// 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 System.Threading.Tasks;
using CSharpBinding.Parser;
using ICSharpCode.NRefactory.CSharp;
using ICSharpCode.NRefactory.CSharp.Resolver;
using ICSharpCode.NRefactory.CSharp.TypeSystem;
using ICSharpCode.SharpDevelop.Refactoring;

namespace CSharpBinding
{
	/// <summary>
	/// C#-specific extension methods.
	/// </summary>
	public static class ExtensionMethods
	{
		public static async Task<CompilationUnit> GetCompilationUnitAsync(this EditorRefactoringContext editorContext)
		{
			var parseInfo = (await editorContext.GetParseInformationAsync().ConfigureAwait(false)) as CSharpFullParseInformation;
			if (parseInfo != null)
				return parseInfo.CompilationUnit;
			else
				return new CompilationUnit();
		}
		
		public static Task<CSharpAstResolver> GetAstResolverAsync(this EditorRefactoringContext editorContext)
		{
			return editorContext.GetCachedAsync(
				async ec => {
					var parseInfo = (await ec.GetParseInformationAsync().ConfigureAwait(false)) as CSharpFullParseInformation;
					var compilation = await ec.GetCompilationAsync().ConfigureAwait(false);
					if (parseInfo != null)
						return parseInfo.GetResolver(compilation);
					else
						return new CSharpAstResolver(compilation, new CompilationUnit(), new CSharpParsedFile(ec.FileName));
				});
		}
	}
}