#region ================== Copyright (c) 2007 Pascal vd Heiden

/*
 * Copyright (c) 2007 Pascal vd Heiden, www.codeimp.com
 * This program is released under GNU General Public License
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 */

#endregion

#region ================== Namespaces

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Diagnostics;
using System.Reflection;
using System.IO;
using CodeImp.DoomBuilder.Config;


#endregion

namespace CodeImp.DoomBuilder.Compilers
{
	public abstract class Compiler : IDisposable
	{
		#region ================== Variables
		
		// Parameters
		protected readonly CompilerInfo info;
		protected string parameters;
		protected string workingdir;
		protected string sourcefile;
		protected string outputfile;
		protected string inputfile;
		protected HashSet<string> includes; //mxd
		
		// Files
		protected readonly DirectoryInfo tempdir;

		// Errors
		private readonly List<CompilerError> errors;
		
		// Disposing
		protected bool isdisposed;
		
		#endregion
		
		#region ================== Properties
		
		public string Parameters { get { return parameters; } set { parameters = value; } }
		public string WorkingDirectory { get { return workingdir; } set { workingdir = value; } }
		public string SourceFile { get { return sourcefile; } set { sourcefile = value; } }
		public string InputFile { get { return inputfile; } set { inputfile = value; } }
		public string OutputFile { get { return outputfile; } set { outputfile = value; } }
		public string Location { get { return tempdir.FullName; } }
		public HashSet<string> Includes { get { return includes; } set { includes = value; } } //mxd
		public bool CopyIncludesToWorkingDirectory; //mxd
		public bool IsDisposed { get { return isdisposed; } }
		public CompilerError[] Errors { get { return errors.ToArray(); } }
		
		#endregion
		
		#region ================== Constructor / Disposer
		
		// Constructor
		protected Compiler(CompilerInfo info, bool copyrequiredfiles)
		{
			// Initialize
			this.info = info;
			this.errors = new List<CompilerError>();
			this.includes = new HashSet<string>(StringComparer.OrdinalIgnoreCase); //mxd

			General.WriteLogLine("Creating compiler \"" + info.Name + "\" on interface \"" + this.GetType().Name + "\"...");
			
			// Create temporary directory
			tempdir = Directory.CreateDirectory(General.MakeTempDirname());
			workingdir = tempdir.FullName;

			//mxd. ACC compiler itself is not copied to tempdir anymore, so we don't need to move it's include files
			//but we still need tempdir to compile SCRIPTS lump.
			if(copyrequiredfiles)
			{
				// Copy required files to the temp directory
				General.WriteLogLine("Copying required files for compiler...");
				CopyRequiredFiles();
			}
		}
		
		// Disposer
		public virtual void Dispose()
		{
			if(!isdisposed)
			{
				Exception deleteerror;
				long starttime = Clock.CurrentTime;
				
				do
				{
					try
					{
						// Remove temporary directory
						General.WriteLogLine("Removing temporary compiler files...");
						tempdir.Delete(true);
						deleteerror = null;
					}
					catch(Exception e)
					{
						deleteerror = e;
					}

					// Bail out when it takes too long
					if((Clock.CurrentTime - starttime) > 2000) break;
				}
				while(deleteerror != null);
				
				// Report error if we have one
				if(deleteerror != null)
				{
					General.ErrorLogger.Add(ErrorType.Error, "Unable to remove temporary compiler files. " + deleteerror.GetType().Name + ": " + deleteerror.Message);
					General.WriteLogLine(deleteerror.StackTrace);
				}
				
				// Disposed
				isdisposed = true;
			}
		}
		
		#endregion
		
		#region ================== Methods

		// This copies all compiler files to a given destination
		private void CopyRequiredFiles()
		{
			// Copy files
			foreach(string f in info.Files)
			{
				string srcfile = Path.Combine(info.Path, f);
				if(!File.Exists(srcfile)) 
				{
					General.ErrorLogger.Add(ErrorType.Error, "The file \"" + f + "\" required by the \"" + info.Name + "\" compiler is missing. According to the compiler configuration in \"" + info.FileName + "\", it was expected to be found here: \"" + info.Path + "\"");
				} 
				else 
				{
					string tgtfile = Path.Combine(tempdir.FullName, f);
					File.Copy(srcfile, tgtfile, true);
				}
			}
		}
		
		/// <summary>
		/// This runs the compiler.
		/// </summary>
		/// <returns>Returns false when failed to start.</returns>
		public virtual bool Run() { return false; }

		/// <summary>
		/// Use this to report an error.
		/// </summary>
		protected void ReportError(CompilerError err)
		{
			this.errors.Add(err);
		}
		
		// This creates a compiler by interface name
		internal static Compiler Create(CompilerInfo info)
		{
			// Make list of assemblies to search in
			List<Assembly> asms = General.Plugins.GetPluginAssemblies();
			asms.Add(General.ThisAssembly);
			
			// Constructor arguments
			object[] args = new object[1];
			args[0] = info;
			
			try
			{
				// Go for all assemblies
				foreach(Assembly a in asms) 
				{
					// Find the class
					Type[] types = (Equals(a, General.ThisAssembly) ? a.GetTypes() : a.GetExportedTypes());

					foreach(Type t in types)
					{
						if(t.IsSubclassOf(typeof(Compiler)) && (t.Name == info.ProgramInterface))
						{
							// Create instance
							Compiler result = (Compiler)a.CreateInstance(t.FullName, false, BindingFlags.Default,
							                                             null, args, CultureInfo.CurrentCulture, new object[0]);
							return result;
						}
					}
				}
			}
			// Catch errors
			catch(TargetInvocationException e)
			{
				// Throw the actual exception
				Debug.WriteLine(DateTime.Now.ToShortDateString() + " " + DateTime.Now.ToShortTimeString());
				Debug.WriteLine(e.InnerException.Source + " throws " + e.InnerException.GetType().Name + ":");
				Debug.WriteLine(e.InnerException.Message);
				Debug.WriteLine(e.InnerException.StackTrace);
				throw e.InnerException;
			}

			// No such compiler
			return null;
		}
		
		#endregion
	}
}