// Copyright 2004-2007 Castle Project - http://www.castleproject.org/
// 
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// 
//     http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// MODIFICATIONS HAVE BEEN MADE TO THIS FILE

namespace MvcContrib.BrailViewEngine
{
	using System.Collections.Generic;
	using Boo.Lang;

	public class IgnoreNull : IQuackFu
	{
		private readonly object target;

		public IgnoreNull(object target)
		{
			this.target = target;
		}

		#region IQuackFu Members

		public object QuackGet(string name, object[] parameters)
		{
			if (name == "_IsIgnoreNullReferencingNotNullObject_")
				return target != null;

			if (target == null)
				return this;
			object value;
			if (IsNullOrEmpty(parameters))
				value = ExpandDuckTypedExpressions_WorkaroundForDuplicateVirtualMethods.GetProperty(target, name);
			else
				value = ExpandDuckTypedExpressions_WorkaroundForDuplicateVirtualMethods.GetSlice(target, name, parameters);
			return new IgnoreNull(value);
		}

		public object QuackSet(string name, object[] parameters, object obj)
		{
			if (target == null)
				return this;
			if (IsNullOrEmpty(parameters))
				ExpandDuckTypedExpressions_WorkaroundForDuplicateVirtualMethods.SetProperty(target, name, obj);
			else
				ExpandDuckTypedExpressions_WorkaroundForDuplicateVirtualMethods.SetSlice(target, name,
				                                                                         GetParameterArray(parameters, obj));
			return this;
		}

		public object QuackInvoke(string name, object[] args)
		{
			if (target == null)
				return this;
			object value = ExpandDuckTypedExpressions_WorkaroundForDuplicateVirtualMethods.Invoke(target, name, args);
			return new IgnoreNull(value);
		}

		#endregion

		private static bool IsNullOrEmpty(object[] parameters)
		{
			return parameters == null || parameters.Length == 0;
		}

		private static object[] GetParameterArray(object[] parameters, object obj)
		{
			return new List<object>(parameters) {obj}.ToArray();
		}

		public override string ToString()
		{
			if (target == null)
				return string.Empty;
			return target.ToString();
		}

		public static bool AreEqual(object left, object right)
		{
			var temp = left as IgnoreNull;
			if (temp != null)
				left = temp.target;
			temp = right as IgnoreNull;
			if (temp != null)
				right = temp.target;
			return Equals(left, right);
		}
	}
}