Template Based Code Generator

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections.Specialized;
using Arebis.CodeGenerator.Templated;
using System.CodeDom.Compiler;
using System.Reflection;
using System.IO;

namespace Arebis.CommandLineTools.CodeGenerator
{
	/// <summary>
	/// A Generator object creates a GenerationHost and executes the initial template on it.
	/// This implementation will host the GenerationHost in a separate AppDomain to allow unload of assemblies.
	/// </summary>
	[System.Diagnostics.DebuggerStepThrough]
	public class Generator
	{
		private NameValueCollection settings = new NameValueCollection();
		private object[] templateParameters = new object[0];

		public NameValueCollection Settings
		{
			get { return this.settings; }
			set { this.settings = value; }
		}

		public object[] TemplateParameters
		{
			get { return this.templateParameters; }
			set { this.templateParameters = value; }
		}

		public virtual void ExecuteTemplate()
		{
			// Execute the (initial) template by GenerationHost in separate AppDomain:
			AppDomain appDomain = null;
			GenerationHost genHost = null;
			try
			{
				AppDomainSetup info = new AppDomainSetup();
				info.ApplicationBase = new FileInfo(Assembly.GetEntryAssembly().Location).Directory.FullName;
				info.ShadowCopyFiles = "true";
				appDomain = AppDomain.CreateDomain("CodeGenSpace", AppDomain.CurrentDomain.Evidence, info);
				genHost = (GenerationHost)appDomain.CreateInstance(typeof(GenerationHost).Assembly.FullName, typeof(GenerationHost).FullName).Unwrap();
				genHost.Initialize(this.Settings);
				this.ExecuteTemplate(genHost);
			}
			finally
			{
				if (genHost != null) genHost.Dispose();
				if (appDomain != null) AppDomain.Unload(appDomain);
			}
		}

		public virtual void ExecuteTemplate(GenerationHost genHost)
		{
			this.ExecuteTemplate(genHost, this.Settings["template"], this.settings["output"], this.TemplateParameters);
		}

		public virtual void ExecuteTemplate(GenerationHost genHost, string templateFilename, string outputFilename, object[] templateParameters)
		{
			try
			{
				genHost.Initialize(this.Settings);
				genHost.CallTemplateToFile(templateFilename, outputFilename, templateParameters);
			}
			catch (CompilationFailedException ex)
			{
				Console.WriteLine(String.Format("Compilation failed for file: {0}", ex.Filename));
				foreach (CompilerError err in ex.Errors)
				{
					Console.WriteLine(String.Format("{0} {1}: {2}\r\n  \"{3}\", line #{4}",
						err.IsWarning ? "Warning" : "Error",
						err.ErrorNumber,
						err.ErrorText,
						err.FileName,
						err.Line));
				}
			}
			catch (RuntimeException ex)
			{
				Console.WriteLine("Runtime exception: ");
				Console.WriteLine(ex.InnerException);
			}
		}
	}
}