Created UmbracoAuthorizeAttribute, UmbracoAuthorizedController for all base MVC controllers that required a back office user to be logged in.

Converted over the SaveTemplate and SavePartialView methods of the codeEditorSave legacy web service to use MVC services and marked them obsolete.
Created a generic route to route all controllers found in the namespace Umbraco.Web.WebServices. Added a 'Url' property on the BasePage webforms class
to expose a UrlHelper for use in views. Created UrlHelper extensions to easily get the base url path of the REST MVC web services.
Converted the EditView page and JavaScript to use the new REST services with jQuery instead of crappy MS ajax.

src/Umbraco.Web/WebServices/SaveFileController.cs

@@ -0,0 +1,154 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Web.Mvc;
+using Umbraco.Core.IO;
+using Umbraco.Core.Logging;
+using Umbraco.Web.Mvc;
+using umbraco;
+using umbraco.BasePages;
+using umbraco.cms.businesslogic.template;
+using umbraco.presentation.cache;
+
+namespace Umbraco.Web.WebServices
+{
+
+	/// <summary>
+	/// A REST controller used to save files such as templates, partial views, macro files, etc...
+	/// </summary>
+	/// <remarks>
+	/// This isn't fully implemented yet but we should migrate all of the logic in the umbraco.presentation.webservices.codeEditorSave
+	/// over to this controller.
+	/// </remarks>
+	public class SaveFileController : UmbracoAuthorizedController
+	{
+
+		/// <summary>
+		/// Saves a partial view for a partial view macr
+		/// </summary>
+		/// <param name="filename"></param>
+		/// <param name="oldName"></param>
+		/// <param name="contents"></param>
+		/// <returns></returns>
+		[HttpPost]
+		public JsonResult SavePartialView(string filename, string oldName, string contents)
+		{
+			var folderPath = SystemDirectories.MvcViews + "/Partials/";
+
+			// validate file
+			IOHelper.ValidateEditPath(IOHelper.MapPath(folderPath + filename), folderPath);
+			// validate extension
+			IOHelper.ValidateFileExtension(IOHelper.MapPath(folderPath + filename), new[] { "cshtml" }.ToList());
+			
+			var val = contents;
+			var saveOldPath = oldName.StartsWith("~/") ? IOHelper.MapPath(oldName) : IOHelper.MapPath(folderPath + oldName);
+			var savePath = filename.StartsWith("~/") ? IOHelper.MapPath(filename) : IOHelper.MapPath(folderPath + filename);
+
+			//Directory check.. only allow files in script dir and below to be edited
+			if (!savePath.StartsWith(IOHelper.MapPath(folderPath)))
+			{
+				return Failed(
+					ui.Text("speechBubbles", "partialViewErrorText"), ui.Text("speechBubbles", "partialViewErrorHeader"),
+					//pass in a new exception ... this will also append the the message
+					new ArgumentException("Illegal path: " + savePath));
+			}
+
+			//deletes the old file
+			if (savePath != saveOldPath)
+			{
+				if (System.IO.File.Exists(saveOldPath))
+					System.IO.File.Delete(saveOldPath);
+			}
+			using (var sw = System.IO.File.CreateText(savePath))
+			{
+				sw.Write(val);
+			}
+			return Success(ui.Text("speechBubbles", "partialViewSavedText"), ui.Text("speechBubbles", "partialViewSavedHeader"));
+		}
+
+		/// <summary>
+		/// Saves a template
+		/// </summary>
+		/// <param name="templateName"></param>
+		/// <param name="templateAlias"></param>
+		/// <param name="templateContents"></param>
+		/// <param name="templateId"></param>
+		/// <param name="masterTemplateId"></param>
+		/// <returns></returns>
+		[HttpPost]
+		public JsonResult SaveTemplate(string templateName, string templateAlias, string templateContents, int templateId, int masterTemplateId)
+		{
+			Template t;
+			try
+			{
+				t = new Template(templateId)
+						{
+							Text = templateName,
+							Alias = templateAlias,
+							MasterTemplate = masterTemplateId,
+							Design = templateContents
+						};
+			}
+			catch (ArgumentException ex)
+			{
+				//the template does not exist
+				return Failed("Template does not exist", ui.Text("speechBubbles", "templateErrorHeader"), ex);
+			}
+
+			try
+			{
+				t.Save();
+
+				// Clear cache in rutime
+				if (UmbracoSettings.UseDistributedCalls)
+					dispatcher.Refresh(new Guid("dd12b6a0-14b9-46e8-8800-c154f74047c8"), t.Id);
+				else
+					template.ClearCachedTemplate(t.Id);
+
+				return Success(ui.Text("speechBubbles", "templateSavedText"), ui.Text("speechBubbles", "templateSavedHeader"));
+			}
+			catch (Exception ex)
+			{
+				return Failed(ui.Text("speechBubbles", "templateErrorText"), ui.Text("speechBubbles", "templateErrorHeader"), ex);
+			}
+		}
+
+		/// <summary>
+		/// Returns a successful message
+		/// </summary>
+		/// <param name="message">The message to display in the speach bubble</param>
+		/// <param name="header">The header to display in the speach bubble</param>
+		/// <returns></returns>
+		private JsonResult Success(string message, string header)
+		{
+			return Json(new
+			{
+				success = true,
+				message = message,
+				header = header
+			});
+		}
+
+		/// <summary>
+		/// Returns a failed message
+		/// </summary>
+		/// <param name="message">The message to display in the speach bubble</param>
+		/// <param name="header">The header to display in the speach bubble</param>
+		/// <param name="exception">The exception if there was one</param>
+		/// <returns></returns>
+		private JsonResult Failed(string message, string header, Exception exception = null)
+		{
+			if (exception != null)
+				LogHelper.Error<SaveFileController>("An error occurred saving a file. " + message, exception);
+			return Json(new
+				{
+					success = false,
+					header = header,
+					message = message + (exception == null ? "" : (exception.Message + ". Check log for details."))
+				});
+		}
+
+	}
+}