//
// System.CodeDom.Compiler CodeGenerator class
//
// Author:
//   Miguel de Icaza (miguel@ximian.com)
//
// (C) 2001 Ximian, Inc.
//

using System.CodeDom;
using System.Reflection;
using System.IO;
	
namespace System.CodeDom.Compiler {

	public abstract class CodeGenerator : ICodeGenerator {
		protected TextWriter output;
		
		protected virtual  void ContinueOnNewLine (string st)
		{
		}

		CodeGenerator ()
		{
			indent = 8;
		}
		
		//
		// Code Generation methods
		//
		protected abstract void GenerateArrayCreateExpression (CodeArrayCreateExpression e);
		protected abstract void GenerateAssignStatement (CodeAssignStatement s);
		protected abstract void GenerateAttachEventStatement (CodeAttachEventStatement s);
		protected abstract void GenerateBaseReferenceExpression (CodeBaseReferenceExpression e);
		protected abstract void GenerateBinaryOperatorExpression (CodeBinaryOperatorExpression x);
		protected abstract void GenerateCastExpression (CodeCastExpression x);
		protected abstract void GenerateClasses (CodeNamespace x);
		protected abstract void GenerateCommentStatement (CodeCommentStatement x);
		protected abstract void GenerateConstructor (CodeConstructor x, CodeTypeDeclaration c);
		protected abstract void GenerateDelegateCreateExpression (CodeDelegateCreateExpression x);
		protected abstract void GenerateDelegateInvokeExpression (CodeDelegateInvokeExpression x);
		protected abstract void GenerateEvent (CodeMemberEvent x, CodeTypeDeclaration c);
		protected abstract void GenerateExpression (CodeExpression x);
		protected abstract void GenerateField (CodeMemberField x);
		protected abstract void GenerateFieldReferenceExpression (CodeFieldReferenceExpression x);
		protected abstract void GenerateIndexerExpression (CodeIndexerExpression x);
		protected abstract void GenerateLinePragmaStart (CodeLinePragma x);
		protected abstract void GenerateLinePragmaEnd (CodeLinePragma x);
		protected abstract void GenerateMethod (CodeMemberMethod m, CodeTypeDeclaration c);
		protected abstract void GenerateMethodInvokeExpression (CodeMethodInvokeExpression x);
		protected abstract void GenerateMethodReturnStatement (CodeMethodReturnStatement x);
		protected abstract void GenerateNamespace (CodeNamespace x);
		protected abstract void GenerateNamespaceStart (CodeNamespace x);
		protected abstract void GenerateNamespaceEnd (CodeNamespace x);
		protected abstract void GenerateNamespaceImport (CodeNamespaceImport i);
		protected abstract void GenerateNamespaceImports (CodeNamespace i);
		protected abstract void GenerateObjectCreateExpression (CodeObjectCreateExpression x);
		protected abstract void GenerateParameterDeclarationExpression (CodeParameterDeclarationExpression x);
		protected abstract void GeneratePrimitiveExpression (CodePrimitiveExpression x);
		protected abstract void GenerateProperty (CodeMemberProperty e, CodeTypeDeclaration c);
		protected abstract void GeneratePropertyReferenceExpression (CodePropertyReferenceExpression x);
		protected abstract void GenerateStatement (CodeStatement x);
		protected abstract void GenerateStatementCollection (CodeStatementCollection x);
		protected abstract void GenerateThisReferenceExpression (CodeThisReferenceExpression x);
		protected abstract void GenerateThrowExceptionStatement (CodeThrowExceptionStatement x);
		protected abstract void GenerateTryCatchFinallyStatement (CodeTryCatchFinallyStatement x);
		protected abstract void GenerateTypeOfExpression (CodeTypeOfExpression x);
		protected abstract void GenerateTypeReferenceExpression (CodeTypeReferenceExpression x);
		protected abstract void GenerateVariableDeclarationStatement (CodeVariableDeclarationStatement x);

		//
		// Other members
		//
		protected abstract string GetNullToken ();

		public abstract bool IsValidIdentifier (string value);

		public static bool IsValidLanguateIndependentIdentifier (string value)
		{
			/* FIXME: implement */
			return true;
		}

		//
		// Output functions
		//
		protected virtual void OutputAttributeArgument (CodeAttributeArgument arg)
		{
		}

		protected virtual void OutputDirection (FieldDirection dir)
		{
		}

		protected virtual void OutputExpressionList (CodeExpressionCollection c)
		{
		}

		protected virtual void OutputExpressionLIst (CodeExpressionCollection c, bool useNewlines)
		{
		}

		protected virtual void OutputFieldScopeModifier (MemberAttributes attrs)
		{
		}

		protected virtual void OutputIdentifier (string ident)
		{
		}

		protected virtual void OutputMemberAccessModifier (MemberAttributes attrs)
		{
		}

		protected virtual void OutputMemberScopeModifier (MemberAttributes attrs)
		{
		}

		protected virtual void OutputOperator (CodeBinaryOperatorType op)
		{
		}

		protected virtual void OutputParameters (CodeParameterDeclarationExpressionCollection pars)
		{
		}

		protected virtual void OutputType (string typeRef)
		{
		}

		protected virtual void OutputTypeAttributes (TypeAttributes attrs)
		{
		}

		protected virtual void OutputTypeNamePair (string typeRef, string name)
		{
		}


		protected abstract string QuoteLiteralString (string value);

		public virtual void ValidateIdentifier (string value)
		{
		}

		//
		// Properties
		//
		protected string currentClassName;
		protected string CurrentClassName {
			get {
				return currentClassName;
			}
		}
		
		protected CodeTypeMember codeClassMember;
		protected CodeTypeMember CurrentMember {
			get {
				return codeClassMember;
			}
		}

		protected string CurrentMemberName {
			get {
				return codeClassMember.Name;
			}
		}

		int indent;
		protected int Indent {
			get {
				return indent;
			}

			set {
				indent = value;
			}
		}

		//
		// This concept seems broken, I should not really be using
		// a flag, I should be "probing" what is being generated.
		// at least the Start/End
		// functions should not be abstract, or abstract could
		// have an implementation piece?
		//
		public bool isCurrentClass;
		protected bool IsCurrentClass {
			get {
				return isCurrentClass;
			}
		}

		public bool isCurrentDelegate;
		protected bool IsCurrentDelegate {
			get {
				return isCurrentDelegate;
			}
		}
		public bool isCurrentEnum;
		protected bool IsCurrentEnum {
			get {
				return isCurrentEnum;
			}
		}
		public bool isCurrentInterface;
		protected bool IsCurrentInterface {
			get {
				return isCurrentInterface;
			}
		}

		public bool isCurrentStruct;
		protected bool IsCurrentStruct {
			get {
				return isCurrentStruct;
			}
		}

		protected TextWriter Output {
			get {
				return output;
			}

			set {
				output = value;
			}
		}

                public abstract void GenerateCodeFromExpression (TextWriter output, CodeExpression expression);

                public abstract void GenerateCodeFromNamespace (TextWriter output, CodeExpression expression);

                public abstract void GenerateCodeFromStatement (TextWriter output, CodeStatement expression);
		
	}
}