"/> for use during design time.</summary>
 	public static LicensesViewModel LicensesViewModel { get; } = CreateViewModel<LicensesViewModel>();
 
+	/// <summary>Gets an instance of <see cref="LoanMigrationViewModel"/> for use during design time.</summary>
+	public static LoanMigrationViewModel LoanMigrationViewModel { get; } = CreateViewModel<LoanMigrationViewModel>();
+
 	[UnconditionalSuppressMessage(
 		"Trimming",
 		"IL2026:Members annotated with 'RequiresUnreferencedCodeAttribute' require dynamic access otherwise can break functionality when trimming application code",

source/Gnomeshade.Avalonia.Core/MainWindowViewModel.cs

@@ -21,6 +21,7 @@
 using Gnomeshade.Avalonia.Core.Products;
 using Gnomeshade.Avalonia.Core.Reports;
 using Gnomeshade.Avalonia.Core.Transactions;
+using Gnomeshade.Avalonia.Core.Transactions.Loans.Migration;
 
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Options;
@@ -169,6 +170,10 @@ public void SwitchToSetup()
 	/// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
 	public Task SwitchToTransactionOverviewAsync() => SwitchTo<TransactionViewModel>();
 
+	/// <summary>Switches <see cref="ActiveView"/> to <see cref="LoanMigrationViewModel"/>.</summary>
+	/// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
+	public Task SwitchToLoanMigrationAsync() => SwitchTo<LoanMigrationViewModel>();
+
 	/// <summary>Event handler for <see cref="IClassicDesktopStyleApplicationLifetime.ShutdownRequested"/>.</summary>
 	/// <param name="sender">The object that sent the event.</param>
 	/// <param name="eventArgs">Event arguments.</param>

source/Gnomeshade.Avalonia.Core/ServiceCollectionExtensions.cs

@@ -12,6 +12,7 @@
 using Gnomeshade.Avalonia.Core.Products;
 using Gnomeshade.Avalonia.Core.Reports;
 using Gnomeshade.Avalonia.Core.Transactions;
+using Gnomeshade.Avalonia.Core.Transactions.Loans.Migration;
 
 using Microsoft.Extensions.DependencyInjection;
 
@@ -46,5 +47,6 @@ public static IServiceCollection AddViewModels(this IServiceCollection serviceCo
 		.AddSingleton<OwnerViewModel>()
 		.AddSingleton<OwnerUpsertionViewModel>()
 		.AddSingleton<AboutViewModel>()
-		.AddSingleton<LicensesViewModel>();
+		.AddSingleton<LicensesViewModel>()
+		.AddSingleton<LoanMigrationViewModel>();
 }

source/Gnomeshade.Avalonia.Core/Transactions/Loans/Migration/LoanCounterpartyComparer.cs

@@ -0,0 +1,36 @@
+// Copyright 2021 Valters Melnalksnis
+// Licensed under the GNU Affero General Public License v3.0 or later.
+// See LICENSE.txt file in the project root for full license information.
+
+using System;
+using System.Collections.Generic;
+
+using Gnomeshade.WebApi.Models.Transactions;
+
+namespace Gnomeshade.Avalonia.Core.Transactions.Loans.Migration;
+
+/// <inheritdoc />
+internal sealed class LoanCounterpartyComparer : IEqualityComparer<Loan?>
+{
+	public bool Equals(Loan? x, Loan? y)
+	{
+		if (ReferenceEquals(x, y))
+		{
+			return true;
+		}
+
+		if (ReferenceEquals(x, null) || ReferenceEquals(y, null))
+		{
+			return false;
+		}
+
+		return
+			(x.IssuingCounterpartyId == y.IssuingCounterpartyId && x.ReceivingCounterpartyId == y.ReceivingCounterpartyId) ||
+			(x.IssuingCounterpartyId == y.ReceivingCounterpartyId && x.ReceivingCounterpartyId == y.IssuingCounterpartyId);
+	}
+
+	public int GetHashCode(Loan obj)
+	{
+		return HashCode.Combine(obj.IssuingCounterpartyId, obj.ReceivingCounterpartyId);
+	}
+}

source/Gnomeshade.Avalonia.Core/Transactions/Loans/Migration/LoanMigrationRow.cs

@@ -0,0 +1,41 @@
+// Copyright 2021 Valters Melnalksnis
+// Licensed under the GNU Affero General Public License v3.0 or later.
+// See LICENSE.txt file in the project root for full license information.
+
+using System.Collections.Generic;
+
+namespace Gnomeshade.Avalonia.Core.Transactions.Loans.Migration;
+
+/// <summary>Row for displaying how a loan will look after migrating.</summary>
+public sealed class LoanMigrationRow : PropertyChangedBase
+{
+	/// <summary>Initializes a new instance of the <see cref="LoanMigrationRow"/> class.</summary>
+	/// <param name="name">The name of the loan.</param>
+	/// <param name="issuer">The issuer of the loan.</param>
+	/// <param name="receiver">The receiver of the loan.</param>
+	/// <param name="amounts">The amount of the loan payments.</param>
+	/// <param name="currency">The currency code of <paramref name="amounts"/>.</param>
+	public LoanMigrationRow(string name, string issuer, string receiver, List<decimal> amounts, string currency)
+	{
+		Name = name;
+		Issuer = issuer;
+		Receiver = receiver;
+		Amounts = amounts;
+		Currency = currency;
+	}
+
+	/// <summary>Gets the name of the loan.</summary>
+	public string Name { get; }
+
+	/// <summary>Gets the issuer of the loan.</summary>
+	public string Issuer { get; }
+
+	/// <summary>Gets the receiver of the loan.</summary>
+	public string Receiver { get; }
+
+	/// <summary>Gets the loan payment amounts.</summary>
+	public List<decimal> Amounts { get; }
+
+	/// <summary>Gets the currency code of <see cref="Amounts"/>.</summary>
+	public string Currency { get; }
+}

source/Gnomeshade.Avalonia.Core/Transactions/Loans/Migration/LoanMigrationViewModel.cs

@@ -0,0 +1,89 @@
+// Copyright 2021 Valters Melnalksnis
+// Licensed under the GNU Affero General Public License v3.0 or later.
+// See LICENSE.txt file in the project root for full license information.
+
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+
+using Gnomeshade.WebApi.Client;
+
+using NodaTime;
+
+using PropertyChanged.SourceGenerator;
+
+namespace Gnomeshade.Avalonia.Core.Transactions.Loans.Migration;
+
+/// <summary>Overview of loans to be migrated to named loans/loan payments.</summary>
+public sealed partial class LoanMigrationViewModel : ViewModelBase
+{
+	private readonly IGnomeshadeClient _gnomeshadeClient;
+
+	/// <summary>Gets a collection of all current loans.</summary>
+	[Notify(Setter.Private)]
+	private List<LoanOverview> _loans = [];
+
+	/// <summary>Gets a collection of all loan payments that will be created.</summary>
+	[Notify(Setter.Private)]
+	private List<LoanMigrationRow> _migratedLoans = [];
+
+	/// <summary>Initializes a new instance of the <see cref="LoanMigrationViewModel"/> class.</summary>
+	/// <param name="activityService">Service for indicating the activity of the application to the user.</param>
+	/// <param name="gnomeshadeClient">A strongly typed API client.</param>
+	public LoanMigrationViewModel(IActivityService activityService, IGnomeshadeClient gnomeshadeClient)
+		: base(activityService)
+	{
+		_gnomeshadeClient = gnomeshadeClient;
+	}
+
+	/// <inheritdoc />
+	protected override async Task Refresh()
+	{
+		var loans = await _gnomeshadeClient.GetLoansAsync();
+		var counterparties = await _gnomeshadeClient.GetCounterpartiesAsync();
+		var transactions = await _gnomeshadeClient.GetDetailedTransactionsAsync(new(Instant.MinValue, Instant.MaxValue));
+		var currencies = await _gnomeshadeClient.GetCurrenciesAsync();
+
+		MigratedLoans = loans
+			.OrderBy(loan =>
+			{
+				var transaction = transactions.Single(transaction => transaction.Id == loan.TransactionId);
+				return transaction.ValuedAt ?? transaction.BookedAt;
+			})
+			.GroupBy(loan => loan, new LoanCounterpartyComparer())
+			.Select(grouping =>
+			{
+				var counterparty1 = counterparties.Single(counterparty => counterparty.Id == grouping.Key.IssuingCounterpartyId);
+				var counterparty2 = counterparties.Single(counterparty => counterparty.Id == grouping.Key.ReceivingCounterpartyId);
+				return (counterparty1, counterparty2, grouping.ToArray());
+			})
+			.SelectMany(loanTuple =>
+			{
+				var issuer = loanTuple.Item3.First().IssuingCounterpartyId == loanTuple.counterparty1.Id
+					? loanTuple.counterparty1
+					: loanTuple.counterparty2;
+
+				var receiver = loanTuple.counterparty1 == issuer
+					? loanTuple.counterparty2
+					: loanTuple.counterparty1;
+
+				return loanTuple.Item3.GroupBy(loan => loan.CurrencyId).Select(grouping =>
+				{
+					var currency = currencies.Single(currency => currency.Id == grouping.Key);
+					var name = $"{issuer.Name} loan to {receiver.Name} ({currency.AlphabeticCode})";
+					return new LoanMigrationRow(name, issuer.Name, receiver.Name, grouping.Select(loan => loan.Amount).ToList(), currency.AlphabeticCode);
+				});
+			})
+			.ToList();
+
+		Loans = transactions
+			.SelectMany(transaction => transaction.Loans)
+			.Select(loan => new LoanOverview(
+				loan.Id,
+				counterparties.Single(counterparty => counterparty.Id == loan.IssuingCounterpartyId).Name,
+				counterparties.Single(counterparty => counterparty.Id == loan.ReceivingCounterpartyId).Name,
+				loan.Amount,
+				currencies.Single(currency => currency.Id == loan.CurrencyId).AlphabeticCode))
+			.ToList();
+	}
+}

source/Gnomeshade.Desktop/Views/MainWindow.axaml

@@ -68,6 +68,9 @@
 					<MenuItem
 						x:Name="Transactions" Header="_Overview"
 						Command="{Binding SwitchToTransactionOverviewAsync}" />
+					<MenuItem
+						x:Name="LoanMigration" Header="Loan Migration"
+						Command="{Binding SwitchToLoanMigrationAsync}" />
 					<MenuItem
 						x:Name="Import" Header="_Import"
 						Command="{Binding SwitchToImportAsync}" />

source/Gnomeshade.Desktop/Views/Transactions/Loans/Migration/LoanMigrationView.axaml

@@ -0,0 +1,100 @@
+<UserControl
+	xmlns="https://github.com/avaloniaui"
+	xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+	xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+	xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+	xmlns:dd="clr-namespace:Gnomeshade.Avalonia.Core.DesignTime;assembly=Gnomeshade.Avalonia.Core"
+	xmlns:migration="clr-namespace:Gnomeshade.Avalonia.Core.Transactions.Loans.Migration;assembly=Gnomeshade.Avalonia.Core"
+	xmlns:loans="clr-namespace:Gnomeshade.Avalonia.Core.Transactions.Loans;assembly=Gnomeshade.Avalonia.Core"
+	xmlns:system="clr-namespace:System;assembly=System.Runtime"
+	mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
+	d:DataContext="{x:Static dd:DesignTimeData.LoanMigrationViewModel}"
+	x:Class="Gnomeshade.Desktop.Views.Transactions.Loans.Migration.LoanMigrationView"
+	x:DataType="migration:LoanMigrationViewModel">
+
+	<Grid ColumnDefinitions="Auto,Auto,Auto" RowDefinitions="Auto,*">
+
+		<TextBlock Grid.Column="0" Grid.Row="0" Text="Legacy loans" HorizontalAlignment="Center"/>
+		<DataGrid
+			Grid.Column="0" Grid.Row="1"
+			VerticalAlignment="Stretch"
+			ItemsSource="{Binding Loans, Mode=TwoWay}"
+			AutoGenerateColumns="False" IsReadOnly="False"
+			CanUserReorderColumns="True" CanUserResizeColumns="True" CanUserSortColumns="True">
+			<DataGrid.Columns>
+				<DataGridTextColumn
+					x:DataType="loans:LoanOverview"
+					Header="Issuer" IsReadOnly="True"
+					Binding="{Binding IssuingCounterparty, Mode=OneWay}" />
+				<DataGridTextColumn
+					x:DataType="loans:LoanOverview"
+					Header="Receiver" IsReadOnly="True"
+					Binding="{Binding ReceivingCounterparty, Mode=OneWay}" />
+				<DataGridTextColumn
+					x:DataType="loans:LoanOverview"
+					Header="Amount" IsReadOnly="True"
+					Binding="{Binding Amount, Mode=OneWay, StringFormat=\{0:N2\}}" />
+				<DataGridTextColumn
+					x:DataType="loans:LoanOverview"
+					Header="Currency" IsReadOnly="True"
+					Binding="{Binding Currency, Mode=OneWay}" />
+			</DataGrid.Columns>
+		</DataGrid>
+
+		<TextBlock Grid.Column="1" Grid.Row="0" Text="Loans with payments" HorizontalAlignment="Center"/>
+		<DataGrid
+			Grid.Column="1" Grid.Row="1"
+			VerticalScrollBarVisibility="Visible" HorizontalScrollBarVisibility="Visible"
+			ItemsSource="{Binding MigratedLoans, Mode=TwoWay}"
+			AutoGenerateColumns="False" IsReadOnly="False"
+			CanUserReorderColumns="True" CanUserResizeColumns="True" CanUserSortColumns="True">
+			<DataGrid.Columns>
+				<DataGridTemplateColumn Header="Name" IsReadOnly="True">
+					<DataTemplate x:DataType="migration:LoanMigrationRow">
+						<TextBlock
+							HorizontalAlignment="Right" VerticalAlignment="Top" Margin="5 0"
+							Text="{Binding Name, Mode=OneWay}" />
+					</DataTemplate>
+				</DataGridTemplateColumn>
+				<DataGridTemplateColumn Header="Issuer" IsReadOnly="True">
+					<DataTemplate x:DataType="migration:LoanMigrationRow">
+						<TextBlock
+							HorizontalAlignment="Right" VerticalAlignment="Top" Margin="5 0"
+							Text="{Binding Issuer, Mode=OneWay}" />
+					</DataTemplate>
+				</DataGridTemplateColumn>
+				<DataGridTemplateColumn Header="Receiver" IsReadOnly="True">
+					<DataTemplate x:DataType="migration:LoanMigrationRow">
+						<TextBlock
+							HorizontalAlignment="Right" VerticalAlignment="Top" Margin="5 0"
+							Text="{Binding Receiver, Mode=OneWay}" />
+					</DataTemplate>
+				</DataGridTemplateColumn>
+				<DataGridTemplateColumn Header="Currency" IsReadOnly="True">
+					<DataTemplate x:DataType="migration:LoanMigrationRow">
+						<TextBlock
+							HorizontalAlignment="Right" VerticalAlignment="Top" Margin="5 0"
+							Text="{Binding Currency, Mode=OneWay}" />
+					</DataTemplate>
+				</DataGridTemplateColumn>
+				<DataGridTemplateColumn Header="Payments" IsReadOnly="True">
+					<DataTemplate x:DataType="migration:LoanMigrationRow">
+						<ItemsControl ItemsSource="{Binding Amounts}">
+							<ItemsControl.ItemTemplate>
+								<DataTemplate x:DataType="system:Decimal">
+									<TextBlock
+										HorizontalAlignment="Right" VerticalAlignment="Top" Margin="5 0"
+										Text="{Binding ., Mode=OneWay, StringFormat=\{0:N2\}}" />
+								</DataTemplate>
+							</ItemsControl.ItemTemplate>
+						</ItemsControl>
+
+					</DataTemplate>
+				</DataGridTemplateColumn>
+			</DataGrid.Columns>
+		</DataGrid>
+
+		<!-- <UserControl Grid.Column="2" Content="{Binding Details}" /> -->
+	</Grid>
+
+</UserControl>

source/Gnomeshade.Desktop/Views/Transactions/Loans/Migration/LoanMigrationView.axaml.cs

@@ -0,0 +1,17 @@
+// Copyright 2021 Valters Melnalksnis
+// Licensed under the GNU Affero General Public License v3.0 or later.
+// See LICENSE.txt file in the project root for full license information.
+
+using Avalonia.Controls;
+
+using Gnomeshade.Avalonia.Core;
+using Gnomeshade.Avalonia.Core.Transactions.Loans.Migration;
+
+namespace Gnomeshade.Desktop.Views.Transactions.Loans.Migration;
+
+/// <inheritdoc cref="LoanMigrationViewModel" />
+public sealed partial class LoanMigrationView : UserControl, IView<LoanMigrationView, LoanMigrationViewModel>
+{
+	/// <summary>Initializes a new instance of the <see cref="LoanMigrationView"/> class.</summary>
+	public LoanMigrationView() => InitializeComponent();
+}