// 
// IntroduceFormatItem.cs
//  
// Author:
//       Mike Krüger <mkrueger@novell.com>
// 
// Copyright (c) 2011 Novell, Inc (http://www.novell.com)
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

using System;
using ICSharpCode.NRefactory.PatternMatching;
using System.Collections.Generic;
using System.Linq;
using System.Threading;

namespace ICSharpCode.NRefactory.CSharp.Refactoring
{
	/// <summary>
	/// Introduce format item. Works on strings that contain selections.
	/// "this is <some> string" => string.Format ("this is {0} string", <some>)
	/// </summary>
	[ContextAction("Introduce format item", Description = "Creates a string.format call with the selection as parameter.")]
	public class IntroduceFormatItemAction : ICodeActionProvider
	{
		readonly static MemberReferenceExpression PrototypeFormatReference = new MemberReferenceExpression (new TypeReferenceExpression (new PrimitiveType ("string")), "Format");
		
		public IEnumerable<CodeAction> GetActions(RefactoringContext context)
		{
			if (!context.IsSomethingSelected) {
				yield break;
			}
			var pexpr = context.GetNode<PrimitiveExpression>();
			if (pexpr == null || !(pexpr.Value is string)) {
				yield break;
			}
			if (pexpr.LiteralValue.StartsWith("@", StringComparison.Ordinal)) {
				if (!(pexpr.StartLocation < new TextLocation(context.Location.Line, context.Location.Column - 1) && new TextLocation(context.Location.Line, context.Location.Column + 1) < pexpr.EndLocation)) {
					yield break;
				}
			} else {
				if (!(pexpr.StartLocation < context.Location && context.Location < pexpr.EndLocation)) {
					yield break;
				}
			}

			yield return new CodeAction (context.TranslateString("Introduce format item"), script => {
				var invocation = context.GetNode<InvocationExpression>();
				if (invocation != null && invocation.Target.IsMatch(PrototypeFormatReference)) {
					AddFormatCallToInvocation(context, script, pexpr, invocation);
					return;
				}
			
				var arg = CreateFormatArgument(context);
				var newInvocation = new InvocationExpression (PrototypeFormatReference.Clone()) {
					Arguments = { CreateFormatString(context, pexpr, 0), arg }
				};
			
				script.Replace(pexpr, newInvocation);
				script.Select(arg);
			}, pexpr);

		}
		
		void AddFormatCallToInvocation (RefactoringContext context, Script script, PrimitiveExpression pExpr, InvocationExpression invocation)
		{
			var newInvocation = (InvocationExpression)invocation.Clone ();
			
			newInvocation.Arguments.First ().ReplaceWith (CreateFormatString (context, pExpr, newInvocation.Arguments.Count () - 1));
			newInvocation.Arguments.Add (CreateFormatArgument (context));
			
			script.Replace (invocation, newInvocation);
		}
		
		static PrimitiveExpression CreateFormatArgument (RefactoringContext context)
		{
			return new PrimitiveExpression (context.SelectedText);
		}
		
		static PrimitiveExpression CreateFormatString(RefactoringContext context, PrimitiveExpression pExpr, int argumentNumber)
		{
			var start = context.GetOffset(pExpr.StartLocation);
			var end = context.GetOffset(pExpr.EndLocation);
			var sStart = context.GetOffset(context.SelectionStart);
			var sEnd = context.GetOffset(context.SelectionEnd);
			return new PrimitiveExpression("", context.GetText(start, sStart - start) + "{" + argumentNumber + "}" + context.GetText(sEnd, end - sEnd));
		}
	}
}
