Changed version number to conform to dotnet rules.

Add API key management.

.gitignore

@@ -0,0 +1,13 @@
+/PcgsInvUi/[Bb]in/
+/PcgsInvUi/[Oo]bj/
+[Oo]bj/
+[Bb]in/
+ALL_BUILD.vcxproj
+ALL_BUILD.vcxproj.filters
+ZERO_CHECK.vcxproj
+ZERO_CHECK.vcxproj.filters
+CMakeCache.txt
+CMakeFiles/
+.idea/
+cmake_install.cmake
+coin_collection

.idea/.idea.pcgs-inv/.idea/.gitignore

@@ -1,13 +0,0 @@
-# Default ignored files
-/shelf/
-/workspace.xml
-# Rider ignored files
-/.idea.pcgs-inv.iml
-/contentModel.xml
-/modules.xml
-/projectSettingsUpdater.xml
-# Editor-based HTTP Client requests
-/httpRequests/
-# Datasource local storage ignored files
-/dataSources/
-/dataSources.local.xml

.idea/.idea.pcgs-inv/.idea/avalonia.xml

@@ -1,16 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="AvaloniaProject">
-    <option name="projectPerEditor">
-      <map>
-        <entry key="PcgsInvUi/App.axaml" value="PcgsInvUi/PcgsInvUi.csproj" />
-        <entry key="PcgsInvUi/Views/CoinListView.axaml" value="PcgsInvUi/PcgsInvUi.csproj" />
-        <entry key="PcgsInvUi/Views/DeleteWindow.axaml" value="PcgsInvUi/PcgsInvUi.csproj" />
-        <entry key="PcgsInvUi/Views/MainWindow.axaml" value="PcgsInvUi/PcgsInvUi.csproj" />
-        <entry key="PcgsInvUi/Views/MainWindowOld.axaml" value="PcgsInvUi/PcgsInvUi.csproj" />
-        <entry key="PcgsInvUi/Views/NewControl.axaml" value="PcgsInvUi/PcgsInvUi.csproj" />
-        <entry key="PcgsInvUi/Views/NewView.axaml" value="PcgsInvUi/PcgsInvUi.csproj" />
-      </map>
-    </option>
-  </component>
-</project>

.idea/.idea.pcgs-inv/.idea/discord.xml

@@ -1,7 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="DiscordProjectSettings">
-    <option name="show" value="PROJECT_FILES" />
-    <option name="description" value="" />
-  </component>
-</project>

.idea/.idea.pcgs-inv/.idea/encodings.xml

@@ -1,4 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="Encoding" addBOMForNewFiles="with BOM under Windows, with no BOM otherwise" />
-</project>

.idea/.idea.pcgs-inv/.idea/indexLayout.xml

@@ -1,8 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="UserContentModel">
-    <attachedFolders />
-    <explicitIncludes />
-    <explicitExcludes />
-  </component>
-</project>

CMakeLists.txt

@@ -0,0 +1,5 @@
+cmake_minimum_required(VERSION 3.25)
+
+project("PcgsInvUi" CSharp)
+
+add_subdirectory(PcgsInvUi)

PcgsInvUi/App.axaml

@@ -2,13 +2,14 @@
              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
              x:Class="PcgsInvUi.App"
              xmlns:local="using:PcgsInvUi"
-             RequestedThemeVariant="Dark">
+             xmlns:pcgsInvUi="clr-namespace:PcgsInvUi"
-             <!-- "Default" ThemeVariant follows system theme variant. "Dark" or "Light" are other available options. -->
+             RequestedThemeVariant="Light">
+    <!-- "Default" ThemeVariant follows system theme variant. "Dark" or "Light" are other available options. -->
 
     <Application.DataTemplates>
-        <local:ViewLocator/>
+        <pcgsInvUi:ViewLocator />
     </Application.DataTemplates>
-  
+
     <Application.Styles>
         <FluentTheme />
         <StyleInclude Source="avares://Avalonia.Controls.DataGrid/Themes/Fluent.xaml" />

PcgsInvUi/App.axaml.cs

@@ -1,32 +1,30 @@
 using Avalonia;
 using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Markup.Xaml;
+using PcgsInvUi.Services;
 using PcgsInvUi.ViewModels;
 using PcgsInvUi.Views;
 
 namespace PcgsInvUi;
 
-public partial class App : Application
+public partial class App : Application {
-{
+    public override void Initialize() {
-    public override void Initialize()
-    {
         AvaloniaXamlLoader.Load(this);
     }
 
-    public override void OnFrameworkInitializationCompleted()
+    public override void OnFrameworkInitializationCompleted() {
-    {
         base.OnFrameworkInitializationCompleted();
-        
+        if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop) {
-        if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop)
+            var coins = new CoinDatabase();
-        {
+            desktop.MainWindow = new MainWindow {
-            var coins = new Services.CoinCollection();
-            
-            desktop.MainWindow = new MainWindow
-            {
                 DataContext = new MainWindowViewModel(coins),
             };
+            
+            // Allow the application to save the database when it exits.
+            desktop.Exit += (sender, args) => {
+                coins.UpdateCollection("CollectionTable");
+            };
         }
-
         base.OnFrameworkInitializationCompleted();
     }
-}
+}

PcgsInvUi/CMakeLists.txt

@@ -0,0 +1,47 @@
+cmake_minimum_required(VERSION 3.25)
+
+project(PcgsInvUi LANGUAGES CSharp)
+
+include(CSharpUtilities)
+
+add_executable(PcgsInvUi
+  App.axaml.cs
+  Program.cs
+  ViewLocator.cs
+  App.axaml
+  app.manifest
+  Models/Coin.cs
+  Services/CoinCollection.cs
+  Services/CoinDatabase.cs
+  Services/PcgsClient.cs
+  ViewModels/CoinListViewModel.cs
+  ViewModels/DeleteWindowViewModel.cs
+  ViewModels/EditViewModel.cs
+  ViewModels/ErrorWindowViewModel.cs
+  ViewModels/FindWindowViewModel.cs
+  ViewModels/MainWindowViewModel.cs
+  ViewModels/NewViewModel.cs
+  ViewModels/ViewModelBase.cs
+  Views/DeleteWindow.axaml
+  Views/DeleteWindow.axaml.cs
+  Views/ErrorWindow.axaml
+  Views/ErrorWindow.axaml.cs
+  Views/FindWindow.axaml
+  Views/FindWindow.axaml.cs
+  Views/MainWindow.axaml
+  Views/MainWindow.axaml.cs
+  Views/NewView.axaml
+  Views/NewView.axaml.cs
+)
+
+# Set the .NET Framework version for the executable.
+set_property(TARGET PcgsInvUi PROPERTY VS_DOTNET_TARGET_FRAMEWORK_VERSION "v4.7.2")
+# Set the executable to be 64-bit.
+set_property(TARGET PcgsInvUi PROPERTY WIN64_EXECUTABLE TRUE)
+# Set the C# language version (defaults to 3.0)
+set(CMAKE_CSharp_FLAGS "/langversion:latest")
+
+# Add the .NET reference libraries as dependencies.
+set_property(TARGET PcgsInvUi PROPERTY VS_DOTNET_REFERENCES
+  "Microsoft.CSharp"
+)

PcgsInvUi/Models/Coin.cs

@@ -1,135 +1,165 @@
-using System;
+using ReactiveUI;
-using ReactiveUI;
 
 namespace PcgsInvUi.Models;
 
-public class Coin : ReactiveObject
+public class Coin : ReactiveObject {
-{
+    public string PCGSNo {
-    public int PcgsNumber
+        get => _pcgsNo;
-    {
+        set => this.RaiseAndSetIfChanged(ref _pcgsNo, value);
-        get => _pcgsNumber;
-        set => this.RaiseAndSetIfChanged(ref _pcgsNumber, value);
     }
-    private int _pcgsNumber;
 
-    public string Name
+    private string _pcgsNo;
-    {
+
+    public string Name {
         get => _name;
         set => this.RaiseAndSetIfChanged(ref _name, value);
     }
+
     private string _name;
 
-    public int Year
+    public int Year {
-    {
         get => _year;
         set => this.RaiseAndSetIfChanged(ref _year, value);
     }
+
     private int _year;
 
-    public string Denomination
+    public string Denomination {
-    {
         get => _denomination;
         set => this.RaiseAndSetIfChanged(ref _denomination, value);
     }
+
     private string _denomination;
 
-    public string MintMark
+    public string MintMark {
-    {
         get => _mintMark;
         set => this.RaiseAndSetIfChanged(ref _mintMark, value);
     }
+
     private string _mintMark;
 
-    public string Grade
+    public string Grade {
-    {
         get => _grade;
         set => this.RaiseAndSetIfChanged(ref _grade, value);
     }
+
     private string _grade;
 
-    public double PriceGuideValue
+    public double PriceGuideValue {
-    {
         get => _priceGuideValue;
-        set => this.RaiseAndSetIfChanged(ref _priceGuideValue, value);
+        set {
+            TotalPrice = value * Quantity;
+            this.RaiseAndSetIfChanged(ref _priceGuideValue, value);
+        }
     }
+
     private double _priceGuideValue;
 
-    public string CoinFactsLink
+    public string CoinFactsLink {
-    {
         get => _coinFactsLink;
         set => this.RaiseAndSetIfChanged(ref _coinFactsLink, value);
     }
+
     private string _coinFactsLink;
 
-    public string MajorVariety
+    public string MajorVariety {
-    {
         get => _majorVariety;
         set => this.RaiseAndSetIfChanged(ref _majorVariety, value);
     }
+
     private string _majorVariety;
 
-    public string MinorVariety
+    public string MinorVariety {
-    {
         get => _minorVariety;
         set => this.RaiseAndSetIfChanged(ref _minorVariety, value);
     }
+
     private string _minorVariety;
 
-    public string DieVariety
+    public string DieVariety {
-    {
         get => _dieVariety;
         set => this.RaiseAndSetIfChanged(ref _dieVariety, value);
     }
+
     private string _dieVariety;
 
-    public string Series
+    public string SeriesName {
-    {
+        get => _seriesName;
-        get => _series;
+        set => this.RaiseAndSetIfChanged(ref _seriesName, value);
-        set => this.RaiseAndSetIfChanged(ref _series, value);
     }
-    private string _series;
 
-    public string Category
+    private string _seriesName;
-    {
+
+    public string Category {
         get => _category;
         set => this.RaiseAndSetIfChanged(ref _category, value);
     }
+
     private string _category;
 
-    public string Designation
+    public string Designation {
-    {
         get => _designation;
         set => this.RaiseAndSetIfChanged(ref _designation, value);
     }
+
     private string _designation;
 
-    public int CertificateNumber
+    public int CertificateNumber {
-    {
         get => _certificateNumber;
         set => this.RaiseAndSetIfChanged(ref _certificateNumber, value);
     }
+
     private int _certificateNumber;
 
-    public int Quantity
+    public int Quantity {
-    {
         get => _quantity;
-        set => this.RaiseAndSetIfChanged(ref _quantity, value);
+        set {
+            TotalPrice = value * PriceGuideValue;
+            this.RaiseAndSetIfChanged(ref _quantity, value);
+        }
     }
-    private int _quantity;
-    
-    public double TotalPrice => Quantity * PriceGuideValue;
 
-    public double PaidFor
+    private int _quantity;
-    {
+
+    public double TotalPrice {
+        get => _totalPrice;
+        set => this.RaiseAndSetIfChanged(ref _totalPrice, value);
+    }
+
+    private double _totalPrice;
+
+    public double PaidFor {
         get => _paidFor;
         set => this.RaiseAndSetIfChanged(ref _paidFor, value);
     }
+
     private double _paidFor;
 
-    public String Notes
+    public string Notes {
-    {
         get => _notes;
         set => this.RaiseAndSetIfChanged(ref _notes, value);
     }
+
     private string _notes;
+
+    public Coin() {
+        PCGSNo = "";
+        Name = "";
+        Year = 0;
+        Denomination = "";
+        MintMark = "";
+        Grade = "";
+        PriceGuideValue = 0;
+        CoinFactsLink = "";
+        MajorVariety = "";
+        MinorVariety = "";
+        DieVariety = "";
+        SeriesName = "";
+        Category = "";
+        Designation = "";
+        CertificateNumber = 0;
+        Quantity = 0;
+        PaidFor = 0;
+        Notes = "";
+    }
 }

PcgsInvUi/PcgsInvUi.csproj

@@ -1,26 +1,95 @@
 <Project Sdk="Microsoft.NET.Sdk">
-  <PropertyGroup>
+    <PropertyGroup>
-    <OutputType>WinExe</OutputType>
+        <OutputType>WinExe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+        <TargetFramework>net6.0</TargetFramework>
-    <Nullable>enable</Nullable>
+        <Nullable>enable</Nullable>
-    <BuiltInComInteropSupport>true</BuiltInComInteropSupport>
+        <BuiltInComInteropSupport>true</BuiltInComInteropSupport>
-    <ApplicationManifest>app.manifest</ApplicationManifest>
+        <ApplicationManifest>app.manifest</ApplicationManifest>
-    <AvaloniaUseCompiledBindingsByDefault>true</AvaloniaUseCompiledBindingsByDefault>
+        <AvaloniaUseCompiledBindingsByDefault>true</AvaloniaUseCompiledBindingsByDefault>
-  </PropertyGroup>
+        <Company>BobdaFett</Company>
+        <AssemblyVersion>0.0.5</AssemblyVersion>
+    </PropertyGroup>
 
-  <ItemGroup>
+    <ItemGroup>
-    <AvaloniaResource Include="Assets\**" />
+        <AvaloniaResource Include="Assets\**"/>
-  </ItemGroup>
+        <AvaloniaResource Remove="obj\**"/>
+    </ItemGroup>
 
 
-  <ItemGroup>
+    <ItemGroup>
-    <PackageReference Include="Avalonia" Version="11.0.2" />
+        <PackageReference Include="Avalonia" Version="11.0.5" />
-    <PackageReference Include="Avalonia.Desktop" Version="11.0.2" />
+        <PackageReference Include="Avalonia.Controls.DataGrid" Version="11.0.5" />
-    <PackageReference Include="Avalonia.Themes.Fluent" Version="11.0.2" />
+        <PackageReference Include="Avalonia.Desktop" Version="11.0.5" />
-    <PackageReference Include="Avalonia.Fonts.Inter" Version="11.0.2" />
+        <PackageReference Include="Avalonia.Themes.Fluent" Version="11.0.5" />
-    <!--Condition below is needed to remove Avalonia.Diagnostics package from build output in Release configuration.-->
+        <PackageReference Include="Avalonia.Fonts.Inter" Version="11.0.5" />
-    <PackageReference Condition="'$(Configuration)' == 'Debug'" Include="Avalonia.Diagnostics" Version="11.0.2" />
+        <!--Condition below is needed to remove Avalonia.Diagnostics package from build output in Release configuration.-->
-    <PackageReference Include="Avalonia.ReactiveUI" Version="11.0.2" />
+        <PackageReference Condition="'$(Configuration)' == 'Debug'" Include="Avalonia.Diagnostics" Version="11.0.5" />
-    <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
+        <PackageReference Include="Avalonia.ReactiveUI" Version="11.0.5" />
-  </ItemGroup>
+        <PackageReference Include="Newtonsoft.Json" Version="13.0.3"/>
+        <PackageReference Include="System.Data.SQLite" Version="1.0.118" />
+    </ItemGroup>
+
+
+    <ItemGroup>
+        <Content Include="obj\Debug\net6.0\apphost.exe"/>
+        <Content Include="obj\Debug\net6.0\Avalonia\original.dll"/>
+        <Content Include="obj\Debug\net6.0\Avalonia\original.pdb"/>
+        <Content Include="obj\Debug\net6.0\Avalonia\original.ref.dll"/>
+        <Content Include="obj\Debug\net6.0\Avalonia\references"/>
+        <Content Include="obj\Debug\net6.0\Avalonia\resources"/>
+        <Content Include="obj\Debug\net6.0\Avalonia\Resources.Inputs.cache"/>
+        <Content Include="obj\Debug\net6.0\PcgsInvUi.AssemblyInfoInputs.cache"/>
+        <Content Include="obj\Debug\net6.0\PcgsInvUi.assets.cache"/>
+        <Content Include="obj\Debug\net6.0\PcgsInvUi.csproj.AssemblyReference.cache"/>
+        <Content Include="obj\Debug\net6.0\PcgsInvUi.csproj.CopyComplete"/>
+        <Content Include="obj\Debug\net6.0\PcgsInvUi.csproj.CoreCompileInputs.cache"/>
+        <Content Include="obj\Debug\net6.0\PcgsInvUi.csproj.FileListAbsolute.txt"/>
+        <Content Include="obj\Debug\net6.0\PcgsInvUi.dll"/>
+        <Content Include="obj\Debug\net6.0\PcgsInvUi.GeneratedMSBuildEditorConfig.editorconfig"/>
+        <Content Include="obj\Debug\net6.0\PcgsInvUi.genruntimeconfig.cache"/>
+        <Content Include="obj\Debug\net6.0\PcgsInvUi.pdb"/>
+        <Content Include="obj\Debug\net6.0\refint\PcgsInvUi.dll"/>
+        <Content Include="obj\Debug\net6.0\ref\PcgsInvUi.dll"/>
+        <Content Include="obj\PcgsInvUi.csproj.nuget.dgspec.json"/>
+        <Content Include="obj\PcgsInvUi.csproj.nuget.g.props"/>
+        <Content Include="obj\PcgsInvUi.csproj.nuget.g.targets"/>
+        <Content Include="obj\project.assets.json"/>
+        <Content Include="obj\project.nuget.cache"/>
+        <Content Include="obj\project.packagespec.json"/>
+        <Content Include="obj\rider.project.model.nuget.info"/>
+        <Content Include="obj\rider.project.restore.info"/>
+    </ItemGroup>
+
+
+    <ItemGroup>
+        <Compile Include="obj\Debug\net6.0\.NETCoreApp,Version=v6.0.AssemblyAttributes.cs"/>
+        <Compile Include="obj\Debug\net6.0\PcgsInvUi.AssemblyInfo.cs"/>
+        <Compile Remove="obj\**"/>
+        <Compile Remove="Services\CoinCollection.cs" />
+    </ItemGroup>
+
+
+    <ItemGroup>
+        <AvaloniaXaml Remove="obj\**"/>
+    </ItemGroup>
+
+
+    <ItemGroup>
+        <EmbeddedResource Remove="obj\**"/>
+    </ItemGroup>
+
+
+    <ItemGroup>
+        <AdditionalFiles Remove="obj\**"/>
+    </ItemGroup>
+
+
+    <ItemGroup>
+        <None Remove="obj\**"/>
+    </ItemGroup>
+
+
+    <ItemGroup>
+      <Reference Include="System.Data" />
+    </ItemGroup>
 </Project>

PcgsInvUi/Program.cs

@@ -1,17 +1,16 @@
 using Avalonia;
 using Avalonia.ReactiveUI;
 using System;
+using PcgsInvUi.ViewModels;
 
 namespace PcgsInvUi;
 
-class Program
+class Program {
-{
     // Initialization code. Don't use any Avalonia, third-party APIs or any
     // SynchronizationContext-reliant code before AppMain is called: things aren't initialized
     // yet and stuff might break.
     [STAThread]
-    public static void Main(string[] args) => BuildAvaloniaApp()
+    public static void Main(string[] args) => BuildAvaloniaApp().StartWithClassicDesktopLifetime(args);
-        .StartWithClassicDesktopLifetime(args);
 
     // Avalonia configuration, don't remove; also used by visual designer.
     public static AppBuilder BuildAvaloniaApp()
@@ -20,4 +19,4 @@ class Program
             .WithInterFont()
             .LogToTrace()
             .UseReactiveUI();
-}
+}

PcgsInvUi/Services/CoinCollection.cs

@@ -1,14 +0,0 @@
-using System.Collections.Generic;
-using PcgsInvUi.Models;
-
-namespace PcgsInvUi.Services;
-
-public class CoinCollection
-{
-    public IEnumerable<Coin> GetItems() => new[]
-    {
-        new Coin(),
-        new Coin(),
-        new Coin(),
-    };
-}

PcgsInvUi/Services/CoinDatabase.cs

@@ -0,0 +1,446 @@
+using System;
+using System.Collections.ObjectModel;
+using System.Data.SQLite;
+using System.Threading.Tasks;
+using PcgsInvUi.Models;
+
+namespace PcgsInvUi.Services;
+
+public class CoinDatabase {
+    public SQLiteConnection Connection { get; set; }
+    private Boolean IsConnected { get; set; }
+    public ObservableCollection<Coin> Collection { get; set; }
+    public Boolean IsClientConnected { get; set; }
+
+    private PcgsClient? _pcgsClient;
+    
+    /// <summary>
+    /// Creates and initilizes a new instance of the CoinDatabase.
+    /// Must call TryInitApiClient() after creating a new instance.
+    /// </summary>
+    public CoinDatabase() {
+        // Create a connection to SQLite
+        Connection = CreateConnection();
+        // Create a base table.
+        CreateCollection("CollectionTable");
+        CreateApiTable();
+        Console.WriteLine("Connected to database.");
+        Collection = new ObservableCollection<Coin>();
+        GetCollection("CollectionTable");
+        Console.WriteLine("Got collection.");
+    }
+
+    /// <summary>
+    /// Destructor. Currently not used, due to the strange nature of desktop applications.
+    /// </summary>
+    ~CoinDatabase() {
+        Console.WriteLine("Destructor called, saving collection.");
+        // Save collection.
+        UpdateCollection("CollectionTable");
+        // Close the connection.
+        Connection.Close();
+    }
+    
+    /// <summary>
+    /// Attempts to intitialize the API client by selecting the API key from the database.
+    /// </summary>
+    /// <returns>True if the API key was found, false otherwise.</returns>
+    public async Task<bool> TryInitApiClient() {
+        Console.Write("Attempting to initialize API client... ");
+        SQLiteCommand cmd = Connection.CreateCommand();
+        cmd.CommandText = "SELECT API_KEY FROM ApiTable";
+
+        using (var reader = cmd.ExecuteReader()) {
+            if (reader.Read()) {
+                var apiKey = reader.GetString(0);
+                _pcgsClient = await PcgsClient.CreateClient(apiKey);
+
+                // Check that the client is valid.
+                if (_pcgsClient is null) {
+                    IsClientConnected = false;
+                    Console.WriteLine("Failed. API key was invalid.");
+                    return IsClientConnected;
+                }
+
+                IsClientConnected = true;
+                Console.WriteLine("Done! API key was found from database.");
+            }
+            else {
+                IsClientConnected = false;
+                Console.WriteLine("Failed. API key not found.");
+            }
+        }
+        return IsClientConnected;
+    }
+
+    /// <summary>
+    /// Atttempts to initialize the PCGS API client.
+    /// </summary>
+    /// <param name=apiKey>The API key to verify.</param>
+    /// <returns>A Task with a return value that returns true if the client intializes properly.</returns>
+    public async Task<bool> TryInitApiClient(string apiKey) {
+        Console.Write("Attempting to initialize API client with key param... ");
+        _pcgsClient = await PcgsClient.CreateClient(apiKey);
+        // Check if the API key is valid and if it is, then add to the database.
+        if (_pcgsClient is null) {
+            IsClientConnected = false;
+            Console.WriteLine("Failed. API key was invalid.");
+            return IsClientConnected;
+        }
+
+        var cmd = Connection.CreateCommand();
+        cmd.CommandText = $"INSERT INTO ApiTable (API_KEY, REQUESTS_REMAINING) VALUES (\"{apiKey}\", 1000)";
+        await cmd.ExecuteNonQueryAsync();
+
+        IsClientConnected = true;
+        Console.WriteLine("Done! API key was added to database.");
+        return IsClientConnected;
+    }
+
+    /// <summary>
+    /// Gets the collection from the database and stores it in the Collection property.
+    /// Creates the collection table if it does not exist already.
+    /// </summary>
+    /// <returns>The SQLiteConnection that corresponds to the connected database.</returns>
+    private SQLiteConnection CreateConnection() {
+        // Check if database exists.
+        if (!System.IO.File.Exists("coin_collection")) {
+            // If not, create the database.
+            Console.Write("Creating database... ");
+            SQLiteConnection.CreateFile("coin_collection.sqlite");
+            Console.WriteLine("Done.");
+        }
+        
+        // Create a connection to the database.
+        SQLiteConnection connection =
+            new SQLiteConnection("DataSource=coin_collection");
+        
+        // Open the connection.
+        try {
+            connection.Open();
+            IsConnected = true;
+        }
+        catch (Exception e) {
+            Console.WriteLine(e.Message);
+        }
+
+        return connection;
+    }
+
+    /// <summary>
+    /// Creates the table that stores the API key and the number of requests remaining.
+    /// </summary>
+    public void CreateApiTable() {
+        // Create a table to store the API key and the number of requests remaining.
+        if (!IsConnected) {
+            // TODO Create a NotConnectedToDatabaseException
+            Console.WriteLine("Not connected to database.");
+            return;
+        }
+
+        // Create a SQL command.
+        SQLiteCommand cmd = Connection.CreateCommand();
+        cmd.CommandText =
+          "CREATE TABLE IF NOT EXISTS ApiTable (" +
+          "API_KEY TEXT, " +
+          "REQUESTS_REMAINING INTEGER, " + 
+          "PRIMARY KEY(API_KEY))";
+
+        // Execute the command
+        cmd.ExecuteNonQuery();
+        Console.WriteLine("API table initialized.");
+    }
+
+    /// <summary>
+    /// Creates a table to store the collection.
+    /// </summary>
+    public void CreateCollection(string collectionName) {
+        // Create a table to store the collection.
+        if (!IsConnected) {
+            // TODO Create a NotConnectedToDatabaseException
+            Console.WriteLine("Not connected to database.");
+            return;
+        }
+        
+        // Create a SQL command.
+        SQLiteCommand cmd = Connection.CreateCommand();
+        cmd.CommandText =
+            $"CREATE TABLE IF NOT EXISTS {collectionName} (" +
+            "PCGS_NUMBER TEXT," +
+            "GRADE TEXT" +
+            "NAME TEXT," +
+            "YEAR INTEGER," +
+            "DENOMINATION TEXT," +
+            "MINT_MARK TEXT," +
+            "PRICE_GUIDE_VALUE REAL," +
+            "COIN_FACTS_LINK TEXT," +
+            "MAJOR_VARIETY TEXT," +
+            "MINOR_VARIETY TEXT," +
+            "DIE_VARIETY TEXT," +
+            "SERIES_NAME TEXT," +
+            "CATEGORY TEXT," +
+            "DESIGNATION TEXT," +
+            "CERT_NUM INTEGER," +
+            "QUANTITY INTEGER," +
+            "NOTES TEXT," +
+            "PRIMARY KEY(PCGS_NUMBER, GRADE))";
+        
+        // Execute the command.
+        cmd.ExecuteNonQuery();
+        Console.WriteLine("Collection table initialized.");
+    }
+
+    /// <summary>
+    /// Inserts a Coin object into the database.
+    /// </summary>
+    public void InsertCoin(Coin coin) {
+        Console.WriteLine("Inserting coin...");
+        // Use our existing connection to insert a coin to the database.
+        if (!IsConnected) {
+            // TODO Create a NotConnectedToDatabaseException
+            Console.WriteLine("Not connected to database.");
+            return;
+        }
+        
+        // Create a SQL command.
+        SQLiteCommand cmd = Connection.CreateCommand();
+        cmd.CommandText =
+            "INSERT INTO CollectionTable (PCGS_NUMBER, GRADE, YEAR," +
+            "DENOMINATION, MINT_MARK, PRICE_GUIDE_VALUE, COIN_FACTS_LINK," +
+            "MAJOR_VARIETY, MINOR_VARIETY, DIE_VARIETY, SERIES_NAME, CATEGORY, DESIGNATION," +
+            "CERT_NUM, QUANTITY, NOTES) " +
+            $"VALUES ('{coin.PCGSNo}', '{coin.Grade}', {coin.Year}, '{coin.Denomination}', '{coin.MintMark}', {coin.PriceGuideValue}," +
+            $"'{coin.CoinFactsLink}', '{coin.MajorVariety}', '{coin.MinorVariety}', '{coin.DieVariety}', '{coin.SeriesName}', " +
+            $"'{coin.Category}', '{coin.Designation}', {coin.CertificateNumber}, {coin.Quantity}, @Notes)";
+        cmd.Parameters.AddWithValue("@Notes", coin.Notes);
+        
+        // Execute the command.
+        cmd.ExecuteNonQuery();
+        Console.WriteLine("Coin inserted.");
+    }
+
+    /// <summary>
+    /// Creates a Coin object and saves it to the database.
+    /// </summary>
+    /// <param name="pcgsNumber">The PCGS number of the coin.</param>
+    /// <param name="grade">The grade of the coin.</param>
+    /// <param name="quantity">The quantity of the coin.</param>
+    /// <returns>The error type returned by the API.</returns>
+    public async Task<PcgsClient.ErrorType> CreateCoin(int pcgsNumber, string grade, int quantity) {
+        Console.WriteLine("Creating coin...");
+        // Create a coin by calling the API, then insert it into the database.
+        // First, check if the coin already exists - if it does, just update the quantity by adding the amount entered.
+        var coin = GetCoin(pcgsNumber, grade);
+        if (coin is not null) {
+            coin.Quantity += quantity;
+            SaveCoin("CollectionTable", coin);
+            return PcgsClient.ErrorType.None;
+        }
+        
+        // Otherwise, build a new coin with the API and insert it.
+        var apiResult = await _pcgsClient.GetCoinFactsByGrade(pcgsNumber, grade);
+        if (apiResult.Item1 == PcgsClient.ErrorType.None) {
+            var newCoin = apiResult.Item2;
+            newCoin.Quantity = quantity;
+            InsertCoin(newCoin);
+            Collection.Add(newCoin);
+            return PcgsClient.ErrorType.None;
+        }
+        
+        Console.WriteLine("Error getting coin from API - {0}", apiResult.Item1);
+        return apiResult.Item1;
+    }
+    
+    /// <summary>
+    /// Gets a coin from the database.
+    /// </summary>
+    /// <param name="pcgsNumber">The PCGS number of the coin.</param>
+    /// <param name="grade">The grade of the coin.</param>
+    /// <returns>The coin if it exists, null otherwise.</returns>
+    public Coin? GetCoin(int pcgsNumber, string grade) {
+        Console.WriteLine($"Getting coin {pcgsNumber}, {grade}...");
+        int gradeInt = GetGradeFromString(grade);
+        
+        // Check the collection to see if the coin exists.
+        // We can't make a more efficient algorithm since there's not really an ordering to the collection.
+        foreach (var coin in Collection) {
+            if (coin.PCGSNo == pcgsNumber.ToString() && coin.Grade.Contains(gradeInt.ToString())) {  // This has the possibility of a false positive for single digit grades.
+                if (gradeInt < 10)
+                    if (char.IsDigit(coin.Grade[3])) continue;  // TODO For right now, we're going to assume that the first 2 characters are ciruclation strings, and the next 2 are grade numbers.
+                Console.WriteLine("Found coin.");
+                return coin;
+            }
+        }
+        
+        Console.WriteLine("Couldn't find coin.");
+        return null;
+    }
+
+    /// <summary>
+    /// Used to get all Coin objects within the database.
+    /// </summary>
+    /// <param name="collectionName">The name of the collection table.</param>
+    public void GetCollection(string collectionName) {
+        Console.WriteLine("Getting collection...");
+        SQLiteCommand cmd = Connection.CreateCommand();
+        cmd.CommandText = $"SELECT * FROM {collectionName}";
+        
+        using (var reader = cmd.ExecuteReader()) {
+            while (reader.Read()) {
+                // Create coin from reader then add to list.
+                Collection.Add(CoinFromReader(reader));
+            }
+        }
+    }
+
+    /// <summary>
+    /// Creates a CSV formatted string from a collection.
+    /// </summary>
+    /// <param name="collectionName">The name of the collection table.</param>
+    /// <returns>A CSV formatted string.</returns>
+    public String CollectionToCSV(string collectionName) {
+        var cmd = Connection.CreateCommand();
+        cmd.CommandText = $"SELECT * FROM {collectionName}";
+
+        var headersCommand = Connection.CreateCommand();
+        headersCommand.CommandText = $"PRAGMA table_info({collectionName})";
+        
+        var resultString = "";
+        var numHeaders = 0;
+        
+        // Get the headers.
+        using (var reader = headersCommand.ExecuteReader()) {
+            while (reader.Read()) {
+                resultString += reader.GetString(1) + ",";
+                numHeaders++;
+            }
+        }
+
+        resultString += "\n";
+
+        // Is there a more efficient way of doing this? This is running at O(n^2) time.
+        using (var reader = cmd.ExecuteReader()) {
+            while (reader.Read()) {
+                // Read information from the reader, then add to CSV string.
+                for (int i = 0; i < numHeaders; i++) {
+                    // Get the type of each column.
+                    var type = reader.GetFieldType(i);
+                    Console.WriteLine("Type: " + type);
+                    if (type == typeof(Int64)) {
+                        resultString += reader.GetInt32(i) + ",";
+                    }
+                    else if (type == typeof(Double)) {
+                        resultString += reader.GetDouble(i) + ",";
+                    }
+                    else if (type == typeof(String)) {
+                        resultString += reader.GetString(i) + ",";
+                    }
+                    else {
+                        resultString += "NULL" + ",";
+                    }
+                }
+                resultString += "\n";
+            }
+        }
+
+        return resultString;
+    }
+
+    /// <summary>
+    /// Saves a Coin object to the database.
+    /// </summary>
+    /// <param name="collectionName">The name of the collection table.</param>
+    /// <param name="coin">The coin to save.</param>
+    public void SaveCoin(string collectionName, Coin coin) {
+        // Get and replace the coin from the database.
+        Console.WriteLine("Saving coin...");
+        SQLiteCommand cmd = Connection.CreateCommand();
+        cmd.CommandText = $"UPDATE {collectionName} " +
+                          $"SET YEAR = {coin.Year}, " +
+                          $"DENOMINATION = \'{coin.Denomination}\', " +
+                          $"MINT_MARK = \'{coin.MintMark}\', " +
+                          $"PRICE_GUIDE_VALUE = \'{coin.PriceGuideValue}\', " +
+                          $"COIN_FACTS_LINK = \'{coin.CoinFactsLink}\', " +
+                          $"MAJOR_VARIETY = \'{coin.MajorVariety}\', " +
+                          $"MINOR_VARIETY = \'{coin.MinorVariety}\', " +
+                          $"DIE_VARIETY = \'{coin.DieVariety}\', " +
+                          $"SERIES_NAME = \'{coin.SeriesName}\', " +
+                          $"CATEGORY = \'{coin.Category}\', " +
+                          $"DESIGNATION = \'{coin.Designation}\', " +
+                          $"CERT_NUM = \'{coin.CertificateNumber}\', " +
+                          $"QUANTITY = {coin.Quantity}, " +
+                          $"NOTES = @Notes " + 
+                          $"WHERE PCGS_NUMBER = {coin.PCGSNo} AND GRADE = \'{coin.Grade}\'";
+        cmd.Parameters.AddWithValue("@Notes", coin.Notes);
+        Console.WriteLine(cmd.CommandText);
+        // Execute the command.
+        cmd.ExecuteNonQuery();
+    }
+
+    /// <summary>
+    /// Synchronizes the database with the current contents of the specified collection.
+    /// </summary>
+    /// <param name="collectionName">The name of the collection table.</param>
+    public void UpdateCollection(string collectionName) {
+        // Update the database with the contents of the collection.
+        // TODO This is a very inefficient way of doing this. I should be able to do this in one command.
+        foreach (var coin in Collection) {
+            SaveCoin(collectionName, coin);  // CAREFUL! This will not create a coin if it doesn't currently exist.
+        }
+    }
+    
+    /// <summary>
+    /// Creates a Coin from the information in a reader specifically from this database.
+    /// </summary>
+    /// <param name="reader">The reader to get the information from.</param>
+    private Coin CoinFromReader(SQLiteDataReader reader) {
+        // Create a coin while filtering out any possible null values - they throw exceptions.
+        Coin coin = new Coin();
+        if (!reader.IsDBNull(0)) coin.PCGSNo = reader.GetString(0);
+        if (!reader.IsDBNull(1)) coin.Grade = reader.GetString(1);
+        if (!reader.IsDBNull(2)) coin.Year = reader.GetInt32(2);
+        if (!reader.IsDBNull(3)) coin.Denomination = reader.GetString(3);
+        if (!reader.IsDBNull(4)) coin.MintMark = reader.GetString(4);
+        if (!reader.IsDBNull(5)) coin.PriceGuideValue = reader.GetDouble(5);
+        if (!reader.IsDBNull(6)) coin.CoinFactsLink = reader.GetString(6);
+        if (!reader.IsDBNull(7)) coin.MajorVariety = reader.GetString(7);
+        if (!reader.IsDBNull(8)) coin.MinorVariety = reader.GetString(8);
+        if (!reader.IsDBNull(9)) coin.DieVariety = reader.GetString(9);
+        if (!reader.IsDBNull(10)) coin.SeriesName = reader.GetString(10);
+        if (!reader.IsDBNull(11)) coin.Category = reader.GetString(11);
+        if (!reader.IsDBNull(12)) coin.Designation = reader.GetString(12);
+        if (!reader.IsDBNull(13)) coin.CertificateNumber = reader.GetInt32(13);
+        if (!reader.IsDBNull(14)) coin.Quantity = reader.GetInt32(14);
+        if (!reader.IsDBNull(15)) coin.Notes = reader.GetString(15);
+        coin.TotalPrice = coin.Quantity * coin.PriceGuideValue;
+        return coin;
+    }
+    
+    /// <summary>
+    /// Deletes a Coin object from the database.
+    /// </summary>
+    /// <param name="delCoin">The coin to delete.</param>
+    public void DeleteCoin(Coin delCoin) {
+        SQLiteCommand cmd = Connection.CreateCommand();
+        cmd.CommandText = "DELETE FROM CollectionTable WHERE PCGS_NUMBER = @PcgsNumber AND GRADE = @Grade";
+        cmd.Parameters.AddWithValue("@PcgsNumber", delCoin.PCGSNo);
+        cmd.Parameters.AddWithValue("@Grade", delCoin.Grade);
+        
+        cmd.ExecuteNonQuery();
+    }
+    
+    /// <summary>
+    /// Gets the grade from a string returned from the main window.
+    /// These are always in a format similar to "MS-65", so we can just get the last two characters.
+    /// </summary>
+    /// <param name="grade">The grade string.</param>
+    private int GetGradeFromString(string grade) {
+        var actualGrade = int.Parse(grade.Substring(grade.Length - 2));
+        Console.WriteLine($"Grade is {actualGrade}");
+        return actualGrade;
+    }
+}
+
+public class NotConnectedToDatabaseException : Exception {
+    public NotConnectedToDatabaseException() : base("Not connected to database.") { }
+}

PcgsInvUi/Services/Database.cs

@@ -1,6 +0,0 @@
-namespace PcgsInvUi.Services;
-
-public class Database
-{
-    // TODO Create a database using SQLite.
-}

PcgsInvUi/Services/PcgsClient.cs

@@ -2,50 +2,128 @@
 using System.Net.Http;
 using System.Net.Http.Headers;
 using System.Threading.Tasks;
-using Newtonsoft.Json;
 using PcgsInvUi.Models;
+using System.Text.Json;
+using ReactiveUI;
 
 namespace PcgsInvUi.Services;
 
-public class PcgsClient
+public class PcgsClient : ReactiveObject {
-{
+    public enum ErrorType {
+        None,
+        NoCoinFound,
+        InvalidRequestFormat,
+        ApiKeyInvalid
+    }
+    
+    public int NumApiRequests {
+        get => _numApiRequests;
+        set => this.RaiseAndSetIfChanged(ref _numApiRequests, value);
+    }
+    
     private string _apiUri = "https://api.pcgs.com/publicapi";
     private readonly string _apiKey;
+    private int _numApiRequests;
 
-    public PcgsClient(string apiKey)
+    /// <summary>
-    {
+    /// Creates a new instance of the PcgsClient class.
+    /// Although this is a constructor, it's meant to be called only from the CreateClient method.
+    /// </summary>
+    private PcgsClient(string apiKey) {
         _apiKey = apiKey;
     }
+    
+    /// <summary>
+    /// Creates a new instance of the PcgsClient class.
+    /// </summary>
+    /// <param name="apiKey">The api key to use for requests.</param>
+    /// <returns>A new instance of the PcgsClient class, or null if the key is invalid.</returns>
+    public static async Task<PcgsClient?> CreateClient(string apiKey) {
+        // Check if the api key is valid.
+        var testClient = new PcgsClient(apiKey);
+        var validCreds = await testClient.VerifyCredentials();
+        if (!validCreds) return null;
+        return testClient;
+    }
+
+    /// <summary>
+    /// Sends a request to the API to verify the credentials.
+    /// </summary>
+    /// <returns>A boolean indicating whether or not the credentials are valid.</returns>
+    public async Task<bool> VerifyCredentials() {
+        // Create a way to check if the api key given is valid
+        // I think the best way to do this is to make a request to the api and see if it returns the expected response.
+        var result = await this.GetCoinFactsByGrade(1, "AG-03");  // This is a known invalid coin id - this is because the api is very fast with invalid requests.
+        if (result.Item1 == ErrorType.ApiKeyInvalid) return false;
+        return true;
+    }
+
+    /// <summary>
+    /// Gets the coin information for a given PCGS number and grade.
+    /// </summary>
+    /// <param name="pcgsNumber">The PCGS number of the coin.</param>
+    /// <param name="grade">The grade of the coin.</param>
+    /// <param name="plusGrade">Whether or not the coin is a plus grade.</param>
+    /// <returns>A tuple containing the error type and the coin information.</returns>
+    public async Task<(ErrorType, Coin?)> GetCoinFactsByGrade(int pcgsNumber, string grade, bool plusGrade = false) {
+        using (HttpClient client = new HttpClient()) {
+            var gradeParam = GetGradeFromString(grade);
 
-    public async Task<Coin> GetCoinFactsByGrade(int pcgsNumber, int grade, bool plusGrade)
-    {
-        Coin newCoin = null;
-        using (HttpClient client = new HttpClient())
-        {
             string requestUri =
-                $"{_apiUri}/coindetail/GetCoinFactsByGrade/?PCGSNo={pcgsNumber}&GradeNo={grade}&PlusGrade={plusGrade}";
+                $"{_apiUri}/coindetail/GetCoinFactsByGrade/?PCGSNo={pcgsNumber}&GradeNo={gradeParam}&PlusGrade={plusGrade}";
             client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("bearer", _apiKey);
+            Console.WriteLine($"Sending request to {requestUri}");
             HttpResponseMessage response = await client.GetAsync(requestUri);
+            Console.WriteLine("Got response.");
 
-            if (response.IsSuccessStatusCode)
+            if (response.IsSuccessStatusCode) {
-            {
+                // Check response for errors.
                 string jsonResponse = await response.Content.ReadAsStringAsync();
-                newCoin = ParseJsonResponse(jsonResponse);
+                var parsedResponse = ParseJsonResponse(jsonResponse);
-            }
+                return parsedResponse;
-            else
-            {
-                Console.WriteLine($"Error: {response.StatusCode} - {response.ReasonPhrase}");
             }
         }
-
-        return newCoin;
-    }
         
-    // TODO Will eventually create the other methods that are included in the Public API.
+        return (ErrorType.ApiKeyInvalid, null);
-
-    private Coin ParseJsonResponse(string json)
-    {
-        Coin newCoin = JsonConvert.DeserializeObject<Coin>(json);
-        return newCoin;
     }
-}
+
+    /// <summary>
+    /// Utility function to parse the grade number from the grade string passed from the front end.
+    /// </summary>
+    /// <param name="grade">The grade string.</param>
+    /// <returns>The grade number.</returns>
+    private int GetGradeFromString(string grade) {
+        var actualGrade = int.Parse(grade.Substring(grade.Length - 2));  // Throws an exception if the grade doesn't exist.
+        Console.WriteLine($"Grade is {actualGrade}");
+        return actualGrade;
+    }
+
+    /// <summary>
+    /// Parses the json response from the api.
+    /// </summary>
+    /// <param name="json">The json response.</param>
+    /// <returns>A tuple containing an error type and the coin information.</returns>
+    private (ErrorType, Coin?) ParseJsonResponse(string json) {
+        Console.WriteLine(json);
+        // Check for errors in the response
+        if (json.Contains("\"ServerMessage\":\"No data found\"")) return (ErrorType.NoCoinFound, null);
+        if (json.Contains("\"IsValidRequest\":false")) return (ErrorType.InvalidRequestFormat, null);
+
+        var newCoin = JsonSerializer.Deserialize<Coin>(json);
+        return (ErrorType.None, newCoin);
+    }
+}
+
+// Exception for invalid request format
+class InvalidRequestFormatException : Exception {
+    public InvalidRequestFormatException() { }
+    public InvalidRequestFormatException(string message) : base(message) { }
+    public InvalidRequestFormatException(string message, Exception inner) : base(message, inner) { }
+}
+
+// Exception for no coin found
+class CoinNotFoundException : Exception {
+    public CoinNotFoundException() { }
+    public CoinNotFoundException(string message) : base(message) { }
+    public CoinNotFoundException(string message, Exception inner) : base(message, inner) { }
+}

PcgsInvUi/ViewLocator.cs

@@ -5,23 +5,19 @@ using PcgsInvUi.ViewModels;
 
 namespace PcgsInvUi;
 
-public class ViewLocator : IDataTemplate
+public class ViewLocator : IDataTemplate {
-{
+    public Control Build(object data) {
-    public Control Build(object data)
-    {
         var name = data.GetType().FullName!.Replace("ViewModel", "View");
         var type = Type.GetType(name);
 
-        if (type != null)
+        if (type != null) {
-        {
             return (Control)Activator.CreateInstance(type)!;
         }
-        
+
         return new TextBlock { Text = "Not Found: " + name };
     }
 
-    public bool Match(object data)
+    public bool Match(object data) {
-    {
         return data is ViewModelBase;
     }
 }

PcgsInvUi/ViewModels/ApiKeyViewModel.cs

@@ -0,0 +1,30 @@
+using ReactiveUI;
+using System.Reactive;
+
+namespace PcgsInvUi.ViewModels;
+
+public class ApiKeyViewModel : ViewModelBase {
+    public string ApiKeyInput {
+        get => _apiKeyInput;
+        set => this.RaiseAndSetIfChanged(ref _apiKeyInput, value);
+    }
+    private string _apiKeyInput = "";
+
+    public bool OkEnabled {
+        get => _okEnabled;
+        set => this.RaiseAndSetIfChanged(ref _okEnabled, value);
+    }
+    private bool _okEnabled;
+
+    public ReactiveCommand<Unit, string> OkCommand { get; }
+
+    public ApiKeyViewModel() {
+        var okEnabled = this.WhenAnyValue(
+            x => x.ApiKeyInput,
+            x => !string.IsNullOrWhiteSpace(x));
+
+
+        // Get the API key from the user.
+        OkCommand = ReactiveCommand.Create(() => ApiKeyInput, okEnabled);
+    }
+}

PcgsInvUi/ViewModels/CoinListViewModel.cs

@@ -5,19 +5,18 @@ using ReactiveUI;
 
 namespace PcgsInvUi.ViewModels;
 
-public class CoinListViewModel : ViewModelBase
+public class CoinListViewModel : ViewModelBase {
-{
     public ObservableCollection<Coin> CoinCollection { get; set; }
     private float _totalValue;
-    public float TotalValue
+
-    {
+    public float TotalValue {
         get => _totalValue;
         set => this.RaiseAndSetIfChanged(ref _totalValue, value);
     }
+
     public Coin? SelectedCoin { get; set; }
-    
+
-    public CoinListViewModel(IEnumerable<Coin> items)
+    public CoinListViewModel(IEnumerable<Coin> items) {
-    {
         CoinCollection = new ObservableCollection<Coin>(items);
         TotalValue = 0;
     }

PcgsInvUi/ViewModels/DeleteWindowViewModel.cs

@@ -0,0 +1,14 @@
+using System.Reactive;
+using ReactiveUI;
+
+namespace PcgsInvUi.ViewModels;
+
+public class DeleteWindowViewModel : ViewModelBase {
+    public ReactiveCommand<Unit, object> OkCommand { get; }
+    public ReactiveCommand<Unit, object> CancelCommand { get; }
+
+    public DeleteWindowViewModel() {
+        OkCommand = ReactiveCommand.Create(() => (object)true);
+        CancelCommand = ReactiveCommand.Create(() => (object)false);
+    }
+}

PcgsInvUi/ViewModels/EditViewModel.cs

@@ -1,30 +1,27 @@
-using System;
+using System.Reactive;
-using System.Reactive;
 using PcgsInvUi.Models;
 using ReactiveUI;
 
 namespace PcgsInvUi.ViewModels;
 
-public class EditViewModel : ViewModelBase
+public class EditViewModel : ViewModelBase {
-{
     public Coin CurrentCoin { get; set; }
-    
+
     public ReactiveCommand<Unit, Unit> OkCommand { get; }
 
-    public EditViewModel(Coin coin)
+    public EditViewModel(Coin coin) {
-    {
         CurrentCoin = coin;
 
         var okEnabled = this.WhenAnyValue(
-            x => x.CurrentCoin.PcgsNumber,
+            x => x.CurrentCoin.PCGSNo,
             x => x.CurrentCoin.Grade,
             x => x.CurrentCoin.Quantity,
-            (id, grade, quantity) => (id != 0) &&
+            (id, grade, quantity) => !string.IsNullOrWhiteSpace(id) &&
                                      !string.IsNullOrWhiteSpace(grade) &&
                                      (quantity != 0)
         );
-        
+
         // Setup OkCommand - all Coin-related properties must be non-whitespace.
         OkCommand = ReactiveCommand.Create(() => { });
     }
-}
+}

PcgsInvUi/ViewModels/ErrorWindowViewModel.cs

@@ -0,0 +1,23 @@
+using System.Reactive;
+using ReactiveUI;
+
+namespace PcgsInvUi.ViewModels; 
+
+public class ErrorWindowViewModel : ViewModelBase {
+
+    public string DisplayedMessage {
+        get => _message;
+        set => this.RaiseAndSetIfChanged(ref _message, value);
+    }
+    private string _message;
+
+    public ReactiveCommand<Unit, object> CloseCommand { get; }
+    
+    public ErrorWindowViewModel(string message)
+    {
+        _message = message;
+
+        CloseCommand = ReactiveCommand.Create(() => (object)false);
+    }
+
+}

PcgsInvUi/ViewModels/FindWindowViewModel.cs

@@ -0,0 +1,8 @@
+using System.Reactive;
+using ReactiveUI;
+
+namespace PcgsInvUi.ViewModels;
+
+public class FindWindowViewModel : ViewModelBase {
+    public ReactiveCommand<Unit, object> OkCommand { get; } = ReactiveCommand.Create(() => (object)1);
+}

PcgsInvUi/ViewModels/MainWindowViewModel.cs

@@ -1,66 +1,141 @@
 using System;
+using System.Collections.ObjectModel;
+using System.IO;
+using System.Linq;
+using System.Reactive;
 using System.Reactive.Linq;
 using PcgsInvUi.Models;
 using PcgsInvUi.Services;
 using ReactiveUI;
+using System.Threading.Tasks;
 
 namespace PcgsInvUi.ViewModels;
 
-public class MainWindowViewModel : ViewModelBase
+public class MainWindowViewModel : ViewModelBase {
-{
+    public ViewModelBase SidebarContent {
-    public CoinListViewModel List { get; }
-    private ViewModelBase _mainContent;
-    private ViewModelBase _sideContent;
-    
-    public MainWindowViewModel(CoinCollection coins)
-    {
-        List = new CoinListViewModel(coins.GetItems());
-        MainContent = List;
-    }
-    
-    public ViewModelBase MainContent
-    {
-        get => _mainContent;
-        private set => this.RaiseAndSetIfChanged(ref _mainContent, value);
-    }
-
-    public ViewModelBase SidebarContent
-    {
         get => _sideContent;
         private set => this.RaiseAndSetIfChanged(ref _sideContent, value);
     }
+    public ObservableCollection<Coin> DisplayedList { get; set; }
+    public CoinDatabase ConnectedCoinDatabase { get; set; }
+    public Coin? SelectedCoin {
+        get => _selectedCoin;
+        set => this.RaiseAndSetIfChanged(ref _selectedCoin, value);
+    }
+    public double TotalValue {
+        get => _totalValue;
+        set => this.RaiseAndSetIfChanged(ref _totalValue, value);
+    }
 
-    public void AddItem()
+    public ReactiveCommand<Unit, Unit> DeleteCommand { get; }
-    {
+    public Interaction<DeleteWindowViewModel, Boolean> ShowDeleteWindow { get; }
+    public ReactiveCommand<Unit, Unit> ExportCommand { get; }
+    public Interaction<Unit, Uri> ShowExportWindow { get; }
+    public Interaction<ErrorWindowViewModel, bool> ShowErrorWindow { get; }
+
+    private ViewModelBase _sideContent;
+    private Coin? _selectedCoin;
+    private double _totalValue;
+
+    public MainWindowViewModel(CoinDatabase coins) {
+        ConnectedCoinDatabase = coins;
+        var keyFound = Task.Run(() => coins.TryInitApiClient()).Result;
+        Console.WriteLine("Function completed.");
         var newViewModel = new NewViewModel();
+        var apiKeyViewModel = new ApiKeyViewModel();
+        // DisplayedList = CoinCollection = new ObservableCollection<Coin>(coins.GetItems());
+        DisplayedList = ConnectedCoinDatabase.Collection;
+        TotalValue = DisplayedList.Sum(x => x.TotalPrice);
 
-        Observable.Merge(
+        // Setup interaction to show ApiKeyWindow
-                newViewModel.OkCommand,
+        apiKeyViewModel.OkCommand.Subscribe(async apiKey => {
-                newViewModel.CancelCommand.Select(_ => (Coin?)null))
+            if (await ConnectedCoinDatabase.TryInitApiClient(apiKey))
-            .Take(1)
+                SidebarContent = newViewModel;  // Must assign this to the observable property rather than private variable.
-            .Subscribe(model =>
+            });
-            {
-                if (model != null)
-                    List.CoinCollection.Add(model);
 
-                MainContent = List;
+        // Check if API key must be entered.
+        if (!keyFound) {
+            Console.WriteLine("API key must be entered by user.");
+            // Show the API key input view.
+            _sideContent = apiKeyViewModel;
+        } else _sideContent = newViewModel;
+        
+        // Set up the ability to show the error window.
+        ShowErrorWindow = new Interaction<ErrorWindowViewModel, bool>();
+        
+        // Set up the ability to open the delete window.
+        ShowDeleteWindow = new Interaction<DeleteWindowViewModel, bool>();
+        var deleteEnabled = this.WhenAnyValue(x => x.SelectedCoin)
+            .Select(x => x != null);
+        DeleteCommand = ReactiveCommand.CreateFromTask(async () => {
+            var deleteViewModel = new DeleteWindowViewModel();
+            var result = await ShowDeleteWindow.Handle(deleteViewModel);
+            if (result && SelectedCoin is not null) {
+                ConnectedCoinDatabase.DeleteCoin(SelectedCoin);
+                ConnectedCoinDatabase.Collection.Remove(SelectedCoin);
+            }
+        }, deleteEnabled);
+
+        ShowExportWindow = new Interaction<Unit, Uri>();
+        ExportCommand = ReactiveCommand.CreateFromTask(async () => {
+            try {
+                var filePath = await ShowExportWindow.Handle(Unit.Default);
+                var stream = File.Open(filePath.AbsolutePath, FileMode.OpenOrCreate);
+                var writer = new StreamWriter(stream);
+                await writer.WriteAsync(ConnectedCoinDatabase.CollectionToCSV("CollectionTable"));
+                await writer.FlushAsync();
+            }
+            catch (IOException e) {
+                // Something is wrong with the file after it's been created.
+                Console.WriteLine(e.Message);
+                await ShowErrorWindow.Handle(new ErrorWindowViewModel(e.Message));
+            } catch (Exception e) {
+                Console.WriteLine(e.Message);
+                await ShowErrorWindow.Handle(new ErrorWindowViewModel(e.Message));
+            }
+        });
+        
+        // Subscribe to SidebarContent.OkCommand, which is an IObservable<(int, string, int)>
+        // This is the same as the above, but with a different syntax.
+        newViewModel.OkCommand
+            .Subscribe(async requestStructure => {
+                var result = await ConnectedCoinDatabase.CreateCoin(requestStructure.Item1, requestStructure.Item2,
+                    requestStructure.Item3);
+                
+                switch (result) {
+                    case PcgsClient.ErrorType.ApiKeyInvalid:
+                        Console.WriteLine("API key is invalid - showing window.");
+                        await ShowErrorWindow.Handle(new ErrorWindowViewModel("API key is invalid - authorization failed."));
+                        break;
+                    case PcgsClient.ErrorType.InvalidRequestFormat:
+                        Console.WriteLine("Request format is invalid - showing window.");
+                        await ShowErrorWindow.Handle(new ErrorWindowViewModel("Request format is invalid."));
+                        break;
+                    case PcgsClient.ErrorType.NoCoinFound:
+                        Console.WriteLine("No coin was found with the given parameters.");
+                        await ShowErrorWindow.Handle(new ErrorWindowViewModel("No coin was found with the given parameters."));
+                        break;
+                }
+                
+                // Clear the text boxes.
+                newViewModel.ClearText();
             });
         
-        MainContent = newViewModel;
+        // Update TotalValue anytime a coin's quantity changes.
+        // Possible null reference is currently ignored - SelectedCoin will never be null.
+        this.WhenAnyValue(x => x.SelectedCoin.TotalPrice)
+            .Subscribe(_ => TotalValue = ConnectedCoinDatabase.Collection.Sum(x => x.TotalPrice));
+
+        // Update TotalValue anytime a coin is added or removed.
+        ConnectedCoinDatabase.Collection.CollectionChanged += (sender, args) => {
+            TotalValue = ConnectedCoinDatabase.Collection.Sum(x => x.TotalPrice);
+        };
     }
 
-    public void EditItem()
+    // Create destructor to save the database when the application exits.
-    {
+    // This is necessary because the database is initialized in this class.
-        var editViewModel = new EditViewModel(List.SelectedCoin);
+    ~MainWindowViewModel() {
-    }
+        Console.WriteLine("Running MainWindowViewModel destructor.");
-
+        ConnectedCoinDatabase.UpdateCollection("CollectionTable");
-    public void DeleteItem()
-    {
-        
-    }
-
-    public void FindItem()
-    {
-        
     }
 }

PcgsInvUi/ViewModels/NewViewModel.cs

@@ -1,36 +1,32 @@
-using System;
+using System.Reactive;
-using System.Reactive;
 using System.Collections.Generic;
-using PcgsInvUi.Models;
 using ReactiveUI;
 
 namespace PcgsInvUi.ViewModels;
 
-public class NewViewModel : ViewModelBase
+public class NewViewModel : ViewModelBase {
-{
+    private string _pcgsNumber = "";
-    private string _pcgsNumber;
+    private string _grade = "";
-    private string _grade;
+    private string _quantity = "";
-    private string _quantity;
+
-    
+    public string PcgsNumber {
-    public string PcgsNumber
-    {
         get => _pcgsNumber;
         set => this.RaiseAndSetIfChanged(ref _pcgsNumber, value);
     }
-    public string Grade
+
-    {
+    public string Grade {
         get => _grade;
         set => this.RaiseAndSetIfChanged(ref _grade, value);
     }
-    public string Quantity
+
-    {
+    public string Quantity {
         get => _quantity;
         set => this.RaiseAndSetIfChanged(ref _quantity, value);
     }
+
     public List<string> GradesList { get; }
 
-    public NewViewModel()
+    public NewViewModel() {
-    {
         var okEnabled = this.WhenAnyValue(
             x => x.PcgsNumber,
             x => x.Grade,
@@ -39,19 +35,17 @@ public class NewViewModel : ViewModelBase
                                      !string.IsNullOrWhiteSpace(grade) &&
                                      !string.IsNullOrWhiteSpace(quantity));
 
-        // This will eventually send our request to the public API, then construct our coin.
         OkCommand = ReactiveCommand.Create(
-            () => new Coin { PcgsNumber = Int32.Parse(PcgsNumber),
+            () => (int.Parse(PcgsNumber), Grade, int.Parse(Quantity)),
-                Grade = Grade,
-                Quantity = Int32.Parse(Quantity) },
             okEnabled);
-        
+
-        CancelCommand = ReactiveCommand.Create(() => { });
+        ClearCommand = ReactiveCommand.Create(() => {
+            ClearText();
+        });
 
         // Initialize grade values for use in the view.
         // This must be typed out manually, as there is no way to get a list of grades from the API.
-        GradesList = new List<string>()
+        GradesList = new List<string> {
-        {
             "P-01",
             "FR-02",
             "AG-03",
@@ -85,7 +79,15 @@ public class NewViewModel : ViewModelBase
         };
     }
 
-    public ReactiveCommand<Unit, Coin> OkCommand { get; }
+    public ReactiveCommand<Unit, (int, string, int)> OkCommand { get; }
-    public ReactiveCommand<Unit, Unit> CancelCommand { get; }
+    public ReactiveCommand<Unit, Unit> ClearCommand { get; }
 
-}
+    /// <summary>
+    /// Clears the text fields.
+    /// </summary>
+    public void ClearText() {
+        PcgsNumber = "";
+        Grade = "";
+        Quantity = "";
+    }
+}

PcgsInvUi/ViewModels/ViewModelBase.cs

@@ -2,6 +2,4 @@
 
 namespace PcgsInvUi.ViewModels;
 
-public class ViewModelBase : ReactiveObject
+public class ViewModelBase : ReactiveObject { }
-{
-}

PcgsInvUi/Views/ApiKeyView.axaml

@@ -0,0 +1,14 @@
+<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:viewModels="clr-namespace:PcgsInvUi.ViewModels"
+        mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
+        x:Class="PcgsInvUi.Views.ApiKeyView" x:DataType="viewModels:ApiKeyViewModel" >
+    <StackPanel>
+        <Label Content="API key was not found or did not authenticate." /> 
+        <Label Content="Please enter your API key below:" />
+        <TextBox Margin="10" Text="{Binding ApiKeyInput}" />
+        <Button HorizontalAlignment="Center" Content="Submit" Command="{Binding OkCommand}" />
+    </StackPanel>
+</UserControl>

PcgsInvUi/Views/ApiKeyView.axaml.cs

@@ -0,0 +1,9 @@
+using Avalonia.Controls;
+
+namespace PcgsInvUi.Views; 
+
+public partial class ApiKeyView : UserControl {
+    public ApiKeyView() {
+        InitializeComponent();
+    }
+}

PcgsInvUi/Views/CoinListView.axaml

@@ -1,73 +0,0 @@
-<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:viewModels="clr-namespace:PcgsInvUi.ViewModels"
-             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
-             x:Class="PcgsInvUi.Views.CoinListView"
-             x:DataType="viewModels:CoinListViewModel">
-    <DockPanel>
-        <DockPanel DockPanel.Dock="Top">
-            <DataGrid x:Name="CollectionView"
-                      HorizontalAlignment="Stretch"
-                      VerticalAlignment="Top"
-                      DockPanel.Dock="Top"
-                      ItemsSource="{Binding CoinCollection}"
-                      SelectedItem="{Binding SelectedCoin, Mode=TwoWay}"
-                      AutoGenerateColumns="False"
-                      CanUserResizeColumns="True" >
-                <DataGrid.Columns>
-                    <DataGridTextColumn Header="Series" Width="*"
-                                        Binding="{Binding Series}"
-                                        IsReadOnly="True"/>
-                    <DataGridTextColumn Header="Year"         
-                                        Binding="{Binding Year}"
-                                        IsReadOnly="True"/>
-                    <DataGridTextColumn Header="Mint" Width="*"
-                                        Binding="{Binding MintMark}"
-                                        IsReadOnly="True"/>
-                    <DataGridTextColumn Header="Denomination" Width="*"
-                                        Binding="{Binding Denomination}"
-                                        IsReadOnly="True"/>
-                    <DataGridTextColumn Header="Variety" Width="*"
-                                        Binding="{Binding MajorVariety}"
-                                        IsReadOnly="True"/>
-                    <DataGridTextColumn Header="Grade" Width="*"
-                                        Binding="{Binding Grade}"
-                                        IsReadOnly="True"/>
-                    <DataGridTextColumn Header="Designation" Width="*"
-                                        Binding="{Binding Designation}"
-                                        IsReadOnly="True"/>
-                    <DataGridTextColumn Header="Est. Price" Width="*"
-                                        Binding="{Binding PriceGuideValue}" 
-                                        IsReadOnly="False"/>
-                    <DataGridTextColumn Header="PCGS #" Width="*"
-                                        Binding="{Binding PcgsNumber}"
-                                        IsReadOnly="True"/>
-                    <DataGridTextColumn Header="Quantity" Width="*"
-                                        Binding="{Binding Quantity}" 
-                                        IsReadOnly="False"/>
-                    <DataGridTextColumn Header="Total Price" Width="*"
-                                        Binding="{Binding TotalPrice}"
-                                        IsReadOnly="True" />
-                </DataGrid.Columns>
-            </DataGrid>
-        </DockPanel>
-        <DockPanel DockPanel.Dock="Bottom">
-            <Grid HorizontalAlignment="Left" VerticalAlignment="Bottom" Margin="5" ColumnDefinitions="Auto, Auto, Auto, Auto" DockPanel.Dock="Left">
-                <Button Grid.Column="0" Margin="5" Width="100" HorizontalContentAlignment="Center" Content="New..."
-                        Command="{Binding $parent[Window].((viewModels:MainWindowViewModel)DataContext).AddItem}"/>
-                <Button Grid.Column="1" Margin="5" Width="100" HorizontalContentAlignment="Center" Content="Edit..." 
-                        Command="{Binding $parent[Window].((viewModels:MainWindowViewModel)DataContext).EditItem}"/>
-                <Button Grid.Column="2" Margin="5" Width="100" HorizontalContentAlignment="Center" Content="Delete"  
-                        Command="{Binding $parent[Window].((viewModels:MainWindowViewModel)DataContext).DeleteItem}"/>
-                <Button Grid.Column="3" Margin="5" Width="100" HorizontalContentAlignment="Center" Content="Find..." 
-                        Command="{Binding $parent[Window].((viewModels:MainWindowViewModel)DataContext).FindItem}"/>
-            </Grid>
-            <Grid HorizontalAlignment="Right" VerticalAlignment="Bottom" Margin="5" ColumnDefinitions="Auto, Auto" DockPanel.Dock="Right">
-                <Label Grid.Column="0" Margin="5" VerticalAlignment="Center" Content="{Binding TotalValue, StringFormat='Total Value: ${0:0.00}'}" />
-                <Button Grid.Column="1" Margin="5" Width="150" HorizontalContentAlignment="Center" Content="Export to CSV..." />
-            </Grid>
-        </DockPanel>
-    </DockPanel>
-</UserControl>

PcgsInvUi/Views/CoinListView.axaml.cs

@@ -1,13 +0,0 @@
-using Avalonia;
-using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
-
-namespace PcgsInvUi.Views;
-
-public partial class CoinListView : UserControl
-{
-    public CoinListView()
-    {
-        InitializeComponent();
-    }
-}

PcgsInvUi/Views/DeleteWindow.axaml

@@ -1,24 +1,24 @@
 <Window 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:viewModels="clr-namespace:PcgsInvUi.ViewModels"
         d:DesignWidth="325" d:DesignHeight="100"
-        x:Class="PcgsInvUi.Views.DeleteWindow"
+        x:Class="PcgsInvUi.Views.DeleteWindow" x:DataType="viewModels:DeleteWindowViewModel"
         Width="325" Height="100" WindowStartupLocation="CenterOwner"
         Title="DeleteWindow">
     <Grid ColumnDefinitions="*, *" RowDefinitions="*, *">
-        <Label Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="2"  Margin="10"
+        <Label Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="2" Margin="10"
                HorizontalAlignment="Center" VerticalAlignment="Center"
-               Content="Are you sure you want to delete this item?"/>
+               Content="Are you sure you want to delete this item?" />
-        <Button Grid.Row="1" Grid.Column="0" Margin="5" 
+        <Button Grid.Row="1" Grid.Column="0" Margin="5"
                 Width="100"
-                HorizontalAlignment="Stretch" VerticalAlignment="Center" 
+                HorizontalAlignment="Stretch" VerticalAlignment="Center"
                 HorizontalContentAlignment="Center"
-                Content="Yes" Click="AcceptClicked"/>
+                Content="Yes" Command="{Binding OkCommand}" />
         <Button Grid.Row="1" Grid.Column="1" Margin="5"
                 Width="100"
-                HorizontalAlignment="Stretch" VerticalAlignment="Center" 
+                HorizontalAlignment="Stretch" VerticalAlignment="Center"
-                HorizontalContentAlignment="Center" 
+                HorizontalContentAlignment="Center" IsEnabled="True"
-                Content="No" Click="CancelClicked"/>
+                Content="No" Command="{Binding CancelCommand}" />
     </Grid>
-</Window>
+</Window>

PcgsInvUi/Views/DeleteWindow.axaml.cs

@@ -1,27 +1,14 @@
-using Avalonia.Controls;
+using PcgsInvUi.ViewModels;
-using Avalonia.Interactivity;
+using Avalonia.ReactiveUI;
+using ReactiveUI;
+using System;
 
 namespace PcgsInvUi.Views;
 
-public partial class DeleteWindow : Window
+public partial class DeleteWindow : ReactiveWindow<DeleteWindowViewModel> {
-{
+    public DeleteWindow() {
-    public bool Accepted { get; set; }
-    
-    public DeleteWindow()
-    {
         InitializeComponent();
-        Accepted = false;
+        this.WhenActivated(d => d(ViewModel!.OkCommand.Subscribe(Close)));
+        this.WhenActivated(d => d(ViewModel!.CancelCommand.Subscribe(Close)));
     }
-    
+}
-    public void AcceptClicked(object source, RoutedEventArgs args)
-    {
-        // TODO Delete the SelectedCoin?
-        Accepted = true;
-        Close();
-    }
-    
-    public void CancelClicked(object source, RoutedEventArgs args)
-    {
-        Close();
-    }
-}

PcgsInvUi/Views/ErrorWindow.axaml

@@ -0,0 +1,18 @@
+<Window 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:viewModels="clr-namespace:PcgsInvUi.ViewModels"
+        mc:Ignorable="d" d:DesignWidth="300" d:DesignHeight="150"
+        x:Class="PcgsInvUi.Views.ErrorWindow" x:DataType="viewModels:ErrorWindowViewModel"
+        Title="Error!" SizeToContent="WidthAndHeight" WindowStartupLocation="CenterOwner" 
+        x:Name="NameErrorWindow" CanResize="False" >
+    <Grid RowDefinitions="*,*">
+        <Label Grid.Row="0" HorizontalAlignment="Center" VerticalAlignment="Stretch"
+               Margin="15"
+               Content="{Binding DisplayedMessage}" />
+        <Button Grid.Row="1" HorizontalAlignment="Center" VerticalAlignment="Bottom"
+                Margin="10" Name="CloseButton" IsEnabled="True"
+                Content="OK" Command="{Binding CloseCommand, Mode=OneWay}" />
+    </Grid>
+</Window>

PcgsInvUi/Views/ErrorWindow.axaml.cs

@@ -0,0 +1,14 @@
+using System;
+using Avalonia.ReactiveUI;
+using PcgsInvUi.ViewModels;
+using ReactiveUI;
+
+namespace PcgsInvUi.Views; 
+
+public partial class ErrorWindow : ReactiveWindow<ErrorWindowViewModel> {
+    public ErrorWindow()
+    {
+        InitializeComponent();
+        this.WhenActivated(d => d(ViewModel!.CloseCommand.Subscribe(Close)));
+    }
+}

PcgsInvUi/Views/FindWindow.axaml

@@ -0,0 +1,14 @@
+<Window 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"
+        mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
+        x:Class="PcgsInvUi.Views.FindWindow"
+        Title="FindWindow">
+    <Grid ColumnDefinitions="Auto, *" RowDefinitions="*, *">
+        <Label Content="PCGS #:" VerticalAlignment="Center" HorizontalAlignment="Right" Margin="5" />
+        <TextBox Grid.Row="0" Grid.Column="1" Margin="5" />
+        <Button Grid.Row="1" Grid.Column="0" Grid.ColumnSpan="2" Content="Find"
+                HorizontalAlignment="Center" Margin="5" Width="75" />
+    </Grid>
+</Window>

PcgsInvUi/Views/FindWindow.axaml.cs

@@ -0,0 +1,13 @@
+using Avalonia.ReactiveUI;
+using PcgsInvUi.ViewModels;
+using ReactiveUI;
+using System;
+
+namespace PcgsInvUi.Views;
+
+public partial class FindWindow : ReactiveWindow<FindWindowViewModel> {
+    public FindWindow() {
+        InitializeComponent();
+        this.WhenActivated(d => d(ViewModel!.OkCommand.Subscribe(Close)));
+    }
+}

PcgsInvUi/Views/MainWindow.axaml

@@ -5,11 +5,76 @@
         xmlns:viewModels="clr-namespace:PcgsInvUi.ViewModels"
         mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
         x:Class="PcgsInvUi.Views.MainWindow" x:DataType="viewModels:MainWindowViewModel"
-        Title="MainWindow">
+        Title="Main Window" WindowStartupLocation="CenterScreen" WindowState="Maximized" >
-    <SplitView Name="Sidebar">
+    <SplitView IsPaneOpen="True"
+               DisplayMode="Inline"
+               PanePlacement="Right">
         <SplitView.Pane>
-            <UserControl Content="{Binding SidebarContent}"/>
+            <Grid RowDefinitions="Auto, *">
+                <UserControl Grid.Row="0" Margin="10, 20, 10, 10" VerticalAlignment="Center"
+                             Content="{Binding SidebarContent}" />
+                <TextBox Grid.Row="1" Margin="5" Watermark="Notes..."
+                         Text="{Binding SelectedCoin.Notes}"
+                         IsReadOnly="False" TextWrapping="Wrap"/>
+            </Grid>
         </SplitView.Pane>
-        <UserControl Content="{Binding MainContent}"/>
+        <Grid RowDefinitions="*, Auto" ShowGridLines="False">
+            <DataGrid Grid.Row="0" HorizontalAlignment="Stretch"
+                      VerticalAlignment="Stretch"
+                      ItemsSource="{Binding DisplayedList}"
+                      SelectedItem="{Binding SelectedCoin, Mode=TwoWay}"
+                      AutoGenerateColumns="False"
+                      CanUserResizeColumns="True">
+                <DataGrid.Columns>
+                    <DataGridTextColumn Header="Series" Width="*"
+                                        Binding="{Binding SeriesName}"
+                                        IsReadOnly="True" />
+                    <DataGridTextColumn Header="Year"
+                                        Binding="{Binding Year}"
+                                        IsReadOnly="True" />
+                    <DataGridTextColumn Header="Mint" Width="*"
+                                        Binding="{Binding MintMark}"
+                                        IsReadOnly="True" />
+                    <DataGridTextColumn Header="Denomination" Width="*"
+                                        Binding="{Binding Denomination}"
+                                        IsReadOnly="True" />
+                    <DataGridTextColumn Header="Variety" Width="*"
+                                        Binding="{Binding MajorVariety}"
+                                        IsReadOnly="True" />
+                    <DataGridTextColumn Header="Grade" Width="*"
+                                        Binding="{Binding Grade}"
+                                        IsReadOnly="True" />
+                    <DataGridTextColumn Header="Designation" Width="*"
+                                        Binding="{Binding Designation}"
+                                        IsReadOnly="True" />
+                    <DataGridTextColumn Header="Est. Price" Width="*"
+                                        Binding="{Binding PriceGuideValue, StringFormat='${0:0.00}'}"
+                                        IsReadOnly="True" />
+                    <DataGridTextColumn Header="PCGS #" Width="*"
+                                        Binding="{Binding PCGSNo}"
+                                        IsReadOnly="True" />
+                    <DataGridTextColumn Header="Quantity" Width="*"
+                                        Binding="{Binding Quantity}"
+                                        IsReadOnly="False" />
+                    <DataGridTextColumn Header="Total Price" Width="*"
+                                        Binding="{Binding TotalPrice, StringFormat='${0:0.00}'}"
+                                        IsReadOnly="True" />
+                </DataGrid.Columns>
+            </DataGrid>
+            <DockPanel Grid.Row="1">
+                <Grid HorizontalAlignment="Left" VerticalAlignment="Bottom" Margin="5" ColumnDefinitions="Auto, Auto"
+                      DockPanel.Dock="Left">
+                    <Button Grid.Column="0" Margin="5" Width="100" HorizontalContentAlignment="Center" Content="Delete"
+                            Command="{Binding DeleteCommand}" />
+                </Grid>
+                <Grid HorizontalAlignment="Right" VerticalAlignment="Bottom" Margin="5" ColumnDefinitions="Auto, Auto"
+                      DockPanel.Dock="Right">
+                    <Label Grid.Column="0" Margin="5" VerticalAlignment="Center"
+                           Content="{Binding TotalValue, StringFormat='Total Value: ${0:0.00}'}" />
+                    <Button Grid.Column="1" Margin="5" Width="150" HorizontalContentAlignment="Center"
+                            Content="Export to CSV..." Command="{Binding ExportCommand}" />
+                </Grid>
+            </DockPanel>
+        </Grid>
     </SplitView>
 </Window>

PcgsInvUi/Views/MainWindow.axaml.cs

@@ -1,28 +1,63 @@
-using Avalonia;
+using System;
-using Avalonia.Controls;
+using System.Reactive;
-using Avalonia.Markup.Xaml;
+using System.Threading.Tasks;
+using Avalonia.Platform.Storage;
+using Avalonia.ReactiveUI;
+using PcgsInvUi.ViewModels;
+using ReactiveUI;
 
 namespace PcgsInvUi.Views;
 
-public partial class MainWindow : Window
+public partial class MainWindow : ReactiveWindow<MainWindowViewModel> {
-{
+    public MainWindow() {
-    // TODO New window.
-    // TODO Edit window.
-    // TODO Delete window.
-    // TODO Find window.
-    // TODO Export window.
-    // TODO Error handling.
-    // TODO Manual handling of API key.
-    // TODO Use CoinFacts link.
-    // TODO Export to CSV.
-    // TODO Take giant sheet of coins to integrate into the application.
-    // TODO Update all coins.
-    // TODO API request tracker (1000 per day)
-    // TODO API update schedules (per month? manual override? needs to store a date of last update in the coin object)
-
-    
-    public MainWindow()
-    {
         InitializeComponent();
+        this.WhenActivated(d => d(ViewModel!.ShowDeleteWindow.RegisterHandler(ShowDeleteWindowAsync)));
+        this.WhenActivated(d => d(ViewModel!.ShowExportWindow.RegisterHandler(ShowFilePickerAsync)));
+        this.WhenActivated(d => d(ViewModel!.ShowErrorWindow.RegisterHandler(ShowErrorWindowAsync)));
+        // this.WhenActivated(d => d(ViewModel!.ShowFindWindow.RegisterHandler(ShowFindWindowAsync)));
     }
-}
+
+    private async Task ShowDeleteWindowAsync(InteractionContext<DeleteWindowViewModel, bool> interaction) {
+        var window = new DeleteWindow();
+        window.DataContext = interaction.Input;
+
+        var result = await window.ShowDialog<bool>(this);
+        interaction.SetOutput(result);
+    }
+
+    private async Task ShowFindWindowAsync(InteractionContext<FindWindowViewModel, int> interaction) {
+        var window = new FindWindow();
+        window.DataContext = interaction.Input;
+
+        var result = await window.ShowDialog<int>(this);
+        interaction.SetOutput(result);
+    }
+
+    private async Task ShowFilePickerAsync(InteractionContext<Unit, Uri> interationContext) {
+        var topLevel = GetTopLevel(this);
+        if (topLevel is null) throw new Exception("Could not find top level of the file path.");
+        var file = await topLevel.StorageProvider.SaveFilePickerAsync(new FilePickerSaveOptions {
+            Title = "Save CSV...",
+            DefaultExtension = ".csv",
+            ShowOverwritePrompt = true,
+            SuggestedFileName = "coins.csv",
+            SuggestedStartLocation = await StorageProvider.TryGetWellKnownFolderAsync(WellKnownFolder.Documents)
+        });
+
+        if (file is not null) {
+            interationContext.SetOutput(file.Path);
+        }
+        else {
+            // TODO Handle user closing the dialog.
+            throw new Exception("User cancelled the file picker.");
+        }
+    }
+    
+    private async Task ShowErrorWindowAsync(InteractionContext<ErrorWindowViewModel, bool> interaction) {
+        var window = new ErrorWindow();
+        window.DataContext = interaction.Input;
+
+        var result = await window.ShowDialog<bool>(this);
+        interaction.SetOutput(result);
+    }
+}

PcgsInvUi/Views/NewView.axaml

@@ -7,19 +7,20 @@
              x:Class="PcgsInvUi.Views.NewView" x:DataType="viewmodels:NewViewModel">
     <DockPanel>
         <Grid DockPanel.Dock="Top" ColumnDefinitions="Auto, *" RowDefinitions="*, *, *">
-            <Label Grid.Column="0" Grid.Row="0" Margin="5, 5, 20, 5" VerticalAlignment="Center" Content="PCGS #:"/>
+            <Label Grid.Column="0" Grid.Row="0" Margin="5, 5, 20, 5" VerticalAlignment="Center" Content="PCGS #:" />
-            <TextBox Grid.Column="1" Grid.Row="0" Margin="5, 5, 10, 5" Text="{Binding PcgsNumber}"/>
+            <TextBox Grid.Column="1" Grid.Row="0" Margin="5, 5, 10, 5" Text="{Binding PcgsNumber}" />
-            <Label Grid.Column="0" Grid.Row="1" Margin="5, 5, 20, 5" VerticalAlignment="Center" Content="Grade:"/>
+            <Label Grid.Column="0" Grid.Row="1" Margin="5, 5, 20, 5" VerticalAlignment="Center" Content="Grade:" />
             <ComboBox Name="GradeChoices" Grid.Column="1" Grid.Row="1" SelectedIndex="0" Margin="5, 5, 10, 5"
-                      ItemsSource="{Binding GradesList}" SelectedItem="{Binding Grade}"/>
+                      Width="150"
-            <Label Grid.Column="0" Grid.Row="2" Margin="5, 5, 20, 5" VerticalAlignment="Center" Content="Quantity:"/>
+                      ItemsSource="{Binding GradesList}" SelectedItem="{Binding Grade}" />
-            <TextBox Grid.Column="1" Grid.Row="2" Margin="5, 5, 10, 5" Text="{Binding Quantity}"/>
+            <Label Grid.Column="0" Grid.Row="2" Margin="5, 5, 20, 5" VerticalAlignment="Center" Content="Quantity:" />
+            <TextBox Grid.Column="1" Grid.Row="2" Margin="5, 5, 10, 5" Text="{Binding Quantity}" />
         </Grid>
         <Grid DockPanel.Dock="Bottom" ColumnDefinitions="*, *">
-            <Button Grid.Column="0" Margin="5" HorizontalAlignment="Center" VerticalAlignment="Center" 
+            <Button Grid.Column="0" Margin="5" HorizontalAlignment="Center" VerticalAlignment="Center"
-                    Width="90" HorizontalContentAlignment="Center" Content="OK" Command="{Binding OkCommand}"/>
+                    Width="90" HorizontalContentAlignment="Center" Content="OK" Command="{Binding OkCommand}" />
-            <Button Grid.Column="1" Margin="5" HorizontalAlignment="Center" VerticalAlignment="Center" 
+            <Button Grid.Column="1" Margin="5" HorizontalAlignment="Center" VerticalAlignment="Center"
-                    Width="90" HorizontalContentAlignment="Center" Content="Cancel" Command="{Binding CancelCommand}" />
+                    Width="90" HorizontalContentAlignment="Center" Content="Clear" Command="{Binding ClearCommand}" />
         </Grid>
     </DockPanel>
-</UserControl>
+</UserControl>

PcgsInvUi/Views/NewView.axaml.cs

@@ -1,13 +1,9 @@
-using Avalonia;
+using Avalonia.Controls;
-using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
 
 namespace PcgsInvUi.Views;
 
-public partial class NewView : UserControl
+public partial class NewView : UserControl {
-{
+    public NewView() {
-    public NewView()
-    {
         InitializeComponent();
     }
-}
+}

PcgsInvUi/app.manifest

@@ -1,18 +1,18 @@
 <?xml version="1.0" encoding="utf-8"?>
 <assembly manifestVersion="1.0" xmlns="urn:schemas-microsoft-com:asm.v1">
-  <!-- This manifest is used on Windows only.
+    <!-- This manifest is used on Windows only.
-       Don't remove it as it might cause problems with window transparency and embeded controls.
+         Don't remove it as it might cause problems with window transparency and embeded controls.
-       For more details visit https://learn.microsoft.com/en-us/windows/win32/sbscs/application-manifests -->
+         For more details visit https://learn.microsoft.com/en-us/windows/win32/sbscs/application-manifests -->
-  <assemblyIdentity version="1.0.0.0" name="PcgsInvUi.Desktop"/>
+    <assemblyIdentity version="1.0.0.0" name="PcgsInvUi.Desktop"/>
 
-  <compatibility xmlns="urn:schemas-microsoft-com:compatibility.v1">
+    <compatibility xmlns="urn:schemas-microsoft-com:compatibility.v1">
-    <application>
+        <application>
-      <!-- A list of the Windows versions that this application has been tested on
+            <!-- A list of the Windows versions that this application has been tested on
-           and is designed to work with. Uncomment the appropriate elements
+                 and is designed to work with. Uncomment the appropriate elements
-           and Windows will automatically select the most compatible environment. -->
+                 and Windows will automatically select the most compatible environment. -->
 
-      <!-- Windows 10 -->
+            <!-- Windows 10 -->
-      <supportedOS Id="{8e0f7a12-bfb3-4fe8-b9a5-48fd50a15a9a}" />
+            <supportedOS Id="{8e0f7a12-bfb3-4fe8-b9a5-48fd50a15a9a}"/>
-    </application>
+        </application>
-  </compatibility>
+    </compatibility>
 </assembly>

PcgsInvUi/bin/Debug/net6.0/PcgsInvUi.runtimeconfig.json

@@ -1,12 +0,0 @@
-{
-  "runtimeOptions": {
-    "tfm": "net6.0",
-    "framework": {
-      "name": "Microsoft.NETCore.App",
-      "version": "6.0.0"
-    },
-    "configProperties": {
-      "System.Runtime.InteropServices.BuiltInComInterop.IsSupported": true
-    }
-  }
-}