using System;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.ComponentModel.Design.Serialization;
using System.Collections;
using System.Diagnostics;
using System.Globalization;
using System.IO;
using System.Reflection;
using System.Runtime.Serialization.Formatters.Soap;
using System.Runtime.Serialization.Formatters.Binary;
using System.Text;
using System.Windows.Forms;
using System.Xml;
using System.CodeDom.Compiler;
using System.CodeDom;
using System.Drawing;
using Microsoft.CSharp;
using Microsoft.VisualBasic;

namespace Loader
{
    /// <summary>
    /// Inherits from CodeDomDesignerLoader. It can generate C# or VB code
    /// for a HostSurface. This loader does not support parsing a 
    /// C# or VB file.
    /// </summary>
	public class CodeDomHostLoader : CodeDomDesignerLoader
	{
		CSharpCodeProvider _csCodeProvider = new CSharpCodeProvider();
		CodeCompileUnit codeCompileUnit = null;
        CodeGen cg = null;
		TypeResolutionService _trs = null;
		private string executable;
		private Process run;
		
		public CodeDomHostLoader()
		{
			_trs = new TypeResolutionService();
		}

        protected override ITypeResolutionService TypeResolutionService
		{
			get
			{
				return _trs;
			}
		}

		protected override CodeDomProvider CodeDomProvider
		{
			get
			{
				return _csCodeProvider;
			}
		}

        /// <summary>
        /// Bootstrap method - loads a blank Form
        /// </summary>
        /// <returns></returns>
		protected override CodeCompileUnit Parse()
		{
			CodeCompileUnit ccu = null;

			DesignSurface ds = new DesignSurface();
			ds.BeginLoad(typeof(Form));
            IDesignerHost idh = (IDesignerHost)ds.GetService(typeof(IDesignerHost));
			idh.RootComponent.Site.Name = "Form1";

            cg = new CodeGen();
            ccu = cg.GetCodeCompileUnit(idh);

			AssemblyName[] names = Assembly.GetExecutingAssembly().GetReferencedAssemblies();
			for (int i = 0; i < names.Length; i++)
			{
				Assembly assembly = Assembly.Load(names[i]);
				ccu.ReferencedAssemblies.Add(assembly.Location);
			}

			codeCompileUnit = ccu;
			return ccu;
		}

        /// <summary>
        /// When the Loader is Flushed this method is called. The base class
        /// (CodeDomDesignerLoader) creates the CodeCompileUnit. We
        /// simply cache it and use this when we need to generate code from it.
        /// To generate the code we use CodeProvider.
        /// </summary>
		protected override void Write(CodeCompileUnit unit)
		{
			codeCompileUnit = unit;
		}

		protected override void OnEndLoad(bool successful, ICollection errors)
		{
			base.OnEndLoad(successful, errors);
			if (errors != null)
			{
				IEnumerator ie = errors.GetEnumerator();
				while (ie.MoveNext())
					System.Diagnostics.Trace.WriteLine(ie.Current.ToString());
			}
		}

		#region Public methods

        /// <summary>
        /// Flushes the host and returns the updated CodeCompileUnit
        /// </summary>
        /// <returns></returns>
		public CodeCompileUnit GetCodeCompileUnit()
		{
            Flush();
            return codeCompileUnit;
		}

        /// <summary>
        /// This method writes out the contents of our designer in C# and VB.
		/// It generates code from our codeCompileUnit using CodeRpovider
        /// </summary>
        public string GetCode(string context)
		{
            Flush();

			CodeGeneratorOptions o = new CodeGeneratorOptions();

			o.BlankLinesBetweenMembers = true;
			o.BracingStyle = "C";
			o.ElseOnClosing = false;
			o.IndentString = "    ";
            if (context == "C#")
			{
				StringWriter swCS = new StringWriter();
				CSharpCodeProvider cs = new CSharpCodeProvider();

				cs.GenerateCodeFromCompileUnit(codeCompileUnit, swCS, o);
				string code = swCS.ToString();
				swCS.Close();
				return code;
			}
			else if (context == "VB")
			{
				StringWriter swVB = new StringWriter();
				VBCodeProvider vb = new VBCodeProvider();

				vb.GenerateCodeFromCompileUnit(codeCompileUnit, swVB, o);
				string code = swVB.ToString();
				swVB.Close();
				return code;
			}

			return String.Empty;
		}

 
		#endregion

		#region Build and Run

        /// <summary>
		/// Called when we want to build an executable. Returns true if we succeeded.
        /// </summary>
        public bool Build()
		{
			Flush();

			// If we haven't already chosen a spot to write the executable to,
			// do so now.
			if (executable == null)
			{
				SaveFileDialog dlg = new SaveFileDialog();

				dlg.DefaultExt = "exe";
				dlg.Filter = "Executables|*.exe";
				if (dlg.ShowDialog() == DialogResult.OK)
				{
					executable = dlg.FileName;
				}
			}

			if (executable != null)
			{
				// We need to collect the parameters that our compiler will use.
				CompilerParameters cp = new CompilerParameters();
				AssemblyName[] assemblyNames = Assembly.GetEntryAssembly().GetReferencedAssemblies();

				foreach (AssemblyName an in assemblyNames)
				{
					Assembly assembly = Assembly.Load(an);
					cp.ReferencedAssemblies.Add(assembly.Location);
				}

				cp.GenerateExecutable = true;
				cp.OutputAssembly = executable;

				// Remember our main class is not Form, but Form1 (or whatever the user calls it)!
				cp.MainClass = "DesignerHostSample." + this.LoaderHost.RootComponent.Site.Name;

                CSharpCodeProvider cc = new CSharpCodeProvider();
				CompilerResults cr = cc.CompileAssemblyFromDom(cp, codeCompileUnit);

				if (cr.Errors.HasErrors)
				{
					string errors = "";

					foreach (CompilerError error in cr.Errors)
					{
						errors += error.ErrorText + "\n";
					}

					MessageBox.Show(errors, "Errors during compile.");
				}

				return !cr.Errors.HasErrors;
			}

			return false;
		}

        /// <summary>
        /// Here we build the executable and then run it. We make sure to not start
		/// two of the same process.
        /// </summary>
        public void Run()
		{
			if ((run == null) || (run.HasExited))
			{
				if (Build())
				{
					run = new Process();
					run.StartInfo.FileName = executable;
					run.Start();
				}
			}
		}

        /// <summary>
        /// Just in case the red X in the upper right isn't good enough,
		/// we can kill our process here.
        /// </summary>
        public void Stop()
		{
			if ((run != null) && (!run.HasExited))
			{
				run.Kill();
			}
		}

		#endregion

	}// class
}// namespace