Add update check

.gitignore

@@ -8,4 +8,5 @@ bin/
 .vs/
 obj/
 *.DotSettings
-*.user
+*.user
+packages/

ACSE.csproj

@@ -54,6 +54,9 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="Microsoft.CSharp" />
+    <Reference Include="Newtonsoft.Json, Version=11.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed, processorArchitecture=MSIL">
+      <HintPath>packages\Newtonsoft.Json.11.0.2\lib\net45\Newtonsoft.Json.dll</HintPath>
+    </Reference>
     <Reference Include="System" />
     <Reference Include="System.Core" />
     <Reference Include="System.Data" />
@@ -82,6 +85,7 @@
       <Generator>SettingsSingleFileGenerator</Generator>
       <LastGenOutput>ItemColorSettings.Designer.cs</LastGenOutput>
     </None>
+    <None Include="packages.config" />
     <None Include="Resources\Animal_Crossing_NL_Badges_28x28.png" />
     <None Include="Resources\Animal_Crossing_NL_NoBadge_28x28.png" />
     <None Include="Resources\BoxGlow.png" />
@@ -4894,6 +4898,7 @@
     <Compile Include="Classes\Saves\SaveBase.cs" />
     <Compile Include="Classes\Saves\WiiSave.cs" />
     <Compile Include="Classes\TrainStation.cs" />
+    <Compile Include="Classes\Updater.cs" />
     <Compile Include="Classes\Utilities\ImageUtility.cs" />
     <Compile Include="Classes\Villagers\SimpleVillager.cs" />
     <Compile Include="Classes\Villagers\Villager.cs" />

Classes/Updater.cs

@@ -0,0 +1,104 @@
+using System.Diagnostics;
+using System.IO;
+using System.Net;
+using System.Reflection;
+using Newtonsoft.Json.Linq;
+
+namespace ACSE
+{
+    internal sealed class Updater
+    {
+        private int _versionMajor;
+        private int _versionMinor;
+        private int _versionRevision;
+
+        public string UpdateUrl { get; private set; }
+
+        private void SetCurrentVersionInfo()
+        {
+            var versionInfo = FileVersionInfo.GetVersionInfo(Assembly.GetExecutingAssembly().Location);
+            _versionMajor = versionInfo.FileMajorPart;
+            _versionMinor = versionInfo.FileMinorPart;
+            _versionRevision = versionInfo.ProductBuildPart;
+        }
+
+        public Updater()
+        {
+            SetCurrentVersionInfo();
+        }
+
+        public string GetVersion() => $"{_versionMajor}.{_versionMinor}.{_versionRevision}";
+
+        private (bool, string) CheckForUpdate(string url)
+        {
+            // Check the "latest" release first.
+            var request = (HttpWebRequest) WebRequest.Create(url);
+            request.Credentials = CredentialCache.DefaultCredentials;
+            request.ContentType = "application/json";
+            request.Method = "GET";
+            request.Accept = "application/json";
+            request.UserAgent = "ACSE";
+
+            // Read response.
+            string content;
+            try
+            {
+                var response = (HttpWebResponse) request.GetResponse();
+                using (var contentStream = response.GetResponseStream())
+                {
+                    if (contentStream == null) return (false, null);
+                    using (var reader = new StreamReader(contentStream))
+                    {
+                        content = reader.ReadToEnd();
+                    }
+                }
+            }
+            catch
+            {
+                return (false, null);
+            }
+
+            // Parse JSON.
+            JObject jObj;
+            switch (JToken.Parse(content))
+            {
+                case JArray jArray:
+                    jObj = (JObject) jArray[0];
+                    break;
+                case JObject jObject:
+                    jObj = jObject;
+                    break;
+                default:
+                    return (false, null);
+            }
+
+            var version = (string) jObj["tag_name"];
+            var updateUrl = (string) jObj["html_url"];
+
+            try
+            {
+                var versionInfo = version.Split('.');
+                var updateMajor = int.Parse(versionInfo[0]);
+                var updateMinor = int.Parse(versionInfo[1]);
+                var updateRevision = int.Parse(versionInfo[2]);
+
+                return (updateMajor > _versionMajor || updateMinor > _versionMinor || updateRevision > _versionRevision, updateUrl);
+            }
+            catch
+            {
+                return (false, null);
+            }
+        }
+
+        public bool HasUpdate()
+        {
+            var (latestResult, latestUrl) = CheckForUpdate(@"https://api.github.com/repos/cuyler36/ACSE/releases/latest");
+            UpdateUrl = latestUrl;
+            if (latestResult) return true;
+
+            var (releasesResult, releaseUrl) = CheckForUpdate(@"https://api.github.com/repos/cuyler36/ACSE/releases");
+            UpdateUrl = releaseUrl;
+            return releasesResult;
+        }
+    }
+}

Forms/MainForm.cs

@@ -260,6 +260,16 @@ public MainForm()
             // Palette Change Buttons
             paletteNextButton.MouseClick += (sender, e) => ChangePatternPalette(1);
             palettePreviousButton.MouseClick += (sender, e) => ChangePatternPalette(-1);
+
+            // Check for updates
+            var updater = new Updater();
+            if (updater.HasUpdate() &&
+                MessageBox.Show(
+                    "An updated version of ACSE is available! Would you like to be taken to the download page?",
+                    "ACSE Update", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes)
+            {
+                System.Diagnostics.Process.Start(updater.UpdateUrl);
+            }
         }
 
         #region Settings Changing Functions

packages.config

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="Newtonsoft.Json" version="11.0.2" targetFramework="net47" />
+</packages>