Improve dme modifications

src/Tgstation.Server.Host/Components/DreamMaker.cs

@@ -181,16 +181,21 @@ namespace Tgstation.Server.Host.Components
 
 			var dmeModifications = await dmeModificationsTask.ConfigureAwait(false);
 
-			if (!dmeModifications.Any())
+			if (dmeModifications == null || dmeModifications.TotalDmeOverwrite)
 				return;
 
 			var dmeLines = new List<string>(dme.Split(new[] { Environment.NewLine }, StringSplitOptions.None));
 			for (var I = 0; I < dmeLines.Count; ++I)
 			{
 				var line = dmeLines[I];
-				if (line.Contains("BEGIN_INCLUDE"))
+				if (line.Contains("BEGIN_INCLUDE") && dmeModifications.HeadIncludeLine != null)
 				{
-					dmeLines.InsertRange(I + 1, dmeModifications);
+					dmeLines.Insert(I + 1, dmeModifications.HeadIncludeLine);
+					++I;
+				}
+				else if (line.Contains("END_INCLUDE") && dmeModifications.TailIncludeLine != null)
+				{
+					dmeLines.Insert(I - 1, dmeModifications.TailIncludeLine);
 					break;
 				}
 			}

src/Tgstation.Server.Host/Components/IConfiguration.cs

@@ -16,8 +16,8 @@ namespace Tgstation.Server.Host.Components
 		/// </summary>
 		/// <param name="destination">Path to the destination folder</param>
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation</param>
-		/// <returns>A <see cref="Task{TResult}"/> resultin in a <see cref="IReadOnlyList{T}"/> of #include lines for the .dm files copied</returns>
-		Task<IReadOnlyList<string>> CopyDMFilesTo(string destination, CancellationToken cancellationToken);
+		/// <returns>A <see cref="Task{TResult}"/> resulting in the <see cref="ServerSideModifications"/> if any</returns>
+		Task<ServerSideModifications> CopyDMFilesTo(string destination, CancellationToken cancellationToken);
 
 		/// <summary>
 		/// Symlinks all directories in the GameData directory to <paramref name="destination"/>

src/Tgstation.Server.Host/Components/ServerSideModifications.cs

@@ -0,0 +1,38 @@
+using System;
+
+namespace Tgstation.Server.Host.Components
+{
+	/// <summary>
+	/// Represents code modifications via configuration
+	/// </summary>
+	sealed class ServerSideModifications
+	{
+		/// <summary>
+		/// If the target dme was completely overwitten
+		/// </summary>
+		public bool TotalDmeOverwrite { get; }
+
+		/// <summary>
+		/// The #include line which should be added to the beginning of the .dme if any
+		/// </summary>
+		public string HeadIncludeLine { get; }
+
+		/// <summary>
+		/// The #include line which should be added to the end of the .dme if any
+		/// </summary>
+		public string TailIncludeLine { get; }
+
+		/// <summary>
+		/// Construct <see cref="ServerSideModifications"/>
+		/// </summary>
+		/// <param name="headIncludeLine">The value of <see cref="HeadIncludeLine"/></param>
+		/// <param name="tailIncludeLine">The value of <see cref="TailIncludeLine"/></param>
+		/// <param name="totalDmeOverwrite">The value of <see cref="TotalDmeOverwrite"/></param>
+		public ServerSideModifications(string headIncludeLine, string tailIncludeLine, bool totalDmeOverwrite)
+		{
+			HeadIncludeLine = headIncludeLine;
+			TailIncludeLine = tailIncludeLine;
+			TotalDmeOverwrite = totalDmeOverwrite;
+		}
+	}
+}