// ***********************************************************************
// Copyright (c) 2007 Charlie Poole
//
// 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 NUnit.Framework.Constraints
{
	// TODO Needs tests
	/// <summary>
	/// ContainsConstraint tests a whether a string contains a substring
	/// or a collection contains an object. It postpones the decision of
	/// which test to use until the type of the actual argument is known.
	/// This allows testing whether a string is contained in a collection
	/// or as a substring of another string using the same syntax.
	/// </summary>
	public class ContainsConstraint : Constraint
	{
		readonly object expected;
		Constraint realConstraint;
        bool ignoreCase;

		private Constraint RealConstraint
		{
			get 
			{
				if ( realConstraint == null )
				{
                    if (actual is string)
                    {
                        StringConstraint constraint = new SubstringConstraint((string)expected);
                        if (this.ignoreCase)
                            constraint = constraint.IgnoreCase;
                        this.realConstraint = constraint;
                    }
                    else
                        this.realConstraint = new CollectionContainsConstraint(expected);
				}

				return realConstraint;
			}
			set 
			{ 
				realConstraint = value; 
			}
		}

        /// <summary>
        /// Initializes a new instance of the <see cref="ContainsConstraint"/> class.
        /// </summary>
        /// <param name="expected">The expected.</param>
		public ContainsConstraint( object expected )
		{
			this.expected = expected;
		}

        /// <summary>
        /// Flag the constraint to ignore case and return self.
        /// </summary>
        public ContainsConstraint IgnoreCase
        {
            get { this.ignoreCase = true; return this; }
        }

        /// <summary>
        /// Test whether the constraint is satisfied by a given value
        /// </summary>
        /// <param name="actual">The value to be tested</param>
        /// <returns>True for success, false for failure</returns>
		public override bool Matches(object actual)
		{
            this.actual = actual;
			return this.RealConstraint.Matches( actual );
		}

        /// <summary>
        /// Write the constraint description to a MessageWriter
        /// </summary>
        /// <param name="writer">The writer on which the description is displayed</param>
		public override void WriteDescriptionTo(MessageWriter writer)
		{
			this.RealConstraint.WriteDescriptionTo(writer);
		}
	}
}
