// 
// JoinStringAction.cs
// 
// Author:
//      Mansheng Yang <lightyang0@gmail.com>
// 
// Copyright (c) 2012 Mansheng Yang <lightyang0@gmail.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.

namespace ICSharpCode.NRefactory.CSharp.Refactoring
{
	[ContextAction ("Join string literal", Description = "Join string literals.")]
	public class JoinStringAction : SpecializedCodeAction<BinaryOperatorExpression>
	{
		protected override CodeAction GetAction (RefactoringContext context, BinaryOperatorExpression node)
		{
			if (node.Operator != BinaryOperatorType.Add)
				return null;

			PrimitiveExpression left;
			var leftBinaryOperatorExpr = node.Left as BinaryOperatorExpression;
			if (leftBinaryOperatorExpr != null && leftBinaryOperatorExpr.Operator == BinaryOperatorType.Add) {
				left = leftBinaryOperatorExpr.Right as PrimitiveExpression;
			} else {
				left = node.Left as PrimitiveExpression;
			}
			var right = node.Right as PrimitiveExpression;

			if (left == null || right == null ||
				!(left.Value is string) || !(right.Value is string) || !node.OperatorToken.Contains(context.Location))
				return null;

			var isLeftVerbatim = left.LiteralValue.StartsWith("@", System.StringComparison.Ordinal);
			var isRightVerbatime = right.LiteralValue.StartsWith("@", System.StringComparison.Ordinal);
			if (isLeftVerbatim != isRightVerbatime)
				return null;

			return new CodeAction (context.TranslateString ("Join strings"), script => {
				var start = context.GetOffset (left.EndLocation) - 1;
				var end = context.GetOffset (right.StartLocation) + (isLeftVerbatim ? 2 : 1);
				script.RemoveText (start, end - start);
			}, node.OperatorToken);
		}
	}
}
