Support copying dependencies when going for cold-updates

src/NAppUpdate.Framework/Common/NauConfigurations.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
 
 namespace NAppUpdate.Framework.Common
@@ -39,5 +40,14 @@ public string BackupFolder
 		/// an UAC prompt in all cases.
 		/// </summary>
 		public string UpdateExecutableName { get; set; }
+
+		/// <summary>
+		/// A list of files (relative paths only) to be copied along with the NAppUpdate DLL and updater host
+		/// when performing cold updates. You need to set this only when you have a custom IUpdateTask that
+		/// takes dependency of an external DLL, or require other files side by side with them.
+		/// Custom IUpdateTasks taking dependencies of external DLLs which may require cold update, MUST reside
+		/// in an external class-library, never in the application EXE, for that reason.
+		/// </summary>
+		public List<string> DependenciesForColdUpdate { get; set; }
 	}
 }

src/NAppUpdate.Framework/Utils/NauIpc.cs

@@ -159,7 +159,21 @@ internal static void ExtractUpdaterFromResource(string updaterPath, string hostE
 			File.Copy(assemblyLocation, Path.Combine(updaterPath, "NAppUpdate.Framework.dll"));
 
 			// And also all other referenced DLLs (opt-in only)
-			// TODO typeof(UpdateStarter).Assembly.GetReferencedAssemblies()
+			var assemblyPath = Path.GetDirectoryName(assemblyLocation) ?? string.Empty;
+			if (UpdateManager.Instance.Config.DependenciesForColdUpdate != null)
+			{
+				// TODO Maybe we can back this up with typeof(UpdateStarter).Assembly.GetReferencedAssemblies()
+
+				foreach (var dep in UpdateManager.Instance.Config.DependenciesForColdUpdate)
+				{
+					string fullPath = Path.Combine(assemblyPath, dep);
+					if (!File.Exists(fullPath)) continue;
+
+					var dest = Path.Combine(updaterPath, dep);
+					FileSystem.CreateDirectoryStructure(dest);
+					File.Copy(fullPath, Path.Combine(updaterPath, dep));
+				}
+			}
 		}
 	}
 }