Add placeholder blog post to news panel (#187)

* Add placeholder blog post to news

* Fix Codacy issues

* Fix compile warning

UnitystationLauncher/ViewModels/BlogPostViewModel.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Diagnostics;
+using Avalonia;
+using Avalonia.Media.Imaging;
+using Avalonia.Platform;
+
+namespace UnitystationLauncher.ViewModels;
+
+public class BlogPostViewModel : ViewModelBase
+{
+    private string Title { get; }
+    private string PostLink { get; }
+    private Bitmap PostImage { get; }
+    private Bitmap DarkenBg { get; }
+
+    public BlogPostViewModel(string title, string postLink, Bitmap? postImage)
+    {
+        Title = title;
+        PostLink = postLink;
+        IAssetLoader assets = AvaloniaLocator.Current.GetService<IAssetLoader>()
+                              ?? throw new NullReferenceException("No IAssetLoader found, check Autofac configuration.");
+        // Default image in case one is not provided
+        postImage ??= new(assets.Open(new("avares://StationHub/Assets/bgnews.png")));
+        PostImage = postImage;
+        DarkenBg = new(assets.Open(new("avares://StationHub/Assets/transparentdark.png")));
+    }
+
+    private void OpenLink()
+    {
+        if (string.IsNullOrWhiteSpace(PostLink))
+        {
+            return;
+        }
+
+        ProcessStartInfo psi = new()
+        {
+            FileName = PostLink,
+            UseShellExecute = true
+        };
+        Process.Start(psi);
+    }
+}

UnitystationLauncher/ViewModels/NewsPanelViewModel.cs

@@ -1,12 +1,8 @@
-using Avalonia;
-using Avalonia.Platform;
-using ReactiveUI;
-using Avalonia.Media.Imaging;
-using System;
+using ReactiveUI;
+using System.Collections.ObjectModel;
 using System.Reactive;
 using System.Diagnostics;
 using UnitystationLauncher.Constants;
-using UnitystationLauncher.Models.ConfigFile;
 
 namespace UnitystationLauncher.ViewModels
 {
@@ -16,28 +12,31 @@ public class NewsPanelViewModel : PanelBase
 
         public override bool IsEnabled => true;
 
-        ViewModelBase _changelog;
-
-        Bitmap _backGroundImage;
-
-        public ReactiveCommand<Unit, Unit> OpenMainSite { get; }
-        public ReactiveCommand<Unit, Unit> OpenPatreon { get; }
-        public ReactiveCommand<Unit, Unit> OpenGameIssues { get; }
-        public ReactiveCommand<Unit, Unit> OpenLauncherIssues { get; }
-        public ReactiveCommand<Unit, Unit> OpenDiscordInvite { get; }
-
-        public Bitmap BackGroundImage
+        private ViewModelBase? _currentBlogPost;
+        private ViewModelBase CurrentBlogPost
         {
-            get => _backGroundImage;
-            set => this.RaiseAndSetIfChanged(ref _backGroundImage, value);
+            get => _currentBlogPost ?? new BlogPostViewModel("Loading...", string.Empty, null);
+            set => this.RaiseAndSetIfChanged(ref _currentBlogPost, value);
         }
 
+        private ViewModelBase _changelog;
         public ViewModelBase Changelog
         {
             get => _changelog;
             set => this.RaiseAndSetIfChanged(ref _changelog, value);
         }
 
+        public ReactiveCommand<Unit, Unit> OpenMainSite { get; }
+        public ReactiveCommand<Unit, Unit> OpenPatreon { get; }
+        public ReactiveCommand<Unit, Unit> OpenGameIssues { get; }
+        public ReactiveCommand<Unit, Unit> OpenLauncherIssues { get; }
+        public ReactiveCommand<Unit, Unit> OpenDiscordInvite { get; }
+
+        private ObservableCollection<BlogPostViewModel> BlogPosts { get; }
+        public ReactiveCommand<Unit, Unit> NextBlog { get; }
+        public ReactiveCommand<Unit, Unit> PreviousBlog { get; }
+        private int CurrentBlogPostIndex { get; set; }
+
         public NewsPanelViewModel(ChangelogViewModel changelog)
         {
             _changelog = changelog;
@@ -48,8 +47,46 @@ public NewsPanelViewModel(ChangelogViewModel changelog)
             OpenLauncherIssues = ReactiveCommand.Create(() => OpenLink(LinkUrls.LauncherIssuesUrl));
             OpenDiscordInvite = ReactiveCommand.Create(() => OpenLink(LinkUrls.DiscordInviteUrl));
 
-            var assets = AvaloniaLocator.Current.GetService<IAssetLoader>();
-            _backGroundImage = new Bitmap(assets?.Open(new Uri("avares://StationHub/Assets/bgnews.png")));
+            BlogPosts = new();
+            FetchBlogPosts();
+            NextBlog = ReactiveCommand.Create(NextPost);
+            PreviousBlog = ReactiveCommand.Create(PreviousPost);
+            CurrentBlogPostIndex = 0;
+
+            SetCurrentBlogPost();
+        }
+
+        private void FetchBlogPosts()
+        {
+            // TODO, fetch from blog post API, for now we can just hard code one.
+            BlogPosts.Add(new("Coming soon!", "https://www.unitystation.org/blog", null));
+        }
+
+        private void SetCurrentBlogPost()
+        {
+            CurrentBlogPost = BlogPosts[CurrentBlogPostIndex];
+        }
+
+        private void NextPost()
+        {
+            CurrentBlogPostIndex++;
+            if (CurrentBlogPostIndex >= BlogPosts.Count)
+            {
+                CurrentBlogPostIndex = 0;
+            }
+
+            SetCurrentBlogPost();
+        }
+
+        private void PreviousPost()
+        {
+            CurrentBlogPostIndex--;
+            if (CurrentBlogPostIndex <= 0)
+            {
+                CurrentBlogPostIndex = BlogPosts.Count - 1;
+            }
+
+            SetCurrentBlogPost();
         }
 
         private static void OpenLink(string url)

UnitystationLauncher/Views/BlogPostView.axaml

@@ -0,0 +1,18 @@
+<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"
+             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
+             x:Class="UnitystationLauncher.Views.BlogPostView">
+    <Button Margin="0 0.6 0 0" Command="{Binding OpenLink}">
+        <Panel>
+            <Image Margin="0.5" Source="{Binding PostImage}" Stretch="UniformToFill" Opacity="0.459" />
+
+            <Panel VerticalAlignment="Bottom" MaxHeight="50">
+                <Image Source="{Binding DarkenBg}" Stretch="UniformToFill" />
+                <TextBlock Text="{Binding Title}" VerticalAlignment="Bottom" HorizontalAlignment="Center" FontSize="35" Opacity="1" />
+            </Panel>
+        </Panel>
+    </Button>
+
+</UserControl>

UnitystationLauncher/Views/BlogPostView.axaml.cs

@@ -0,0 +1,17 @@
+using Avalonia.Controls;
+using Avalonia.Markup.Xaml;
+
+namespace UnitystationLauncher.Views;
+
+public class BlogPostView : UserControl
+{
+    public BlogPostView()
+    {
+        InitializeComponent();
+    }
+
+    private void InitializeComponent()
+    {
+        AvaloniaXamlLoader.Load(this);
+    }
+}

UnitystationLauncher/Views/NewsPanelView.xaml

@@ -42,7 +42,7 @@
                             <ColumnDefinition Width="0.8*" />
                             <ColumnDefinition Width="0.1*" />
                         </Grid.ColumnDefinitions>
-                        <Button Margin="0.6 0.6 0 0" Grid.Column="0" Command="{Binding PastVideo}">
+                        <Button Margin="0.6 0.6 0 0" Grid.Column="0" Command="{Binding PreviousBlog}">
                             <Grid>
                                 <Grid.RowDefinitions>
                                     <RowDefinition Height="0.25*" />
@@ -58,9 +58,8 @@
                                        Source="/Assets/leftbutton.png" Stretch="Uniform" />
                             </Grid>
                         </Button>
-                        <Image Grid.Column="0" Grid.ColumnSpan="3" Margin="0.5" Source="{Binding BackGroundImage}"
-                               Stretch="UniformToFill" Opacity="0.459" />
-                        <Button Margin="0 0.6 0.6 0" Grid.Column="2" Command="{Binding NextVideo}">
+                        <ContentControl Grid.Column="1" Content="{Binding CurrentBlogPost}" />
+                        <Button Margin="0 0.6 0.6 0" Grid.Column="2" Command="{Binding NextBlog}">
                             <Grid>
                                 <Grid.RowDefinitions>
                                     <RowDefinition Height="0.25*" />