Initial commit

Katteker.Gui/ChangelogHelper.cs

@@ -0,0 +1,61 @@
+using System;
+using System.IO;
+using System.Net;
+using System.Threading.Tasks;
+
+namespace Katteker.Gui
+{
+    internal static class ChangelogHelper
+    {
+        private static string GenerateHtmlifyChangelog(string text, string extension)
+        {
+            string result;
+            switch (extension)
+            {
+                case ".txt":
+                    var plainText = WebUtility.HtmlEncode(text);
+                    result = plainText.Replace(Environment.NewLine, "<br />");
+                    break;
+                case ".md":
+                    result = CommonMark.CommonMarkConverter.Convert(text);
+                    break;
+                default:
+                    result = text;
+                    break;
+            }
+
+            return result;
+        }
+
+        internal static async Task<string> LoadChangelogAsync(string filename, string path)
+        {
+            if (!string.IsNullOrEmpty(filename) || !string.IsNullOrEmpty(path))
+            {
+                if (!path.EndsWith("/", StringComparison.Ordinal))
+                    path += "/";
+                var webReq = WebRequest.Create(path + filename);
+                try
+                {
+                    using (var response = await webReq.GetResponseAsync().ConfigureAwait(false))
+                    using (var sr = new StreamReader(response.GetResponseStream()))
+                    {
+                        return GenerateHtmlifyChangelog(await sr.ReadToEndAsync().ConfigureAwait(false),
+                            Path.GetExtension(filename));
+                    }
+                }
+                catch (WebException)
+                {
+                    var changelogFilename = Path.GetFileName(filename);
+                    if (changelogFilename == null) return GenerateHtmlifyChangelog("Changelog not found", ".txt");
+                    var currentChangelogPath = Path.Combine(Environment.CurrentDirectory, changelogFilename);
+                    if (File.Exists(currentChangelogPath))
+                    {
+                        return GenerateHtmlifyChangelog(File.ReadAllText(currentChangelogPath), Path.GetExtension(filename));
+                    }
+                }
+            }
+
+            return GenerateHtmlifyChangelog("Changelog not found", ".txt");
+        }
+    }
+}