// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
using System;
using ICSharpCode.SharpDevelop.Dom;
using ICSharpCode.SharpDevelop.Dom.CSharp;
using ICSharpCode.SharpDevelop.Dom.NRefactoryResolver;
using ILSpy.Debugger.AvalonEdit.Editor;

namespace ILSpy.Debugger.Services
{
	public class TParser : IParser
	{
		///<summary>IParser Interface</summary>
		string[] lexerTags;
		
		public string[] LexerTags {
			get {
				return lexerTags;
			}
			set {
				lexerTags = value;
			}
		}
		
		public LanguageProperties Language {
			get {
				return LanguageProperties.CSharp;
			}
		}
		
		public IExpressionFinder CreateExpressionFinder(string fileName)
		{
			return new CSharpExpressionFinder(null);
		}
		
		void RetrieveRegions(ICompilationUnit cu, ICSharpCode.NRefactory.Parser.SpecialTracker tracker)
		{
			for (int i = 0; i < tracker.CurrentSpecials.Count; ++i) {
				ICSharpCode.NRefactory.PreprocessingDirective directive = tracker.CurrentSpecials[i] as ICSharpCode.NRefactory.PreprocessingDirective;
				if (directive != null) {
					if (directive.Cmd == "#region") {
						int deep = 1;
						for (int j = i + 1; j < tracker.CurrentSpecials.Count; ++j) {
							ICSharpCode.NRefactory.PreprocessingDirective nextDirective = tracker.CurrentSpecials[j] as ICSharpCode.NRefactory.PreprocessingDirective;
							if (nextDirective != null) {
								switch (nextDirective.Cmd) {
									case "#region":
										++deep;
										break;
									case "#endregion":
										--deep;
										if (deep == 0) {
											cu.FoldingRegions.Add(new FoldingRegion(directive.Arg.Trim(), DomRegion.FromLocation(directive.StartPosition, nextDirective.EndPosition)));
											goto end;
										}
										break;
								}
							}
						}
						end: ;
					}
				}
			}
		}
		
		public ICompilationUnit Parse(IProjectContent projectContent, string fileName, ITextBuffer fileContent)
		{
			using (ICSharpCode.NRefactory.IParser p = ICSharpCode.NRefactory.ParserFactory.CreateParser(ICSharpCode.NRefactory.SupportedLanguage.CSharp, fileContent.CreateReader())) {
				return Parse(p, fileName, projectContent);
			}
		}
		
		ICompilationUnit Parse(ICSharpCode.NRefactory.IParser p, string fileName, IProjectContent projectContent)
		{
			p.Lexer.SpecialCommentTags = lexerTags;
			p.ParseMethodBodies = false;
			p.Parse();
			
			NRefactoryASTConvertVisitor visitor = new NRefactoryASTConvertVisitor(projectContent, ICSharpCode.NRefactory.SupportedLanguage.CSharp);
			visitor.Specials = p.Lexer.SpecialTracker.CurrentSpecials;
			visitor.VisitCompilationUnit(p.CompilationUnit, null);
			visitor.Cu.FileName = fileName;
			visitor.Cu.ErrorsDuringCompile = p.Errors.Count > 0;
			RetrieveRegions(visitor.Cu, p.Lexer.SpecialTracker);
			AddCommentTags(visitor.Cu, p.Lexer.TagComments);
			return visitor.Cu;
		}
		
		void AddCommentTags(ICompilationUnit cu, System.Collections.Generic.List<ICSharpCode.NRefactory.Parser.TagComment> tagComments)
		{
			foreach (ICSharpCode.NRefactory.Parser.TagComment tagComment in tagComments) {
				DomRegion tagRegion = new DomRegion(tagComment.StartPosition.Y, tagComment.StartPosition.X);
				var tag = new ICSharpCode.SharpDevelop.Dom.TagComment(tagComment.Tag, tagRegion, tagComment.CommentText);
				cu.TagComments.Add(tag);
			}
		}
		
		public IResolver CreateResolver()
		{
			return new NRefactoryResolver(LanguageProperties.CSharp);
		}
		///////// IParser Interface END
	}
}