/***************************************************************************
 *                             ScriptCompiler.cs
 *                            -------------------
 *   begin                : May 1, 2002
 *   copyright            : (C) The RunUO Software Team
 *   email                : info@runuo.com
 *
 *   $Id$
 *
 ***************************************************************************/

/***************************************************************************
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 ***************************************************************************/

using System;
using System.CodeDom;
using System.CodeDom.Compiler;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Reflection;
using System.Security.Cryptography;
using Microsoft.CSharp;
using Microsoft.VisualBasic;
using System.Diagnostics;

namespace Server
{
	public static class ScriptCompiler
	{
		private static Assembly[] m_Assemblies;

		public static Assembly[] Assemblies
		{
			get
			{
				return m_Assemblies;
			}
			set
			{
				m_Assemblies = value;
			}
		}

		private static List<string> m_AdditionalReferences = new List<string>();

		public static string[] GetReferenceAssemblies()
		{
			List<string> list = new List<string>();

			string path = Path.Combine( Core.BaseDirectory, "Data/Config/Assemblies.cfg" );

			if( File.Exists( path ) )
			{
				using( StreamReader ip = new StreamReader( path ) )
				{
					string line;

					while( (line = ip.ReadLine()) != null )
					{
						if( line.Length > 0 && !line.StartsWith( "#" ) )
							list.Add( line );
					}
				}
			}

			list.Add( Core.ExePath );

			list.AddRange( m_AdditionalReferences );

			return list.ToArray();
		}

		public static string GetDefines()
		{
			StringBuilder sb = null;

#if MONO
			AppendDefine( ref sb, "/d:MONO" );
#endif

			//These two defines are legacy, ie, depreciated.
			if( Core.Is64Bit )
				AppendDefine( ref sb, "/d:x64" );

			AppendDefine( ref sb, "/d:Framework_2_0" );

#if Framework_4_0
			AppendDefine( ref sb, "/d:Framework_4_0" );
#endif

			return (sb == null ? null : sb.ToString());
		}

		public static void AppendDefine( ref StringBuilder sb, string define )
		{
			if( sb == null )
				sb = new StringBuilder();
			else
				sb.Append( ' ' );

			sb.Append( define );
		}

		private static byte[] GetHashCode( string compiledFile, string[] scriptFiles, bool debug )
		{
			using( MemoryStream ms = new MemoryStream() )
			{
				using( BinaryWriter bin = new BinaryWriter( ms ) )
				{
					FileInfo fileInfo = new FileInfo( compiledFile );

					bin.Write( fileInfo.LastWriteTimeUtc.Ticks );

					foreach( string scriptFile in scriptFiles )
					{
						fileInfo = new FileInfo( scriptFile );

						bin.Write( fileInfo.LastWriteTimeUtc.Ticks );
					}

					bin.Write( debug );
					bin.Write( Core.Version.ToString() );

					ms.Position = 0;

					using( SHA1 sha1 = SHA1.Create() )
					{
						return sha1.ComputeHash( ms );
					}
				}
			}
		}

		public static bool CompileCSScripts( out Assembly assembly )
		{
			return CompileCSScripts( false, true, out assembly );
		}

		public static bool CompileCSScripts( bool debug, out Assembly assembly )
		{
			return CompileCSScripts( debug, true, out assembly );
		}

		public static bool CompileCSScripts( bool debug, bool cache, out Assembly assembly )
		{
			Console.Write( "Scripts: Compiling C# scripts..." );
			string[] files = GetScripts( "*.cs" );

			if( files.Length == 0 )
			{
				Console.WriteLine( "no files found." );
				assembly = null;
				return true;
			}

			if( File.Exists( "Scripts/Output/Scripts.CS.dll" ) )
			{
				if( cache && File.Exists( "Scripts/Output/Scripts.CS.hash" ) )
				{
					try
					{
						byte[] hashCode = GetHashCode( "Scripts/Output/Scripts.CS.dll", files, debug );

						using( FileStream fs = new FileStream( "Scripts/Output/Scripts.CS.hash", FileMode.Open, FileAccess.Read, FileShare.Read ) )
						{
							using( BinaryReader bin = new BinaryReader( fs ) )
							{
								byte[] bytes = bin.ReadBytes( hashCode.Length );

								if( bytes.Length == hashCode.Length )
								{
									bool valid = true;

									for( int i = 0; i < bytes.Length; ++i )
									{
										if( bytes[i] != hashCode[i] )
										{
											valid = false;
											break;
										}
									}

									if( valid )
									{
										assembly = Assembly.LoadFrom( "Scripts/Output/Scripts.CS.dll" );

										if( !m_AdditionalReferences.Contains( assembly.Location ) )
										{
											m_AdditionalReferences.Add( assembly.Location );
										}

										Console.WriteLine( "done (cached)" );

										return true;
									}
								}
							}
						}
					}
					catch
					{
					}
				}
			}

			DeleteFiles( "Scripts.CS*.dll" );

			using ( CSharpCodeProvider provider = new CSharpCodeProvider() )
			{
				string path = GetUnusedPath( "Scripts.CS" );

				CompilerParameters parms = new CompilerParameters( GetReferenceAssemblies(), path, debug );

				string defines = GetDefines();

				if( defines != null )
					parms.CompilerOptions = defines;

				if( Core.HaltOnWarning )
					parms.WarningLevel = 4;

#if !MONO
				CompilerResults results = provider.CompileAssemblyFromFile( parms, files );
#else
				parms.CompilerOptions = String.Format( "{0} /nowarn:169,219,414 /recurse:Scripts/*.cs", parms.CompilerOptions );
				CompilerResults results = provider.CompileAssemblyFromFile( parms, files );
#endif
				m_AdditionalReferences.Add( path );

				Display( results );

#if !MONO
				if( results.Errors.Count > 0 )
				{
					assembly = null;
					return false;
				}
#else
				if( results.Errors.Count > 0 ) {
					foreach( CompilerError err in results.Errors ) {
						if ( !err.IsWarning ) {
							assembly = null;
							return false;
						}
					}
				}
#endif


				if( cache && Path.GetFileName( path ) == "Scripts.CS.dll" )
				{
					try
					{
						byte[] hashCode = GetHashCode( path, files, debug );

						using( FileStream fs = new FileStream( "Scripts/Output/Scripts.CS.hash", FileMode.Create, FileAccess.Write, FileShare.None ) )
						{
							using( BinaryWriter bin = new BinaryWriter( fs ) )
							{
								bin.Write( hashCode, 0, hashCode.Length );
							}
						}
					}
					catch
					{
					}
				}

				assembly = results.CompiledAssembly;
				return true;
			}
		}

		public static void Display( CompilerResults results )
		{
			if( results.Errors.Count > 0 )
			{
				Dictionary<string, List<CompilerError>> errors = new Dictionary<string, List<CompilerError>>( results.Errors.Count, StringComparer.OrdinalIgnoreCase );
				Dictionary<string, List<CompilerError>> warnings = new Dictionary<string, List<CompilerError>>( results.Errors.Count, StringComparer.OrdinalIgnoreCase );

				foreach( CompilerError e in results.Errors )
				{
					string file = e.FileName;

					// Ridiculous. FileName is null if the warning/error is internally generated in csc.
					if ( string.IsNullOrEmpty( file ) ) {
						Console.WriteLine( "ScriptCompiler: {0}: {1}", e.ErrorNumber, e.ErrorText );
						continue;
					}

					Dictionary<string, List<CompilerError>> table = (e.IsWarning ? warnings : errors);

					List<CompilerError> list = null;
					table.TryGetValue( file, out list );

					if( list == null )
						table[file] = list = new List<CompilerError>();

					list.Add( e );
				}

				if( errors.Count > 0 )
					Console.WriteLine( "failed ({0} errors, {1} warnings)", errors.Count, warnings.Count );
				else
					Console.WriteLine( "done ({0} errors, {1} warnings)", errors.Count, warnings.Count );

				string scriptRoot = Path.GetFullPath( Path.Combine( Core.BaseDirectory, "Scripts" + Path.DirectorySeparatorChar ) );
				Uri scriptRootUri = new Uri( scriptRoot );

				Utility.PushColor( ConsoleColor.Yellow );

				if( warnings.Count > 0 )
					Console.WriteLine( "Warnings:" );

				foreach( KeyValuePair<string, List<CompilerError>> kvp in warnings )
				{
					string fileName = kvp.Key;
					List<CompilerError> list = kvp.Value;

					string fullPath = Path.GetFullPath( fileName );
					string usedPath = Uri.UnescapeDataString( scriptRootUri.MakeRelativeUri( new Uri( fullPath ) ).OriginalString );

					Console.WriteLine( " + {0}:", usedPath );

					Utility.PushColor( ConsoleColor.DarkYellow );

					foreach( CompilerError e in list )
						Console.WriteLine( "    {0}: Line {1}: {3}", e.ErrorNumber, e.Line, e.Column, e.ErrorText );

					Utility.PopColor();
				}

				Utility.PopColor();

				Utility.PushColor( ConsoleColor.Red );

				if( errors.Count > 0 )
					Console.WriteLine( "Errors:" );

				foreach( KeyValuePair<string, List<CompilerError>> kvp in errors )
				{
					string fileName = kvp.Key;
					List<CompilerError> list = kvp.Value;

					string fullPath = Path.GetFullPath( fileName );
					string usedPath = Uri.UnescapeDataString( scriptRootUri.MakeRelativeUri( new Uri( fullPath ) ).OriginalString );

					Console.WriteLine( " + {0}:", usedPath );

					Utility.PushColor( ConsoleColor.DarkRed );

					foreach( CompilerError e in list )
						Console.WriteLine( "    {0}: Line {1}: {3}", e.ErrorNumber, e.Line, e.Column, e.ErrorText );

					Utility.PopColor();
				}

				Utility.PopColor();
			}
			else
			{
				Console.WriteLine( "done (0 errors, 0 warnings)" );
			}
		}

		public static string GetUnusedPath( string name )
		{
			string path = Path.Combine( Core.BaseDirectory, String.Format( "Scripts/Output/{0}.dll", name ) );

			for( int i = 2; File.Exists( path ) && i <= 1000; ++i )
				path = Path.Combine( Core.BaseDirectory, String.Format( "Scripts/Output/{0}.{1}.dll", name, i ) );

			return path;
		}

		public static void DeleteFiles( string mask )
		{
			try
			{
				string[] files = Directory.GetFiles( Path.Combine( Core.BaseDirectory, "Scripts/Output" ), mask );

				foreach( string file in files )
				{
					try { File.Delete( file ); }
					catch { }
				}
			}
			catch
			{
			}
		}

		private delegate CompilerResults Compiler( bool debug );

		public static bool Compile()
		{
			return Compile( false );
		}

		public static bool Compile( bool debug )
		{
			return Compile( debug, true );
		}

		public static bool Compile( bool debug, bool cache )
		{
			EnsureDirectory( "Scripts/" );
			EnsureDirectory( "Scripts/Output/" );

			if( m_AdditionalReferences.Count > 0 )
				m_AdditionalReferences.Clear();

			List<Assembly> assemblies = new List<Assembly>();

			Assembly assembly;

			if( CompileCSScripts( debug, cache, out assembly ) )
			{
				if( assembly != null )
				{
					assemblies.Add( assembly );
				}
			}
			else
			{
				return false;
			}

			if( assemblies.Count == 0 )
			{
				return false;
			}

			m_Assemblies = assemblies.ToArray();

			Console.Write( "Scripts: Verifying..." );

			Stopwatch watch = Stopwatch.StartNew();
			
			Core.VerifySerialization();
			
			watch.Stop();

			Console.WriteLine("done ({0} items, {1} mobiles) ({2:F2} seconds)", Core.ScriptItems, Core.ScriptMobiles, watch.Elapsed.TotalSeconds);

			return true;
		}

		public static void Invoke( string method )
		{
			List<MethodInfo> invoke = new List<MethodInfo>();

			for( int a = 0; a < m_Assemblies.Length; ++a )
			{
				Type[] types = m_Assemblies[a].GetTypes();

				for( int i = 0; i < types.Length; ++i )
				{
					MethodInfo m = types[i].GetMethod( method, BindingFlags.Static | BindingFlags.Public );

					if( m != null )
						invoke.Add( m );
				}
			}

			invoke.Sort( new CallPriorityComparer() );

			for( int i = 0; i < invoke.Count; ++i )
				invoke[i].Invoke( null, null );
		}

		private static Dictionary<Assembly, TypeCache> m_TypeCaches = new Dictionary<Assembly, TypeCache>();
		private static TypeCache m_NullCache;

		public static TypeCache GetTypeCache( Assembly asm )
		{
			if( asm == null )
			{
				if( m_NullCache == null )
					m_NullCache = new TypeCache( null );

				return m_NullCache;
			}

			TypeCache c = null;
			m_TypeCaches.TryGetValue( asm, out c );

			if( c == null )
				m_TypeCaches[asm] = c = new TypeCache( asm );

			return c;
		}

		public static Type FindTypeByFullName( string fullName )
		{
			return FindTypeByFullName( fullName, true );
		}

		public static Type FindTypeByFullName( string fullName, bool ignoreCase )
		{
			Type type = null;

			for( int i = 0; type == null && i < m_Assemblies.Length; ++i )
				type = GetTypeCache( m_Assemblies[i] ).GetTypeByFullName( fullName, ignoreCase );

			if( type == null )
				type = GetTypeCache( Core.Assembly ).GetTypeByFullName( fullName, ignoreCase );

			return type;
		}

		public static Type FindTypeByName( string name )
		{
			return FindTypeByName( name, true );
		}

		public static Type FindTypeByName( string name, bool ignoreCase )
		{
			Type type = null;

			for( int i = 0; type == null && i < m_Assemblies.Length; ++i )
				type = GetTypeCache( m_Assemblies[i] ).GetTypeByName( name, ignoreCase );

			if( type == null )
				type = GetTypeCache( Core.Assembly ).GetTypeByName( name, ignoreCase );

			return type;
		}

		public static void EnsureDirectory( string dir )
		{
			string path = Path.Combine( Core.BaseDirectory, dir );

			if( !Directory.Exists( path ) )
				Directory.CreateDirectory( path );
		}

		public static string[] GetScripts( string filter )
		{
			List<string> list = new List<string>();

			GetScripts( list, Path.Combine( Core.BaseDirectory, "Scripts" ), filter );

			return list.ToArray();
		}

		public static void GetScripts( List<string> list, string path, string filter )
		{
			foreach( string dir in Directory.GetDirectories( path ) )
				GetScripts( list, dir, filter );

			list.AddRange( Directory.GetFiles( path, filter ) );
		}
	}

	public class TypeCache
	{
		private Type[] m_Types;
		private TypeTable m_Names, m_FullNames;

		public Type[] Types { get { return m_Types; } }
		public TypeTable Names { get { return m_Names; } }
		public TypeTable FullNames { get { return m_FullNames; } }

		public Type GetTypeByName( string name, bool ignoreCase )
		{
			return m_Names.Get( name, ignoreCase );
		}

		public Type GetTypeByFullName( string fullName, bool ignoreCase )
		{
			return m_FullNames.Get( fullName, ignoreCase );
		}

		public TypeCache( Assembly asm )
		{
			if( asm == null )
				m_Types = Type.EmptyTypes;
			else
				m_Types = asm.GetTypes();

			m_Names = new TypeTable( m_Types.Length );
			m_FullNames = new TypeTable( m_Types.Length );

			Type typeofTypeAliasAttribute = typeof( TypeAliasAttribute );

			for( int i = 0; i < m_Types.Length; ++i )
			{
				Type type = m_Types[i];

				m_Names.Add( type.Name, type );
				m_FullNames.Add( type.FullName, type );

				if( type.IsDefined( typeofTypeAliasAttribute, false ) )
				{
					object[] attrs = type.GetCustomAttributes( typeofTypeAliasAttribute, false );

					if( attrs != null && attrs.Length > 0 )
					{
						TypeAliasAttribute attr = attrs[0] as TypeAliasAttribute;

						if( attr != null )
						{
							for( int j = 0; j < attr.Aliases.Length; ++j )
								m_FullNames.Add( attr.Aliases[j], type );
						}
					}
				}
			}
		}
	}

	public class TypeTable
	{
		private Dictionary<string, Type> m_Sensitive, m_Insensitive;

		public void Add( string key, Type type )
		{
			m_Sensitive[key] = type;
			m_Insensitive[key] = type;
		}

		public Type Get( string key, bool ignoreCase )
		{
			Type t = null;

			if( ignoreCase )
				m_Insensitive.TryGetValue( key, out t );
			else
				m_Sensitive.TryGetValue( key, out t );

			return t;
		}

		public TypeTable( int capacity )
		{
			m_Sensitive = new Dictionary<string, Type>( capacity );
			m_Insensitive = new Dictionary<string, Type>( capacity, StringComparer.OrdinalIgnoreCase );
		}
	}
}